• Welcome to the website of the Vincent H.R.D. Owners Club.

    Should you have any questions relating to the Vincent H.R.D. Owners Club, or Vincent H.R.D. motorcycles in general, please contact Graham Smith, Hon. Editor and Webmaster by calling 07977 001 025 or please CLICK HERE.

    You are unrecognised, and therefore, only have VERY restricted access to the many features of this website.

    If you have previously registered to use this forum, you should log in now. CLICK HERE.

    If you have never registered to use this website before, please CLICK HERE.

FF: Forks Brampton Steering Stops


oexing

Well Known and Active Website User
VOC Member
In my setup above I have used a plastic bush for bearing, 12 mm high, the original size more or less I believe. The head lug was machined for old BMW taper roller bearings 34-51-12 mm . The lower Brampton casting just 1 mm clear of the head lug, you cannot go higher so all depends on variations in castings where parts hit their stops. Anyway I like to have defined faces for stops and not slopes for big variations of stops from tolerances. In case the Brampton sits lower you get even poorer stops. So my consequence was welding - which is not critical on the stop extensions even with cast iron. Real cast iron is welded with nickel rods basically that you can use anywhere when in doubt about brittleness. The welded stops should keep up in normal use , for tank slappers on Bramptons no argument, no ? Even so , I will fit hydraulic steering dampers to the Brampton, less so due to tank slapper anxiety but for smooth driving on bikers´roads, one handed on rough roads no troubles then. I found the hydraulic damper on the tele Horex great on rough three dimensional roads where there was some judder in the handlebar with friction damper only.

Vic
 

Cyborg

Well Known and Active Website User
VOC Member
If you or someone else has a new bearing (as in new and not NOS) that they are willing to measure, I may have an original one or two because I seldom throw out anything that is metal and round. Just have to find them.
Recently I was checking out two sets of lower bearings and both had cracks. Is it possible that later bearings had more beef in that area to reduce cracking? Who knows... it’s a long shot, but there has to be some sort of explanation for the difference.
 
Last edited by a moderator:

oexing

Well Known and Active Website User
VOC Member
You mean broken races from ball bearing types ? These should be strong enough for not braking ? Maybe knocked out from the head lug by brute force ? My photos in first page were made with 12mm bearing height and the lower Brampton part just clearing the head lug by 1 mm, you cannot go higher a lot. So any bearing with more than 12 mm (1/2") will make things even worse. So when not having some welding you´d have to come up with a different steering stop idea.
The BMW replacement taper roller in the Ebay link may come as a great alternative in case the head lug sizes are fu***d up or questionable. Sizes are 34 - 51- 12 mm . But this is an "interesting" machining job to get perfect alignment and parallel seats for slim size bearings.

Vic
Taper roller bearing
 

Cyborg

Well Known and Active Website User
VOC Member
Yes ball type. Not sure why they were cracked. I found the cracks when they were still installed in the UFM. Just inspecting them to see if they were reusable. Not knowing there history, I suppose they could have been cracked during installation which was at least some 50 years ago and they may be original. Once they are safely home in the steering head, I don’t see a reason why they should crack. Seemed odd that I had two different lower bearings with the same cracking.

Edit... just went and looked at one of the bearings. It’s the inner race that is cracked, so still quite possible it was cracked when installed or too much interference fit on the stem?
 
Last edited:

Robert Watson

Well Known and Active Website User
VOC Member
Cyborg ---- Maybe we should get together and see if any of your cracked races line up with mine and we could make up some pairs - Oh just a minute!!!!
 

greg brillus

Well Known and Active Website User
VOC Member
If the bearing is too tight a fit on the lower stem they will crack, pays to check them and give not more than a thou interference any more is risky.
 

Cyborg

Well Known and Active Website User
VOC Member
If the bearing is too tight a fit on the lower stem they will crack, pays to check them and give not more than a thou interference any more is risky.
Good plan. This stem is scheduled for service so when I get the new bearings it’ll be out with the micrometers.
 

ogrilp400

Well Known and Active Website User
VOC Member
Can we get back on track now guys. Something is amiss here and it would not have been like this for the past 70 years and surely I'm not the only one that has had this problem. (famous last words). I have now encountered another problem with these Bramptons. Read the next thread.
 

Robert Watson

Well Known and Active Website User
VOC Member
It been clearly established that I’m a little different.... so what’s your excuse for hanging onto cracked bearing races. #yardartbin
Much more of a braggart bin labelled "Shit I have destroyed on my Vincent" which is on the shelf next to a box of string labelled "Pieces of string too short to keep"

The first one has smashed double gears, bent lay shafts broken followers, destroyed pistons, trashed big ends, eviscerated clutch sprocket, and even its smaller mate. A whole lot of heartache in there, not to mention cubic $$$$

The string box by comparison has, well, string!

So there, thread suitable diverted, but when in self imposed lock down what else can I do??????
 

vin998

Well Known and Active Website User
VOC Member
VOC Forum Moderator
Greg has pointed out an important note in posting #12 of the other Brampton discussion:

Here is what Greg wrote in itialics:

"Looking at your steering stops, the travel is too much, this is what Ken was asking about in his first post about the steering stem being too low to contact the stops on the head lug correctly. I think it is common problem perhaps an over look by the factory, as I have had the same issues with bikes I have done, including replacement forks assemblies in the last couple of years. leaving out the FF 36 washer (if one is present) can help out a little here."


FF36 washer was never fitted on the Bramptons (Series A & B) and looking in the Vincent parts book this washer and the felt seal is not listed or shown in the diagram MO30 either. I have checked my early B copy and later B/C copy and both agree.
If you fit FF36 to Bramptons it wll drop the lower yoke the thickness of the washer and so exagerate the problems with the steering stops contact area. I guess originally there was no way of stopping water etc getting into the lower bearing, or from keeping the grease in the bearing which is why Vincent added the felt washer and FF36 when they designed the Girdraulics.

Simon
 

greg brillus

Well Known and Active Website User
VOC Member
Because the Brampton's like many other items produced outside the factory could be a compromise........Is the lower stem assembly a common part that was used on forks to suit other makes of bike perhaps. The fact that the main rib on the lower stem seems to miss the factory "Stops" on the headlug may not have been a major concern for the factory so long as the bars and fork components didn't hit the tank. The cramped set up of the handlebars can be an issue with the best of these bikes, especially when extra electrical switches and so on are used. It is one of those little mysteries we may never know the answer to.
 

Top