Help figuring out what I have

Here you can talk about all kind of TECH for the B50 B44 B25 And Other BSA unit Singles

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Help figuring out what I have

Post by TheSpiritOfVali » Wed Jan 15, 2020 4:29 am


I picked up a BSA b25 a few years ago. Despite my knowledge about B44s and B50s, I don't know much about B25s. I was hoping someone could help me shed some light on this bike! What I know so far is:

It's a 1970 BSA B25

and that's about it.. Just kidding I have kind of figured out some more details here and there.

Here is the bike in question:
I have identified the tank to be like this b25 I have found while searching the web.
I really couldn't find any information about this specific style of B25. I'm actually not sure there is enough there to where that matters!

If anyone could tell me the origins of that odd-looking b25 I would greatly appreciate it! I also am curious to what the thing is actually worth. I recently came to the realization that I have way too many projects and I need to downsize. So it's either this or a pair of triumph cubs that should go! (I am bias to BSAs though) So far I have built up a full wiring harness to fix the nonexistent one. There are also a few more parts that came with the bike that aren't in those pictures.

Thanks for your help everyone!

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Re: Help figuring out what I have

Post by minetymenace » Wed Jan 15, 2020 9:26 am

Looks like a 1970 Starfire to me. Engine and frame numbers are always handy. To value it from a couple of photos and no other info is neigh on impossible, it is worth what someone will pay (an answer as good as the question), it is a rolling chassis with an engine of unknown provenance, so somewhere between three ton and a monkey.

Unless you want me to make you eat both your own buttocks, do not pose a Starfire or two Cubs question on a BSA forum >44
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Re: Help figuring out what I have

Post by kommando » Wed Jan 15, 2020 3:58 pm

Model year is the second of the 2 letters at the start of the matching frame and engine numbers, C is 69, D is 70, first is the month but that ran from Aug to July. So 69 model year ran in production from Aug 68 to July 69 etc.

Looks like a 70, why it does not look like the catalogue photo is crystal ball stuff but that was a US only version, a lot can and does happen in 50 odd years. UK ones looked different.

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Re: Help figuring out what I have

Post by Leif » Thu Jan 16, 2020 5:23 am

I don't really understand what you're asking? You've identified the year and model (probably correctly, from what clues I can see). Any "differences" in this model from previous years is purely evolutionary, and mostly cosmetic... actually very similar overall. Dump a 69 tank on it, and you'll see what I mean... that (and a fiberglass shielded exhaust) make up the "big" change. Your particular bike has suffered the indignities of years of previous owners.

Revolutionary design change came the following year, with the OIF B25.

Not an especially rare or valuable bike in the US, even in the best of conditions. You don't mention if yours even runs, so no way to give you any approximation of value.

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