Britbike forum Forums British Motorcycle specific Brands Bsa bulletin board OIF front end on a dry frame A65 (again)

I know, this is my second thread on this topic. From the last thread, I determined that, as far as steering head issues go, it's a possibility, at least worthy of further investigation.

Now about the wheel: I had abandoned the whole idea because I thought I would have to use an OIF wheel, and the only one I have is very rusty. HOWEVER, I thought I saw a photo of an A65 with an OIF front end and a '67-ish front wheel. Unfortunately I can't find the photo now, but does anyone know if this is possible?

Most anything is possible. Are the stanchion centres the same distance apart? If so then one thing to fix is the axle cut-out for the holding studs.
The '71'/'72 sliders have four studs with the inner two intersecting the axle. The earlier sliders have two studs centered on the diameter intersecting the axle so you either have to make a new axle or modify the existing one.
The brake anchor is another. There is one on the twins but the B50 trials version has two, one for the comical and one for the small 6" brake.
For the steering tube, press it out, modify and press it back.

I think Mark is referring to the last of the BSA twins, the T65, this used the OIF forks with the earlier 68 - 70 front wheel, presumably the OIF wheel spindle fits the earlier wheel hub, or is modified to fit. https://cdn.nettimoto.com/live/2362893/BSA---d973119657e6fec9-large.jpg

The answer to life, the universe, and everything is on youtube!



I basically did this and it worked just fine.
I did eventually buy a conical hub and laced on to it a 21" wheel, for no other reason than I wanted to! Don't be afraid of building your own wheels, it really is pretty simple. you dont need any special jigs, just do it in the bike.

Not A65, but OIF forks fitted to B44 frame using early BSA front wheel (unknown origin)









I did the same as Mike Waller did in the video, but with different front wheel.

Tom

That is very helpful, thanks! And the video too, Dave.

Yes, I may have to have an axle made, if the OIF axle won't work - my '66 axle threads through the right-side fork leg.

This is the image I gave to the machine shop to get the oif axle to fit my wheel. They actually didn't touch the axle, they just reamed out the bush on the left to fit.

I started watching the video tonight, and check this out: The producer of the video, Mike Waller, lives only about 25 miles from here! So I might be able to get some help directly from Mike, especially since I don't myself have a lathe. He's formally retired now, but he may be willing to take on a small job such as this.

In regard to the steering head bearings, I believe there's a conversion kit available now, so machining for that might not be necessary.

The conversion that Mr. Waller does, which is the same that I did, is just a sleeve to adapt the tapered bearing to the older steering neck. The outer race of the tapered roller bearing actually presses clear down to the reduced section of the neck. It would be nice to leave a small seat at the bottom for the race to bear on, but the OIF steering stem is barely long enough to work in the old frames, so the ledge has to be minimal. It's pretty simple for anyone who has a decent lathe, especially if you start with the extra thick wall tubing that he uses. The only shortcoming that I see, which is the same as I did, was in not making that sleeve tall enough to completely capture the seal above the inner bearing. But I have to agree, if he lives close, he will be an invaluable source as he has made some really nice custom bikes, mostly trials types.

Tom

The kit I was referring to for the steering head is something I saw offered by a shop in England, and I believe it was a pair of bearings with the correct inner and outer diameter, so no sleeve or machine work is required. What I'll be approaching Mike Waller about is the axle conversion.

Possibly these will fit.

https://www.ebay.com/itm/282325709617?hash=item41bbec7331:g:G0IAAOSwZVlXszY9

I think I heard that with these bearings, the original OIF steering stem may be too short.

So when I did this to one of my B44s I got the kit (and forks for that matter) from Peter at BSA Unit Singles, I believe it was an SRM kit. No machining was needed, straight forward fit. Don't know how applicable that is to the A65.

As far as the axle ....... honestly, as you have a hub that fits the forks the easiest thing is to lace a new rim to it. If you can lace a pair of shoes, you can lace and true a wheel. The whole mystery and magic surrounding the topic is completely unfounded. Do it in the frame and all the mysterious things like "off set" disappear!

As he was turning the top hat wheel spacers on his lathe, he could have easily made another spacer for the brake plate side with a thicker rim by that 1/16" that would have pushed the wheel bearings etc of the required amount, then made the spacer on the other side accordingly. No messing with the offset required.