A question about Steel vs Stainless steel fasteners..

The values should be ~0.20 for steel & about 0.3 for stainless into alloy, that's a 50% difference.

Thanks, thats a useful link..

So (in theory anyway) if the manual says I need to tighten it to 44NM with the OEM capscrews I would need to go to 66NM with the stainless to have the same amount of force..

If the pretensions the critical/limiting factor. Obviously if the bolt's close to it's limit then that'll snap it, so an easier solution is a bit of molyslip & use the original value. You probably don't want to use stainless on anything where the pretensions critical as the fatigue lifes lower.

Bolt torques are set generally so that the bolt is being slightly stretched, without going into inelastic extension. Got no idea of how this compares for stainless VS boggo steel.

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember WipeOut saying something like:

In an alloy casing? Given the makers' penchant for making them out of cheese, I'd be very careful about overtorqueing them by 50%.

Iiwy, I'd just torque them to normal and with some Loctite. Anyway, thousands of bike owners have successfully used SS fasteners over the years and haven't had any problems.

While I have great respect for the Roymech site, any tribologist will tell you that you have to be very careful with friction coefficients from sources like this. Personally, what I would do here is to clean out the holes carefully because interference-type loads caused by debris can cause alloy or stainless to "pick-up", then lubricate with a moly grease, then torque to manufacturer's settings. Or use loctite if the manufacturer specifies it (not both!).

After long experience with Rover V-8 engines where many bolts go direct into ally, I always use 3Ms ScotchClad thread sealer. It lubricates, seals, locks and prevents corrosion.

The message from "Dave Plowman (News)" contains these words:

And has a velcro pocket to keep your remote controls in.

Very useful tip, I hadn't come across that product

If you look at a factory W/S manual for things like a P6 it was regarded as essential. You can only buy it in litre tins (about 30 quid) which is enough for about 50 engine rebuilds.

My first tin went solid while still about 3/4 full and 15 years. ;-)

Forgot to say it cures world poverty too.

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Third world excepted.

When I googled I found a rover owners NG posting which suggested it was also available rebadged as a rover spare. I'd be interested if anyone else has a source.

"The four long bolts must be coated with 3M EC776 thread lubricant - Rover part number 605764"