I have a GT650R as well as a GT250R, and the wheels off the 650 go straight on the 250 and it rides really well (well the front does at least.) After more than just a glance and a quick measure, I'd say the rims were identical.
I'd say you were perfectly ok putting GT650R spec tyres on it. They are a lot lower profile. Dunno what this will net you overall though, unless you went to some sticky modern-technology like a Michelin.
Steve
"I am a licenced motorcycle instructor, I agree with dangerousbastard, no point in repeating what he said."
"read what Steve says. He's right."
"What Steve said pretty much summed it up."
"I did axactly as you said and it worked...!!"
"Wow, Great advise there DB."
WTB: Hyosung bikes or going or not.
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