Changing Bike Frame - Legal Procedure..?

[Thanh-BKK]

Hello.

If i wanted to change the frame of my motorbike, what would be the procedure to get it legalized, and how much would it cost? I.e. entering the "new" frame number in the green book.

The reason is that the frame was broken and very poorly welded together by the previous owner, and now the bike's rear has a shape like a banana.

I could maybe find an undamaged frame in a junk yard, or a whole junk bike with ok frame, or even import a brand new frame from Malaysia where this bike (Yamaha RXZ) is still being sold.

In case if i import it, would it be classified as "spare part" or as "vehicle" as the frame is the one bit that carries the main identification number?

Or, would it be easier to get a whole junk bike (with green book!) and just rebuild it using mine complete bike, minus the broken frame, and have the change of engine legalized? It's the same engine obviously, just a different number.

Best regards.....

Thanh

[LivinLOS]

The frame number is (I am reliably informed) the one item that it is impossible to have changed in any way on the paperwork.

Hence why when people recycle books they change engine number / color / etc etc but the frame number has to be cut back and restamped.

I think your going to have problems with this unless you go the route of using a previously booked frame..

[HDRIDER]

HI

You can cut the old number out and weld it on the new frame, but they know that trick as well.

[goldfish]

I don't know how it works here but I was able to buy a new frame for a fireblade in the uk a few years ago which came unstamped. I bought some stamps, superglued a piece of plastic in place to act as a straight line, and stamped the frame myself. No authorities were any the wiser. Sold the bike a couple of years ago to a friend who promptly killed himself on it. He had no licence or legalities, the police were all over the bike (and kept it, although there wasn't much left) but were apparently unaware of its history.

Incidently, I was being quoted twice as much for a second hand frame and book from breakers

[Thanh-BKK]

Hi

Thank you all.... i had already thought something like that. Because i once talked to my mechanic, he said maybe they can send the frame (mine) to Yamaha who would then straighten it, but the problem is when the prev. owner welded the thing they somehow got it all messed up, the thing seems to be 1 cm shorter on the right than on the left...... it's only the upper rear, as the swing arm is perfectly in line, i.e. the rear wheel follows the front wheel exactly, still it looks like the "ass" of the bike is a good 5-6 cm's off to the right, even the shock absorbers tilt totally to the right. It looks horrible when you stand behind the bike, but strangely it's virtually unfeelable when driving (bike runs straight with no problems). And because of the messed-up welding it is not possible to ever straighten THAT frame again.

My mechanic said the cheapest would be to get either a junk bike or a frame without book, then cut the head tube from mine and weld it there, problem - i have a poorly welded frame NOW and don't trust in that "solution".

Yamaha (Malaysia) does not sell frames without frame number, i already asked there a while ago, every frame leaves the factory with a number and a certificate (if used for repair purpose) so in Malaysia this can be legalized.

So i guess my only chance would be to get a bike/frame WITH book and just put all the rest of my bike onto THAT frame, then register that one. Ok, not too big a problem..... now just have to find one Now, IS it possible to have the engine number changed, if so, how much will that cost? It's the same engine obviously, a standard RXZ engine.

Many thanks in advance for replies......

Best regards.....

Thanh

[davidgtr]

Not worth messing around with surely. Sell it & buy another bike.

[Thanh-BKK]

No!

That option does not exist. No new bike would give me what my Bulldozer gives me - this bike is as reliable as a Zuendapp, never lets me down, runs better than most new ones even tough it has 71,000 kilometers on the clock (plus an unknown number more as the speedo didn't work when i got it) and is, for a two-stroke, very economic at just under 3 liters/100 kilometers, half of which with passenger.

You could give me a Harley, BMW, Hayabusa or Ducati for free, i still wouldn't let my RXZ go.

And if it requires a new frame, it'll get a new frame, somehow.

Best regards......

Thanh

[stroker]

Yamaha (Malaysia) does not sell frames without frame number, i already asked there a while ago, every frame leaves the factory with a number and a certificate (if used for repair purpose) so in Malaysia this can be legalized.

Thanh

I'm not quite sure about this point. I've bought brand new frames from both BKK and Msia (Yamaha) that are un-stamped. Without frame numbers.

Edited May 24, 2008 by stroker

[Thanh-BKK]

Hi

I had a different problem with my bike a while back and that was when i got in touch with them as the RXZ is still made (and sold) in Malaysia. When i spoke to one of their technicians i brought up the subject of my broken and poorly welded frame, and he said i could buy one there but i would have to pay duty when importing it to Thailand, so i asked for the possibility to get one without a frame number, basically just as a spare part, and his reply was what i stated before - that every frame that leaves the factory comes with frame number and documentation, i.e. it is basically "a motorcycle" minus all the other parts.

If you previously bought Yamaha frames there, would you mind letting me know who you dealt with? Or, in case you still have an active business connection to them, would you mind just asking the price for an RXZ frame? There's only one RXZ model, the frames are unchanged from the early 90's until now.

Also did you have to pay import duties in any way? How did you get the frames here?

Do you do this as a business? If so, please let me know. I'm definitely interested if the frame is cheaper than an entire bike here (i paid 5,000 for mine, and good condition is about 12.000 still, if i get a junker with a straight frame for 5k it's fine for me).

