Supercharger belt tensioners

[jkarran]

Anyone got any ideas on suitable SC belt tensioners? I just did some worrying calculations on belt speed and tensioner rpm

at 12,000 crank rpm (dont ask! bike motor but the problem applies to all engines to a lesser extent) with a 3" crank pully and a 2" tensioner the tensioner is running at 18,000rpm.

A quick check of the catalogues at work and I could find very few grease lubricated bearings that would stand that.

I had thought of maybe Civic typeR or Swift Gti cam belt tensioners but of course a cam belt runs much slower than that. Mine is ~47m/s, Swift Gti ~23m/s @9Krpm

jk

[stuartgallafant]

wouldnt you be able to use a tensioner off a motorbike?

or even make the pulley larger so it spins slower?

[jkarran]

Bikes use enclosed chains in hard plastic guides.

Large pully is an option but space and weight is at a premium, either that or make one and fit decent high speed needle rollers. Just thought I'd see what suggestions others had, it's always useful to get a 2nd and 3rd and... opinion

jk