150 2 Stroke Against 400cc

[lennya12threh]

I am short on money right now and have a VFR 400 and I love it and have so much fun on it.

I use it daily for travels in Bangkok and it is fine. I am actually slimmer and can fit in tighter spots than all the waves with their big ass mirrors.

I can maintain it fine and it is in good condition, but am very short on cash. I could get more work, but dont want to. Ive been pondering selling it and getting a 150 2 stroke. Save myself 50k baht. Alot for me!

But before I had a cbr150 4 stroke and theres no way the power on it would cut it after having the VFR. I love the VFR. Just how much slower would a 150 2 stroke be than my VFR. Top speed? Not too much eh? A 150 2stroke is signifigantly faster than a 150 cbr yea? Once in the high RPMs an nsr would be accelerating comparably with my VFR yea? Maybe I should just test drive one..... Once i did drive a 125cc 2 stroke honda dash, and that thing in the high rpms was a little scary. Comparable to the vfr. It was a little questioning to my vfr 400 after driving it. The little thing was fast!

If I did sell the vfr and get an nsr or tzr or whatever, i would have the 2 stroke in top condition and inspected fully. I could put alot of work into one and still save a ton of money.

Just pondering, and everyone here always has so much good input, knowledge and experience, that at this point, I am lacking.

Thanks, Lenny

[apetley]

More years than I care to remember ago my mates and I used to ride several different motorbikes, from little 125's up to 1100's.

One of my friends had a Yamaha RD125LC, a water cooled 2-stroke. He tuned it up, ported barrels and a head skim. Kept the standard exhaust as the local police were hot on noise.

His bike just about topped out at about 100 mph, 160 kph.

A friends Honda 400 was significantly better on top end but not that much better on acceleration due to the extra weight.

My concern these days would be finding a nice looking and more importantly mechanically sound 150 2-stroke.

[Yimmy]

and just as a matter of asking, how much would you be asking for the vfr?

[Kf6vci]

There was a race series in Japan where 400 cc 4-stroke bikes raced against 250 cc 2-strokes. Try find a 250 cc, even an RD 250 LC would be faster than a more modern 150 cc.

Hope you get a delicious TZR-250 with aluminium frame and razor sharp handling.

I had some fun with the RD 350. Haven't seen one over here though.

[tomartoh]

The big difference to me between my nsr 150 and previous vfr400 is in weight. i have also had a cb400 and would definitely prefer the nsr to that. the nsr is definitely lightweight and you know about speed at 180. when i used to ride big bikes back home i never particularly felt uneasy at that sort of speed. think at the end of the day depends on the riding you intend to do. i dont worry about top speed now and concentrate more on staying alive when on the bike, even so the nsr is a nice bike to ride and a lot of fun. go try one and you can pick them up so cheap. a dealer offered me only 4k for mine and it looks fantastic and goes like the furies. but no one wants them now. plenty of parts available and most local mechs can work on them

from time to time you will see 250cc advertised on thai second hand etc. forget the details but was one last week

[submaniac]

To the OP, I am ordering you NOT to sell the VFR400. You will regret it. I currently own a Yamaha TZM, an Yamaha FZR 400, and just sold my NSR150RR to another forum member. I know what you are thinking, but it's not quite the same. The two strokes 150cc bikes are capable of approaching the top speeds of some of the 400cc bikes. However, when they are at those kinds of speeds the acceleration to reach the top end is slow. Like the engine will be wailing at top RPM and the top speed is gradually moving higher and higher at 5kph increments. At above 140kph the little 150cc bikes kind of get scary. They don't weigh that much, and the tires on the bikes are fairly skinny so there's not alot of road contact. When I was doing those kinds of speeds, the bike got pretty much (at least it felt like it to me) AIRBORNE when I hit a bump on Thailand's notoriously poorly maintained roads. The difference between a 400cc and a 150cc two stroke is night and day. Yes, the 400 cc bike weighs more, and may not be as nimble as the 150cc bikes. But the ride is so much better, and the sound of a one cylinder engine wailing can't match the 'vroom' of a Japanese 4 cylinder.

