Over size valve guides?

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Paul Croft
Cucciolo - the Lil Pup
Posts: 14
Joined: Thu Dec 15, 2016 2:25 pm

Over size valve guides?

Post by Paul Croft » Sat Dec 31, 2016 3:13 am

Hi all, sorry if repeated, but cant find answers. A few questions.
Is it necessary to order oversize guides, even if present ones are a tight fit?
Should there be any end float on rockers?
And lastly for now, there was a metal ring/shoulder on each of the fork stations below the bottom yokes, that I had to heat to remove. Are these necessary, they wasn't even of equal fitment (one lower than other) 1980 Darmah.
Many thanks, Paul.

wdietz186
888
Posts: 672
Joined: Sun Sep 10, 2006 4:40 pm

Re: Over size valve guides?

Post by wdietz186 » Sat Dec 31, 2016 8:05 am

You will need an interfence fit of approx. .002" between the cyl. head and guide with the head heated to about 250F and the guide at room temp. The hole needs to be clean and straight. A good fit is essential because there isn't a lot of meat where the guide fits and they can come loose and cause problems. There should be minimal side play on the rockers and the rocker needs to be centered on the valve stem, that is why all those thousands of tiny shims are in there slipping out of place when you try to install the spindle. Can't remember seeing any rings on the fork tubes above or below the triples.

Paul Croft
Cucciolo - the Lil Pup
Posts: 14
Joined: Thu Dec 15, 2016 2:25 pm

Re: Over size valve guides?

Post by Paul Croft » Sun Jan 01, 2017 2:39 am

Thanks wdietz, that is very useful info. Happy new year.

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