Can adjusting valves too tight cause vibration?

S

Sunspark

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I do believe I adjusted the valve clearances too tight this time. They are still in range I believe just at the very bottom.

What is throwing me off is that the engine is vibrating a lot more now through the seat and handlebars. It sounds ok but the vibrating is different to the point that it is making my hands tingle. It's too much and wasn't there before.

Is this something that can happen if it is too tight? Or is it as someone said, that if it is in range it will feel the same?

It is also possible it could be something else? But if so, what?
 
In general, adjustment of gap on the intakes near the tight side is OK; on the exhaust, gap should be looser.

If the valves were adjusted, then maybe carb/TB sync is now off. That could cause vibration. Have you checked that adjustment?

Not sure which bike you are talking about, but older bikes can have rubber parts deteriorate over time. Vibration can also be caused by air leakage around these deteriorated parts of the engine. Check rubber parts in the intake system -- vacuum hoses, TB bushings, stoppers/plugs -- for cracks and splits. Spray carb cleaner around the area to detect any leakage (the engine idle RPMs will slightly increase and then return to normal if there is leakage).
 
It's only a single cylinder 2012 TU250X with 3200 km so I am not sure what it could be and while it has a throttle body what would it sync to? But one person with the same year bike as me claimed that the TDC mark was in the wrong spot and said that he could prove it by watching the arms move up and a straw inserted in the plug hole. If this happened to me too and I adjusted for 180 degrees off then it would make sense.

The earliest I can get back to this is Wednesday. I think I will observe the position of the cylinder with a straw and the position of the rocker arms and see if somehow my mark is in the wrong place.

This is just me thinking out loud.
 
As I said, I was guessing because I didn't know which bike was in question. You're correct, there is no syncing to be done.

Timing could be the problem too. Don't forget to put your finger over the spark plug hole when rotating the engine. TDC occurs on the compression stroke and you know this when you feel air pushing against your finger. Then use the straw/screwdriver trick.
 
Check the simple stuff first. Front wheel balance and head bearing & air pressure.

Those are common causes of excessive vibrations.
 
Being a single does it have a head steady? If so and it isn't really tight it would cause vibration too.
 
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