Broken motor mount on Head

[FFRDave]

Yeee-Haaah !!!!

I finaly got to go riding for BOTH DAYS OF MY WEEKEND

Believe it or not, I didnt notice the broken mount till the end of my Sunday ride.

The break is on the bracket where it fits onto the head, but only on the right side bracket. The upper bolt travels from left to right through the frame, just as the head bolt does. Then the right side bracket goes on and finaly the nuts (upper & lower) to hold it all together.

I removed these brackets when i did my head squish measurements. I noticed that those nuts were awful tight, so when I re-assembled everything, I made sure to really tighten them down good.

I have re-ordered a full set of brackets (both sides) and bolts (upper and lower) with the correct nuts. I am thinking that I may just copy the brackets and make my own out of a stronger material (stronger than alluminum). I have also considered some type of shim or hard rubber washer to place between the head and the bracket in order to dampen the vibration.

2005 Gas gas EC 250

 

[gasgasman]

Those head braces can break if the head and frame mounts are different widths.
The braces would bend when you tighten them up,causing a stress crack to form.
If the braces are not parallel, you can add washers to make up the difference.
Check your other motor mounts for proper torque.

Rubber mounts may be a moot point, since the rest of the motor will be solid mounted.

 

[cdn280]

Rubber mounts may be a moot point, since the rest of the motor will be solid mounted.

Especially when the bolts are torqued and the rubber is flattened. It is then useless as a vibration damper. I have tried the rubber washer trick on a few parts, like a fuel tank holding bolt and it worked to a degree, but it can only be tightened a few ftlbs or it won't work at all.

 

[FFRDave]

Im gonna make a new set of brackets out of steel. I am hoping that they will be more resistant to fracture than the alluminum. The break was across the bolt hole. Then, I think I might use some Poly or plastic washers/shims to even out whatever mis-alignment there may be. The nuts have teflon rings in them, so I am thinking that they shouldnt need a zillion Ft.-lb. of torque anyways.

I will definatly check the other motor mount nuts & bolts.

I am mostly just bouncing these ideas off of you guys in case someone knows something I do not.