Valve Shims

[slob]

Originally Posted by Murray Mint

But where are you guys getting your shims from what with all this bloody COVID-19 and the likes and bike shops being shut?

I think Moto Rapido parts dept is still operating mail order

is there a way of uploading a file to the forum?

PM sent

[slob]

http://www.ukmonster.co.uk/downloads/DesmoCalc_v2.xls

[Terryphukwit]

I have got my vertical head off at the mo so checking the clearances, all but one are close but one exhaust closer is 40 thou, serious amount of movement, I now need to pull the rockers and cams but I can't see anything wrong so far it must have been badly calculated and not checked or is there another possible reason for this.. Thanks. .

[slob]

collets not properly seated or replaced upside down?
is the valve stem stable in the guide?
is the valve sitting right in the seat (stem straight and seat cut/lapped properly)?

[Terryphukwit]

The love seat is good, I thinking the collet may be the issue, iv got the open rockers and cams out just on the closers now, trickier with the springs...

[slob]

I generally use a small aluminium drift and a toffee hammer and tap the valve stem to ensure everything’s fully seated after refitting the collets. Look for the polished edges to ensure the collets are the same way up as the where before removal. I also always turn the engine 720deg by hand and recheck everything when i’m done.

[Terryphukwit]

Thanks, I'll follow that and make sure there well seated, that's if I ever get it back together, I have some pitted rockers to deal with now, vertical cylinder, intake right hand opener, exhaust left hand both, I am going to post an ad on here as I really can't do new prices at this time, have already spent quite heavy. Any help on cross compatability with models would be appreciated, I believe st4, s4r are the same but there are likely others??

[Dukedesmo]

Originally Posted by Terryphukwit

Any help on cross compatability with models would be appreciated, I believe st4, s4r are the same but there are likely others??

Basically all 'Desmoquattro' use the same rockers; 748, 851, 888, 916, 996, ST4, S4, S4R but not the 'Testastretta' 998cc versions onwards such as S4RS, 998, 999, 749 etc.

As it happens, I have some spare rockers if you're interested.

[Terryphukwit]

Originally Posted by Dukedesmo

Basically all 'Desmoquattro' use the same rockers; 748, 851, 888, 916, 996, ST4, S4, S4R but not the 'Testastretta' 998cc versions onwards such as S4RS, 998, 999, 749 etc.

As it happens, I have some spare rockers if you're interested.

Thanks, and that would be awesome, I need 2 x left hand openers and 1 x left hand closer..would you like to pm m with the price..