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View Full Version : valve adjustment (am i right)



rob0781
05-19-2005, 02:19 AM
Ok i'm getting ready to adjust the valves on my yamaha 200 and i can't find my manual...i know the specs but am just unsure of a few things,can i adjust the intake valve correctly with the engine in the bike?seems kinda tight,Also where is the timing window located on this engine?Do i align the "T" or the "F" to adjust the valves?And last question how exactly do i do this put the feeler between the rocker and the valve and tighten the nut????

rob0781
05-19-2005, 04:51 AM
can anyone tell me if i'm right here,i was searching and i read that pretty much anyone can do it...just wanna make sure i'm doing it right,From what i found--- flywheel on the "T" on the compression stroke(rockers on exhaust and intake should have slack)loosen lock nut and loosen screw ,place the feeler in between and tighten screw till theres some drag on the feeler,then tighten lock nut and recheck the clearance....This sound right????Also the only thing thats got me stumped is i put the feeler between the rocker and the what?????Valve i'm guessing??

rob0781
05-19-2005, 05:32 AM
on the yamaha after you loosen the locknut is it a screw or a bolt you turn ???cause i had my valve cover off and that doesn't look like a screw...might be lighting was poor when i looked,if it is a screw ir's small and looks like it's not easy to get....

jenndnn3
05-19-2005, 08:28 AM
Yes feeler between the rockers and valves, and yes the adjustment nut is very tiny.

Wickedfinger
05-19-2005, 11:01 AM
The first thing I do when adjusting my valves is adjust the cam chain first before you do anything. Its been a long while since I did that on a Yamaha 200/225 - but - I believe its an auto adjuster like the Hondas and you just loosen the nut on the cylinder side tower while its running and it'll adjust itself (someone correct me if I'm wrong). Take out the sparkplug to ease up the compression. I usually remove the pull starter to get to the nut behind it and use a socket wrench to hold the crank still while I line up the T to the line on the case or the groove in the threads (I cant remember how yamaha does it) After taking off the valve adjuster covers, the rockers need to be "loose" when you touch them - that way you know the piston is on the compression stroke then you line up the "T". Insert the feeler gauge on the exhaust side first - you will be able to tell right away if it needs adjustment. *Note - if it has a bit of resistence going in - not almost impossible to get in or very little at all, just snug - you don't need to adjust the valve and leave it be. If its off (probably no resistence wide) keep the feeler in there, loosen the larger lock nut, then use a small flat-head to tighten the adjuster down onto the feeler gauge until resistence is fealt. Do not over tighten it - the gauge should be able to move with a little effort freely but with resistence. Keep the gauge in there and while holding the adjuster perfectly still ( a second set of hands and eyes is helpful) tighten the lock nut back down (not sure of the torque). Pull out the gauge, rotate the crank/piston through one or two complete cycles and check the clearence again. If its ok, adjust the intake the same way. Button it up, pat yourself on the back, let it warm up to operating and take it for a quick ride.

edog
05-19-2005, 11:19 AM
What are the sytums for doing this tune up?

rob0781
05-19-2005, 02:18 PM
What are the sytums for doing this tune up?
ticking valves....and i have to fix my carb so i figure while i got the tank and all removed might as well do it all..

rob0781
05-19-2005, 10:51 PM
well i got my carb all back together and working great just the idle is off no matter how mych i play it's doesn't really wanna idle well,i was told to replace the needle and seat i can see it's worn would this help???also i haven't got the valves adjusted yet cause princess auto was sold out of feeler guages....

rob0781
05-23-2005, 11:17 PM
Well i finally did the valve adjustment and it turned out great,also cured my ticking and the throttle response improved and it feels like it's got more power...Well worth the 30mins it took,anyone who has a ticking machine or hadn't checked the valves at all or in a long while i'd recomend it..


Forgot to add bike starts with half a pull and idles great now too...

MTS
05-23-2005, 11:22 PM
just a question hear- i know for car motors ect normally we warm the motor up befor adjusting the valves so all the metal has expanded and you get the correct setting on the valves as if you do it cold you could put them too tight and possibly do dammage......same with ATV's or no?

rob0781
05-23-2005, 11:24 PM
well i was told to adjust them cold,makes sense ...cause if you rebuild a whole engine the valves will have to be adjusted before it's started..

freewheel3
05-23-2005, 11:28 PM
just a question hear- i know for car motors ect normally we warm the motor up befor adjusting the valves so all the metal has expanded and you get the correct setting on the valves as if you do it cold you could put them too tight and possibly do dammage......same with ATV's or no?
Not sure about all ATVs but my Yamaha Service Manual says to do it cold.

MTS
05-23-2005, 11:31 PM
well i was told to adjust them cold,makes sense ...cause if you rebuild a whole engine the valves will have to be adjusted before it's started..
yea but first thing you do after wards is re-adjust them...least i do, i know for small engins (B&S) we leave a thousandths for heat expansion....

rob0781
05-24-2005, 03:41 PM
i'm gonna re-check them in about a week i also wanna put a dab of lock tight on the lock nuts..