Broken motor mount studs

You should be able to buy metric studs or metric threaded rod at a local fastener shop. My engine has 6mm studs with 1mm pitch. The back ones are longer than the front but I didn't measure lengths cuz I didn't want to take them out.

If you get threaded rod you should have a good way to cut it and clean up the threads on the ends. A good place to get it online is McMaster Carr if you can't find it locally. Their site is http://www.mcmaster.com/ . In the search window just enter "metric stud" and you'll have choices of diameter (M6), pitch (1mm), material, grade (B7 is alloy and has good tensile strength), and length. If you know the length, ordering the right ones would be easiest but they have a 1meter length rod that would do all of them with about 30" left over. Bolts will work too but a stud is better. When you put the new ones in make sure you put some locktite on them.
 
If the studs are broken off flush, a dremel with a cutting disc can cut a slot in the stud end. Then use a standard screwdriver to back it out. If its below the surface take it to a machine shop. The studs are a standard item carried at most auto parts stores, but allen head cap screws M6 seem to be stronger and less likely to back out when loctite is used.
 
Lock tight is our friend :) after you put the motor together and everything is running go back and lock tighte every thing you can ....you can make a motor mount out of a pc of wood and it will work but you need to have those studs

Cookie
 
same thing happened to me i just replaced the mount and studs works fine now but i do check on it more often
 
motor mount

I notice those two bolts have gotten lose on me I just re-tightened them. Need to put lock tite on them.
 
just tap new holes 8mm will work fine i had the same thing happen to me the alum case will handle it fine
 
this also happened to my mounting studs except my studs snaped inside of the engine. luckly i was able to easy out the broken threaded rod and replace with 6mm bolts from a local auto parts store i bought nice heavy duty steel bolts and reinstalled with some locktight I havent had a problem since. Now when ever i buy a engine to install on a bike i always remove the studs they come with the kit and replace with nice steel bolts and some locktight , i have found that the studs that come with the kits bend and snap very easly. also make sure you try to tighten each side on the monting bracket close to equal.
 
I go to the local ACE hardware store and buy metric all-thread rods. Yes, they aren't as strong as studs but their softer composition actually allows them to stay snug a little longer upon torque down.

I don't order online, I would rather be riding then waiting for UPS guy to show up with package.
 
Back
Top