Wheel bearing pre-load

[Bultaco]

My F1 tube frame sidecar with front forks and rear swingarm has angular contact ball bearings with no spacer between them in the front and rear wheels. I have several questions. Should there be a spacer? How is the axle tightened to give the bearings the correct pre-load? Is there any reason this type of bearing is fitted instead of tapered roller bearings as in the chair wheel?

[kew]

Have a look at:
http://www.skf.com/group/products/beari ... index.html
Without seeing the setup that you have and which way the bearings are fitted I'm afraid no one can give you any info.

[666]

These bearings need a spacer between them the same length as the shoulder between them as fitted in your hub. This type of bearing was used in Austin and Morris mini rear hubs.

[Bultaco]

Neither the wets or the drys have spacers fitted. Sidecar is new to me in Canada this year. It was imported from the UK to the USA in 2013. There is a tech sticker on it for Mallory Park Oct 28/12. The only identification found is RCR14 stamped in the upper cross tube at the front of the platform.
Wheels are built up units with machined shoulders at each end for the bearings. Thrust end bears against the shoulder, similar to tapered rollers. I think spacers are needed but as this is new to me I thought there were reasons for this set up that I was not aware of.

[666]

I have run angular contact bearings in all wheels and steering heads since 1965,but thats my preference + I purchased a job lot of these bearings and am still have some left.Taper rollers are also very good,I would make spacers for these as well

[kew]

I agree, whatever the setup you must have a spacer.
I use deep groove ball bearings and a spacer.

[Bill Lymburn]

Not only must angular contact bearings have a spacer but they must have an axial clamping force applied to the spindle to retain the preload, as shown in the SKF sketches...I have had a lot of experience with this set up in machine tools where they perform excellently as they would properly set up in your wheels, however it is a lot of tedious and accurate work to set them up properly.....I would change them to a normal ball or taper roller arrangement, which does not need preload and is much easier to set up....the way your wheels are set up currently is misuse of angular cantact bearings....also if a bearing fails at a meeting, you can change a ball or taper with another, not so your angular contact....that is my opinion....

[kew]

I have also used them in machine tools as Bill says and I have only used them in sets, ie. 2 or 4 together in a pack.
Far less problems with ball bearings.

[Bultaco]

Thanks for all your help. I machined and installed spacers as time is short before the next race. I will remove all bearings over the winter (lots of off season time here!) and will likely fit deep groove or tapered bearings. Preloading angular contact is difficult with this type of set-up. I have deep groove bearings in my vintage sidecar, which uses motorcycle hubs but thought the side load of F1 and F2 sidecars would be too high for them.