Thanks GULG.

Due to me losing all my Ten' pic's when the PC died, I can't recall the exact weights of the original and the single can and I can't be arsed to take it off to weigh it now!

Like you, I'm interested to hear an expert's opinion about gas flow 'n all that. I also fitted Kev's fuel mod and the K&N air filter so other than a PC now, I just have the baffle to take out. Silencing with the standard baffle is more than adequate.