Nsr150Rr Overheating & Possible Rc Valve Problem

[saviorsoul0872]

So I picked up a NSR150RR a couple of weeks ago. I've had a lot of work done for pretty cheap and eliminated most of my problems. However my NSR doesn't have ANY power from about 8500RPM-11000RPM and USUALLY won't even exceed 9000RPM. It acts as if there is a rev limiter almost and cannot pass it. After reading about RC Valves I decided to see if mine was working properly. I observed my RC valve and it was functioning, but after looking at a friend's NSR realized that mine was functioning in the opposite way. His however has power in the upper bands and he can redline.... Is it possible that my RC Valve is functioning backwards?? or is the design different from that of my friends NSR? *eg. do different years function differently??

MINE idles on L and moves to H upon reving and around 6000-7000 moves back to L....

my FRIENDS idles on H and moves to L upon reving and around 6000-7000 moves back to H.....

Is it possible my RPM problems is due to my RC Valve SOMEHOW being tuned backwards.... Its baffling AND rather annoying the hell out of me.

Also while driving in traffic both my friends and my NSR overheat excessively to burning our balls if we don't find a stretch of land to drive consistantly on to have air flow over the radiator. Is this a common problem with NSRs that is caused by an old thermostat or old radiator? My coolant is clean, radiator is full, and no leaks because the coolant level does not go down.

So far my bike has undergone receiving a new oversized piston, oil change, new air filter, cleaned the carborator, new front & rear sproket (smaller), new chain, new front a rear tires, and *previously has been lowered I believe because mine sits hella lower than my friends and I scrape on speed bumps if I don't slow to a crawl.

Also looking for a cluster mines shot. The needle inside the speedometer broke off inside, and the high beams light doesn't light up (minor but annoys the hell outof me).

Any comments, suggestions, experience, knowledge, and wisdom would be greatly appreciated!

[johng]

Mine was getting very close to the red on the temperature gauge,especialy sat at the lights

I changed the coolant but it didn't help.

so I ended up taking the radiator off and filled it with a 50/50 mix of white vinegar and distilled water

left it overnight.

next day encouraged to see that no holes had appeared I filled it with 100% vinegar

and left it to cook for a few more hours hours.

then gave it a good long flush out with just plain water I found gently knocking it on the floor in various orientations released more crud

after a few hours of this I was knackerd so put the rad back on the bike to try it out.

Now the temp gauge hardly goes above the midway mark.

Although the workshop manual mentions a thermostat there isn't one on the NSR. ( well not on mine RR version )

You could also check/change the radiator cap if it isn't keeping the sytem presurised coolant can overheat.

Power valve on mine is stuck in the Hi position its ridable so I leave it alone untill its time to service the top end.

[poanoi]

On the odd chance you want power, buy a big bike. cubic is king

[VocalNeal]

MINE idles on L and moves to H upon reving and around 6000-7000 moves back to L....

my FRIENDS idles on H and moves to L upon reving and around 6000-7000 moves back to H.....

Sadly i don't have mine anymore but I have a 250 downstairs which I'm too lazy to check.

BUT it sounds as if the cables from the servo to the R/C valve are reversed.

From memory the cam should turn clockwise, towards the front of the bike, .when the bike is between 7000-8000 (could be 500 rpm lower? ) when idling it moved anti/counter clockwise,

When you turn on the ignition on it should move anti/counter clockwise.

Overheating. What JohnG said.

All is explained in the manual https://docs.google.com/file/d/0B0fPe4feWkfeYWQ0OTM1NzYtZmFhYS00YjBmLWFhMjgtNzcyMjI5NTBmYWNh/edit?hl=en

[saviorsoul0872]

On the odd chance you want power, buy a big bike. cubic is king

Well I'm a 22 year old US Veteran living here on my GI Bill. I only get $1368USD a month so buying a 80,000baht bike isn't probable. Furthermore, its my first bike and cost me 13,000baht and would more than suffice if it ran correct.

[saviorsoul0872]

Mine was getting very close to the red on the temperature gauge,especialy sat at the lights

I changed the coolant but it didn't help.

so I ended up taking the radiator off and filled it with a 50/50 mix of white vinegar and distilled water

left it overnight.

next day encouraged to see that no holes had appeared I filled it with 100% vinegar

and left it to cook for a few more hours hours.

then gave it a good long flush out with just plain water I found gently knocking it on the floor in various orientations released more crud

after a few hours of this I was knackerd so put the rad back on the bike to try it out.

Now the temp gauge hardly goes above the midway mark.

Although the workshop manual mentions a thermostat there isn't one on the NSR. ( well not on mine RR version )

You could also check/change the radiator cap if it isn't keeping the sytem presurised coolant can overheat.

Power valve on mine is stuck in the Hi position its ridable so I leave it alone untill its time to service the top end.

THanks I will try that this weekend! Hopefully that'll work out well! Do you choose vinegar because its a acid/base and its "eats" the crud away?