The 150cc two strokes are falling out of favor with the Thai populace and the bikes can be found fairly cheap. And, since it is simple two stroke technology, they are very cheap to fix and maintain. The problem is that 95% of the two stroke bikes for sale are probably thrashed and will require alot of mechanical work to get in proper shape again.

A good 400cc bike is hard to find, and if you got one, KEEP IT. Before you sell it, try out the 150cc two strokers before you get rid of the 400cc. I tell you I thought I was happy with the 150cc's, but once I got on a 400cc bike I just could not really go back.

[lennya12threh]

To the OP, I am ordering you NOT to sell the VFR400. You will regret it. I currently own a Yamaha TZM, an Yamaha FZR 400, and just sold my NSR150RR to another forum member. I know what you are thinking, but it's not quite the same. The two strokes 150cc bikes are capable of approaching the top speeds of some of the 400cc bikes. However, when they are at those kinds of speeds the acceleration to reach the top end is slow. Like the engine will be wailing at top RPM and the top speed is gradually moving higher and higher at 5kph increments. At above 140kph the little 150cc bikes kind of get scary. They don't weigh that much, and the tires on the bikes are fairly skinny so there's not alot of road contact. When I was doing those kinds of speeds, the bike got pretty much (at least it felt like it to me) AIRBORNE when I hit a bump on Thailand's notoriously poorly maintained roads. The difference between a 400cc and a 150cc two stroke is night and day. Yes, the 400 cc bike weighs more, and may not be as nimble as the 150cc bikes. But the ride is so much better, and the sound of a one cylinder engine wailing can't match the 'vroom' of a Japanese 4 cylinder.

The 150cc two strokes are falling out of favor with the Thai populace and the bikes can be found fairly cheap. And, since it is simple two stroke technology, they are very cheap to fix and maintain. The problem is that 95% of the two stroke bikes for sale are probably thrashed and will require alot of mechanical work to get in proper shape again.

A good 400cc bike is hard to find, and if you got one, KEEP IT. Before you sell it, try out the 150cc two strokers before you get rid of the 400cc. I tell you I thought I was happy with the 150cc's, but once I got on a 400cc bike I just could not really go back.

I was thinking more today and yesterday while driving it around bangkok and was thinking the same thing. I cant give it up.

I do have a good vfr. Fully legal. I payed 65k for it but think I should have payed less because it had so many issues. 35k later after a new engine was put in, re built, new rad and some other smaller parts within the cooling system and front suspension were swapped, it seems fine and I feel confident riding it.

Ive taken it to cambodia, pattaya and the works and no problems there.

I will have to test drive a nsr "na."

[thaicbr]

Lenny. Keep the bike. just go on a cost cutting exercise with every thing else.

[ray23]

I've owned a 150 sit up properly you have a 160 bike, that being said once yuo do that it will pass everything but a ga station, Fun though. Responsive easy to handle.

I hve a 400 Dragstar now my 150 would eat fro breakfast. But it's heck of a lot more comfortable. Can

t commen on the VFR never had one.

[t.s]

edit: sorry just reread and saw you are talking about the 150rr not the 250. short answer, dont do it. the 150 feels like a toy compared to the 400, the brakes are crap, riding position odd and you simply dont want one. it is difficult to belive the 250 and 150s even share the same name. one is a real bike, the other is a very low budget copy.

i own both a vfr 400r and an nsr 250rr they are very comparable.

the nsr is much easier in traffic and very well mannered until you start to wring out the throttle. it then becomes very quick, and i would say it is faster off the line than the vfr.

a road trip with both through the south proved the nsr could easily keep up with the vfr in almost all situations, top speed isn't that different. the vfr was flawless, but the two stroke stared to flag after 1000+ km. in the long run the vfr is easier to maintain with the exception of battery charging and known rectifier issues these bikes have. the nsr however is a 2 stroke and can be quite finicky if you dont maintain it frequently especially if the auto lube is off and the plugs get fouled. the nsr is also a kick start and may not like cooler mornings or starting after a few days down time.

the nsr has a much lighter clucth and is much more easy to drive in bangkok traffic.

i highly doubt an nsr 250 rr would save you any money, and thais are becomeing less andd less willing to work on them.

the key difference is the 2 strokes lack of engine braking and higher center of gravity. it is also considerably lighter. i like it much better in bangkok. it also is not as bad a fireball as the vfr, which can get scalding hot.

