valve ajustment

[250rforlife]

ok well im tired of paying someone to ajust my valves. now i have a owners manual and its easy to do. but do i have to shim the valves? and on other quads the all 450rs when do i have to shim the valves. and is it hard to shim valves????

[CJM]

No shimming needed. Its a super simple task imho to do.

Remove inspection covers on left side crankcase (6mm and 10mm hex key needed), remove valve cover caps with 24mm socket or wrench. Take ratchet with extension and 17mm wrench, turn counter clockwise till the "T" mark lines up with the notch in the upper cover hole and adjust away.

Best advice I can give you is to be sure the rockers have some play in them-sometimes this can be tough to get accomplished-dont adjust till they have play otherwise they will be adjusted wrong.

This is a write up that will prove helpful http://www.atvriders.com/articles/valveadjustment400ex.html

[NMills]

If they are over adjusted... will it tap??

[CJM]

Originally posted by NMills
If they are over adjusted... will it tap??

Depends on how you define tap. All of then tick or tap to a degree and every engines different, but yes if the valves arent adjusted right it will tap. More they are out of spec the more it would tap.

[NMills]

I know they all tick/tap... but since putting it back together is seems a bit louder then before... runs good... goes good... hate to get it on the trails and blow it up tho... that makes for a crappy day...

[SPE_Motorsports]

If you over adjust them they will be perfect!! haha. Having the valves too loose will cause the rockers to tap and the cam wont open the valves as designed... and vise versa if too tight. And one thing to pay attention to with your valves, check the tolerance of valve lash before you adjust them and compare both intake valves together, and then exhaust valves together. Keep these numbers handy. If one valve seems to be getting more and more worse each time (with normal wear in mind) there maybe something failing in your valve train...

[dariusld]

With valve adjustments, its better to be too loose(run crappy) than too tight(burn a valve). But perfect is best:)