Securing the engine without it moving

[gokartmozart]

Okay, I just upgraded the engine on my mini bike, from 3hp, to a 5hp. Oh, what a difference! In both cases I tightened down the little buggers pretty firmly, or at least I thought I did, but these engine keep sliding around. Surely they are under great strain pulling on that chain. The mounting plates holes have some adjustment, but am I just not cranking down on them enough or do I need some kind of friction material. After a ride around the yard I can see the engine has pulled to once side. Is this a common problem?

 

[Russ2251]

I've only heard of this happening.
With 2 karts and a mini bike (with various power plants) I've never had the problem.

 

[KieranM]

no its not common, what engine do you have

 

[Kaptain Krunch]

Use nylock nuts, and good washers and use your muscles. I have never had this problem.

 

[Kenny_McCormic]

Get some good grade 8 hardware(so you can torque it good), use lockwashers and washers.

 

[gokartmozart]

Okay, so it is me....just a matter of really going to town on those bolts. Will do with the grade 8's.

 

[SpyGuy]

Loctite is your friend!

You may also want to consider adding another bracket to the engine to help hold it in place better.

 

[Blazkowiez]

Make sure you've got washer underneath and lock washers and or good lock nuts. Not just regular nuts and bolts.

 

[Russ2251]

I use keps nuts.

 

[SpyGuy]

Big set of nuts there, Russ ....

 

[gokartmozart]

Okay, I placed some rubber underneath the engine, and tightened it down, but now the rear wheel moved. I guess the chain pulled it forward on the one side. Is it I just am not tightening these things enough?

 

[Blazkowiez]

Why did you place rubber under the engine? Regular washers, lock nuts, lock washers, bolts etc can do the job just fine.

What do you mean the rear wheel moved? Typically when you see that the wheel is slanted it means you hit something.

 

[Russ2251]

Big set of nuts there, Russ ....

Much bigger than yours I'm guessing.

Get some good grade 8 hardware(so you can torque it good), use lockwashers and washers.

...and torque to 25ft. lbs. Do you have a torque wrench?

 

[gokartmozart]

well, I placed the rubber under the engine to help with vibration, and also to aid the engine staying in place. So far it has not moved.

The rear wheel has pulled to the chain side. Now I noticed when I tighten the axle bolt the frame compresses. My axle adjustment bolt then starts to touch the sprocket. I assume I need a washer in there? Otherwise I run out of adjustment.

Without a suspension these little bike really take a beating. The jerky action of the centrifufal clutch does not help.

What is the life of these chains?