Bentley Drivers Silverstone

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Bentley Drivers Silverstone

Post by Forumadmin »

The team took the Jup for a Fiscar race having spent many hours improving the car since the racing in Charade, Clermont Ferand.
After a few laps of Qualifying by Harry, Chris took over to try to get a good time but spun the car and on the next lap the clutch exploded putting large holes in the clutch housing, holing the radiator and putting dents in three panels of the bonnet. Chris managed to coast back to pit entry. The transmission locked solid so here you see us raising the back axle in an attempt to get the car back to the garage. The recovery truck arrived and hoisted it onto a flatbed.
Examination yesterday revealed the cause was the pressure plate had fractured in three places where the pin for the actuator arm locates. This is the thiness part of the plate and has to endure the large bending moment delivered by the springs on either side . The many heat cycles and fatigue from the loads way over the design limit means we need a new clutch design.
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Nick Webster
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Re: Bentley Drivers Silverstone

Post by Nick Webster »

Technically that's quite an interesting failure, though I do feel the team's pain. Do you know if the broken plate is a standard item or a specially made casting? In any case, I am assuming it has been thinned down to reduce weight.

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Re: Bentley Drivers Silverstone

Post by PJGD »

The 7.25" Borg & Beck clutch was a widely used component back in the 1950's. I would be surprised if a similar sized diaphragm clutch cover plate was not available as a replacement somewhere.
Philip Dingle
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Re: Bentley Drivers Silverstone

Post by Forumadmin »

Nick. It was standard and not modified.
Philip, Yes we have researched and there some alternatives. A full racing clutch is what is required as already used by a couple of Jowett racers.
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