350 Sebring

[JJJ12345]

I am new to Ducati singles.I picked up a 350 Sebring. The motor was rebuilt a few years back by a reputable shop and never put back in the frame. I brought it home, put a battery in it, and a few other things, got good spark and tried to start it. I can barely get this beast to kick through. With the plug out, it kicks through quite nice. I thought it may have a high compression piston installed, so I removed the top end and the piston appears to be standard. My 250 is easy to kick over compared to this 350. Any thoughts appreciated. Thanks.

[JJJ12345]

Another pic with the cylinder on.

[Jordan]

Could be your technique, while OK for the 250, needs to be more deliberate on the bigger engines?

This works for me (350 Desmo, no compression release):
Place on centre stand, stand beside left side of bike.
With right foot, push on kick lever with gentle pressure, until it's felt that Top Dead Centre on a compression stroke is reached and gone over (just).
Release kick lever.
Confirm fuel ON, flood float bowl or use choke as required.
With the throttle held slightly open, give the lever a serious kick with right foot.

A wide open throttle would allow too much air into the cylinder, which will become difficult to compress, preventing it from going over TDC on compression stroke.
The primary ratio on 350/450 is different from the 250 - should be easier, but less revs to the crankshaft per kick.

[Nick]

Or, put the bike in gear, roll it backwards until the piston comes up on compression, then put the bike in neutral and kick.

Whatever you do, don't just tromp on the kick starter and hope for the best. Aside from possibly injuring yourself, you may ruin the kickstart mechanism.
The Sebring came with a compression release as standard equipment for good reason. Ideally one uses that to position the piston just after TDC on compression before kicking.

Too, the bike is so light that it is easy to push-start (after properly locating the piston of course).

Properly set up the Sebring starts in one or two kicks every time (or one push!).

Edit: I should mention that I always kick it through once with the choke/enrichener ON and the ignition OFF to prime it first.

[JJJ12345]

Some good tips/advice. Thank you. I don't think there is room on this early model for a compression release. Will the cable mechanism work with the small Monza tank?

[Nick]

It should have the compression release in the exhaust valve cover, and the handlebar lever for it should be integral with the clutch lever perch.

However, mine is a square tank Sebring. Perhaps the round tank models didn't come with one...? A look at period brochure, the manual or a chat with other Sebring owners should clear the matter up. Regardless of whether it came with the release as standard or not, I would find one and install it. Repairing a broken kickstart mechanism is much, much more trouble than installing and using the release.

Perhaps Ducati fitted it to the later square-tank models after riders broke too many kickstart mechanisms. No doubt others here can offer definitive answers to these questions.

[Jordan]

None of the street model (as opposed to off road) desmo models used a compression release - even the 450.
I used the same technique when I owned a 450D, and it's not difficult once mastered, as described earlier.
There's incentive to keep it well tuned though!
Having said that, a friend with a Norton Commando (non electric start model) could not start my 450D, even after many attempts.

[Nick]

However, the later wide-case models also had a stronger kick-start mechanism. It's the relative weakness of the N/C kickstart mechanism that make me so careful about starting. Too, one never knows what sort of treatment it has suffered from previous owners....

[Jordan]

Good point - I see that's why you prefer to bump start rather than use the kicker.
Nevertheless, just pushing on the lever, even without a compression release will get the piston where it's needed before a start attempt too.

[Ventodue]

None of the street model (as opposed to off road) desmo models used a compression release - even the 450.

True, but the Sebring is a hair-spring bike, so would well benefit from having one. Both the 350 and 450 SCRs had 'em.