[Gunslinger]

Lenny. Keep the bike. just go on a cost cutting exercise with every thing else.

Lenny, I agree with thaicbr, it sounds as though you're happy with the 400, and with the transfer from one bike to another, you will lose money one way or another. Now to praise the 2 strokes, I am a 2 stroke nut, MX'er for many years in USA, and now too old and fat to do it in the dirt, so I get my kicks on the road now, I have an '04 Kaw KR150ZX in mint cond. I picked up in Pattaya for 45,000 baht with only 3km on it. I have a posting for performance tips and shops, not because it is slow, I just want it to be all it can be. So I just wanted to tell you you're right about a 2 stroke 150 being as much fun as a 400. I rented a lot of big bikes here in Thailand before, and for me top speed is something you do just to see what it'll do, then most of the time it is more important how the bike can be handled at slow speeds and in traffic. I bought my bike a year ago when I heard they were banning 2 strokes, I wanted to get one before they were unobtainable. I have more fun on my 2 stroke than the big bikes I rented, such as Midnight Star, R1, Blackbird, Buell, V Max, etc. and as a bonus the 2 strokes are much cheaper.

[lennya12threh]

Lenny. Keep the bike. just go on a cost cutting exercise with every thing else.

Lenny, I agree with thaicbr, it sounds as though you're happy with the 400, and with the transfer from one bike to another, you will lose money one way or another. Now to praise the 2 strokes, I am a 2 stroke nut, MX'er for many years in USA, and now too old and fat to do it in the dirt, so I get my kicks on the road now, I have an '04 Kaw KR150ZX in mint cond. I picked up in Pattaya for 45,000 baht with only 3km on it. I have a posting for performance tips and shops, not because it is slow, I just want it to be all it can be. So I just wanted to tell you you're right about a 2 stroke 150 being as much fun as a 400. I rented a lot of big bikes here in Thailand before, and for me top speed is something you do just to see what it'll do, then most of the time it is more important how the bike can be handled at slow speeds and in traffic. I bought my bike a year ago when I heard they were banning 2 strokes, I wanted to get one before they were unobtainable. I have more fun on my 2 stroke than the big bikes I rented, such as Midnight Star, R1, Blackbird, Buell, V Max, etc. and as a bonus the 2 strokes are much cheaper.

Well Im having so much fun with this vfr, but me and my girlfriend really need money now, and plus i feel so in love im afraid of dieing and want to be safe. Yak ben neetsaidee! Sometimes I love to rip down phechaburi, srinakarin, etc, and blow by people, but sooner or later i will have an accident. Already had a couple close calls of course. It feels better to drive conservatively, and an NSR is still quick off the line and has power. Maybe not as great on the highway, but even then sooner or later I will encounter more of those thai teens doing u-turns on the way to pattaya, and going 180, die. Where as going 120-140 will make the difference there.

I figure I can come out with an extra 40-50k after selling the vfr and downgrading, which is two months salary for me and alot of money for me.

I bought it for 65k, which after having it for 2 weeks, thought was a bit steep because it couldnt stop overheating because of cooling problems, but now no problems. Ive put at least 35k into it, rebuild new second hand engine (jap import) installed. Sold the old one. New parts within the cooling system (rad, cap, tubes) , front suspension rebuilt, with new sealers. The bike has been stripped down and viewed by the mechanic behind seacon square, who only does big bikes, primarily the 400s.

Now no problems.

