Originally Posted by iHop
. . . Drone’s one looks like the same M72D frame/mounts as what I got from DMC almost 3 years ago. I’ve since switched mine to clevis/eye and added a front mount to the bike and tub. I did this because, like Drone’s rig, the two mounts on the sidecar frame are very close to each other toward the rear and provide little support on the tub nose. On mine the front of the tub flexed down a lot. Eventually (less than 10K miles) the center mount snapped out of my sidecar frame along with a hunk of the frame tube
(click). So the spot I’d keep an eye on isn’t the lower mounts, but where the front strut attaches to the sidecar frame.
I have to agree with iHop-- I think I have to keep a close eye on the upper struts where they mount to the sidecar frame. Right now they're fine--no cracks. If one breaks, well then at that point I'll look at other options.
I also wonder if because my rig runs so straight and true, with no wobble or shake, if maybe my struts won't develop metal fatigue as quickly as some other rigs where the stresses and strains are more or less constant.
It's kinda nice living only 30 miles away from the DMC shop. If I have any troubles, it's not a big deal to get the rig looked at. I might even take it in there next month to brainstorm with those fellas. The problem with the 1150 is that there's no good place to attach a strut forward of the cylinder head. It can be done, but it would involve so many extenders and angles and joints that I'm not sure how much good it would do.
Edit--Yeah, it did break, in June of 2012 after maybe another 10,000 miles, many of them on dirt and gravel. This rig has not been babied! Here's a pic--
But the struts are pretty robust. I had no trouble driving another 300 miles with the broken strut to Enumclaw where DMC was able to fabricate Jay's retrofit solution for this problem. Sorry for the bad pic--
Basically, they weld a collar around the frame then drill it and weld in a solid mounting post that's welded on the top and bottom of the frame. Much stronger than before.
In defense of the DMC design, I must mention that the P.O. had mounted the car totally wrong (both lower struts upside down) and the frame got 4500 miles of abuse before that situation got fixed. Jay told me that the upside down strut mounting put extra strain on the upper front strut, and he warned me to keep a close eye on it six months before iHop mentioned it in the post above.