Questions & Answers for: compression for yz 125

...it can you help check your compression I had a 94 yz that done that when i checked the compression it was really low so I put new rings on the piston and that's all it took to bring her back to ...

whilst doing h speeds over 15 minute period my yz 125 90model just shut down and when tried kickin it again it felt like no compression and didnt start sounds like an isue with your powerport

...yz 125 and it keeps fouling plugs and bogging out could it be the top end? A compression test will tell you your condition. (Throttle wide open while doing that) If that's good, your jetting is too ...

yz 125 It is normal for the powervalves to leak, but it does depend on where it is leaking from. The hose on the left side is the power valve chamber vent - it is normal for it to leak thick black oil

my 125 yz has lost compression in the motor and will not kick over it has spark if its a good spark it should start.try bump starting it,if no joy then possibly piston rings or other simalar.

...yz 125 2001. hi i have rebuilt the the top end on the bike and all seems to be fine with compression etc. Now attempting to make the first start the bike wont fire. there is fuel coming out of the ...

...yz 125. Melted a hole in the piston but didnt score cylinder. Replaced top end. Wont start. Has good fire. Crank case oil was a little grey. New plug,fluids,fuel. I would be checking compression it ...

...a new piston into my 94 yamaha yz 125 dirt bike. When i try to start it has very low compression. I had a similar problem check to make sure the rings line up right and if that dosent work let me ...

...yz 125 and its fouling plugs pretty quick and it has low compression bout 100 - 105 psi should i do the top end and powervalvues cause it stillstartsfirst kick and runs like a champ If the plugs are ...

...compression and spark but wont start before when it was running it back fired every once in a while and then just died Hi, Anonymous are you getting fuel? for this scenario you will need your ...