Thinking of selling for 70k. Has the tax all up to date, insurance, and the green book which when transfered into my girlfriends name went through the Land of Transportation computers/system. Can transfer at the land of transportation, so I believe it is a fully legitimate book.

[OzMick]

I'm a bit of a pack rat and have accumulated a few bikes, including a Katana 400, NSR's in SP and RR, and a Repsol Dash. Since I picked up the Katana, the NSR's are collecting dust. They are great fun for short rides, especially in the hills, but over any real distance they are just a pain in the buttocks. The 400 is so much more comfortable for distance it's the only choice - since I've had it I've been to Sungai Kolok, Chiang Mai and Nakhon Phanom (yes, I did put it on the train for part of the trip up to NP).

Around town, the Dash gets the vote because of it's manouverability, with 2-stroke zing.

No, the NSR's are not for sale.

[OzMick]

I'm a bit of a pack rat and have accumulated a few bikes, including a Katana 400, NSR's in SP and RR, and a Repsol Dash. Since I picked up the Katana, the NSR's are collecting dust. They are great fun for short rides, especially in the hills, but over any real distance they are just a pain in the buttocks. The 400 is so much more comfortable for distance it's the only choice - since I've had it I've been to Sungai Kolok, Chiang Mai and Nakhon Phanom (yes, I did put it on the train for part of the trip up to NP).

Around town, the Dash gets the vote because of it's manouverability, with 2-stroke zing.

No, the NSR's are not for sale.

[lennya12threh]

No, the NSR's are not for sale.

You SOB.

Well I don't plan on any long trips soon. My girlfriend is not comfortable on the back of a motorcycle. "Jep!" Plus her family is scared of it.

[MaiChai]

My NSR RR has been sitting in bits since I put a new cylinder liner/piston in it (last one siezed and I got a crack in the liner). Mine is the older single square headlight one with the square rear light cluster (NSR150E). Looks a bit like the KRR. I saw a spruced up one the other day and it looked really nice so think I will get the thing going again

Interesting thing is the new liner has a huge exhaust port; maybe twice the size of the original, so it looks like I got a power upgrade too

[MaiChai]

Got my NSR running now. Had to tweak the carb: reduced the float level, replaced the main jet with one that has a much smaller hole, replace the needle valve with one that is wider lower down the taper (all this meaning less rich fuel mix). Now it starts easily and revs right up to 8000rpm with no probs. Will put the tank back on tomorrow and give it a spin. Wippee

[lennya12threh]

Got my NSR running now. Had to tweak the carb: reduced the float level, replaced the main jet with one that has a much smaller hole, replace the needle valve with one that is wider lower down the taper (all this meaning less rich fuel mix). Now it starts easily and revs right up to 8000rpm with no probs. Will put the tank back on tomorrow and give it a spin. Wippee

Well i now have an nsr. My vfr is for sale.

The nsr seems good. I test drove 3 and the one i got seemed to have the smoothest engine, but still feels a little shaky of course. Its 12 years old and is a 2stroke. Nothing like the smooth endless tourque behind the vfr .

Im curious though. What are some affordable things i could do to make her breath easier, make her like new again, or increase performance? It is a fun little thing. I have to go the mechanic tomorow anyways for some minor touch ups. It sure looks beautiful and shiny though!

Also, id assume im to use just gasohol with the nsr, and not benzyne like the vfr. And where do you get oil for it?

[MaiChai]

2 strokes hate gasahol. Put some in my TZR by accident and it sounded like a bag of nails. Stick to the benzine 91.

Did you check if the power valve works? Often they don't; I mean the servo burns out or siezes. Mine doesn't work, but thats least of my worries for the moment. If you rev it up you should see the power valve move.

PS: If you want the shop manual, let me know I have the pro arm one (RR is pretty much the same).

[lennya12threh]

Ps. I am no mechanic, so currently anything that will be done in the near future will have to be done by someone I have paid.

Yea the manual would be nice!

The power valve? The RC valve?

