Spring Claws SP1/1

[Tom Gaynor]

The "anti-cocking" design was, I am sure a Reg Bolton mod to his racer in Japan, detailed in MPH, and it worked. Assuming that the spring covers do not overlap 100% on compression, longer inners or outers would seem a better way of doing it. Since I don't believe this has been suggested or tried perhaps there is some reason it can't be done? Dunno.
The "slim studs" will work fine if the coil-over unit fills most of the gap in the RFM. : the stud is mainly in shear with the standard set up, and the loads relatively trivial. It'll take 4 tons to shear (assuming 3/8" studs in 36 ton steel) in single shear, and it's in double shear so you'll need twice that. More germane is that the coil-over units are already in use, and no hint of a problem has surfaced.

I purchased a complete set of Thornton rear springs before the spring over dampers became available, so I sort of feel compelled at sometime to give them a try, with regard to cocking, if the spindles are nice and free to oscillate in their bushes with the movement of the spring box eye bolts how bad is the cocking and is it further increased by the fact that that the springs are smaller in diameter than the original springs. I note in the kit that I purchased there are supplied a couple of small angle iron brackets with self adhesive velcro strips to overcome the problem but with best will in the world I simply cannot see how this could be strong enough to work. I did consider getting made by my friendly metal fabricator some reduced diameter spring boxes with the added advantage that it might enable me to get one of the very slightly taller black Westco batteries of more less the correct dimensions in place of the original battery, but is really worth all the bother, I have been using Petterford sidecar springs fully sprung with a Koni since time begun, but when I read about John Emanuel's silky suspension I does make one wonder what I am are missing out on. Is anyone out there using the new coil over device and if so does it fit in the center and if so are relatively slim studs up to job when I guess with the original set up the stress the springs inflict on the stud was supported right next to the UFM and the rear frame. Questions, Questions

 

[bmetcalf]

Justin MacKay-Smith in Virginia made a few set of longer spring cans, I believe. David D. would know for sure.

 

[b'knighted]

Marcus Bowden's very modified B has no external spring boxes, using instead, a telescopic central shaft to hold the claw eyebolts in line. If this is all that is needed to keep the ends from cocking, a similar device could be hidden inside a more standard looking set up to prevent scuffing.

Cheers

 

[bmetcalf]

The details of that would be interesting to see. Does Marcus visit these hallowed pages?

 

[Peter Holmes]

Well I think Marcus does visit this site but I think I will be safe in attempting to give at least a brief description, this is from memory as I last saw Marcus about a year ago and we discussed this modification. The top claw is bored out and threaded with a larger diameter fine thread, maybe the bottom one also, not sure , then you make a largish bar with a thread at the top to match the new top claw thread and either thread the top to take the eyebolt or manufacture as one piece, drill a hole up the other end of the rod to receive the bottom rod made to a clearance diameter and then the two rods slide one inside the other telescope fashion down the centre of the spring, also you can play around with preload and ride height in situ. The only problem that I can see is that of wear where one rod constantly moves piston fashion inside the larger diameter bored rod, I remember seeing a prototype where the female top rod had ovalled a little, I would guess it would need constant lubrication. In any event it looks great and it seems to work really well. might be worth sending a PM to Marcus for more info, I might have it all wrong

 

[vibrac]

You could always do what we have done to the Comet racer :fit Marcus Bowden standard spring attachments, then there are no outer covers to worry about and its less weight

 

[Joshua Mackay-Smith]

Justin MacKay-Smith in Virginia made a few set of longer spring cans, I believe. David D. would know for sure.

He did (he also had springs made to go in them), but had no interest in setting up in the parts-making business, so it's unlikely he'd make another set.

jdms

 

[Albervin]

Maybe all these clever people (absolutely no sarcasm here only envy) could submit their ideas/inventions/modifications to MPH with the proviso that there is no liability etc. etc.... The specs and pictures of my own coil over damper mod on my B has been sent to whoever wants to see it on the basis that it works for me but you make your own choice.