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TRX 400 2004 won't run after valve clearances?

1712 Views 10 Replies 7 Participants Last post by  Hondawasaki
A friend has a TRX 400ex, he checked the valve clearances (as far as I know) tightened them a little as they were loose.

Since the above the bike hasn't started, I've had a quick look at the manual and set clearances to 0.1 and 0.12 and it still won't run, it seems such an easy straight forward job I can't understand what has gone wrong? Am I missing something? It's the first time I have ever touched an ATV, I have worked on dirt bikes a lot. I am reading about a decompressor adjustment?
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It was running before the valve adjustment, I assume? You sure you had the timing marks set to TDC on the compression stroke and not exhaust.
The bike ran great before he checked the clearances. I'm not sure about him but I personally turned crank anti-clockwise with 17mm socket until I saw the T mark and lined it up and felt free play in the rockers which is where it's meant to be? I then set it to the proper clearances.

The exhaust valves should have .005 inches of clearance, and the intake valves should have .004 inches of clearance.
I am using mm as I am in the UK sorry
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Sounds right. Start from square one, maybe? Got spark and fuel flow?
I know the stator is good as I have connected another plug to the lead and it sparks fine, unfortunately I haven't got a tool that will fit the plug currently but the chances of the plug going bad are very slim surely? It worked fine before he did the clearances!

One thing I have been wrong on is the year, it's actually a 2005 model. I am reading through the manual at the moment and clearances seem the same. I still can't find a good explanation on the decompression clearance!
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