twin tube frames for 45 racers.

I was intrigued by the picture of the twin-downtube frame 45 racer lately posted in the foot-shift thread.

I do know that H-D produced a limited number ( probably 25 ) of a bike listed as the DAH in the late 20s or early 30s, incorporating a special ohv conversion and in at least some cases, a special twin down-tube frame. At least one bike appears to have been fitted with a springer fork converted to trailing-link operation. Given the detail differences between the remaining specimens, I rather get the impression that it was really a series of factory competition bikes using the ohv conversion engine as the only assembly common to them all.

the bike shown on here has a very modern-looking frame which appears to be an all-welded tubular frame, as far as can be seen. The rear axle detail appears to have a flat axle plate with straight tubes welded along the top and bottom, much as modern custom frames often have.

Does anyone know anything about this frame or any contemporary units?

thought the axle plates looked like wl type

hard to be sure, from the available definition. One thing though, the angle between the upper and lower chainstays doesn't match a WL or WR - the lower chain stay would come to the back of the gearbox at or about the same level as the crankshaft.

It makes me wonder whether it is either a modified Big Twin chassis - given that this would be about the same weight as a 45 unit, apparently - or a 45 chassis with a fabricated front and lower frame grafted on. I'd go for the first option.

The bike is a factory experiment, designated WRL.
The frame looks like a one-off, no cast parts by the look off it.
Nice high pipes! The front jug looks reworked.
The lever on the 'bars is the clutch - no brakes.

For some reason, it didn't take off.

http://books.google.co.uk/books?id=7KfX ... &q&f=false

Believe it was scrapped for the K-model..

Believe it was scrapped for the K-model..

It was dropped years before the K was thought of.

I don't know why, but the introduction of all-welded tubular frames is definitely a post-WW2 phenomenon; look at the change BSA made from the lug-and-tube rigid and plunger frames to the all-welded, tubular A7 and A10 frames, or Norton's adoption of the Featherbed. I assume it's to do with war-time developments in welding procedures?

'Parently that was an aluminum frame... an experiment that ended in the jaws of the crusher, as one that didn't work out.

https://www.sscycle.com/tech/viewtopic. ... &sk=t&sd=a

Does anybody have a connection in the H-D archives? If you can get to the photo archives look in a group of photos from 1946. They are in the negative number range of about 17025-17040. This is a batch of photos listed as "County Fair", if memory serves correctly. There are pictures of Chan, Anthony and other riders on these twin downtube machines. A group shot of several of them together prove that more than two were built. I have neg numbers 17028 Jimmy Chan left side, 17035 Leo Anthony left side , and 17036 again with Leo Anthony right side. I saw the negative in that group with a line of several WLR's but didn't order a copy when I had the chance.