[saviorsoul0872]

MINE idles on L and moves to H upon reving and around 6000-7000 moves back to L....

my FRIENDS idles on H and moves to L upon reving and around 6000-7000 moves back to H.....

Sadly i don't have mine anymore but I have a 250 downstairs which I'm too lazy to check.

BUT it sounds as if the cables from the servo to the R/C valve are reversed.

From memory the cam should turn clockwise, towards the front of the bike, .when the bike is between 7000-8000 (could be 500 rpm lower? ) when idling it moved anti/counter clockwise,

When you turn on the ignition on it should move anti/counter clockwise.

Overheating. What JohnG said.

All is explained in the manual https://docs.google....YWNh/edit?hl=en

Amateur bike mechanic here.... So does that mean I should reverse the cables? or reverse wires on the motor? or readjust?

[mania]

On the odd chance you want power, buy a big bike. cubic is king

Well I'm a 22 year old US Veteran living here on my GI Bill. I only get $1368USD a month so buying a 80,000baht bike isn't probable. Furthermore, its my first bike and cost me 13,000baht and would more than suffice if it ran correct.

As a side note, folks who never raced 2 strokes may not realize what they are capable of.

While the adage that cubic is king is basically true, that is when comparing apples to apples.

Folks who have raced two strokes are actually spoiled by impressive power to weight ratios

Edited October 15, 2012 by mania

[VocalNeal]

MINE idles on L and moves to H upon reving and around 6000-7000 moves back to L....

my FRIENDS idles on H and moves to L upon reving and around 6000-7000 moves back to H.....

Sadly i don't have mine anymore but I have a 250 downstairs which I'm too lazy to check.

BUT it sounds as if the cables from the servo to the R/C valve are reversed.

From memory the cam should turn clockwise, towards the front of the bike, .when the bike is between 7000-8000 (could be 500 rpm lower? ) when idling it moved anti/counter clockwise,

When you turn on the ignition on it should move anti/counter clockwise.

Overheating. What JohnG said.

All is explained in the manual https://docs.google....YWNh/edit?hl=en

Amateur bike mechanic here.... So does that mean I should reverse the cables? or reverse wires on the motor? or readjust?

Change the cable over at the RC valve pulley but you will have to readjust them as in the manual I gave the link to. take out the slack.. No more difficult that tightening the brakes on a bicycle almost the same fittings.

[English_M_in_Bkk]

Could be that your carb is knackered and you need a new one, or a good quality second hand one.

I had the same problem with my RVF - no power in certain bandwidths wouldn't go over 9,000 RPM and overheating. Had new carbs put in and has been sweet ever since.

Get a mechanic to really check your carbs for you, for leaks etc.

[johng]

THanks I will try that this weekend! Hopefully that'll work out well! Do you choose vinegar because its a acid/base and its "eats" the crud away?

I looked at some radiator flush mixes sold at various places..but none of them listed the ingredients and they where expensive

for a cheap charlie like me ( 300+ baht ) vinegar and distilled water less than 100 baht.

also I read that some of the commercial flushes where very strong and could cause leaks.

The vinegar is acidic and does eat the crud/limescale (and eventually everything ) but still needed quite vigourous shaking/knocking to get the flakes out of the very thin tubes in the rad.

If your feeling lazy you could take the rad to a car aircon service place and let them do it, they may even have an ultrasonic cleaning bath.

[saviorsoul0872]

MINE idles on L and moves to H upon reving and around 6000-7000 moves back to L....

my FRIENDS idles on H and moves to L upon reving and around 6000-7000 moves back to H.....

Sadly i don't have mine anymore but I have a 250 downstairs which I'm too lazy to check.

BUT it sounds as if the cables from the servo to the R/C valve are reversed.

From memory the cam should turn clockwise, towards the front of the bike, .when the bike is between 7000-8000 (could be 500 rpm lower? ) when idling it moved anti/counter clockwise,

When you turn on the ignition on it should move anti/counter clockwise.

Overheating. What JohnG said.

All is explained in the manual https://docs.google....YWNh/edit?hl=en

Amateur bike mechanic here.... So does that mean I should reverse the cables? or reverse wires on the motor? or readjust?

Change the cable over at the RC valve pulley but you will have to readjust them as in the manual I gave the link to. take out the slack.. No more difficult that tightening the brakes on a bicycle almost the same fittings.

That solved the problem. I can go to 11,000+ through all gears except 5th. 5th still sticks at about 9000 some reason (Think it sitll needs adjustment, but at least it functions the correct way now)..

Going to try the vinegar idea cleaning out the radiator next to hopefully solve that problem probably get to that this weekend.

Thank you everyone for helping out!

[saviorsoul0872]

On the odd chance you want power, buy a big bike. cubic is king

Well I'm a 22 year old US Veteran living here on my GI Bill. I only get $1368USD a month so buying a 80,000baht bike isn't probable. Furthermore, its my first bike and cost me 13,000baht and would more than suffice if it ran correct.

