[Bilgemaster]

This one asking $1,200 on Richmond, Virginia's Craigslist caught my attention. Seller claims it's a "500cc single." It's hard to tell from the ad's 2 photos, but the engine resembles a 250cc TR25W, which was one of those BSA/Triumph post-merger mashups using what was basically a BSA Starfire 250 engine. Still, it does look like it was no stranger to the raceway, and owner claims "engine has new rings turns". So who knows what it might be? Those 1-into-2 pipes are certainly curious:

https://richmond.craigslist.org/mcy/d/richmond-1971-triumph-trophy-ex-racer/7243703030.html

[AzCal Retred]

Mebbe the translation was supposed to be "Has new rings, turns over"??
Here is a B50 and one with "Twin Silencers". Maybe one is tuned for low speed, the other is high speed?
All I know is this machine has 'Da Bilgemasters Chiropractor dreaming of a new ski boat...

[Adrian II]

The TR5MX is a thing, last-gasp badge engineering to sell off the remaining BSA B50MX bikes circa 1972. The twin muffler was the only real difference.

A.

[Guaire]

The TR5MX is a thing, last-gasp badge engineering to sell off the remaining BSA B50MX bikes circa 1972. The twin muffler was the only real difference.

A.

Yes, this was “badge engineered”.
  Looks like a T25 to me, not a 500. The B50s were round barrels.

[Bilgemaster]

Thanks for all the info! I'd never seen nor even heard of that Triumph TR5MX model. Now that I can see better pix with a Google search (Try: https://www.google.com/search?q=tr5mx+triumph), I am struck by how much it resembles my old BSA 441 Victor Special.

I guess that thing might be fun on a farm or ranch.

[Adrian II]

Yes, this was “badge engineered”.
  Looks like a T25 to me, not a 500. The B50s were round barrels.

Er, no! Early B44E and B44 GP Victors had the round fin ally barrels, same shape as the B40 iron barrels. The B44 went square fin for the B44R and B44 Shooting Star (name borrowed from the later A7 twins) and the B44VS Victor special, square fins continued with the B50. Apart from being physically larger than the B25/T25 top-end, they still have the single-screw cover for checking the inner end of the rocker seating in the push-rod cups. The B25/T25 have eccentric rocker spindles for tappet adjustment. held on by two screws.

B50SS



B25SS



A.

[Richard230]

Did someone mention Shooting Stars and Victims?   

[AzCal Retred]

I'm sorry - were there motorcycles in those pictures? I was distracted...

[zimmemr]

The TR5MX is a thing, last-gasp badge engineering to sell off the remaining BSA B50MX bikes circa 1972. The twin muffler was the only real difference.

A.

In December of 1972 I attended one of, (maybe the last) service schools to be held at Triumph's Baltimore, or more correctly Towsen headquarters.
On the last day of the school, Herb Neas, the service manager at the time brought us out to the warehouse where they were loading everything for the move to Duarte, Calif. There were stacks of Avengers, and he offered them to us at a one time, cash deal of $500.00. Of the dozen or so guys in the class, including a few shop owners, not one of us bought a bike. Year's later I built one for a friend to ride in AHRMA. The went well, and we won a few races with it, but it was finicky, far more so than any of the Victors and 250's I'd built and heavy as a tank.