Wow, R Moore, your info is so good that I copied and saved it.
I have an NS150E, it says NSR on the tank but NS150E in the green book.
You say that TYGA exhaust is the way to go. I am not a racer, just a thrill seeker. (why did I sell my CRM250? - I did win a few drag races - Because I was hoping to find a CRM500)
Now I am stuck with an NSR150 without a power valve.
Thai mechanics never heard of TYGA expansion chambers even though they are manufactured in Thailand. They recommend DBS after-market drag exhausts, apparently the choice of drag racers on all bikes and costs around 1000THB.
Mine is rebored to 175.cc
I am surprised that you recommend an NSR 250 carburettor. I have heard this before. You mentioned Keihlin carb and NSR 250 M21 carb.... are they one and the same? I would think that the size of the NSR250 carburettor would not match that of an NSR 150 - or in my case 175cc.
I have an aftermarket carb of unknown (to me) brand. It is ( according to the local mechanic) bigger. How does a 250 carb fit on a 150 bike? air fuel mixture is all I know about carbs. very difficult to learn about bikes in Thailand because of the language barrier while talking with Thai mechanics.
I want a rocket.
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Thailand NSR150 owner, NSR250 wannabe owner after I learn the basics of my cheap-assed bike.