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Montesa Valve Clearances

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Hi

I am after some advice. My Mont was running well but the top end was a bit noisy so i thought i'd do the valve clearances.

As per the manual I got the engine to TDC on the compression stroke. I removed the plug and put my finger over the hole to feel for compression.

As the clearances are tight and its awkward to get the feeler gauge in its hard to actually check what the clearance is. To get the feeler gauge in i had to loosen the adjuster to get a bit of clearance, insert the gauge and tighten it back up. I appear to have correctly set the clearances.

After doing the valve clearances, when operating the kick start it gets to a point where it becomes hard to move. If you keep the pressure on it will slowly complete the travel through the kick start's stroke. This does not feel right. I have only operated the kick start gently.

I think the exhaust valves are not opening and the compressed air is blowing past the rings. I did take the flywheel cover screw out that tells you what position the flywheel is at to see if there was any particular point where the kick start is getting this resistance. When the kick start passed through the "resistance" oil blew out of the hole.

I have obviously done something wrong but I don't know what. Any suggestions?

Thanks Scragg

It was not tdc on the compression stroke, I've had the same problem before. Find tdc using a wire inserted into the spark plug hole, looking for the rocker arms moving and looking for the marks the flywheel. Its not as simple as it makes out in the manual.

+1 on the wrong stroke.

You know you on the right one (compression) when both rockers move in the "clearance". Especially as the Honda clearances are wider than most 4 strokes.

If you line up the flywheel mark for top dead centre and move the rockers and both inlet AND exhaust are NOT free to feel clearance go again until you feel clearance in both rockers.

Then check clearances. I use feeler tapes bent at just the right angle to insert. Can take a bit of mucking around but you should not have to loosen adjuster to insert feelers. Well... unless all clearances are zero and doubt that would be the case if its running well when warmed up, and normal to kick start.

Mags

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