outtacontrolla wroteLater on testastretta reace bikes deleted the springs completely for max power , but harder to start and tick over , shorter intervals for strip and rebuild etc .
The corsa springs are pretty light anyway , but increase emissions on road bikes .
Hope this helps , Steve .
I agree Steve- the Corse springs are very light and that is why I normally would pull the heads so that I could use a dial gauge on the valve face to assure that I set the closer gap correct.
I am currently restoring a friend's Carl Fogarty's '93 888 WSB (his #2 bike) and I did not want to pull the heads so I pulled the frame and set the openers with the barely feel any drag method, and the closers using the stuff-in-feeler gages and rotate cam method. I double-checked the closers using my dial gauge setup that I use to set cam timing and found the stuff-in-feeler gages can get you about .001 too tight. But now that we no longer set the closers at .001-.003 like we did racing in the late ''90s, this is purely academic.
I have found that the street 851's also used the light Corse valve springs-- at least until '92--but for sure when the factory was still using the thinner half rings and the weird closers.
So if someone has just bought an '89-'90 851 be sure not to set your openers as though they have the stronger later springs. If you feel anything more than a very light drag on your feeler gauge you are into the openers and your calculations for the closers will be off--as well as setting your openers too lose.