Best regards......

Thanh

[Richard-BKK]

Than the problem with bikes like the RXZ is that they not cost that much. If I have a serious problem with a bigger bike, like the frame is beyond repair, we just buy a new frame and send the bike for re-registering. The cost for this is, regardless how much displacement the engine has, about 30,000 Baht (it is some time ago we did it the last time, but I’m sure that somebody at the Department of Land Transport can help you).

And surely motorcycle frames without a frame number? I not think so.......

[Thanh-BKK]

Hello

30k.... umph, i get 3 RXZ's for that, including green books and engines Meanwhile i was thinking to have my frame fixed again - actually if i would cut open the two upper tubes on the right side, bend the whole "ass" a little to the left so that there is a gap of maybe 1 cm in the tubes, then weld some rebar in there and some more around for strengthening.... could work. I need to get the rear end of the bike about 3-4 cm's to the left. It's probably the easiest solution - no hassle with frame numbers and don't even have to take the whole bike apart, just the rear, even the wheel can stay in...... Its sure wouldn't be perfect but certainly better road handling than now.

But i've got no welding machine. Time to get one

Best regards.....

Thanh

[Richard-BKK]

Thanh, my g/f told me that the 30k doesn't apply to motorcycles under the 250cc range, this to her idea this will not be more then the maximum of 600 Baht for motorcycle registration.

Sorry, we never try to change a frame of a smaller displacement motorcycle......... Still she says it can be a endless story for a end user, so probably better you contact a Yamaha dealer to inform them of your change and pay them to do the paperwork.

[MaiChai]

I think it would be best to get the frame repaired? RXZ is quite a small bike and doesn't require a super strengthen frame? A friend was telling me about an area down Sukhumwit out towards Bang Na where they do all sorts of car and bike 'surgery', so you should be able to find someone out there to do it for you?

Alternately buy a worn out RXZ (but with good frame) and move all your bike parts over to this frame (after a frame cleanup and respray). Make sure the donor bike is legit and has a green book. You could probably pick one up for 4000 baht; everyone is dumping their 2 strokers anyway.

I understand your feelings about your bike, but at the end of the day its quite a cheap second hand bike, and you need to be pragmatic about it. I have a Yamaha TZR150 that I bought for 7700 baht, and I have spent about another 4000 baht on fixing it up (over a year and a half now). Now its a great bike, and I love riding it in Bangkok, sliding between the traffic. But it has its warts too. Just had problems with the rear brake caliper; over the years Thai engineers have over tightened the bleed valve to the point where its pushed through to the cylinder and doesn't seal anymore. No one wants a bike that shakes to bits but it does irritate me that Thai engineers have no idea a torque settings and over tighten everything I managed to work around this issue by sealing the bleed outlet with copper wire and then soldering over it, but the piston is now leaking (I replaced the outer seal, but recent experiences with Thai spares have put me off replacing working bits with bits that may be out of spec; a good example was an original Honda carb service kit with bits seriously out of spec that cause problems with the choke). I was advised a new caliper would be a couple of thousand baht, and the guy in the parts shop recommended taking it to a machine shop to have it machined to take a Honda valve, which is much wider, and to have the seal recut so it seals again. Wife has a Belle R, which has the same caliper; maybe I should swap it... She is always falling off it anyway (brakes or no brakes); she blamed cobras out in the country (what an excuse!).

PS: If you buy another one maybe you can let me have the caliper (assuming they are the same)

[MaiChai]

Here is one for 2500 baht:

http://www.mocyc.com/store/detail.php?id=276650

[Thanh-BKK]

Here is one for 2500 baht:

http://www.mocyc.com/store/detail.php?id=276650

Good morning

Yup.... how they say "what looks to goods to be true probably is"..... an RXZ for 2,500 Baht, including an 150cc cylinder kit??

Of course, the provided phone number does not exist.

I'd buy that bike for the cylinder alone. I know i can fit a TZR kit on mine (the engines are nearly identical, except for the TZR's water cooling) so getting the pistons is no issue......

Regarding the brake caliper, you are aware that the RXZ does NOT have a rear disc brake? Mine DOES but i put it there myself, using parts from TZR (rear hub), Kawasaki (brake cylinder), after market (fake Brembo caliper, oversized shaped disc) and lots of home made stuff I got that stuff from Singapore where the RXZ, and hence also accessories for it, are still available.

As to "asking a Yamaha dealr", that's a no-go from the start. You walk in to a Yamaha dealer, mention "RXZ" and IMMEDIATELY get your "no have", regardless what you actually want t ask for. I had THAT experience the second day of owning my RXZ, asking for little "regular" things like a tank cap or speedmeter cable! And not only one Yamaha dealer, but several. The RXZ has last been sold in Thailand in 1995, and you probably know how it is here, in general - the moment a model is no longer sold, all spare parts are no longer available, either.

Small shops like the one i frequent in Phra Khanong can often get after market parts and even originals (like my exhaust, but it took over a year of searching for that one before i got it!) however a frame? No chance. Repairing it, yes, it IS an option, but as of yet i did not have the time, plain and simple - i need the bike every day, and having a frame fixed demands it being taken apart completely (deliver naked frame) and several days wait, then put back together. My only chance to have it done was during Songkhran - but no, that shop had to close in that time, too.

