I've read that you shouldn't be able to twist the belt more than a 90 degree angle when gripped between the forefinger and thumb. I've tightened mine such that when I twist it it goes to like a 45 degree angle. Is this too tight?

 

90 should be enough... I just checked mine yesterday and it was more than that... I've never had a problem with slipping but I only have the 3.6" pulley, though. I wouldn't have it too tight to be on the safe side.

 

Yea, no more than 90. I have the 3.33" and I made sure mine was at 90. I did hear something about someone saying les than 90 for those who have even smaller pulleys, but I can't guarantee that. Mine seems to be holding up fine (knock on wood).

 

The smaller the pulley, the less traction area for the belt, and you are driving the blower faster to boot (more power required to turn the blower). So smaller pulleys are going to need more belt tension to keep from slipping.

 

So with the 3.33" will a 45 degree bend be sufficient or do I have it on too tight? Previously I was judging by the slippage noise. If it was still noisy I'd tighten it a bit more. I have a feeling that I may have overtightened it which lead to the beginnings of bearing failure.

 

One reference I have on the subject Supercharged mentions tightening till the belt is tight, then tighten some more. Highly unscientific, but the implication is that it is better to be too tight than not tight enough.