H: Hubs, Wheels and Tyres Are These Standard or Racing Drum Brakes?

[Chris Launders]

That looks to be magnesium to me as alloy would normally be shiny silver where the felt seals rub whereas yours are grey, but they look to be in absolutely 1st class condition, see what others say.

 

[timetraveller]

From memory the early aluminium ones were not very well made and had the air scoops cast in. Possibly not all were like that but the ones you show have separate air scoops and look like the original electron ones. If you are prepared to remove a very small piece from somewhere it will not be noticed you can try to set fire to the small piece, somewhere safe. Magnesium burns with a very bright flame. Be careful.

 

[litnman]

When were the hub, spoke plates and brake drums first finished with 10 bolt holes?

 

[Marcus Bowden]

Commit old electron plates only on static machines (not used). I have a pair but bought an aluminium set to fit to a Lightningised Rapide I'm doing, you will soon tell if they are magnesium by taking one off removing the shoes and the plate will feel lighter than the shoes and they are definitely electron if there are bushes in the cam shaft holes. My French friend Herve' le' Manach had a "D" Rapide and he had one on his single rear brake (as that was all "D's" had) we were in the Pirranees going to the FIM rally in Barcelona 1989 lot of corners and his brake plate failed (shattered) we pulled over and wife & I on a "B" Rapide and Dick Powell on a 350cc AJS.
Whilst on the road side I removed my gear wheel and a Brake plate to put on his "D" single brake, Herve' now had a rear brake and I didn't notice the difference. Whilst doing this road side repair we hears Vincents approaching and it was Norman Lord with son Alister on the back and an older son riding another Rapide,, Christine gave them cups of tea as she brewed up whilst stopped then we all carried on together. If you want a set of steel plate I will give you some, I still use them and my brakes are good and firm there is one mod I'd like to do on them and that is to skim the drums whilst running on their bearings weight of aluminium asa posed to steel is negligible and just as solid with gussets fitted. PM me.
bananaman.

 

[timetraveller]

Ten holes in Shadows, five holes in Raps and Comets as far as I know. Not a date thing.

 

[litnman]

Ten holes in Shadows, five holes in Raps and Comets as far as I know. Not a date thing.

H2/2 and H34/8 were numbered as "Racing" with 10 holes.

 

[LoneStar]

If you don't want to light shavings on fire to identify the material, you could determine their density. Strip to the bare plate, submerge in water to find volume, and weigh. Aluminum is about 2.7 g/cc, magnesium 1.7.

 

[vibrac]

Those casting marks are not from Slater I would hazard

 

[davidd]

The useful life of Elektron was about six years from new. The Flash had a single rear brake when raced in the 1960s, and both original rear plates failed under heavy braking. First one, then the other. A stock steel backing plate was used instead.

John Renwick used an Elektron plate and a Rapide drum on the rear of his Comet Racer. The Rapide drum shattered during practice at Daytona and I ordered a Shadow drum from Coventry with overnight delivery. It showed up in time for the race. I made a rule for myself to use only new brakes and hubs on any racing machine I built. On the Comet racers, I use only five of the ten bolts, but I use higher than grade 8 bolts and nuts with no problems.

Aluminum replicas have worked well.

David

 

[Eddie Foreman]

Bit of an update - the Electron plates have been removed. Had a rummage around the garage and found some old steel plates which are away to be vapour blasted and powder coated. Along with the steel plates I found these cast plates. Any ideas on who might have made them?