Check those valves

Just finished my bike and a friends valve adjustments. Both bikes are back to being trail rippers. Found that .010 for exhaust and .006 for intake seems to be the best setting. Both lashes are on the tight side as per the manual. Friends bike was looseing compression, poping on a rev., rough idle and just didn't have the kick. Found three valves not sealing because of a very tight lash. The factory likes to set them (.004) a little too tight IMO.

By the way...Honda adjusting pads are the same as Yamaha. :cry:

Were these 450's?

How did you verify that the valves were not sealing? Pressure check?

My bike is a 01' 426 and the other is a 00' 400.

The first hint was the fact that I could push the kicker through the entire cycle without useing the de-comp. lever by just useing my right arm. Not good. Then I could hear air hissing back through the carb when getting close to TDC.

On our last ride, the 400 would pop with rev. After the valve adjustment the kicker is rock steady and idles sweet with no pop on rev. My 426 had one tight intake lash and one tight exhaust lash and I now feel more of a kick when I hit the fuel twister. It takes only an hour or so to check the lash, or three beers. :cry:

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