'03 YZ85 chain slack

[crfdirtpilot]

Bought a used 2003 YZ, owner didn't have manual. Just need stock spark plug # and chain slack measurement(no sticker on bike). Its sunday and no shops are open. Going to set at around an inch unless someone can help. Son has gotta ride today. Thanks in advance

 

[Vic]

Midpoint between sprockets, two inches will put you in the ballpark. One inch will be too tight.

Plug is most likely a BR9E*.

 

[crfdirtpilot]

chain

Thanks, multiple add-ons(pipe/ jetting) plug is still stock. 2" seems loose my CRF is 1 1/8. But too loose is better than too tight.

 

[Chili]

Most of the guys I know use the 3 fingers rule. 3 fingers of slack at the end of the chain slider on the swingarm. Not real scientific but usually in the ballpark.

 

[Vic]

Most of the guys I know use the 3 fingers rule. 3 fingers of slack at the end of the chain slider on the swingarm.

Same, here.

I just measured my three fingers and they measured 2 1/4 inches. And, I have small fingers.

:)