Yep definitely a Davidson, model name Challenge, probably '83-'84. That was a small-batch production road racer. Tange Champion, tube gauges vary by frame size but mostly equivalent to #1. Rear OLD 126mm, 27.2 seat post.

By the next year, the Challenge was mostly replaced by the Impulse, which was pretty much the same frame only with the more racy looking "MER" crown, and made of Prestige instead of Champion. Same steel only heat-teated, and maybe some lighter gauges here and there (I don't remember).

The Challenge remained on offer after the Impulse came out, but not too many were built or sold; most people wanted an Impulse.

Later Challenge frames got cooler seatstay tops that were investment cast with the Davidson name cast in relief, sorta pantographed-looking. That's why I don't think yours is newer than '84, maybe '85 at the latest. Though it might have hung on the ceiling for a couple of years before it sold.

Forks and rear triangles were made by Tange, and even the main triangle tubes came mitered at both ends by Tange, to Bill's specs. They were very quick to build, with the nice Takahashi lugs that needed almost zero prep before brazing, and almost no cleanup after brazing either. The lugs were not "thinned", they were cast that way. We pretty much perfected the art of lug brazing, getting the time to braze a lug down to under 2 minutes on average, with zero blobs or spatter, just nice clean shorelines that needed no filing, pretty much ever.

Champion is great steel, and I actually prefer the "HNR" crown on the Challenge over the MER on the Impulse, so I rate a Challenge as a great production frame.

I guess you could say I'm biased, but I never actually built any, they were built by the rest of the crew, while I made the one-off custom frames, which eventually became known as the Signature model. I did help a lot with making fixtures, developing processes and training the crew, but it was definitely Bill's baby. His design, his vision.

Mark B