BSA Owners' Club Workshop Discussions

The BSA Workshop => Twins => Topic started by: Mike Farmer on 16 Feb, 2019, 16:23

Title: A50 Hydraulic Front Brake
Post by: Mike Farmer on 16 Feb, 2019, 16:23
 :) :) :) :)

I posted on here a "bit back" that I intended to try to put a hydraulic front brake on my A50.
I have now started to get it sorted. I am actually going to use a FWH 19" wheel with a 7" in brake drum. I think it from an A10. That way I wont damage my newly rebuilt wheel.
I intend to use the 7" back plate from a reliant rear axle with all the relevant "guts".
So far it fits together well enough to believe its doable and worth while continuing.
Initial pics tomorrow (with luck)

Mike 8) 8) 8)
Title: Re: A50 Hydraulic Front Brake
Post by: DerekAnderson8 on 16 Feb, 2019, 17:55
sounds good mike, is there room inside for the brake cylinder?

cheers

derek
Title: Re: A50 Hydraulic Front Brake
Post by: Mike Farmer on 17 Feb, 2019, 10:03
 :)

Morning Derek. Yes there is and it seems to have plenty of clearance. Must confess that was a serious concern. If this works then I hope to put an 8" from a Morris Minor in the 'proper' wheel. We'll see!!!!!

Mike
Title: Re: A50 Hydraulic Front Brake
Post by: DerekAnderson8 on 17 Feb, 2019, 11:30
Hi Mike, Has this ever been done before i wonder? it does seem like a good idea, maybe it was too expensive at the time for normal road use.
Title: Re: A50 Hydraulic Front Brake
Post by: Mike Farmer on 17 Feb, 2019, 15:24
 :)
Hi Derek. In answer to your 'Q' I don't know but I seem to recall it being talked about long time ago.

Here are the pics as promised yesterday. I have included the Morris Minor backplate, but I think that I'll try for a rear plate. We'll see-----one step at a time
Title: Re: A50 Hydraulic Front Brake
Post by: Mike Farmer on 17 Feb, 2019, 15:28
 :) :) :)

Follow up to my last. As you see it fits sensibly and looks to some degree like the fit of an M20 front brake plate.
Its going to need a lot of thought and a bit of fairly precise "mechanicing" to make the centre spool ans spindle fitment

Mike 8) 8) 8)
Title: Re: A50 Hydraulic Front Brake
Post by: ChrisG on 17 Feb, 2019, 15:45
Mike,
Great idea and it will no doubt be an improvement on the original. However, the downside is that it does constitute 'substantial change' in that it incorporates parts in a significant area (Brakes) that were not available or fitted by the manufacturer at the time of manufacture, so you will need to have an MOT test each year for it to remain legal.
Let us know if it stalls the rolling road on the test!
Chris
Title: Re: A50 Hydraulic Front Brake
Post by: Mike Farmer on 17 Feb, 2019, 16:09
 :)
Hiya Mr Editor.
I have no problem with annual MOT test. However as the Bike is already on Historic and age related would that still be the case.
If it stalls the rolling road shall I be very surprised or just scared..
With thoughts. The item would have been available but just not on BSA. Further What if I just put a hydraulic actuator on the existing brake set up in place of the cable.????
Mike 8) 8) 8)
Title: Re: A50 Hydraulic Front Brake
Post by: ChrisG on 18 Feb, 2019, 11:16
Hi Mike,
The rules state that vehicles in the Historic class will be exempt from MOT testing provided they have not been subject to Substantial Change which involves chassis, steering, engine, wheels and brakes.
Whilst Hydraulic Brakes were fitted to cars of the period, then yes the components were available but were designed for cars and not fitted to bikes (Certainly not BSA's to my knowledge) as such that would be argued that the change is substantial.
It doesn't affect the Taxation Class but to be totally legal, it will need an annual MOT test.
Reason I was jesting regarding locking up the wheel, is, the components and design that you propose to use would be based on stopping a car with 4 passengers, so maybe a bit over eager with just you and a bike weighing a quarter of that. I locked up the front wheel regularly on a Hinckley Triumph I owned as I couldnt get used to how little effort you needed to operate it. Not funny in the wet though!
Chris
Title: Re: A50 Hydraulic Front Brake
Post by: Richard Mills on 18 Feb, 2019, 13:46
I don't think that a change to a hydraulic system would necessarily invalidate the MOT exemption. The guidance notes state that changes are deemed to be 'acceptable (not substantial)' in certain categories including 'in respect of axles and running gear changes made to improve efficiency, safety or environmental performance'.
Title: Re: A50 Hydraulic Front Brake
Post by: Mike Farmer on 18 Feb, 2019, 16:49
 :)

THanks gents.

