H: Hubs, Wheels and Tyres Poor brakes, 1948 HRD rapide.

[Eric]

I'm not sure where you get your information from Eric but this is simply not true! Taper roller bearing are more often fitted with pre-load, particularly in high radial load situations.

Taper roller wheel bearings get hot, clearance needed when set cold.
Vincent manuals, mention 1/32" play at wheel rim.
When shimming, the wheel bearings.
Read, any vehicle repair manual, on setting the wheel bearings.

Eric.

 

[Eric]

Aren't Velo mains fitted with a bit of nip, in a fiddley process?

Yes, they have to shimmed, with Zero play.

 

[Simon Dinsdale]

Aren't Velo mains fitted with a bit of nip, in a fiddley process?

Velo mains are 4 thou preload when assembling cold. The theory is that when the engine heats up and the crankcases expand the preload disappears. Well thats the theory anyway.

 

[BigEd]

I'm not sure where you get your information from Eric but this is simply not true! Taper roller bearing are more often fitted with pre-load, particularly in high radial load situations.

Dear Eric,
Your statement about bearings is somewhat short of the mark. All types of bearings need some play or they would not turn. Taper roller bearing in general have great load capacity and durability. (Lots of Vincent/HRD machines still running around on there original taper roller wheel bearings.) Sealed journal bearings are usually and quick and easy to fit for the motorcycle producer. They don't however have adjustment and have to be replaced when they develop play. I certainly have had to replace sealed journal wheel bearings on my more modern bikes to get them through an MOT.
Not getting at you but just to point out that it is easy to make a generalisation that people take as gospel because they have seen it in print.

 

[Eric]

Dear Eric,
Your statement about bearings is somewhat short of the mark. All types of bearings need some play or they would not turn. Taper roller bearing in general have great load capacity and durability. (Lots of Vincent/HRD machines still running around on there original taper roller wheel bearings.) Sealed journal bearings are usually and quick and easy to fit for the motorcycle producer. They don't however have adjustment and have to be replaced when they develop play. I certainly have had to replace sealed journal wheel bearings on my more modern bikes to get them through an MOT.
Not getting at you but just to point out that it is easy to make a generalisation that people take as gospel because they have seen it in print.

Hi,
Your quite correct.all bearings do have play, its the amount of play.
Which is why it pays, to by good quality branded bearings.

 

[vibrac]

And it is written
"when cold there should be .005 in end float on the hollow axel relative to the hub body, noticeable by approximately 1/32 in shake at the rim"
Thus spoke Paul Richardson
I know before I found a true engineer to do my MOT's I had a big argument with a young slip in greasy overalls who had no idea what a taper roller bearing was and was certain the shake was a bearing going - the same guy who tried to tell me the headlamp of my BMW R90 was shining too high - "No" I said "you need to sit on it to test it, not leave it on the centre stand"

 

[greg brillus]

I kind of recon Eric is on top of his brake issue...............crankshaft end float and MOT's...........????

 

[Bill Cannon]

I've seen several mentions of airhead BMW taper wheel bearings. As a BMW dealer I have fitted many of these and can assure you all that the correct procedure is to shim the bearings until the correct preload is achieved. This is measured by rotating the wheel with a special torque device that reads very small torque settings. I can't remember the actual figure, it's been many years since I've done one!
Bill

 

[vibrac]

I've seen several mentions of airhead BMW taper wheel bearings. As a BMW dealer I have fitted many of these and can assure you all that the correct procedure is to shim the bearings until the correct preload is achieved. This is measured by rotating the wheel with a special torque device that reads very small torque settings. I can't remember the actual figure, it's been many years since I've done one!
Bill

Wish you were here Bill! I have been putting off renewing the rear wheel bearings on my BMW Difazio project. When the hub is worn it looks like a real nasty of a job to insert the RH taper cup down inside the tunnel after heating the hub. I have the bearings an infra red temp gun some special locktite to wick up the sides and a tool to insert the gubbins but I am very loath to do it -very out of character!
let alone sorting the preload though I have read about Heath Robinson arrangements of string and spring balances and stuff
No doubt about it, the Phils had it sorted years before

 

[stu spalding]

I've seen several mentions of airhead BMW taper wheel bearings. As a BMW dealer I have fitted many of these and can assure you all that the correct procedure is to shim the bearings until the correct preload is achieved. This is measured by rotating the wheel with a special torque device that reads very small torque settings. I can't remember the actual figure, it's been many years since I've done one!
Bill

Hi Bill, does the BMW have a steel axle in an aluminium hub? Stu.