I keep breaking the bolts that mount the top of the engine to the frame point underneath the tank. No matter what quality hardware I use (grade 8 included) it keeps brekaing bolts. The bike seems to shake less once the bolt breaks so I just ride without the top bolt on it.

The only advice I got that makes sense is that a mechanic said that if en engine is mounted inproperly and not shimmed correctly that it might casue this problem. Unfortunately that guy moved to Oregon and noone around here can work on Shovels.

Any thoughts?

'75 FLH

 

there is a post a few down that talks about aligning the motor and wheel ect. It also talks bout shimmin motor mounts take a look Dusty

 

my .02 from an old HD mechanic that worked at Sam Arenas in San Jose... Engine must be in the frame and have nothing else tightened to it (inner primary). Loosen bolt at topwhere it mounts to frame, loosen four bollts (front and rear) that mount the engine to the lower part of the frame.

Having done that tighten the rear mounting lower bolts to the correct torque specs. Use a feeler gauge and measure spacing between engine and frame where front mounting bolts go. Make spacer(s) to eliminate the gap (if any)

Having done that, tighten rear first and then tighten front lower mounting bolts to specs.

Next measure spacing between upper mount to frame. Use washers to make difference or make a spacer to eliminate gap. With that done you should be able to tighten the upper motor mount to specs.

 

yep, thats the way it's done. if you don't you'll keep breaking bolts or worse you'll break the case's. ouch.

 

You've got to get those cylinders tied down. They are sitting ther flexing back and forth, left and right and you will eventually raise your cylinders due to the base studs being pulled from the cases. Follow the instructions above. A shovel cylinder can grow a 1/16th to an 1/8th from cold to heated up.
I inserted a previous post of mine and mixed it with another good post.


"Set your engine and transmission in the frame. Put the bolts in and leave them a little loose. Mount your inner primary to the motor and trans and torque them to spec. Look at your motor and see if the motor is sitting on the frame mounts flat. If one of your motor mount "ears" are not flat on the frame, it will eventually break under the vibration stress. If you have to, finish that beer in your hand, and make some shims out of the can and shim that motor mount. Now tighten the engine and trans bolts and torque to spec."

If you are running a stock frame, this is all you need to do. Just make sure when you mount the rear wheel that the mainshaft spocket and the rear wheel sprocket are aligned. A stringline will work. Take your time now, and you will be rewarded with long service.

Engine must be in the frame and have nothing else tightened to it (inner primary). Loosen bolt at topwhere it mounts to frame, loosen four bollts (front and rear) that mount the engine to the lower part of the frame.

Having done that tighten the rear mounting lower bolts to the correct torque specs. Use a feeler gauge and measure spacing between engine and frame where front mounting bolts go. Make spacer(s) to eliminate the gap (if any)

Having done that, tighten rear first and then tighten front lower mounting bolts to specs.

Next measure spacing between upper mount to frame. Use washers to make difference or make a spacer to eliminate gap. With that done you should be able to tighten the upper motor mount to specs.


I think both of us are pretty close to each others idea.

 

Use the above suggestion for shimming engine to frame,you are lucky so far to only be breaking bolts and not engine cases.I would also check your frame for a break,espon l/h side,just below swingarm attach area in radius section.This area was beefed up by factory by adding plate material but can still break if bike is rompedon.Topmount could be carrying this load if broken.

 

Thanks guys. Now I jsut need to either find someone to do this or get brave enough to tackle this. I know it's not rocket science, but I jsut get a bit nervous working on something that doesn't surround me with sheet metal and a frame!