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Hi All,
I hate to make my first post here a "plea for help" but in reality I REALLY need advice. I bought this '82/'83 Morini 3.5 around 5 years ago. It's a Strada that the owner had made "sporty" with clip-ons.

I was so excited but within 40 miles, and on my way home from registering the bike with the state government, my clutch went slack, I heard a pop, the chain flew off, and I rolled to a stop. Okay, no problem. I came pack with my pickup, loaded the bike and took it home. I thought I had simply broke the cable and something came loose and hit the chain. But what actually happened was the mounting where the clutch arm attaches to the case on the right side (the flywheel side) had broken free. This seems like a major stress point, and I have researched for others with this problem, surprisingly with no luck. Anyway, I have other bikes but over time I try to think of some way to resolve the problem, which seems so small, but has completely stumped me. Friends have told me this is unweldable, that you would never get a good weld and the heat might distort the case. In any way, I would have to strip it down completely to do this. I was trying to avoid that, but if that is what it takes... the other option is to try to find some new way to mount the clutch arm, or to try to find a replacement case - heck, even a replacement engine.

This is a picture right after it happened. I have since cleaned it all up. A portion of the mount for the clutch rod/pin also came off too.
So I need advice. Has anyone seen this problem before?
Is it un-weldable? Would I need to strip it to the case to have it welded?
What about bolting the clutch arm from the inside of the case, or some alternative solution?

I appreciate any advice. 5 years of looking at this bike, wanting to ride it again! -Tom, Oakland, California

The picture shows a section of broken chain guard and the break is very dirty. I suspect that the bike has thrown a chain in the past and the release arm boss damaged. The other thing that might have caused it is if the adjuster bolt had been tightened in too far. In either case it's taken until now to finally fail.

The case is probably weldable, but probably only if stripped down. I'm sure Alex at NLM would have had a go. He could weld the crack of dawn if he had the right filler rod.

Probably the simplest solution is another set of cases. They're reasonably common and it's an easy engine to rebuild. Sign up to the Morini email list, there are plenty of American Morinisti and I'm sure someone can help you out.

http://www.smoke.com.au/~ic/morini-list.html

A good welder could fix it no problem, assuming it was disassembled. A *really* good welder could do it in place, assuming you removed anything rubber, ie the sprocket and shifter seals, before the job was done. But there are few welders that good, and many who *think* they are that good, so I'd plan on pulling the case apart.

In your picture I can see only the one mounting flange. That one looks like a prime candidate for drilling through the case right where the clutch arm mount bolt hole ends, tapping at whatever the clutch arm pivot bolt is, then through bolting everything place using blue loctite like holy water. That should hold OK, if I understand what I'm looking at.

Sam

Thanks for the responses so far - I went downstairs to look at the damage but can't see the broken chain guard section - maybe the photo just makes it look that way, or maybe I don't know what I am looking for. I am going to take a couple new pictures now that it is cleaned up, and post those. But suddenly it made me think, could the chain have flung loose and caused the break For 5 years I have assumed it was the stress from the clutch mounting itself.

In either way, I will prepare to disassemble, since to get any decent repair it sounds necessary. I don't want to burn up other components when someone tries to weld it in place.

Hello, really new to the Morini love, but can help you if you would like. as a toolmaker and welder as well, If you would like me to perform the repairs for you, I would be happy to put this legend back on the road, and be very reasonable at that. I am located in Ct. so your dealing with only shipping at this point. Jeff

thompson_owen wrote:Thanks for the responses so far - I went downstairs to look at the damage but can't see the broken chain guard section - maybe the photo just makes it look that way, or maybe I don't know what I am looking for. I am going to take a couple new pictures now that it is cleaned up, and post those. But suddenly it made me think, could the chain have flung loose and caused the break For 5 years I have assumed it was the stress from the clutch mounting itself.

In either way, I will prepare to disassemble, since to get any decent repair it sounds necessary. I don't want to burn up other components when someone tries to weld it in place.

In your second picture there is a rib (that I called a chain guard) that follows the radius of the sprocket. Above the clutch rod boss the rib is intact and you can see the radius on the edge. to the left of the boss it looks as if it's been broken off, but perhaps it is just grease/dirt.

Looking at the pivot boss more carefully, it looks like a clean break, not a crack that progressed. It may well be that the chain took it off. More often it damages the pushrod boss and I remeber Alex telling me of repairing one with chemical metal as a temporary fix. The same machine came into the shop a few years later with the fix still doing it's job although with some oil leakage.

A previous owner of my 350 Sport had a chain problem that did very similar damage (almost) plus damaging the case. Was neatly glued together with plastic metal or similar goo and nicely hidden by oil grease etc :roll: . Lasted for a while and then the clutch stud gve up the unequal struggle when nudged by a chain that was a bit worn. Had cases (including damaged bearing housing internally) welded up and machined by NLM and been fine ever since.

Clearance twixt chain and case is very tight - even looked at going down one tooth on the gearbox sprocket (and changing rear to suit) to give a bit more clearance, particularly if running a 530 o-ring chain.

Anything is fixable given a few (!!!) pennies - but would recommend a complete strip down to look at internal damage as well.

Here are a couple new pictures I took with my good camera and macro lens. I think this shows the damage better. Here is a broader image
And here is another detail image:

Thanks for the ideas. What I am hearing is that YES it is weldable, but it is wise to strip it down completely to isolate the case that needs repair and take that in to the shop. Of course, the metal epoxy glue is always tempting but I just can't imagine it holding for long under all the stress of the clutch arm -Tom