Which is why i now had that idea of doing a "sloppy" repair - my way. Just dismantle the rear (i have already ordered a new cover set from Singapore) and ride it there, then, with a simple saw, cut open the two tubes on the right side, bent the whole rear a few centimeters to the left, and weld it back together, using rebar or flat steel as reinforcement. When the frame first broke, they fixed it like that, BUT they used rebar pieces way too short so there is no stability, as a result the frame rear kept coming lower and lower and further and further to the right.

Yeah, it doesn't need superbike stability, but as i carry a passenger 50% of the time and heavy loads sometimes, too (several computers etc) it must be stable.

With kind regards......

Thanh

[MaiChai]

I figured it had a drum brake; front brake on the Belle R is the same as the rear brake on a TZR/VRR, so though this might be the case with the RXZ?

Sometimes getting things done in Thailand is frustrating; language is generally the barrier. I have been here 13 years and can speak some Thai but not fluent enough for sorting out technical stuff on bikes. Maybe Bangkokians don't have the patience to talk to a farang with clunky Thai? I get frustrated and I am sure you do?. I have worked in IT a long time, and we generally have two of everything in case something breaks. Why don't you buy another cheap bike to run around on while getting yours sorted out? I use my girlfriends Smash when mine is off the road (Smash's are cheap 2nd hand; this one was 9500 baht but her brother almost destroyed it and it needs something replacing in the clutch/drive train; will get round to sorting that out). Its a Wave clone and the basket is hand for short trips to 7/11, etc for ice, etc I also have a NSR150, but this is in the process of being rebuilt (and I am leaving this to next year when I come back; I prefer the TZR to the NSR; I dont think I like the NSR much so not much motivation to fix it up).

Have you come across any bike junk yards in Bangkok when you can rip bits off scrapped bikes? Would be interested to know. That rear caliper either needs taking to a workshop to drill it out for a larger Honda bleed valve (looks like someone already did this to the front brake), or I need to get hold of a replacement caliper. As you said, going to a Yamaha dealer will be pointless; either very expensive or they won't be interested in getting the part for me (interesting enough, Honda is always very helpful with parts for old bikes and quite often the prices are very reasonable).

Edited May 26, 2008 by MaiChai

[Thanh-BKK]

Hello

Regarding the shop, i am lucky here - i always go to a small "Somchai" type shop in soi Pridi Banomyong (Phra Khanong) where the owner is Chinese and quite fluent in English. Also once he know that i have the required knowledge he doesn't at all mind when i do most of the work myself, using basically his tools and space and buying my parts there. Even when i bring my own parts (like when i did my brake with all the bits coming from my friend in Singapore) i did most of it myself right there, his mechanic only taking care for getting the air out of the system (which is pretty tricky as the caliper is upside-down).

I have never been to a bike junkyard but would love to - if only i knew where to find one! I know this huge place to get car bits but nothing there for bikes.

As to your caliper, i haven't looked at a Belle R and i rarely see a TZR, however the rear caliper of a VRR looks to me like it could not be used anywhere on a front..... but then i might be wrong. I could have gone for a VRR caliper on mine (it fits on the RXZ if i modify my swing arm a little - i.e. drill one hole into it) however i didn't because the caliper is so freakin' expensive! I was quoted 6.900 Baht for a brand new one (genuine) and that's way too much, considered that i paid 5.000 for the whole bike So i went for the fake Brembo one, second hand from Singapore, with an adaptor plate so it accomodates the oversized disc (same size as front disc in fact) and i got the whole set for less than 3.000 Baht, all second hand of course. But i used a TZR hub and also bought a TZR disc first, then not knowing that the one from Singapore is larger If you need a brand new, unused, TZR rear disc let me know, it's wasting space in my room only

Fitting a larger bleed valve should only be a matter of drilling the hole bigger, cutting a new thread and thoroughly cleaning the thing after. Try one of the "Somchai" shops, they usually do that sort of repairs for small money. Go to one that actually does REPAIRS, not those that only bolt on "racing" parts to Finos and Sonics.

Good luck

your Thanh

[MaiChai]

I found a VRR on mocyc.com for 3000 baht; called the guy and he advised it was a VRR without power valve (sometimes people get confused; only the TZR/TZM150s have the power valve but sometimes a TZR is made to look like a VRR as the VRR looks more modern and then folks are unsure about what bike they have). Was interested in buying it for spares. Anyway the guy speaks some English and he seems to know his Thai bikes and seems to do alot of bike trading (mentioned that he gets alot of 'accicent' bikes). Maybe he can help you out with a tired old RXZ that you can steal the frame from; his number is 089 179 7099. He may even has a friend or contact in the business that can get you an old tired bike?

