BritBike Forum logo
BritBike SponsorBritBike SponsorBritBike SponsorBritBike SponsorBritBike SponsorBritBike SponsorBritBike SponsorThe Bonneville ShopBritBike Sponsor
Upgrade to: Premium Membership | Premium Life Membership | Vendor Membership | Site Sponsor Membership
ShoutChat Box
Comment Guidelines: Do post respectful and insightful comments.
Buy BritBike staff a coffee
Buy BritBike's staff a coffeeStill here since 1996 serving BritBike enthusiasts..
Search eBay for motorcycle parts in following countries
Australia, Canada, France, Holland, Italy, United Kingdom, USA
Random Gallery photo
Member Spotlight
eightangrybears
eightangrybears
New Hampshire, USA
Posts: 193
Joined: December 2010
Show All Member Profiles 
Newest Members
Digital Expressions, johnjorgensen, Ray Byrne, Heff, kerna
10915 Registered Users
Top Posters(30 Days)
franko 77
quinten 65
Popular Topics(Views)
1,050,963 mail-order LSR
a word from..
Forum Statistics
Forums34
Topics68,068
Posts683,226
Members10,915
Most Online14,755
May 5th, 2019
Who's Online Now
59 registered members (Beach), 348 guests, and 931 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 2 of 2 1 2
Re: Front brake suggestions requested [Re: David Dunfey] #786141 10/03/19 11:02 am
Joined: Nov 2004
Posts: 17
Chip205 Offline OP
BritBike Forum member
OP Offline
BritBike Forum member
Joined: Nov 2004
Posts: 17
Originally Posted by David Dunfey
John,

I think that Chip was saying that he chose the wrong lining application,



Just so. Or perhaps I didn't know enough at the time to request what I wanted. I've little experience with drum brakes on street bikes. All I ever did, on cars and bikes, was mount new shoes -- and I've never had a street bike with a front drum after my first bike, a Yamaha DT1 250 (48 yrs riding and counting). Back then, when I had those vehicles, new shoes were readily available. The only time I ever had shoes relined was on my Bultaco and Montesa trials bikes ('70's). And then a friend swore Model T linings worked better than stock. He was right.

Last edited by Chip205; 10/03/19 11:05 am.

Chip205. '61 Clubman's Gold Star, '13 Daytona 675 R, '13 Duke 690, '18 Street Triple 765 RS, '20 R1250R
Support Your #1 BritBike Forum!

Check out British motorcycles for sale:
British Motorcycles on e-Bay UK
British motorcycles on e-Bay North America
Re: Front brake suggestions requested [Re: Chip205] #786144 10/03/19 11:50 am
Joined: Nov 2004
Posts: 17
Chip205 Offline OP
BritBike Forum member
OP Offline
BritBike Forum member
Joined: Nov 2004
Posts: 17
Ummm...(sheepish look)...except for the Gold Star which I rode a fair bit in the '70's. I remember the front brake being fine.


Chip205. '61 Clubman's Gold Star, '13 Daytona 675 R, '13 Duke 690, '18 Street Triple 765 RS, '20 R1250R
Re: Front brake suggestions requested [Re: Chip205] #789066 11/03/19 8:44 pm
Joined: Nov 2013
Posts: 41
J
JonnyD Offline
BritBike Forum member
Offline
BritBike Forum member
J
Joined: Nov 2013
Posts: 41
Hi, I have an RGS with the 190mm brake. When I went through this bike in 2012 I ground the shoes on a jig I made which held the shoes set at a controlled diameter. Following some advice I found on the internet I ground them to be .005" smaller then the drum. Ever since this brake has been about the best bike drum brake I have ever experienced (more than matching a an 8 inch BSA 1/2 width brake with old Ferodo green linings). Two fingers can lock the wheel if you wish. Being 1LS it is not grabby and holds the bike well on uphill T junctions. The shoes on this brake are very wide and I feel that grinding or careful turning of the shoes really does matter. I have ground or turned quite a few sets of lining on British brakes and providing its done so that there are not untoward stresses on the brakeplate when doing it, it reliably makes a good brake. The jig has a threaded rod that you can adjust to pull the brake on. The jig also matches the ID of the brake plate hole closely and mounts between centres so you can take the assembly out partway through if you feel the need. You do need to be able to set the diameter fairly accurately - I use a 12 inch digital caliper. Grinding is the best way to remove lining material but a SHARP EDGED carbide tool can also work well (HSS does not last well). Before starting I cover the lathe chuck with a close fitting polythene bag and use dampened newspaper to cover the bedways and use fairly light passes. I generally believe that BSA knew how to make good things and if you fettle what they provided, you can usually get better results than you might expect. HTH,
Jon