I'm paying serious attention to all these points being raised because I certainly don't have sufficient knowledge to dig up all the info. As I said I have no problem with an MOT because if it doesn't pass then I would have serious doubts about being out on the road with it. Most of us are very realistic with regard to this aspect BUT there are a few riding/driving some lethal junk. That is not meant to offend anyone.
Guy the other day took an old Mini in my local tyre man to have tyres done and one of the rear brake pipes was broken--turned over and hammered flat to seal it. No new tyres for him then.

Mike 8) 8) 8) 8)
Title: Re: A50 Hydraulic Front Brake
Post by: ChrisG on 19 Feb, 2019, 17:37
Thanks Richard,
I will look into this as it's a new one on me. Can you tell me where you found the guidance notes as there was no mention of this when this came out last year. However, they are changing their views to suit as time has passed since then.

Mike,
I agree with you and that is a very sensible approach.
Chris
Title: Re: A50 Hydraulic Front Brake
Post by: Richard Mills on 20 Feb, 2019, 15:54
Re MOT exemption, you can find it at (if I can do this link thing!):
https://www.gov.uk/government/publications/historic-classic-vehicles-mot-exemption-criteria/historic-classic-vehicles-mot-exemption-criteria
Title: Re: A50 Hydraulic Front Brake
Post by: DerekAnderson8 on 20 Feb, 2019, 18:12
I have read that advice before and a lot of it only applies to large vehicles, motor cycles are exempt from most of it.

within reason of course.

;)
Title: Re: A50 Hydraulic Front Brake
Post by: Richard Mills on 21 Feb, 2019, 09:31
Once it gets to "Other 'substantial change' criteria (all vehicles)" and then"Acceptable changes" then Section 3 appears to cover motorcycles as well. If not then safety related improvements being allowed for a car but not a motorcycle would be a rather odd provision. Mind you, DVLA/VOSA are rather adept at making odd regulations!
Title: Re: A50 Hydraulic Front Brake
Post by: Mike Farmer on 22 Feb, 2019, 10:41
 :) :)

I too have just read this through and as I see it, it applies to "axles and running gear to improve safety". I would suggest that brakes are part of the running gear.
It also says 'Different rules apply to heavy vehicles'. It does not appear to make any distinction between cars and motorbikes. However my previous about MOTs remains my viewpoint

I'm actually quite surprised that insurance companies are not requiring some sort of safety certification.

Mike 8) 8) 8) 8)
Title: Re: A50 Hydraulic Front Brake
Post by: Mike Farmer on 20 Apr, 2019, 16:46
 :) :)

I have now reached the point where I can "offer up" the brake back plate complete with fitments. I now have two problems.
First. This back plate would have been held in situ with Four bolts on the end of the axle-- That is not possible so I shall need to make approx. the same fitting as a normal Beesa plate.

Second. The Beesa plate is cast and therefore stiff and solid--The one I am using is pressed steel and I'm unsure whether it will 'twist and buckle' under braking stress.

So I may need to make a complete back plate out of something like 4mm plate.. The centre boss as made just has primer at mo.

Take care Mike 8) 8) 8)
Title: Re: A50 Hydraulic Front Brake
Post by: DAVE BRADY on 07 May, 2019, 21:27
I remember way back when there were a lot outfits in the Club brakes were always an issue.  If I remember correctly it was mainly rear brakes that were modified using a Mini brake plate and reliant cylinders.  The Mini plate seemed to be more substantial than the Reliant but the Reliant cylinders were smaller and fitted in the hub better.  I think 1/4" steel plate was used to make up an anchor utilising the lug on the swinging arm.  The brake plate was bolted to this using the existing mounting holes with a spacer welded to the anchor plate to give correct location and clearance in the hub. The brake worked very well with no issues. Unfortunately I do not have any photos.

Dave.