Managed to get a new O ring for the piston in the rear caliper; since that is leaking break fluid. Local bike shop had about four different VR types, and I went with a Belle R one since that was the one nearest the size. Bike spares in Thailand are not always exactly to spec; best to take the old one along and compare against the spares they have to make sure their spare is the same. Wasted half a day on the actuator for the rear brake; managed to get a new piston, which looked exactly the same as the original one, but was just a smidge too big to fit; I tried to file it down, but it would get stuck, so in the end stole the rubber seals off the new one and put on the old piston. Ho hum. Its all sorted now. Bleed valve seems not to leak now, so will monitor the new O ring and let it bed in for a few days. Anyway thanks for the offer on the rear disk; think mine is fine for now. Rear brake actuator piston on ebay I got this for 80 baht

We went out to celebrate the gf's birthday last night. Anyway we popped round to her cousins apartment, and in the car park is a TZR150 minus tank looking very abandoned and dusty. Have asked the gf to enquire if someone wants to sell it for spares. If they do then will take a good look at it to see if its worth buying; the power valve servo is expensive and dread that failing.

Edited May 27, 2008 by MaiChai

[Thanh-BKK]

Hello

Thank you for that, i appreciate it. I tried twice to call the number you gave me, it works but there is nobody answering.... seems i'm haunted. However on the weekend i will try to find that mysterious area "around National Stadium" that appears to have a number of second-hand motorbike parts shops or junk yards or something like that - i have been told by a number of people that this place does exist but, asking for location, i always get "around National Stadium" and nobody knows it exactly.

The other guy on mocyc.com (that cheap RXZ) never replied my e-mail either so i guess it's just a joke post.

About the VR, there seem to exist at least 4 different models, of which some don't have a rear disc brake but a drum, and others have aluminium cast wheels instead of spokes. Those would fit on an RXZ (and i would be interested!) but again - knowing they exist and finding them for sale is two entirely different things

Power valve? I am glad my engine doesn't have that thing....... Kawasaki has a similar system and i just can't stand them. Just another thing that promises more power but, when broken, makes for LESS power than without it. And any movable device hanging in the exhaust stream (and hence getting hot and collecting carbon) WILL break, sooner rather than later. My RXZ has the YEIS system ("boost bottle"), a passive device that creates a slight "turbo effect" beyond 5.000 rpm (including a "turbo hole" at 4.800 - 5.000 rpm!) and this is enough - it's not electronic, nothing movable, and hence it can't break.

The RXZ also (mine at least, some don't) has a "YCLS" electronic thingy that controls how much 2T oil goes to the engine - i have it disabled too, because anything "electronic" between my engine and the oil that keeps it alive is a disturbance only. I rather have a smokey exhaust than a new piston every few thousand kilometers (i drive a lot, currently more than 400 kilometers every week).

Update: The guy who's number you gave me called me back just now. He doesn't have anything "RXZ" and also doesn't know anyone who does, however he will send me a link from the same website where someone sells a RXZ for close to 5.000 Baht, including registration. That guy told me that frames can't be legally sold in Thailand due to the registration issue so a whole bike is the only possibility. Let's see

With kind regards.....

your Thanh

[MaiChai]

We should setup a bike business Truthfully this would be fun, but difficult to make a living out of.

The power valve design on Yamaha's is much better than on Honda (NSR) because you can service the Yamaha one without removing the cylinder head; I did this last week and cleaned out all the carbon buildup, and the valve is now much more responsive. I have had two Yamaha's and I prefer them to Hondas.

My NSR power valve system isn't working because the valve stuck and the servo then burned out; so when I got it, bike was running but no power valve operation; I have inquired about replacing this, but it would cost too much. I fixed up the carb; over flow pipe snapped (too many Somchais fixing it over the years!) so I put the overflow pipe back in upside down, and it was working fine, and when I took it for a test ride, piston seized. On investigation, it turns out someone had put the power valve in upside down and the piston had smashed into it! So I got a new piston and liner (1500 baht), and then got carb problems again (had it running up to 8000 rpm at one point with new cylinder/liner). So my plan is to just get it working again and then use it as a run around bike. Since I am heading back to the UK in July for 6 months, no point in fixing it up now since it will sit idle and then need resurrecting again when I return. So a project for next year

Just Googled YCLS; seems like it reduces smoke and saves 2T oil. This system has been around for a long time so it should be reliable?

I did see a TZR with a bottle on it; strapped on to the radiator; was wondering what that was for. My NSR has a smallish one, but I notice later NSRs have a much larger one; looks like I could take off the existing one and put a larger one on? My TZR does not have one so I will look out for modified bikes and then modify mine later; thanks for the tip, there is a hole in the performance in this rpm range and I think a bottle would sort it.

[MaiChai]

If you are prepared to wait, something will come up on mocyc.com. Just need to be patient, otherwise you will spend too much!

[Thanh-BKK]

Hi

Yeah, i checked out the link that guy sent me (from thaisecondhand.com), a beautiful red RXZ..... but when i called the owner (who spoke English) the bike was already sold since last week. Bummer.

But "your" guy also contacted the one from mocyc.com (that grey RXZ that is so cheap, turned out the number works after all but he doesn't speak a word English and hung up on me) and told me that the bike can be had for 2,000 Baht but is not driveable and has NO green book.

Plus it stands around Don Mueang airport - a good 50 kilometers from where i am! Hmm, not driveable, no book/plate, 50 kilometers - no go. Altough for that money i'd buy the cylinder alone, which is supposedly a 150cc one. I SO wish i had a pickup truck!! But then - cutting off my bent rear frame and welding the part from that book-less one onto it or just cutting, bending and re-welding mine doesn't make any difference.........

