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Nsr250 PGM Spacers

Lazy afternoon at the workshop, turning some spacers for a NH3 PGM unit.

Recent posts

Yamaha SDR200

I had recently repaired - modified a YPVS control unit and also made a custom SDR200 leak down tester tool for Matthew(UK). The Sdr200 is a unique bike with a Trellis frame. The YPVS exhaust valve curve is also unique to this model. 

And here are the YPVS settings, specific to the SDR200 model.

This blog is now 8 years old.

Time goes by like a two stroke motorcycle and this blog is now eight years old. 
P.s I suppose I should have posted this on the 6th of July but better late than never.

Leak Down Testing on a Lambretta

Mark(UK) performing a leak down test on a Lambretta TS1 238 cc engine with his custom tool. Many thanks Mark and I hope everything goes well with your project.

Yamaha DT200R 37F '86, YPVS Curve

I just repaired a YPVS unit for a Yamaha DT200R 37F bike, that belongs to Tony(UK) and I have another one rare YPVS curve to share. This unit doesn't seem to use the regular DT200 ypvs curve but instead uses the one below.

P.s Dt125 and Dt200 owners might want to give it a try.

Nsr250 PGM Key Ring

A low budget birthday gift for a friend...

CR125 HPP, Altering the Exhaust Valve Timing

A recent modification on a '98-'99 Cr125 bike that alters the exhaust valve timing. A simple spacer made on the metal lathe that adds some preload on the governor spring hence retarding the engagement with the exhaust valve linkage. This mod can help for enduro use or with bigger carbs.
I mostly followed the instructions from the below link though I made the spacer slightly thinner at 2mm thick.
Link at :
Honda 125 - HPP setup TIPS & TRICKS & TUNING @