Pivot bolt through the motor question!

[250Renvy]

So admittedly the newer 450 machines have not been out that long compared to the overall length of atv's being around, but I'm wondering about the pivot bolt going through the motor over the long term.

Often when you find an old 250R and the bolt has not been greased the pivot bolt will be seized in the swingarm and it needs to be cut out. This isn't such a big problem because it doesn't go through the motor.

So considering the motor is aluminum and the bolt is steel, could the bolt corrode inside the motor case and seize and be stuck for good? Would you have to then replace the case or machine it to get it out? If it's not properly greased does the bolt hole get worn because of the friction?

I'm trying to setup a motor and trying to decide if I should mount it through the motor or do something else.

[Scro]

I've never heard of the bolt being seized in the cases. I've only heard of them seizing to the swingarm pivot points. They can be cut out if this happens like you were talking about.

[86 Quad R]

i have ran into this sinerio with an old ATC250R a while back. the front engine mount bolt had never been removed and was fused in there SOLID but after a long while and some patients, i managed to get it out. so yes, it can happen. a prevenative is to assemble the unit useing water proof grease and/or mod the oem(hollow) bolt so that you can apply grease. the trick is to drill a small hole in the bolt in the area where it resides in the cases aswell as where it makes contact with the swinger pins. everytime you lube the bolt it lubes all the important areas. hope this helps. :cool:

[250Renvy]

Originally posted by Scro
I've never heard of the bolt being seized in the cases. I've only heard of them seizing to the swingarm pivot points. They can be cut out if this happens like you were talking about.

That's what I was wondering. The old motors weren't mounted that way, the new motors have only been out for a few years so the likely hood that they would have seized so soon is unlikely.


I guess I'll just have to make sure it's greased enough. I may try finding one or getting a greasable bolt made, that would probably help.

[deathman53]

400ex's are done this way, yes, I seen the bolt seized into the motor cases. Many dirtbikes are the same also, going back to the 80's. The answer is simple, remove the bolt, anti-seize and re-install every few months. Thats the only way that bolt won't be a problem. When buying a used bike, always assume the bolt is stuck, better than 1/2 the time it is. Lsr sells a zinc coated bolt, it supposedly won't seize. You can also Moly-coat which is a Teflon coating the bolt, ktm's come this way, front axle, rear axle and swingarm bolt are like this.