So yeah, i will try to find that mystic area around National Stadium on Saturday and see if i have any luck there - if not, "cutting and welding" it will be. I really don't fancy having two bikes for i'd need to pay for another parking spot and i can only drive one anyway - my boyfriend is scared to drive "such a big bike" (and afraid of the clutch!) even tough he has a license...... and no spare room to store a dismantled RXZ A spare engine, yes, but no more

About your NSR's problem, you said it idled at 8.000 rpm - doesn't look like a carb problem to me, more one of "false air" (don't know the correct English words), that is when the engine sucks in air beside the carb, such as thru a damaged cylinder foot gasket, damaged/porous intake seal or similar. If yopu can get hold of a can of "Start Pilot" or similar product, just spray around the cylinder when the engine is running. If the rpm's change while you spray at a certain area - that's where the leak is. Usually intake (the rubber thingy where the carb connects to, again i don't know the proper English word) or cylinder foot gasket (between cylinder and engine block).

About the "boost bottle", it is NOT an actual bottle! It is some sort of tank, usually sitting under the actual tank, that works as an expansion chamber for the intake. It takes in fuel/air mixture coming from the carb the moment the reeds close, and next time the reeds open this is fed into the stream, allowing for better filling and more power. This usually works only above a certain rpm range and the volume of the "bottle" and diameter/length of it's connecting hose/tube has to be precisely matched to the engine displacement and target rpm band. A bike outfitted with this system is very difficult to adjust correctly once the system is removed. Yamaha invented that one and later (before power valves came out) others used it too.

The actual bottles you have seen hanging on some bikes are either coolant overflow or improvised 2T "tanks". I put one such onto my Zundapp KS 175 because it constantly lost coolant thru the overflow. Cars have an expansion tank for coolant, too, well mine does at least. My RXZ is air cooled so - no problems with that

A recommendation if you have a new piston: During run-in (some 500 kilometers minimum) add some 2T to the gas in the tank, about a 1:75 mix. That plus your usual autolube will help the run-in process .

By the way you are talking to a guy who has over 250.000 kilometers on two-strokes under his belt and fixed them commercially for 5 years

Best regards......

Thanh

[dave_boo]

Hi

Yeah, i checked out the link that guy sent me (from thaisecondhand.com), a beautiful red RXZ..... but when i called the owner (who spoke English) the bike was already sold since last week. Bummer.

But "your" guy also contacted the one from mocyc.com (that grey RXZ that is so cheap, turned out the number works after all but he doesn't speak a word English and hung up on me) and told me that the bike can be had for 2,000 Baht but is not driveable and has NO green book.

Plus it stands around Don Mueang airport - a good 50 kilometers from where i am! Hmm, not driveable, no book/plate, 50 kilometers - no go. Altough for that money i'd buy the cylinder alone, which is supposedly a 150cc one. I SO wish i had a pickup truck!! But then - cutting off my bent rear frame and welding the part from that book-less one onto it or just cutting, bending and re-welding mine doesn't make any difference.........

So yeah, i will try to find that mystic area around National Stadium on Saturday and see if i have any luck there - if not, "cutting and welding" it will be. I really don't fancy having two bikes for i'd need to pay for another parking spot and i can only drive one anyway - my boyfriend is scared to drive "such a big bike" (and afraid of the clutch!) even tough he has a license...... and no spare room to store a dismantled RXZ A spare engine, yes, but no more

About your NSR's problem, you said it idled at 8.000 rpm - doesn't look like a carb problem to me, more one of "false air" (don't know the correct English words), that is when the engine sucks in air beside the carb, such as thru a damaged cylinder foot gasket, damaged/porous intake seal or similar. If yopu can get hold of a can of "Start Pilot" or similar product, just spray around the cylinder when the engine is running. If the rpm's change while you spray at a certain area - that's where the leak is. Usually intake (the rubber thingy where the carb connects to, again i don't know the proper English word) or cylinder foot gasket (between cylinder and engine block).

In the States, whenever air enters where it's not supposed to we simply call it an vaccum leak. This can be in the intake, the carburetor, head gasket or where ever. I doubt that a leak in your bottom cylinder gasket would cause the syptoms he's stating, since the piston should not travel that far (if it did, what would stop it from coming out of the cylinder bore and rattling around in the crank case--engine block!). You're correct about finding the problem; spray small squirts around the carb first, than the base of the carb (don't know if it mounts directly to the cylinder head or not), and than around the TOP gasket. Any surges will quickly tell you where the problem is. Of course, just because you find one place on the carb that makes it surge doesn't mean that you shouldn't keep going on and try and find other places.

About the "boost bottle", it is NOT an actual bottle! It is some sort of tank, usually sitting under the actual tank, that works as an expansion chamber for the intake. It takes in fuel/air mixture coming from the carb the moment the reeds close, and next time the reeds open this is fed into the stream, allowing for better filling and more power. This usually works only above a certain rpm range and the volume of the "bottle" and diameter/length of it's connecting hose/tube has to be precisely matched to the engine displacement and target rpm band. A bike outfitted with this system is very difficult to adjust correctly once the system is removed. Yamaha invented that one and later (before power valves came out) others used it too.

So basically it's an airbox that's after the carb? That's pretty ingenious; and as you state, much more elegant than other solutions.