Yea, I really need the manual. I dont even know where the power valve is located. I just bought it today and drove it home. Used my vfr to go out tonight because the nsr has no fuel left and i dont have any oil for it yet. not sure what to put in it. this is my first 2stroke.

[MaiChai]

I have the owners manual for the SP too. This is what it says about 'Petrol containing alcohol':

If you decide to use petrol containing alcohol (gasohol), be sure it's octane rating is at least as high as that recommended by Honda. There are two types of "gasohol": one containing ethanol, and the other containing methanol. Do not use petrol that contains more than 10% ethanol. Do not use petrol containing methanol (methl or wood alcohol) that does not also contain cosol-vents and corrosion inhibitors for methanol. Never use petrol using more than 5% methanol, even if it has cosolvents and corrosion inhibitors.

So I would stick with the 91 benzine. My TZR likes the Shell Power Bensin too, so that should be ok.

From an ethical point of view I think any gasohol is wrong. I mean growing crops for very cheap prices to make fuel. Land should be used to make food, and the folks that do this are entitled to a decent level of income from the crops they grow. Just my point of view.

RC valve is on the cylinder; It looks half moon shaped and has a cable at either end to move the valve. It should move (open the valve) when you rev it. Basically makes your exhaust port larger at higher revs and thus gives more power. You can use the bike without this working, in which case its set to a small opening. It means less power (but it also means better fuel economy?). Mine never worked. A guy on mocyc.com sells second hand ones. They are very expensive new (5000 baht). The shops at Sapan Kwai used to sell replacement motors (you take the servo apart, lubricate it, check for no broken cogs, etc, and replace the motor). However these shops seem to be loosing interest in providing parts for these old bikes. Lots of these bikes getting scrapped at the moment so it should be easy to get 2nd hand parts, if you can negotiate a reasonable price Look on mocyc.com for parts (you may need to call someone and get a Thai friend to ask "do you have this part for bike X and how much do you want for it").

As a side issue, I had to visit the BiB at Suttisan the other week and they had loads of impounded/crashed NSRs. I guess folks did not want to pay the tea money to get them back and the Thais are not interested in them anymore (better to have a feminite Fino that a macho sports bike?). Wonder if you could off some baht for some spare parts?

[MaiChai]

Reading a bit further on in the owners manual:

Fuel system damage or engine performance problems resulting from the use of fuels that contain alcohol is not covered under the warentee. Honda cannot endorse the use of fuels containing methanol since evidence of their suitability is incomplete.

This means you cannot trust what they have put in the fuel, or it may be ok, but later bits are rotted away in your carb, or they may change what is in the fuel at any time. Thus use benzine.

Its interesting to note that the Japs used fuel derived from trees in the 2nd world war as their fuel supplies dried up.

[lennya12threh]

Can I see the valve without taking the bike apart? I dont have any tools.

Tomorrow I am having some general service done on it at Honda. I bought some engine oil from Honda.

Besides the valve, what are some other common occurances or conditions that can limit performance?

[dave_boo]

Lenny, it's right on your exhaust. When you turn the key to the on position you should be able to hear/feel the motor go through a self test. Another way to tell is if there's a huge kick in your pants increase in power at higher RPMs...

[thaicbr]

Lenny. Talk to Thahn he is a a 2t guru. most of the time when he niffs a 2t thread he's on it like a rat up a drainpipe.

[MaiChai]

Been busy fixing up the NSR before I take it for a test ride. Signal switch needed an overhall and there was a bad connection on the headlight (poorly crimped). Tubes were missing for the crankcase rebreathers (Honda put them in for a reason, right?).

My TZR goes through a self test when you switch it on; you can hear the servo whirl. I did not know if the NSR does this too as the servo on mine does not work; dave boo says it does so I take his word for it! The valve is on the right hand side of the cylinder. You can't miss it! If it doesn't work, no big deal, its still a B52 bomber of a bike! Huge, powerful, fuel guzzling with smoke pouring out of the back!

