Rear mount studs broke, any good fix???

The ACE HW store caries 6 x 1.0 Allen head. (black). Which are nicer than the Philips/std head screws they use!:sick: I don't want to use rubber because the Flying Horse engine is smooth running, when it runs. (little vibration) and the clam shell spacer mount is all ready to tight to the seat post, I would not even get an old piece of inner tube in there! :unsure: I think it's a torque issue that's causing stud failure. Going to add a torque stop like Al Fisherman & A Steve use! And see if that cures the problem.:rolleyes: As for attachments I'll PM you!

Dan, If you need either a couple pieces of 6mm or 8mm grade 5 all thread with locking nuts just let me know how long they need to be. I can make them and in the mail either today or tomorrow.
 
This is what I'm trying this time. Notice the bend in the front mount? It did not even feel tight! Going to add angle iron for strength. The studs are 4" long, and are left over from a GRUBEE build I did last year along with the mount spacer! The small piece of strap (held in place with a hose clamp below mount) is there so I MAY not loose the spacer & flat stock if stud failure occurs again :unsure: That's IF I catch it in time! And dissecting a MAG :whistle: Looks a little more tedious than I want to deal with at this time!:cry:
 

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Stud Length

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
 

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I have not tested this mount system out yet! Waiting on MAG & CDI to get here! And yes the bike angle is the problem. I have the over sized front mount as flat sa possable to the down tube & rear mount is as square & low as it will go on the seat tube. This is a MICARGI DIY kit from B.B. they are junk!!!
 
Motor mounts

Ya its the toughest job in mounting these engines. As you can see from our pictures we took the chain guard off the pedal side so we could lower the engine the max amount. This gave us another couple of inches to lower it more.
When you get the engine low like that the muffler clearance also comes into play. Instead of trying to bend that muffler like those instructions tell you to do just elongate the holes in the muffler flange. An 1/4 inch at the top can give you 1/2 inch at the bottom to clear the frame and the crank.
Good luck with your engine.
Vic and Danny
 

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This is what I'm trying this time. Notice the bend in the front mount? It did not even feel tight! Going to add angle iron for strength.
The studs are 4" long, and are left over from a GRUBEE build I did last year along with the mount spacer!

Dan, that rear mount looks real good!! Just wondering if you had to grind out those spacers to fit seat tube? This is pix of my crummy rear mount which I do not like!!:sick: Best I could do with junk Ive got:sick::sick:My F mount should be OK.

http://www.motoredbikes.com/attachment.php?attachmentid=26322&stc=1&d=1274828380
 

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I did not have to do any grinding! Two of the three mount spacers I have. fit tight! I used the tightest ones! :unsure: This would help a better none slip grip! And maybe help stop any twist at acceleration! Will not know until the MAG & CDI get here, (so I can go on a test flight) :D Took the engine components off, so I could ride it as a bike. except for (clutch lever, chain roller bracket & 42T rear sprocket) :unsure: I'm going to put the first engine back on, because it doesn't have as much crank end play. And it is just at the end of break in!
 
This is what I'm trying this time. Notice the bend in the front mount? It did not even feel tight! Going to add angle iron for strength.

Dan, that rear mount looks real good!! Just wondering if you had to grind out those spacers to fit seat tube? This is pix of my crummy rear mount which I do not like!!:sick: Best I could do with junk Ive got:sick::sick:My F mount should be OK.

http://www.motoredbikes.com/attachment.php?attachmentid=26322&stc=1&d=1274828380

That rear mount just might hold up but my personal feeling is it's a disaster waiting to happen... Mount the engine to the frame...not the frame to the engine.
 
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