- Joined
- Jan 22, 2008
- Messages
- 954
For those not familiar with Ducati singles, the flywheel they used had a quite heavy brass rotor riveted to a steel hub, mounted on the crank with a taper but with no Woodruff key. The flywheel sits inboard of the primary pinion and the drive side mainshaft is supported by an outrigger bearing in the primary drive casing. I cobbled together some old bits to show the arrangement, from left: the side casing with bearing, the journal on which the bearing runs, pinion, flywheel, drive side main bearing and crank. Oil is fed from the oil pump through the end of the timing side mainshaft, through a centrifugal sludge trap in the timing side crank web, through the crankpin to lubricate the big end bearing and surplus oil is then fed into the drive side mainshaft and out through a radial hole in the primary drive pinion to lubricate the primary gears. The pinion is a light press fit on the mainshaft and is secured by a Woodruff key. I think the Commando's is a better arrangement, since the primary sprocket is keyed and is on a taper.
When the bike last ran, the flywheel came loose at a trackday and ruined the taper. Crankshafts are very hard to get for these bikes, so I had mine repaired, at considerable cost. I am now using an Electrex flywheel and alternator, 12 volt, 120 watt. This replaces the original 6 volt, 80 watt system, which was weak but which I never had any electrical problems with. http://www.electrexworld.co.uk/stk-163- ... 381-0.html
I raced the bike without a flywheel and had no problems, and it was nippier out of corners. Some people fit smaller, lighter flywheels for racing. I would want a flywheel for the road, though.
The original primary gears are helical, mainly to keep the noise down. A popular mod for racing was to change these for straight cut gears. This was supposed to be more efficient at transmitting power but is also supposed to be noisier. To be honest, I didn't notice the difference. A dry clutch would have been nice but the conversion was always, in my opinion, more expensive than it was worth.
When the bike last ran, the flywheel came loose at a trackday and ruined the taper. Crankshafts are very hard to get for these bikes, so I had mine repaired, at considerable cost. I am now using an Electrex flywheel and alternator, 12 volt, 120 watt. This replaces the original 6 volt, 80 watt system, which was weak but which I never had any electrical problems with. http://www.electrexworld.co.uk/stk-163- ... 381-0.html
I raced the bike without a flywheel and had no problems, and it was nippier out of corners. Some people fit smaller, lighter flywheels for racing. I would want a flywheel for the road, though.
The original primary gears are helical, mainly to keep the noise down. A popular mod for racing was to change these for straight cut gears. This was supposed to be more efficient at transmitting power but is also supposed to be noisier. To be honest, I didn't notice the difference. A dry clutch would have been nice but the conversion was always, in my opinion, more expensive than it was worth.