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strat6v
March 21st, 2006, 11:23 AM
Could one of you knowledgable types explain why, on the Hawk,the rear caliper is fitted in front of the hub in a leading position and not in a trailing position? With my limited knowledge of how forces work, in a leading position, when the caliper grips the disc would the rotational force tend to pull the strut down/unload the suspension? and vice versa, compress the suspension if it was behind the hub? Is there benefit to be had with one or the other?

John.
chris.richard
March 21st, 2006, 11:33 AM
I'm sure (though I can't explain why :confused: ) that the position of the caliper can have no effect on the suspension - the action and reaction are both contained in the unsprung parts and therefore only rotational forces are left. Or something... :rolleyes:
strat6v
March 21st, 2006, 12:07 PM
It affects bikes, shouldn't be any different?
guy mayers
March 21st, 2006, 01:06 PM
There is a practical reason for putting the calliper on the trailing edge of the disc, imagine the route the handbrake cable would have to take to get to one mounted on the leading edge.....
Guy
strat6v
March 21st, 2006, 01:33 PM
Guess that all depends on the caliper.

I'd seen a few cutaway pics of the strat showing a four pot behind the hub instead of at the front nearest the fuel tank. Just thought there must be a reason. :confused:
mogul_x
March 21st, 2006, 01:47 PM
The calipers should be fitted in the same orientation as those on the donor vehicle to ensure proper operation of the handbrake. I'll have to check mine, but I think the Alfa 164 brakes were mounted forward of the axle centerline.
pimms
March 21st, 2006, 10:25 PM
The calipers should be fitted in the same orientation as those on the donor vehicle to ensure proper operation of the handbrake. I'll have to check mine, but I think the Alfa 164 brakes were mounted forward of the axle centerline.

Just checked the operators manual of the 164 I had and it shows drawings of the ABS with the rear calipers in front of the discs.
mogul_x
March 22nd, 2006, 06:10 AM
Pimms,

Thanks for the confirmation! I checked mine last night when I got home, just to make sure my memory wasn't playing tricks, and saw the same thing. My Lancia Montecarlo also has the rear calipers forward, but the Camaro has them aft.

I still can't figure out why there'd be a significant difference in suspension loading due to caliper position, though. I keep coming to the same conclusion that Chris did. Can you explain that in a little more detail, John? I don't know much about motorcycles.