Aha, in that case, what I'd do is head down the local autofactor with your stat, and go through all the ones in the shop till I found one the same. Maybe do that at a bike breaker, as once you've found a match you can go buy a new one.

Personally, I'd start by looking at things like the Suzuki or Yamaha 250's, or the 400cc 4 strokes. They all came to market about the same time, and I'd be surprised if they each had totally different thermostats.
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