how do i rebuild my yz125. i have a cracked piston and a scored cylinder?
is there a how to anywhere online?
what else should i do performance wise? i already have fmf factory pipe and q silencer and a air filter.
2007-11-27 12:16:03 · 2 answers · asked by Anonymous in Cars & Transportation ➔ Motorcycles
http://www.dansmc.com/MC_repaircourse.htm
Will give you an idea of what's involved.
DO NOT even touch a wrench to your bike without a shop manual in front of you.
http://www.motocom.com/motorcycles/
If you ask nicely, maybe Santa will bring you one.
2007-11-27 13:41:26 · answer #1 · answered by guardrailjim 7 · 1⤊ 0⤋
You don't mention what year YZ you've got, but the newer ones all have a nikasil bore. These require specialty plating services that are only offered at a few companies nationally.
US Chrome and Millennium are the two I've used and had good luck with.
You can purchase headgasket and basegasket, piston, rings, pin, clips and small end bearing from Yamaha, or buy a kit from Wiseco that includes these parts.
You'll send the cylinder and piston to the plating company, they'll refurb the cylinder, and match the bore to the new piston.
Once you get it back, you'll carefully clean and install the new parts according to the shop manual that santa brought you!
Also, broken pistons are caused by excess clearance - from a worn piston that went too long between replacements. Make sure you follow the replacement schedule shown in that shop manual to avoid having the same problem again.
2007-11-27 17:06:55 · answer #2 · answered by ducatisti 5 · 1⤊ 0⤋