Unidentified frame - just found out it's a Rotrax

[3wheeler7]

Hi, my son in law has a Rotrax that his sister saved from a skip, I've been telling him for years that I'd help him rebuild it but to no avail.
Anyway, for almost a year I've had a few frames sat in the garage that I couldn't identify but yesterday I found out that one of them is ......... you guessed it ....... a Rotrax.
Don't know the model yet but hope to get in touch with the V-CC Rotrax ME who may be able to shed some light on it.
Frame and fork number is 46 371 which makes it a very early one - as they didn't start until 1945.
It's generally in very good condition, nice and straight, so it'll go in the queue for a rebuild with some near period parts.
looks to have been built for 26" wheels as the 27s in the picture are a bit tight on clearances.

 

[Jonny69]

Nice discovery! To my eye it looks fine with the 27's. Earlier bikes had huge gaps but that doesn't look excessively close to me. What's the brake caliper to rim fitment like with something like a Weinmann 700 (long) or 500 (short)?

 

[3wheeler7]

Hi, I don't think I'll be fitting mudguards to it so I'll probably stick with 27s as I've got a few pairs doing nothing at the moment. but it's strange how narrow the rear chain stays are - with 27" x 1 1/8" tyres there's only about 1/16" clearance each side.
A Weinmann 500 will fit fine on the front but I'd like to find something earlier (more in keeping with the age of the bike) I've tried GB Sport and Sport Mk 2 but they're both about 3mm too long, so maybe 700c rims would be a good compromise - and solve both problems.

 

[Jonny69]

1/16” is way too tight. In which case it might well have had sprints originally.

 

[3wheeler7]

That was my thinking, or it was made for 26" x 1 1/4" wheels.
I'll do a bit of testing with various combinations and see which works best, but good 26" tyres are few and far between.
One interesting feature on this frame is the pump pegs fitted to the front of the seat tube - I've not managed to find another Rotrax with that feature but then I've not managed to find another 1946 one!

 

[Guinessisgoodforyou]

At that age I would think 26x1 1/4" wheels. Check the b/b height, if its over 11" it will be 26" wheels.

 

[vcballbat]

Interesting frame from Rotrax, first one I've seen with a clip style headset. Fairly common to have one bike for racing, touring and the ride to work swapping out the 26 inch wheels for racing sprints and tubs. Rotrax Cycles in Shirley Southampton was a mecca for me as a budding schoolboy racer, had my first set of sprint wheels built at the shop in the 70's

 

[3wheeler7]

Here's another with a clip headset, this is a 1948 but not the same model.

 

[vcballbat]

Here's me and my 1961 Jensen Italia outside the old shop in Shirley Southampton back in 2019 when the shops earlier history was revealed, luckily the old Bill Harvell signage has been saved

 

[vcballbat]

Guess that your frame was built soon after the birth of Rotrax Cycles in 1945...

https://www.classiclightweights.co.uk/reminiscences/an-appreciation-of-bill-harvell/