As the title says, i just finished putting in a YooHoo belt on my 10th AE, and now it vibrates badly OVER 4500rpms or so. Is it just the looseness in the belt flopping around? Thanks

 

I doubt it. The extra tention on the front pulley might have spun the bearing in the front stat gear. The yahoo belt is not a good idea because of all the extra stress it puts on the very front of the pulley...

 

IMO it's a nasty little hack that is very likely to damage bearings. Do it right and get a dual-belt pulley.

In the mean time cut it off and see if the vibration goes away.

 

Does the yoohoo belt really put much more stress on the main pulley than running 2 accesories?
I'm running the pineapple alt relocation kit and I just bought a yoohoo belt as a safety measure but i haven't installed it yet.
How many miles were on these engines when they threw the bearings?