better brake

[ken-drink]

i have a 1954 fielmaster 500 twin, the front brake is poor even though it has been relined with a softer material and is better than it was, has anyone fitted something like the BSA 8 inch half width hub as used on things like goldstars etc, good brake and works well, i know it will need the forks changing , but not sure on the spacing or if the bsa forks will fit into the ariel fork yokes, any info would be appreciated.
Ken

[will_curry]

I put BSA fork bottoms on Ariel fork legs - they're pretty much the same anyway -
but the Ariel legs are wider apart so the rim needed offsetting and a longer
spindle making. i think there is an issue fitting BSA yokes to Ariel frames
but I can't remember what until I find my notes.

[Simon.Gardiner]

The rim doesn't need offsetting if you use the right spacer on the brake side.
I've seen it done using an Ariel spindle with a short hex extension welded to the non-brake side end ('cos the spindle goes into the Ariel fork leg just further enough to make it difficult to get a tommy-bar into the hole).
NB Not judging how how good that solution is, just saying I've seen it done that way - it was on a Huntmaster combo and I don't recall there ever being any problems with it!

SG

[will_curry]

The steering stems are different lengths and this is where the
problems come:

The Ariel headstock is 7" long and the steering column is 6 7/8" from bottom yoke
to bottom of the adjustment threads.

The BSA headstock is 6 1/4" long and the corresponding steering column length
is 6 3/8".

The BSA parts I measured are from a pre-unit single. I'm pretty sure the pre-unit
twins are the same. I don't know about the unit bikes - too modern.

It's worth knowing that while the ID and OD of Ariel and BSA headset bearings are
the same the depth isn't, the BSA being thicker if memory serves me well. Somebody
produced some bearings some time ago which were an intermediate and were supposed
to fit both BSA and Ariel but didn't.

[charles.bulloch]

Fitting a 8" finned BSA brake to a 54 Ariel.

You can get ACME stainless to make you a new spindle the same overall length but approx 1/4 inch longer for the thinner section. I sent Clay the wrong sizes and resorted to filing off the original spindle. You need a spacer to fill the space between the spindle and brake plate, Clay made mine, I sent the correct dimensions for a change.

spacer to sit in the brake back plate


outside diameter 0.8 inches

inside diameter 0.625 inches

length 0.8215 inches. This had to be filed a little.

You fit the same bearings as the Ariel to the hub. The brake side bearing needs a top hat thing that the spindle butts up against.

https://draganfly.co.uk/shop/65109/bear ... d/#4040-47

I fit a strut between the right hand mudguard mount studs and the brake plate as a stay. I have seen a really neat arrangement using the standard clamp on the fork mounting to the fulcrum/adjuster pin.

Charlie

[ken-drink]

thanks guys all useful info, seems it is possible to do, now to go on the hunt for the right bits.
Ken

[Dave.Barkshire]

If you want a really good brake some members have converted their post war front stoppers to hydraulic.

http://forum.arielownersmcc.com/viewt ... 84&p=26011

[ken-drink]

that looks a good idea, but needs some machining which i dont have the ability to do, so the BSA 8 inch half width hub with a twin leading shoe brake plate will do the job.
just got to go hunting for the bits now
Ken

[Simon.Gardiner]

You can find a twin-leader plate for an 8" BSA drum? I couldn't - where do they come from?
Anyway, I've now got the twin leading shoe 8" (almost!) front wheel from an R50 and/or R60 airhead BM waiting to go in. I'm not the first person to do this - might even be easier than putting in the BSA wheel.

SG

[will_curry]

I'd wondered if the fork legs from an A65 could be made to fit the Ariel yokes
without too much fettling. Then there are plenty of 2LS brakes and
wheels available. I'm going to our A65 specialists on Friday. I'll take
an Ariel stanchion and a box of teabags . . .

I'm sure there are images of the BMW brake in an Ariel setting on this
forum somewhere. It looked quite in keeping.