As a side note, folks who never raced 2 strokes may not realize what they are capable of.

While the adage that cubic is king is basically true, that is when comparing apples to apples.

Folks who have raced two strokes are actually spoiled by impressive power to weight ratios

Not sure if its "accurate" but I look at it like my 150 runs like a normal 4stroke 300cc bike because unlike making power every 4th stroke we make 100% more power per CC because we make power every 2nd stroke. I fell in love with my NSR first time I rode it, then I started getting pissed at the problems, but after getting everything (mostly) fixed and seeing even MORE power with the RC Valve functioning the correct way I'm impressed.... I mean its no Ninja, but for $400 seriously can't beat it....

[mania]

Not sure if its "accurate" but I look at it like my 150 runs like a normal 4stroke 300cc bike because unlike making power every 4th stroke we make 100% more power per CC because we make power every 2nd stroke. I fell in love with my NSR first time I rode it, then I started getting pissed at the problems, but after getting everything (mostly) fixed and seeing even MORE power with the RC Valve functioning the correct way I'm impressed.... I mean its no Ninja, but for $400 seriously can't beat it....

Not exactly but it is a fact 2 strokes can make incredible peak HP per CC

Look also at the HP figures & then look at the weight & what you end up with is very impressive power to weight ratios

True that two strokes lack torque in comparison but for folks who like to row the gear box it is not a problem at all

staying on the pipe.

Glad to hear your sorting your bike & hope you enjoy it.

Broke my heart to see 2 stroke GP go away as I loved it.

Heck as a kid I was racing 125,250 & open class 2 strokes

The 125 I rode way back then ( decades ago ) had as much or more HP once ported than today's CBR250

& weighed half as much.

Check specs on a 2 stroke 250 like a Honda RS250R

Edited October 23, 2012 by mania

[VocalNeal]

Check specs on a 2 stroke 250 like a Honda RS250R

Or even a NS400R

[karlos]

Here you go, 4stroke v's Two stroke

Honda VFR400 (NC30) v Suzuki RGV250

Happy days

Lol would help if i posted the link

Edited October 24, 2012 by karlos

[yankee99]

Here you go, 4stroke v's Two stroke

Honda VFR400 (NC30) v Suzuki RGV250

Happy days

Lol would help if i posted the link

Never saw a two stroke that clean. Everyone here smokes like a dirty chimney .

[mania]

Never saw a two stroke that clean. Everyone here smokes like a dirty chimney .

That is down to their mixture being off & using a separate oil tank relying on the

proper mix via the pump etc.

Race bikes use premixed fuel.

The oil is added to the gas before filling

Also using a good 2 stroke oil like Bardahl

[VocalNeal]

Never saw a two stroke that clean. Everyone here smokes like a dirty chimney .

That is down to their mixture being off

Upcountry here it is like Indonesia. Where someone on a 2T bike pulls up at the pump. Attendant get bottle of oil measures out some oil, dumps it in the tank and then asks "How much benzine do you want"!

[bbradsby]

OP, to fine tune it, check the power cable alignment only after adjusting the throttle cable slack and the oil pump calibration. maybe then you'll find your redline in top gear... wait, did you say you went to a larger rear sprocket? That would kill your top end right there, as wind resistance overcomes your 'overdrive' sixth gear.

Edited October 25, 2012 by bbradsby

[VocalNeal]

...as wind resistance overcomes your 'overdrive' sixth gear.

If the OP is 6 ft tall and as has been stated has a smaller sprocket on the rear then that maybe the cause. Aerodynamics.

But max tourque is at 10,000 and max power at 10,500, so it should pull 10,000?

I wonder if the exhaust has been cleaned out?

[bbradsby]

ya, these bikes are fast for a 150 machine, and easily embarrass the 4stroke 250's, but at some speed wind drag defeats all bikes... for these peashooters, it doesnt take much.

[monty]

Yeah, sits in the gearing.

For maximum speed gearing has to be exactly right, too high and your engine falls short to fight wind resistance reaching top speed, too low and you'll red line with power to spare at a lower speed.

Obviously with age and wear/tear engine output changes, and so will be optimum gearing.

Additionally, people using the bike as a daily driver might opt to change the gearing so as to lower revs at say 120 km/h for better fuel economy and lower wear.

Sent from my GT-I9001 using Thaivisa Connect App

[johng]

Although the workshop manual mentions a thermostat there isn't one on the NSR. ( well not on mine RR version )

You could also check/change the radiator cap if it isn't keeping the sytem presurised coolant can overheat.

In fact I'm wrong the NSR 150 SP doesn't have a thermostat ( no housing in the cylinder head)

but the RRp version

and 125 version have the housing for a thermostat.

haven't found a diagram for the RR and RRW versions yet.

[mania]

Anyone who works on bike has to Love

the simplicity of the top end of a 2 Stroke engine

Those diagrams really bring that home.