The actual bottles you have seen hanging on some bikes are either coolant overflow or improvised 2T "tanks". I put one such onto my Zundapp KS 175 because it constantly lost coolant thru the overflow. Cars have an expansion tank for coolant, too, well mine does at least. My RXZ is air cooled so - no problems with that

A recommendation if you have a new piston: During run-in (some 500 kilometers minimum) add some 2T to the gas in the tank, about a 1:75 mix. That plus your usual autolube will help the run-in process .

By the way you are talking to a guy who has over 250.000 kilometers on two-strokes under his belt and fixed them commercially for 5 years

I didn't know that you had commercial experience on two-strokes; I have been thinking about getting a NSR--just don't tell my CBR 150R, I think the shock would be bad for it. Would you be adverse to looking it over (mostly motor wise) since my experience with two-strokes consists of my years 14-16 with a Motobecane and a weed-whacker...those tiny two-strokes that are on the end of a cable fed pole that you use to trim grass?

Best regards......

Thanh

[MaiChai]

I think I can help you out with a pickup/storage/Don Meung if you want to buy this bike. I need to get an early night and will write a longer post tomorrow. I am regularly transporting bikes in the back of my pickup so can easily help you out, and I am renting a house in N Bangkok (Latprao) if you need somewhere to store it for a while. Once you are finished with it, I am sure you can dispose of what you don't need on mocyc.com. If it has a rear brake caliper I would be interested

[MaiChai]

Insomnia; can't sleep.

I had the NSR running up to 8000 rpm; I wanted to see if the build was solid, so revved it up to test it. Its a long story regarding this: the gf's younger brother came to stay and he works in a bike shop when not at school and supposedly has been fixing bikes since he was 15 (now 17). Anyway I told him I had serviced the carb with a Honda spares kit, and the bike was working fine with the new spares. He insisted in putting back the old bits and could not start it. I then pulled the choke out and got it started. So turns out the spring in the choke from the spares kit is a little over sized and doesn't keep the choke out (he did not replace this incidentally). I then decide to put the new bits back, and could not start it (its almost starting); I think the second carb build has a problem and I need to take it apart again. I also found his knowledge somewhat lacking; for example he did not know batteries have acid in them (he said put water in a new battery); well its not called a lead-acid battery for nothing. Also he did not know how to remove the pin that holds the float in the carb, so he hasn't ever taken a carb apart before? Unfortunately young men can be arrogant and think they know everything? I checked the NSR compression before starting it; seemed pretty good vacume/pressure when putting my thumb over the spark plug hole.

Thahn, you know you can hire people with pickups or trucks to do work for you; for example to go and get the bike once you have seen it and are sure you want to buy it? Ask your partner about this. If you want the bike, give the guy 500 baht as a holding deposit and then the remainder when you pick it up?

My TZR does have a box connected to the rubber pipe between the carb and reed valves; forgot about this. Might need to check it out to see if its air tight since the bike runs out of power just before the power valve kicks in (or maybe I need to adjust the cables on the valve?). Box is quite big; maybe its too big and its not the original?

I have an NSR150 SP shop manual if anyone wants it. Its for the proarm version, but the RR version is identical, and thus you can use it for this. Would love to get a TZR150 (or even a VRR or TZM150) shop manual. Nearest I have found is the European TZR125; but only a Haynes manual (nowhere as good as the shop manuals). The power valve is set in a fixed position in this manual so no description on aligning the cables from the servo. Does anyone have a TZR/VRR/TZM manual?

NSRs are dirt cheap on mocyc.com; guess everyone is dumping them for something more economical. They are quite a big (and heavy) bike, so I guess would appeal to farangs who are more used to bigger bikes? Thais seem to prefer the LS125 or KRR if they want a cheap sports bike. I found one NSR for 3000 baht and another one for 5000 baht; both not been ridden for some time and suitable for spares. I even saw a 6 year old in pristine condition for 11,000 baht (and that is cheap for a bike like this).

dave_boo, if you decide to buy an NSR, make sure the power valve works; basically rev it up and see if the valve moves. On the Yamaha's, when you turn the ignition on the power valve moves (makes a whirling noise); sort of a switch on check/calibration. Not sure if the NSR does this since mine doesn't work! These are mega expensive to replace (5000 baht I was told; I inquired about buying one), so you want to buy a bike with a working valve (service manual also says the valve can stick due to carbon buildup, which could burn out the servo). All the regular wearing out bits are readily available at reasonable cost, and plenty of copy bits; but only bits essential to keeping the bikes moving (Thai style; power valve is not essential so no copy part) Beware of old bikes dressed up to look like newer bikes. Mine is an NSR150E, which is an early one, and this is in the green book; later ones are designated higher letters (NSR150N I came across once). Many Honda original parts are reasonably priced.

