Normally I wouldn't need help with procedures such as adjusting the valves on my engine, but I've had a Honda service manual on order for my new '00 400EX for over a month now, and the dealer has no idea of when it might come in. At any rate, it's time for the initial 20-hour valve check and I have a big ride planned for this weekend, and would really like to adjust them before riding it any more. If possible, could someone please scan in the pages from a Honda service manual and email them to me? I'd greatly appreciate it! TIA!

 

no service manual needed. the only confusing part is finding top dead center. there are 3 marks on the fly wheel you want the one with the t behind it. it's a vertical line with a horizonal t. that's it. tolerences are .004 for the intake and .005 for the exhaust. the valve caps are 15/16 in bolts heads. thats all there is to it.

 

I performed the same task myself too and the only pain in the neck was the plastic and plastic rivets. Everything else is straight forward. By the way I had no trouble getting the factory service manual.

 

Okay then, sounds easy enough. Just wanted to make sure I could find TDC, and it sounds as though the marks are easy enough to figure out. I also know enough to check the rockers and make sure there's some play...if not turn the motor over and re-align the marks. BTW, if anyone knows the torque spec's for the valve caps, please post them.

Anyhow, don't know what the problem is with getting the service manual, but apparently the publisher only prints them when they get enough orders. The dealer checked and said it was printed and being shipped, but that was two weeks ago. Must be coming via Pony Express...

 

Knowing the significance of the marks makes finding TDC easy; you're hep on the ambiguous two TDC's, one between the exhaust & intake strokes, and one between the compression & power strokes (that's the one you want!).

On all four-stroke engines, at TDC on the compression stroke, both intake and exhaust valve are FULLY CLOSED.

If you cannot find any index marks on an engine, remove the spark plug and turn the engine with a wrench or auxiliary starter cord; feel the spark plug hole with your finger; rushing air indicates the start of the compression stroke. Stick a piece of wire, pencil, whatever, down the spark plug hole--feel the piston rise to its zenith; when the piston stops and begins to retreat, that's TDC where you want to adjust your valves.

Chances are, you only need to measure your 400ex's valve lash; you probably don't need to adjust them; however, checking them is a good idea, just in case. (In my opinion, valve cap torque is not critical (I think they're sealed with O-rings); just get 'em tight without stripping 'em.) Good luck!

Tree Farmer