Be a bit careful about taking it to Honda for fixing it; you could end up with a large bill. Make sure you discuss anything expensive that needs doing before they go ahead. There are cheaper ways of doing things than putting brand new (and expensive) parts from Honda on an old bike. Before I fixed up my carb, I got Honda to price up new jets; we are taking small bits. They quoted 1200 baht; I told them for that I could get two new copy carbs (about 600 baht each). My TZR got a new copy carb and its the best thing I did for it (and at 600 baht cheap). In the end, for the NSR, I just used an assortment of bits I had collected from carb refurb kits; I had two kits plus a third I bought for 70 baht. These carb kits often don't have the right bits in them so its a case of comparing old with new and if they are the same, then change them over. In my case I had a wider needle valve and a smaller main jet that I substituted in, which got my bike working again.

User manual says use 10W40 oil, so best pay a couple of baht more for decent oil that specifies this (the cheaper doesn't nor does the generic Honda one, which is designed for Waves and the like).

The shop manual has a huge maintenance section. This will give you an idea of what needs doing. Change the plug (and make sure its the right one), change the oil (gear shifting will be better). Check the rc valve and exhaust for carbon buildup (I regularly do my TZR; the valve on this is better designed than the NSR in my opinion). Clean the fuel filter just below the fuel cock. The fuel filter is not great it does not filter as well as more modern bikes and all the Bangkok soot gets into your carb. I bought a cheap inline filter, cut it open, took the filter mesh out and put this in the NSR filter. Now I don't have to clean the carb out regularly. You could put this filter inline between the fuel cock and carb. Check brakes/bleed a little. Check lights. Check correct operation of brake light. Check lights/bulbs. All the normal stuff really. With a 2stroke, not much to go wrong really. Just make sure it smokes.

Two things to be wary about. Its a known thing that running a 2stroke at the same revs for long periods can cause a piston sieze (see this). Piston sieze can occur if the piston is starved of 2stroke oil (hence you want to see smoke pouring out of the back). This NSR of mine had a piston sieze on me. Bottom line is always be looking out for it, and when it happens pull in that clutch! Luckily I was going slowly and was awake enough to pull in the clutch! One moment was the sound of my engine and the next a thud and silence! Sometimes you can just unstick the piston and put it back!

[lennya12threh]

LoL. All this servicing sounds intimidating to me. I have no tools, but if I did Im sure I could it with the manual.

The RC valve does work. I found it on the right side.

Thanks.

[MaiChai]

lennya12threh, I sent you a PM with a link to download the NSR SP shop manual and also the owners manual. Did you get the PM?

If anyone else wants these, please PM me.

You can use this shop manual for the RR too. Both are the same apart from the proarm, the carb is a later revision and other minor differences. Engine is essentially the same, but some differences on the RC valve, etc.

[lennya12threh]

lennya12threh, I sent you a PM with a link to download the NSR SP shop manual and also the owners manual. Did you get the PM?

If anyone else wants these, please PM me.

You can use this shop manual for the RR too. Both are the same apart from the proarm, the carb is a later revision and other minor differences. Engine is essentially the same, but some differences on the RC valve, etc.

Hey. yea I got it but havent gone online much lately.

Yea I went to Honda because the shocks need to be rebuilt (there spilling all over the front brakes making braking very limited) and the chain/the thing the chain is mounted on is loose and wobbly (and makes a nasty sound). So far the bill for that is 3000-4000 baht depending upon what it looks like once they take it apart.....

I am not a mechanic and I dont trust the average shop. I have no tools. Is there a better way. Pretty soon this will be 25,000 baht nsr. dam_n....

Also theres an oil leak coming from the engine.... Dont want to look at it. I can drive fine and seems to run good and fast. I think I should just pretend it isnt there.. LoL No, I cant do that......

As well, two times already Honda has told me to come back again and again because they cant do it yet... Parts hvent came. Its been like 7 days... Maybe this is a good thing if anyone has a beter idea....

[Datsun240Z]

I'm getting 23 HP here out of a 70cc LC engine. Top that.