Some bad luck on the TZR tonight. Went to Pantip today, and on the way back the neutral light went out, and bike became hard to drive (but driveable and lights still working). I get it home and start looking for an electrical fault. Turns out the ignition switch had been replaced and whoever did it (bloody Somchai again!) fed the cable between the frame and the brake pipe; basically it was not free moving which is what you need regarding the steering. So when you put the steering lock on, the cable snags on the steering lock and it acts like a scissors, which tonight cut and shorted cable/s to the frame. Looks like the ignition is a dual pole switch and switches two circuits; one for the ignition and lighting and the other for power valve and cdi? So the power valve was not working and I am not sure how I managed to get home, but the bike was still working. Anyway soldered and repaired the cables, and re-routed them, and all is back to normal. Thought something was up yesterday and checked the spark plug (incidentally nice and brown in the middle oily round the thread; presumably all that 2T oil?).

Thanh, if you need any help with a pickup or storage, PM me and I will give you my number so we can talk. We are all glad you told us about your prior experience in the bike trade; now we can bug you for help!

I am also told Pra Rama 9 has bike scrap yards, but would not know where to look (JRD are down there in RCA).

Edited May 28, 2008 by MaiChai

[Thanh-BKK]

Good morning

Thank you very much for the replies First of all i want to address this "vacuum leak" issue - @dave_boo, what you replied is correct but only applying to a four-stroke engine As the two-stroke intake goes into the crank case, either thru the inlet port in the cylinder (via reed valves or without anything between) or directly into the crank case, again via reed valves or a rotating device (which again i just don't know the English word, in German it's a "Drehschieber"). The oil is mixed with the fuel and so the fuel/oil/air mix does the lubricating job on the lower con rod bearing, crank shaft side bearings, piston bolt bearing and piston itself. Since they intake via the crank case, the vacuum leak can sure happen around the cylinder foot gasket or even the engine gasket, around the crank case.

Regarding the "pickup" issue, for one i don't know how or where to find someone with a pickup to hire them, secondly this will sure cost money. I am a farang in Thailand, but that does not automatically mean i have a money tree in the garden - this is not the case. I just blew 9.000 Baht on a rain suit (the only one existing in Thailand, it seems, large enough for me - it had to be a high quality Japanese import!) and when my boyfriend finds out what i REALLY paid for that thing he's going to kill me. That is because nobody on E-Bay is willing to ship to Thailand! Then i blew another 4.50 on a power supplyfor my computer which burned out the very same day i got the rain suit (!!) and now my bank account is pretty empty. 2.000 for a junky motorbike i can afford, but rectifying a pickup to bring it here? No way, even if it's 500 Baht (which i don't think will be enough, more like another 2.000 from what i heard about those rental pickups with driver). If the RXZ is driveable i don't mind going all across Bangkok on it, license plate or not (bribe the cops at 200 Baht is still cheaper than the pickup!) but it looks like that bike is NOT driveable.

I had my boyfriend call that guy last night, and it was explained that this bike hasn't been moved in about a year. "It needs carb cleaning and there's no air in the tires". Well, i have a whole spare carb right here, and a foot pump costs 100 Baht. I will have my BF call him again today to make an appointment to look at the bike on Saturday..... if i like what i see (which i am sure i will!) i buy it. Heck, if that is really a 150cc kit on it, the cylinder alone is worth the 2.000 Baht! Altough my object of desire is the frame. Also the fork looks like a racing type fork, one can always use such parts

I guess that that bike was not exactly legally acquired by it's current owner, hence no plate/book. But as i only need bits and pieces of it, i don't really care.......

"Storage" is not a problem, definitely - if i get it to my place it will be taken apart rather immediately and i will, at next available opportunity, drive my own RXZ and that frame to the shop in Phra Khanong and have them do the frame welding (which i could do myself but have no welding machine - and those cost an arm and a leg). An engine, tank, set of side panels and a taken-apart fork i can store in my room

About the TZR, that "box" that is connected to the intake via a hose is the "boost bottle" or "YEIS" (Yamaha Energy Induction System). Swapping this to a bigger/smaller one will likely completely screw up your adjustments - see if the thing has corresponding holders on the main frame tube, if there are, it's original. It is probably set up in a way to boost the lower rpm's while the power valve kicks in on higher rpm's - on mine it's the other way round, mine works for the higher rpm's as i have no power valve.

About the NSR, those are sure wild bikes. I wouldn't mind to have one, any two-stroke in fact, however now i have gotten to love my RXZ for it's bulldozer-like qualities - that thing is dead reliable, and such simple technology.... i like them that way, the less breakable parts, the better. It has close to 73.000 kilometers on the clock now, plus an unknown number more as there was no speedmeter cable when i bought it....... and in my soi is one, same type, that recently "zeroed" it's clock - i saw it at 98.000 something one day, and a few weeks later it was at 1,000. That bike does some serious mileage.

I did indeed work "in the bike trade" for several years, mostly doing mopeds - 50 and 80 cc class. I can fix most things on a bike, the problem that i face here is the lack of quality tools. Even finding a decent set of wrenches is a lottery. Which is why i do everything at that "Somchai" shop in Phra Khanong. The guys there do excellent work on all sorts of bikes, you may want to give them a try? The owner is Chinese and speaks English well, no problem telling him what needs to be done, and they are quick, too, you can actually wait while your bike is fixed. The shop is in Pridi Banomyong, opposite soi 15.

With kind regards......

