Did I mention cables for the RC servo are old to... I did adjust it to the H when idle.... 

The bike should still rev to the (near) red line even without the
"power valve" being operational,
Its purpose is to try and even out the delivery of power from the engine (power band) without it most power is produced in a narrow rev range (normally at the high end)

150cc 2 stroke manuals  parts and service for NSR and others.

 

https://drive.google.com/open?id=0B1XIFy-iDDDfcDI0UXZrakNLaGc

On 02/11/2017 at 12:44 PM, AllanB said:

 

 

On 02/11/2017 at 1:05 PM, Tioga246 said:

Millage very high on this bike.... Cable on choke abit worn bit it works.... Another thing I did check... And there is no filter in my box... 

 

On 02/11/2017 at 2:58 PM, johng said:

Thanks guys..... Will keep you updated.... 

 

It the days before 4 stroke Karting, the 2 strokes were rebuilt after every race meeting, so I assume the wear rate was much greater, especially where high performance is a key factor.

 

The upside is that the 2 strokes were cheap to recon, maybe that is true of your bike? 

It's reasonably cheap... But they can not find the problem... 

Is there any evidence that the carburetor is not original and has been swapped for a "local" one.

It's reasonably cheap... But they can not find the problem... 

17 minutes ago, VocalNeal said:

Is there any evidence that the carburetor is not original and has been swapped for a "local" one.

Original and has factory jets in.... 

On 04/11/2017 at 10:16 AM, Tioga246 said:

Morning guys.... Update on bike.... I cut opened my cdi and no cracks or loose soldier on the board.... Looks pretty clean to me.... I read somewhere, that a guy changed his main jet to bigger I think and his problem went away.... Another thing I wanted to mention, I did the spark strength test and got a shocking experience coz I was not holding that rubber cap on the lead... But when I got to see the spark come out, it looked strong.... Now when I put my new plug B9es that spark did not look strong.... Thai machanic fitted this plug..... And yes every gear is pretty much limiting at 6000 rpm...... 100km max

 

When it gets to 6000 rpm does it 4-stroke? Or does it rev cleanly to 6000. If at 6000 rpm at speed and you pull in the clutch will the engine pick up and rev and sound like a 2-stroke? 

 

Are you sure the exhaust is not restricted? Have you tried taking off the chrome exhaust muffler and running it without?

Our local Yamaha dealer in Khon Kaen has about 50 of these machines in stock, all very old looking and dusty, but with zero km, so new bikes. I don't know why he is keeping them, but this is Thailand.
 
They are two stroke and being fast and bought for that very reason, they tend to get thrashed, so the kms you have may not be that high.

You have the contact details of the shop? I am a sucker for new old stock.

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Hey Neal.... Bike more like a bee trying to sting when at 6000 rpm ting ting ting ting.... 

I did take off muffler awhile ago and since then I've replaced the Cylinder and piston..... Wish I could open this exhaust up and gut it.... I have this picture of a pool of oil lying at the belly of it.... And when I pull clutch in revs drop.... 

17 minutes ago, Tioga246 said:

I did take off muffler awhile ago

Just the chrome tip?

Yes..... And then ended up making a fire and burnt the chrome bit.....Then the entire  exhaust for awhile.... 

If CDI checks out I would remove the stator and test it and the wiring from it.

Can't test - replace

Have you tried a new or different set of reeds?

What's a stator and machanic say reeds are good... Not sure how true that is.... So no have not tried different or new reeds... 

coil?

Got some hope today..... When doing some house hunting, I came across a machanic that was working on a NSR150..... So end of month will take it there.... Want him to gut my exhaust or let me just fit another one on quick.... So ya let's see..... Let him swop parts around and get this beast running to its full potential..... 

Usually the way it happens here. One stumbles onto something by wandering around.

You can buy brand-new NSR exhaust. I saw them for sale last year at a motorcycle accessory shop in Nakhon Phanom. I remember that it was not very expensive.

I bet they have them in shops in your area.

 

BTW, I bought a brand-new NSR150RR back in 1995. It was an amazing little bike. I remember it showed me 170kph (indicated speed).

It would do 160kph two-up. And the brakes and handling were excellent. I remember paying about 75K baht for it.

Hahaha wow.... Yes if it's the exhaust the machanic has a few..... And will gut mine if needed..... I hope that what he meant.... I paid 11 000baht and 3000 to put on a train for me.... And probably another 4000 on it so far.... 

Please let us know the result of the visit to the mechanic.

Will do Neal...... 

On 01/11/2017 at 2:00 PM, Tioga246 said:

Merry Christmas guys.... Finally took my bike to the machanic and we played around with the carb..... First we swopped jets around from other cars he had lying around and yes we got abit closer, but I was not happy, I wanted 13000rpms?.... So we put a NSR150 muffler on that had been gutted and yes there was improvement but was still not happy.... Put another carb on and much better, but still was not happy..... So fiddled with jets and now I have a screaming 2 stroke lol.... Actually scared of it.... I recently snapped my bolt that holds my tank on, so it feels like it will blow off if I go to fast haha.... Not sure what carb we used as he had plenty lying around but do know the slide is more narrow and longer to my standard carb..... I can only think coz I changed my piston and cylinder that was not standard size, pretty sure it was 2 over size.... And thanks guys for all your input.... What a excellent forum this is..... 

 

Well done.

 

Do a plug chop at high speed just to double check it is not running too lean.

 

You can find how to do a plug chop on the interweb.

Thanks.... Now bike been getting worse on running out of petrol so I stripped the carb and it's a PE30 .... I think mine was a 28.... Anyway there was copper wire threaded threw the hole of my main jet 142..... So  I pulled it out not knowing it was there to make the hole smaller... Assembled carb with out copper wire and cleaned my tank tap again.... Was full of shit, but my fuel filter clean... Anyway bike could not run properly at all and new straight away what was the problem.... Found an old TV decoder and used it's power cord for my copper.... Started first time... Have not taken it out on the road yet... And will look up this plug check you were talking about..... Shit I love 2strokes hahaha, 5555555.....

I know it is cool to fix the bike, tinker around and all the that...but do you think it might be time to just get a new 150?

 

150cc 4T ≠ 150cc 2T