Last edited by JonnyD; 11/03/19 8:47 pm. Reason: typos
Re: Front brake suggestions requested [Re: Chip205] #789068 11/03/19 9:16 pm
Joined: Aug 2015
Posts: 1,460
A
Andy Higham Offline
BritBike Forum member
Offline
BritBike Forum member
A
Joined: Aug 2015
Posts: 1,460
I fitted a Robinson replica 4LS It is very powerful but controllable too, I bought it from JL in Czech Republic https://www.jl-exhausts.com/robinson-230mm-4ls-front-brake-1999-p.asp
[Linked Image from live.staticflickr.com]20170908_145323 by Sigma Projects, on Flickr


BSA B31 500 "Stargazer"
Greeves 200 "Blue Meanie"
Greeves 350
Greeves 360
Suzuki GSX1100 EFE "Sorcerers Apprentice"
GM500 sprint/LSR bike "Deofol"
Jawa 500 "Llareggub"
Aprilia RSV Mille "Lo Stregone"
'35 & '36 OK Supreme
Kawasaki ZZR1400 "Kuro no senshi"
Re: Front brake suggestions requested [Re: Chip205] #789069 11/03/19 9:18 pm
Joined: Aug 2015
Posts: 1,460
A
Andy Higham Offline
BritBike Forum member
Offline
BritBike Forum member
A
Joined: Aug 2015
Posts: 1,460


BSA B31 500 "Stargazer"
Greeves 200 "Blue Meanie"
Greeves 350
Greeves 360
Suzuki GSX1100 EFE "Sorcerers Apprentice"
GM500 sprint/LSR bike "Deofol"
Jawa 500 "Llareggub"
Aprilia RSV Mille "Lo Stregone"
'35 & '36 OK Supreme
Kawasaki ZZR1400 "Kuro no senshi"
Re: Front brake suggestions requested [Re: Chip205] #789533 11/08/19 8:47 pm
Joined: Dec 2011
Posts: 308
D
DBDBrian Offline
BritBike Forum member
Offline
BritBike Forum member
D
Joined: Dec 2011
Posts: 308
This was my solution to improving the stopping department, It works very well, but the down side being it is quite heavy. I did weigh it at the time, but didn't record the figure.
It probably weigh more than Andy's Robinson. That's a nice looking bike.



[Linked Image from i.postimg.cc]

[Linked Image from i.postimg.cc]


Brian

Made In England
Re: Front brake suggestions requested [Re: Chip205] #789564 11/09/19 6:23 am
Joined: Feb 2012
Posts: 1,324
Kerry W Offline
BritBike Forum member
Offline
BritBike Forum member
Joined: Feb 2012
Posts: 1,324
I've admired DBDBrian's doubled-up brake before, in the flesh - at East Kirkby, I think, for the Wolds Run. Some attention to detail there - notably the mirroring of the back plate, with the drain hole repositioned, etc.

He must think it works ok - given the fitting of the security bolt!


No generalisation is wholly true, not even this one.
Oliver Wendell Holmes
Re: Front brake suggestions requested [Re: Chip205] #789619 11/09/19 8:18 pm
Joined: Aug 2015
Posts: 1,460
A
Andy Higham Offline
BritBike Forum member
Offline
BritBike Forum member
A
Joined: Aug 2015
Posts: 1,460
Wheelies shouldn't be an issue with that set up :-)


BSA B31 500 "Stargazer"
Greeves 200 "Blue Meanie"
Greeves 350
Greeves 360
Suzuki GSX1100 EFE "Sorcerers Apprentice"
GM500 sprint/LSR bike "Deofol"
Jawa 500 "Llareggub"
Aprilia RSV Mille "Lo Stregone"
'35 & '36 OK Supreme
Kawasaki ZZR1400 "Kuro no senshi"
Re: Front brake suggestions requested [Re: Chip205] #789636 11/09/19 10:57 pm
Joined: Dec 2011
Posts: 308
D
DBDBrian Offline
BritBike Forum member
Offline
BritBike Forum member
D
Joined: Dec 2011
Posts: 308
Yes Kerry, our paths did cross at the Wolds run, but unfortunately we did not meet, lets hope some time in the future.
I fitted two security bolts, as the holes were in the rim. I was glad I also have two in the rear wheel , as it deflated a bit sharpish last summer when I picked up this through the tyre.

[Linked Image from i.postimg.cc]


Andy, I don't think Clubmans Goldie's were renowned wheelies, unfortunately I think I maybe well past trying. 😊


Brian

Made In England
Re: Front brake suggestions requested [Re: Chip205] #789727 11/10/19 8:20 pm
Joined: Sep 2004
Posts: 1,124
gunner Offline
BritBike Forum member
Offline
BritBike Forum member
Joined: Sep 2004
Posts: 1,124
That's a great mod Brian, and I'm left wondering how you managed to join the two hubs together? I guess the original left hand small spoke spool would have been turned off with a lathe and then the two brake drums were carefully welded together ensuring they were Concentric. I was also wondering if there is any issue with the left hand drum being more efficient than the original right hand drum given that the left lever orientation is now different?

