175 TS Narrowcase Crankshaft Shimming Advice

[double diamond]

0.01mm is 1/100th of a millimeter. a .004" shim is ~1/10th of a millimeter. The Ducati NC service manual specifies 0.03mm to 0.05 mm for crankshaft end play. If you only have 0.01mm end play, this is a bit tight according to factory specs, the debate about end play notwithstanding. Matt

[Jordan]

That's right, my error sorry.

0.01mm is 1/100th of a millimeter. a .004" shim is ~1/10th of a millimeter.Matt

[Samurai]

Hans/Matt,

Good information from both of you, many thanks. To be honest, I was a little hesitant about having absolute zero freeplay that I've read about and even 0.01mm was a bit uncomfortable, given my past experience with my ST4 (mentioned at the beginning of the thread).

Having said that, I regularly shim the closing shims on beltdrive Desmoduos to 0.01mm after ensuring that there is no binding. However, I think I'd be more comfortable with the crank having just a little more play, say at the lower and of the Ducati spec.

I've got a full crank shim set from Classic Ducati, so I think I'll experiment a bit further to see how close to 0.03mm I can get.

Incidentally, those are the same specs as the closer shims on belt drive Dukes, some things never change it seems

[Samurai]

Ok, thought I'd share this information with you all out of interest.

I called Brian Silver at Moto Marianna last night, who had rebuilt the crank for me (he's a well known Bevel Guru here in the UK).

His advice was the same as Jordan and Hans, in that if I was as close to zero as possible and the crank still down freely, then I was about right.

He warned that if I had much more, than when the engine for warm, the clearance would increase due to the expansion of the alloy engine cases. The result would be too much clearance which is bad news off the crank bearings and the bevel gears.

So in light of all the advice I've received from you guys, I'm happy to leave the crank with the 0.01mm play that I have now, which is bugger all really.

All the help has been really appreciated and no doubt I'll be back for more when I get around to shimming the actual bevel gears