Rear mount studs broke, any good fix???

My exact feeling also....I got to try something else.....
It will be cheaper to either buy (front mount support) a pre made or have one made/make now, then go through a broken stud or even the case. Personally I wouldn't ride that bike with the engine mounted like that...not even around the block, but that's me.
 
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Wow the stud length in those pictures are very long. I think the longer you are away from the motor the more shock the studs must withstand. Is this because of the frame angle of the bike? We took out all the factory studs and replaced them with stainless bolts. Also we mounted the engine as far down the V as possible so the front and back mounts were flush with the frame tubes. This transfers the weight close to the bottom and provides balance and takes out most of twist of the engine with the pull of the chain. There is a lot of mechanical dynamics that goes on here. Our engine was a slant black with great mounts front and back. Much wider in front to fit to the front vertical frame. Here are two pictures of our mounts. Notice the thin rubber pad in front to help reduce vibration.
Good luck in your build.

Vic and Danny

I don't feel that the length of the studs make any difference as long as both front and rear mounts are mounted properly (flush ..both mount and clamp). Are not over torqued and a brace to keep the engine from rotating on the tubes. From what I see and I could be wrong..your front mount is not flush on the tube, and I'd like to see the rear mount and carburetor angle since you dropped the front. Not all frames can accommodate a engine that way.
 
The length of the studs should not matter, as long as everything is square! But with the MICARGI M50, that is not possible! I have'd looked for an online angle calculator, But every sight I found needs one of the angles to be at a 90* angle to start with! The seat post to top tube would be the closest! Any one know of a sight I can look at? I'm to old & dumb to do math myself.LOL I need a sight that will calculate any demention I put in, to determine every angle. And any configeration.
 
It will be cheaper to either buy (front mount support) a pre made or have one made/make now, then go through a broken stud or even the case. Personally I wouldn't ride that bike with the engine mounted like that...not even around the block, but that's me.

Right again, Al. I went back to mounting engine to the frame instead of frame to the engine...the way I had for the last 6 months!


If it's not broke and you screw with it long enough, it will be.
 
I just ride the thing, Broke or not! It's running now, got the MAG & CDI yesterday. Piston Bike is fast on the shipping part. Only rode about 10 miles so far! No mount probs yet! But it's too early to tell. Hope everything holds up! Still probably need a torque stop on this thing. It has a bit of power for a 66cc peddle bike!
 
Dan, go to Home Depot/Lowe's or the like and buy a shelf "L" bracket. Enlarge the mountimg hole to 6mm and cut to fit. I used 14 gage angle iron, cut, drill and install.
 

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I was going to post something along the same line, but just didn't get to it. I find it totally amazing what sort of usually quite "Costly and Fancy Machine Work" we can find on the shelf of our local hardware store for less than a buck. Not just in this situation, but in many cases where we dream up some esoteric and elaborate remedy, when the 'quick and dirty' fix is sitting right in front of us.
 
I would love to know what percentage of mb's have these breaking stud problems. I have two mb's with quite a few miles and have never had any of these problems with the studs. I believe that most problems are too much torque, I have never used a torque wrench on the mounting studs, not that I'm recommending this practice. I have a lot of mechanical back ground with cars and motorcycles.
 
I have only used the stock mounting studs that came with the kit. Are the grade 8 a little on the brittle side, another guy from the other mb site said they can be, wondering about this upgrade.
 
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