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Yamaha Exhaust Valve Control Unit Repair - YPVS

A busy day at the lab, repairing four ypvs controllers for Damian(UK) and modifying a RD500 YPVS unit for Daniel(USA). Thank you all for trusting my services. 

The Mail is so slow now...

There are issues with posting delays lately as a result of both limited air transportation and changes in how postal operators deliver. That said, I always do my best to have any orders delivered back as soon as possible.  Here are a few units that I received, repaired - modified and delivered back within 48 hours. A Honda Rs250 NX5 PGMII for Oliver(GB), a Tzr125 YPVS controller for Simon(GB) and a Rd500 YPVS unit for Tony(USA).  Thank you all for your understanding. Nick

Nsr250 PGM3 Repair - Upgrade

Most PGM units now have almost 30 years of use and ignition fail is a thing to expect. Aged parts and drained capacitors have a lot of side effect as well. A PGM unit with low miles puts out about 300V DC to the ignition coils but most of them rarely exceed 280V DC.  All PGM3 units leaving the workshop put out 320V DC and the cleanest possible waveforms as they were intended when they left the factory. On a well serviced unit you will immediately notice easier cold starting and a crispier sound and you haven't even ridden the bike yet! Ps. Fourteen PGM units with ignition issues, all repaired and I now have to proceed to Rc Valve checking and repairing, a couple solenoid issues etc. but that's the easy stuff. Thank you. Nick 

This blog is now 10 years old.

Time goes by like a two stroke motorcycle and this blog is now ten years old.  The first post on this blog was made on the 6th of July 2010. Have fun and keep the two strokes alive. 

YPVS Modification - Bonus Exhaust Curve for RZ350

The below ypvs exhaust curve was stock on John's(USA) '86 Rz350 bike. I'm not sure I've seen this curve in the past. The exhaust valves starts opening at 7.000rpm and are fully opened at 9.500rpm. A few photos of John's RZ bike. 

Honda Rs250 A-KIT PGM unit

Here's another one ultra rare PGM unit that belongs to Pomper(NL). This one is a reprogrammable PGM unit for the late Rs250 bike. Yes, you see correct, it's a PGM3 and not a PGM2. Even though the internal is quite similar to the usual PGMIII unit, the pinout is totally different.

YPVS Controller Modification - An extra exhaust curve for TZ250L.

I've been working on some YPVS controllers for Pete(GB), Gavin(GB) and LES(CA) and I just found out a new exhaust valve curve that I want to share. Pete owns a Tz250H converted to an L (electronic power valve). I have a few TZ250 (mostly reverse twins) exhaust valve curves on the blog but the below one is new to me.

Paul's Nsr250 Mc21

Many thanks to Paul(USA) for the photos of his Nsr250 and his kind words about the Battery Eliminator. I purchased your battery eliminator for my NSR250 and it works great. Bike starts easily every time. Thanks, Paul

This blog is now 9 years old.

Time goes by like a two stroke motorcycle and this blog is now nine years old.


Many thanks to Terry(UK) for using my sticker on his magnificent RZV500R bike.