I'm determined to do this. The Ural has a 20mm axle. I've got the Lester wheel, and I've got the bearings in the Lester with 20mm ID. But there's a lot more to the assembly.
Has anyone done this?
There should be 'dust covers/grease seals', a way to stabilize the bearings along the axle plane ('top hats'?), and a way to keep a constant tension on the bearings regardless of load.
All I have at the moment is the Ural castellated nut, a Ural dust cover.
Lonnie, somehow I think you've tried this.
I've used Harley wheels on several Urals with 3/4" axles.
Lonnie
When you remove the brake backing plate from the Ural axle you will see that the axle is larger in diameter in this area and not machined. You will need a spacer to space the wheel out such that the wheel bearings will be on the machined 20mm section of the axle. You will also more then likely need to cut off the stud from the swing arm used to keep the brake backing plate from spinning. You may also need a spacer on the out side of the wheel in order to center the wheel and get the retaining nut on the axle. Or depending on the Lester you are using you may find you need a longer axle which is another post altogether. If running a brake (I always recommend a brake for safety, I can see little reason why a person would not want a brake) a disk brake is easier to do. You will want to run the smallest diameter brake rotor you can fit to the wheel and use a small single piston caliper. You will then need to weld down a caliper mount to the swing arm. (we can supply the caliper and the mounting plate) You may still find that the brake is to strong in which case you will need to reduce the pressure to it with a proportioning valve.
Jay G
DMC sidecars
www.dmcsidecars.com
866-638-1793
Thanks Jay and Lonnie.
Lonnie: 3/4" 19mm. Pretty close, but the bike pulling the chair is a '78 airhead. The Lester wheel is to match (and only for appearance sake) the wheels on the bike.
Jay: What would you say to the idea to replace the Ural Axle with a machined 14mm axle that would fit the Lester/BMW wheel bearing pack. True? Any disadvantages to this approach?
Your BMW wheel has either a 15mm 17mm or a 20mm axle, Not a 14. If it has a 15mm axle there is a bearing that has the same O.D. as your current bearings but has a 20mm I.D. All you need do is switch the bearings and make a new sleeve for between the bearings. I do not like the idea at all of going to a smaller axle but if you have to you could go to a 17mm axle, no smaller.
Also make sure your sidecar was mounted with proper sub frames, the air head has a very weak frame. BTW, I ran an 1978 R100/7 with a Ural on it for a few years, at the same time my wife had an R100S with a Sputnik.
Jay G
DMC sidecars
I got to thinking about this more, Your BMW should have 17mm axle on this BMW.
Jay G
DMC sidecars