Based on the original question on front drum brakes and how to improve them here are my thoughts:-
- what's has not been mentioned so far is the type of cable used and its routing. I've recently started using Venhill brake cables which have a Teflon inner lining and have noticed a marked improvement in brake performance. I believe the Teflon lining reduces frictional loss when the handlebar lever is pulled and therefore increases the pull on the brake drum lever. Additionally its important to check that the cable has no sharp curves or bends as these also cause frictional losses.
- another thing to check is the handlebar brake lever pivot length, this is then length measured between the lever pivot and brake cable nipple. Many levers have a pivot length of 1-1/16 inch and a improvement can be found by using a lever which uses 7/8 inch pivot as the mechanical advantage is greater.

I've recently made the above changes to my B44 front brake which uses an 8 inch SLS brake with floating shoes. The front brake is now much better than previous and it almost feels like the front wheel could lock up in an emergency braking situation, certainly much better than before.


1968 A65 Firebird
1967 B44 Shooting Star
1972 Norton Commando
Re: Front brake suggestions requested [Re: Chip205] #789737 11/10/19 9:38 pm
Joined: Aug 2015
Posts: 1,460
A
Andy Higham Offline
BritBike Forum member
Offline
BritBike Forum member
A
Joined: Aug 2015
Posts: 1,460
A trick I have seen for vintage racing where the rules prevent external linkages on the brake.
An abutment for the trailing shoe is fitted next to the cam and the existing abutment is removed and a floating one installed. This effectively makes both shoes into a long leading shoe with a hinge in the middle


BSA B31 500 "Stargazer"
Greeves 200 "Blue Meanie"
Greeves 350
Greeves 360
Suzuki GSX1100 EFE "Sorcerers Apprentice"
GM500 sprint/LSR bike "Deofol"
Jawa 500 "Llareggub"
Aprilia RSV Mille "Lo Stregone"
'35 & '36 OK Supreme
Kawasaki ZZR1400 "Kuro no senshi"
Re: Front brake suggestions requested [Re: Chip205] #789833 11/11/19 6:25 pm
Joined: Dec 2011
Posts: 308
D
DBDBrian Offline
BritBike Forum member
Offline
BritBike Forum member
D
Joined: Dec 2011
Posts: 308
Thanks Gunner, In answer to your question, the original spoke flange is pressed into the drum, I made a centre shouldered sleeve, which carries both drums.
[Linked Image from i.postimg.cc]

I have attached a couple of mock up drawings of the hub / spindle arrangement.
[Linked Image from i.postimg.cc]

[Linked Image from i.postimg.cc]


Re the L/H lever / cam operation, the effect is the same, as the drum is rotating anti-clock viewed from the plate.

I have considered TLS plates, which a mate will CNC machine from billets. The drawing / programme for the plates still needs a little tweaking before making a start, but other commitments keep getting in the way, and then of course there is the extra weight to consider.

[Linked Image from i.postimg.cc]
Front face

[Linked Image from i.postimg.cc]up images
Rear face
This is the R/H plate, the programme only need reversing for the L/H version


[Linked Image from i.postimg.cc]upload a photo and get url

I have two billets ready




Yes, good cables and there alignment play a big part in brake performance, the gold star clip-ons use the short 7/8" pivot levers.


Brian

Made In England
Re: Front brake suggestions requested [Re: Chip205] #789894 11/12/19 3:54 am
Joined: Sep 2004
Posts: 1,124
gunner Offline
BritBike Forum member
Offline
BritBike Forum member
Joined: Sep 2004
Posts: 1,124
Quote
An abutment for the trailing shoe is fitted next to the cam and the existing abutment is removed and a floating one installed.


Yes I've heard about this mod which I believe is called the Bendix Duo-Servo self-energizing concept, a description of this mod can be found in the Victory Library at This Link near the end of the page. Looks like the cam has to be ground so that only the lower lobe is present and the pivot bolt removed so the shoes can float freely. Seems like a good idea and worth a try.

Thanks Brian I didn't know the smaller spool was pressed on using a sleeve, so joining the two drums together using a new sleeve would be relatively easy. Presumably the position of the new drum relative to the rim had to be considered so that the spokes would fit.


1968 A65 Firebird
1967 B44 Shooting Star
1972 Norton Commando
Page 2 of 2 1 2

Moderated by  Rich B 

Home | Sponsors | Newsletter | Regalia | Calendar | Bike Project | BritBike Museum | Spiders Cartoons | DVD- Manuals & Parts books
Upgrade to: Premium Membership | Premium Life Membership | Vendor Membership | Site Sponsor Membership
Powered by UBB.threads™ PHP Forum Software 7.7.3