Recent content by athomas

It's on the list of things to check!

That was my logic and why the service manual confused me, I'm going to put it down as a translation issue and assume when they say exceed the limit they actually mean smaller than the limit. Pulled the rest of the valves and the keepers look fine, hard to tell if the damage to the failed...

Actually it very specifically says 'Free Length' (I've included the section) which is what has me confused! Stripped everything down today and it looks like there is no other damage except a slightly bent valve and a couple of minor marks on the piston, so my current theory is a weak spring...

I'm currently undergoing a tear down of my GN250 to figure out why a pair of valve collets removed themselves (Engine shutdown while out riding due to no compression, it seems one of the ex valves removed its own collets but luckily didn't drop and destroy the piston!). As part of trying to...