Tire Suggestions

At Scottie's Workshop, we regularly use two common tire brands on /2 era BMWs. 

Avon Am26 Roadrider for all kinds of riding. Quiet, smooth, very very good traction. Great braking. Good in the wet. No real complaints. 

Heidenau K34 - for that "vintage look".  A good show tire for concours events.  Very soft riding - even a bit squirmy. Squeals under braking.  Will "hunt" and "track" rain grooves aggressively. Inferior to the Avon at over 50mph. But they look great! 

Both tires are about $100 each. 

For older bikes, we will either use the Avon AM26 for regularly ridden bikes, or the Avon Speedmaster II front and rear combination for show bikes. 

Got a favorite tire suggestion for Vintage BMWs?  Let us know in the comments!

Checking for a bent frame

If you are rebuilding, repainting, or restoring, it is highly advised to inspect the frame for bends. If you know (or suspect) that the bike was involved in a crash, or if the bike rides crooked (rides straight but the bars are cockeyed to one side), if it takes more effort to turn left vs. right (or vice versa), or if, when riding the bike down a straight and level road, the bike is leaned one way or the other in order to make it track straight, you must inspect the frame. Something is probably bent. 

Now it could be your frame is bent.  Or it could be the fork, or front or rear swingarm.  Or the handlebars could be bent. This procedure only focuses on determining if the frame is bent. 

This procedure is well documented in the Barrington manual, which is a highly recommended book for mechanics of vintage BMWs. 

First obtain two straight tubes or rods. One must fit through the steering tube. A fork tube works nice for this. The other must fit through the rear swingarm pivots in the frame. I went to the local metal yard and picked up some stainless steel tube for this, but anything strong and straight will work well.

Next you'll need a carpenter's square, a C-clamp and a few bungie cords. 

Arrange the smaller diameter rod through the rear swing arm pivots and bungie in place. You want to ensure that the rod is pulled in the same direction on both sides so that it sits square to the travel line of the bike. Bungie it in place. Now clamp the square to the rod so that you have a perpendicular reference. Arrange the square so that it is positioned in the "window" of the battery tray. See photo below. Click to enlarge photo. 

What is important here is that the carpenter's square gives you a good perpendicular reference to the plane formed by the rear swingarm pivots, and also that you can see the reference in the window of the battery tray.  (See photo below).

Now arrange your larger reference straight tube through the steering head and bungie it in place. Again you want to ensure that the tube sits square on the upper and lower bearing race lands in the same spot. I think it's easy to pull it back towards the back of the bike, and then bungee cord it in place. (See photo below.)

Now that you've done this, you can compare the two vertical lines formed by the carpenter's square and the tube going through the steering tube.  If it is not exactly lined up, check your reference tube positions to be sure they are positioned correctly, and check your square to be sure it is settled in place. 

If the frame appears to be bent, then you'll need to take the next step which is to take the frame to an alignment shop and have it measured with professional equipment, and straightened, if necessary. 

Puller animation

SOLD! Michael's 1931 R11 Partially Restored

The bike has been partially restored and mechanically fixed to get it running by an unknown professional vintage restorer. Much of the wiring has been restored with proper cloth wiring. And yet some items remain unwired, such as the horn. There is enough wire left there, and spooled up to permit easy termination. I have not seen the bike run, but the engine turns over, and has good compression and seems like it would run if it had fuel and spark. The previous owner reports that it ran, but I have no confirmation of that.

There are many parts on this bike that are original, some restored and some which are from the subsequent 1930's R12 model.  Foot boards and exhaust are nice correct reproductions in great condition. The wheels are freshly restored and the tires are nice. The rear brake clamp is missing friction material. The throttle assembly is missing.

The paint is fair to poor and the tapes are stripe. However, stripping the stripes off and painting proper stripes on would go a long way.

Original seat and new Drillastic seat cover with logo plate is included.

Cap on air intake to bell housing is not original.

I am assisting in selling this for the owner. He is firm at $15,000. Will ship worldwide.  Contact Scottie for details.

Click on photos to enlarge them.