Thanh

[dave_boo]

Like I said, I'm not too hip on two-stroke technology . However, I've been investigating it, especially since I've learned the prices of NSR 150s are coming down so much. I found a Honda dealer that has a whole bunch in stock, both the single sided swingarm (SP model?) and the older dual sided swing arms. I will of course spring for the newer model. If push comes to shove, and I can only find a junker, I wouldn't be adverse to using that rear arm on my CBR 150....I'd suppose that it would improve the CBR's looks quite a bit. Alternatively, how much work would it be to shoehorn a NSR motor into a CBR?

@MaiChai:

I've heard of adding water to new batteries before. Sometimes they shipped them with just the powered acid inside because it was cheaper since they didn't weigh as much. Alternatively, some water could have evaporated out leaving the solids behind. You'd of course want to ideally use distilled water, but if it's a sealed battery you're kinda SOL.

[Thanh-BKK]

Hi

About that swing arm, it is possible (and quite likely!) that the two versions of it require a different mounting system on the frame itself, so fitting the respective other type would require a welding job - i am not sure if you are comfortable having welding done on load-bearing parts of the frame. I would NOT advise it. Looks isn't everything........ if it compromises safety, don't do it. A NSR is a cool bike regardless if it has the pro-arm or not.

Getting the NSR engine into a CBR is sure technically possible. It, too, will likely require welding for new engine mounts, however the frame stability is not affected by that. It may become icky to get the 2T tank placed, if there is no possibility you will need to run pre-mix, or do the "bottle" 2T thing. Also remember that such change must be legalized, i don't know how big of an issue that is here (where it is common to put all sorts of Toyota engines in all sorts of non-Toyota cars, it should be possible to do same with motorbikes as well).

Another question you may be able to answer: How much will it cost if the cops stop me on an unregistered bike, i.e. no license plate, no insurance, and no green book, with no working lights on a trip across Bangkok? If i'm lucky i'll get that RXZ on Saturday, but will have to drive it to my place (provided i get it to run right there with the limited tools that i have). On the picture it looks like it has neither cockpit nor a headlight. Not that i would need those items, it's just for the drive from "near Don Mueang" to Bangna.

Best regards.....

Thanh

[dave_boo]

Hi

About that swing arm, it is possible (and quite likely!) that the two versions of it require a different mounting system on the frame itself, so fitting the respective other type would require a welding job - i am not sure if you are comfortable having welding done on load-bearing parts of the frame. I would NOT advise it. Looks isn't everything........ if it compromises safety, don't do it. A NSR is a cool bike regardless if it has the pro-arm or not.

I've tried to find a clear picture of the NSR rear end to see if it was feasible. No luck. I wouldn't really want to have Somchai welding on it with a stick welder. However, if I had access to a TIG or even a TIG, I would be comfortable doing it myself. I agree with an NSR being a really cool bike, but if I'm dropping the change on a used bike I'd rather have the flashest version possible.

Getting the NSR engine into a CBR is sure technically possible. It, too, will likely require welding for new engine mounts, however the frame stability is not affected by that. It may become icky to get the 2T tank placed, if there is no possibility you will need to run pre-mix, or do the "bottle" 2T thing. Also remember that such change must be legalized, i don't know how big of an issue that is here (where it is common to put all sorts of Toyota engines in all sorts of non-Toyota cars, it should be possible to do same with motorbikes as well).

With the exception of the servo motor, how much more electronics would the NSR motor have? Would I essentially have to move over the whole wiring harness and make the connection to the various bits and bobs on the CBR 150? I'm thinking that is going to have to be the case since the charging system would need to be incorperated. This combo bike would most likely only be ridden in the country, so I doubt I would have any problems--that is if I didn't want to get it registered.

Another question you may be able to answer: How much will it cost if the cops stop me on an unregistered bike, i.e. no license plate, no insurance, and no green book, with no working lights on a trip across Bangkok? If i'm lucky i'll get that RXZ on Saturday, but will have to drive it to my place (provided i get it to run right there with the limited tools that i have). On the picture it looks like it has neither cockpit nor a headlight. Not that i would need those items, it's just for the drive from "near Don Mueang" to Bangna.

If you're going to Bang Na, stay off the Bang Na Trad Hwy. feeder road, or the Srinarkarin Rd, either right after Bang Na Trad heading toward Seacon Square or right after it heading away from Seacon. The cops love to set up road checks there. I'm not sure what the cost for not having your book and other assorted stuff is; but they busted me once, co-incidentally right there on Bang Na Trad heading toward the A&W fast food place, and charged me 1 000 Baht on the scene fine for not having my license with me. I'm sure that if you keep 500 Baht or so in your pocket that should be enough to get you through. Just plan out the route to avoid major streets!

Best regards.....

Thanh

[MaiChai]

Thanh, you like adventures If you buy it, ask the owner if he can recommend a local bike shop, then take it there and ask them to get it going enough so that you can ride it across town. Then ride it across town in the evening; not many cops are out at night getting folks (although they jumped out at Ratchada/Pra Rama 9 junction last week when the lights were red and started checking for road tax, etc; but they didn't bother with me; guess they figure a farang would be all legal, which I am). If they do get you it will just cost you money. Also later in the evening less traffic.

cbr is a sensible day to day, weave your way round the traffic bike (ideal for bkk); nsr is more of a monster and fun. dave_boo, if I were you I would just get an NSR and then have two bikes to play with.

Edited May 29, 2008 by MaiChai