As the thread title suggests... I Tore my topend on the ole 400 apart a little bit ago - cylinder was fine and the guy who's buying it from me said he wanted to keep the stock bore, so clyinder was basically left alone. I did a super light hone to get back the cross-hatch pattern, measuring along the way, and threw in a wiseco piston. Again, the guy who was buying wanted to keep as many stock parts in as possible, so I'm leaving the stock cam in. Replaced all 4 valves, and ground/lapped seats to a good seal. But before I had torn her apart, the motor had always ticked like crazy. Checked the valve clearance over and over again, and that was always fine. Took her into Honda to have them adjust them, got it back and she did the same thing. That was all pre-disassmbly. Right now, I'm sitting with the clyinder/head on, but valve cover and cam assembly are still off. The only thing I can think now is decompressor assembly? Is there any way to tell if it's malfunctioning while the cam is not installed? The decompressor spins freely around the shaft, and will not turn the opposite direction (what's suppose to happen I believe?). Is there any other way to tell if it's malfunctioning, or have any other recommendations on what to try to get her to stop?

Help would be appreciated

 

My friends 416EX does the same thing. We replaced the timing chain and the chain slide on the tensioner side and it helped some. What helped even more was going .001 tighter on the intake and exhaust.

Hope this helps..

 

hmm...definitely good to hear some suggestions. Thanks for the tips [img]i/expressions/face-icon-small-smile.gif[/img], anymore opinions from around the house would be appreciated. Sounds like I'm going to have to bust out the already empty pocketbook again [img]i/expressions/face-icon-small-confused.gif[/img]

 

My 400ex has done that since the day I bought it new in febraury of 99. Rebuilt it a few years ago, replaced basically the whole top end and it still does it. I have had several mechanics go thru the engine looking for problems and they all say that its normal for the xr400 and 400ex. Most say that it has something to do with the RFVC. Which makes sense considering just about every xr400/400ex I have ever heard had valves that tick.

You seem to know your stuff and I am sorry that I don't really have a solution, just make sure you torque everything to specs and leave it at that. No need to spend money you don't have on a problem that wont go away.

If someone does know of how to get rid of the annoying tick please share as I would LOVE to get rid of it too.