900GTS crankshaft balance factor.

hunter · Post by **hunter** » Wed Nov 21, 2007 11:18 am

Hi, My 1980 900gts has Lucas rita ignition fitted, and all the original system has been removed, also the electric start has gone with all its gear. All thats left where the old system was is the small helical drive gear off the crank, the larger starter gear and ignition has gone replaced by a spacer. How do you think this would effect the crankshaft balance factor, as after all it must have been set-up with the added weight taken into consideration.

DesmoDog · Post by **DesmoDog** » Thu Nov 22, 2007 9:30 pm

Maybe I'm not understanding what has been taken off, but from the sound of it, nothing that figures in to the balance factor has been modified.

hunter · Post by **hunter** » Fri Nov 23, 2007 11:20 am

Cheers for the reply DD, its all abit academic really as even if it been a problem I intended to ride the bike first to see if the vibes were too bad or not. With a lifetime of riding old brit bikes, a few vibes I can live with, on the other hand if it was so bad that it made the bike dangerous at speed I would have to attend to. thanks again.

DesmoDog · Post by **DesmoDog** » Sat Nov 24, 2007 6:04 am

I think you're going to find that a 90 degree V twin is a lot smoother than a parallel twin. Vibrations shouldn't be a problem on the Darmah. If the stuff that was removed weighed much all you'll find is it revs faster now. But if you have nothing to compare it too, even that will be moot.

hunter · Post by **hunter** » Mon Nov 26, 2007 1:41 pm

I had a 750gt some years ago, but that was a complete bike with the only variation from standard being a 2into1 exhaust system. This bike has had a lot of work done to it, I think it started life as a 900gts but all the body work has been replaced by NCR gear. My Ducati book says that the 900gts had the crossover gearchange, but I have nothing like I see in the pictures in the book ie, no linkage beside the drive sprocket, just the small lever that operates the neutral switch(that doesnt work either). There is a small section of stainless rear guard(fender) that the 900gts had fitted, but short of running the engine and frame numbers through the DOC to find out I can,t really tell what model it was. any ideas.