Rear mount studs broke, any good fix???

danlandberg · May 21, 2010

I think the front adapter mount is allowing too much flex! I square the rear mount to the seat post then do the front mount. But the rear mount keeps dropping down the tube, even with hose clamps above & bellow mount spacer! I'm going to remove the engine today, repair the rear stud AGAIN

(3rd time on this engine) only one stud this time! And I'm going to remove the pressed metal clam shell piece from the front mount to let the front mount bolts to hit the frame!

this might eliminate flex. The front adapter mount I made for my Royce Union was flat plate and did not allow any flex!

I don't think I'll be riding soon though, quit running again

Went on a 30 mile ride yesterday got home and then went to the store 1/2 mile away and it quit running

the MAG went again! Going to put a meter on it today & check ohm readings. + fix the flat rear tire! I'm am so mad at this piece of

I am about ready to throw it off my second story balcony!!! That would be the easiest way to get it down stairs

This MICARGI / Flying Horse piece of

AussieSteve · May 21, 2010

Man, you're not having much luck.

Al.Fisherman · May 21, 2010

Dan, you mentioned that the rear mount can slide down the tube, if there is any movement between the front and rear mounts to tubes the engine WILL move (basically rotate) on the tubes thus putting a strain on the 6mm studs. 50 inch pounds really isn't enough to (to me) to keep this from happening. This is the reason I made a small "L" brace to mount between the clutch housing and seat tube. The bracket is secured to the engine case and engine torque keeps it in place. I have a ole frame at this time and is scratched so I didn't protect the tube. A small piece of rubber can be glued to the tube between the "L" bracket. You DON"T want ANY movement between the engine and frame. I squared the engine up on the frame and "made to fit" the bracket. All my 6mm studs are torqued to 50 inch pounds and without the "L" bracket the torque will pull the engine to the left. I have had the engine rotation problem on every build I have made.

danlandberg · May 21, 2010

Problem after Problem

This bike has given me more trouble than my other two builds put together!! Question, how much end play can you have at the crank after break in? I have about 200 miles on this engine, and only about 60 miles on the first engine (before stud problem). I have no play in that one! I removed the MAG & can move the magnet in and out about 1/4 in. Not up & down or forward / backward. So the bearings seem to be OK.

I'm getting way off the spec ohm readings on this mag now! Blue to black = 454 k ohms & black to white = 221.6 ohms. At first, now I get open line with every test!

That's using a Blue Point (Snap-On) digital meter! No one has posted a reading for the CDI (that I have seen) But I get a reading of black to blue = 4.61 m ohms & black to spark plug wire = 6.81 k ohms, blue to spark plug is open line! What is going on with these mags???

Need input!!!......................................Dan Sorry I got off topic!

Al.Fisherman · May 21, 2010

Sorry, Dan I can't help on that one. Out of 5 coils I've worked with I had problems with only one and that was within 3 days of purchasing...1st or 2nd day of riding. You got me by the "you know what".

themotorbikeguy · May 21, 2010

danlandberg said:
I think the front adapter mount is allowing too much flex! I square the rear mount to the seat post then do the front mount. But the rear mount keeps dropping down the tube, even with hose clamps above & bellow mount spacer! I'm going to remove the engine today, repair the rear stud AGAIN (3rd time on this engine) only one stud this time! And I'm going to remove the pressed metal clam shell piece from the front mount to let the front mount bolts to hit the frame! this might eliminate flex. The front adapter mount I made for my Royce Union was flat plate and did not allow any flex! I don't think I'll be riding soon though, quit running again Went on a 30 mile ride yesterday got home and then went to the store 1/2 mile away and it quit running the MAG went again! Going to put a meter on it today & check ohm readings. + fix the flat rear tire! I'm am so mad at this piece of I am about ready to throw it off my second story balcony!!! That would be the easiest way to get it down stairs This MICARGI / Flying Horse piece of

haha i wish my motor was that clean

AussieSteve · May 21, 2010

Dan, if you can get at it, it's worth checking the solder joint where the black wire joins the coil. It might need re-soldering. Check the blue and white too, but since both readings are affected, the problem is probably in the black wire connection, or possibly even a break in the black wire. If it's none of these, the coil is kaput.
Your magneto resistances should be much lower. From memory, the blue should read about 200-300Ω and the white should be about 3Ω.
Your CDI is probably OK since it sounds like the magneto coil is the problem.
(I don't have any test readings and even if I did, external measurements mean very little with CDIs. There are a number of internal components that could fail without affecting the external resistance values. The best test is substitution.)

¼" end-play for the crankshaft sounds pretty excessive. I wonder how the big and little end bearings like it? And the primary gear on the RHS end of the crankshaft.

danlandberg · May 22, 2010

Guess I'll pull the clutch cover off and have a look see. might spot something wrong! And check the black wire for a break (open). The black wire is not soldered to anything,it is grounded with a MAG mount screw!

I might pull it apart. And put the first engine on when I can get another MAG to put on. ( & CDI, just in case). And got to mod rear mount. (on first engine) Prey

I can get something to work! I'll have to go back in my E-Mails to see what date I bought these things (6 month warranty) But I don't want to do any more business with B.B.! :snobby:

Two dead horses in less than 6 months? Must be a disease! Mad horse fever or something.

I have only bought engines & add on parts from 3 different Co's.

Think I'll try DAX for the MAG & CDI this time.

Or does anyone have a suggestion on a Co that sells QUALITY parts for these things?

PatrickW · May 22, 2010

Rear Studs Snapping...

Dan, I have been following your thread from the start, and I thought I might have had a solution to your 'rear mount stud' problem...but when you blew off at the poor kid, I figured you weren't worth helping. There are several old drag racing tactics that I think would work, we were always snapping rear motor mounts.

But, since you apologized, if you will post two (2) pics of your rig, motor mounted, from several feet away so I can see the engine on the bike, each side, so I can see both sides, I think the fix will be obvious and simple. Do it...first advice is free.

danlandberg · May 22, 2010

Sorry if I was rude in any way, to any one! This thing has got me so mad

It is possible I take it out in the wrong way & wrong time

They are not the best pics. You can't see the angles I'm dealing with. Other pics I tried to add, got an upload failed notice!

Rear mount studs broke, any good fix???

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