I am thinking of getting a Yamaha TDM (so slick) but I had a new '91 NSR 150 once and they're a bit light and bog down under 4,500 rpm so I expect the TDM would be similar and a four-stroke engine swap would spoil the look too much. Anyone know enough to compare them?

Alternatively, does anyone know of a good-looking motor to suit with the usable performance of, say, the old RVFC 250 as used in old XRs?

Perhaps I could just respray a TZM in eyeball-searing red, paint most everything else black and hide a CBR150 engine under the fairing: anyone done this or thought of it?

RAW.

Go and have a chat with Ohm at Ohm's motorcycles on the ring road at Chawend. Good luck

I can honestly say I haven't a clue what you are talking about , but wish you luck all the same!