Another thing I just read

[soonerbillz]

Again tripping on FB groups and a fellow asked if there were any differences between the R5 & RD350 frames.
Then this answer.

[Arrow]

I know this Guy. He's very unlikely to be wrong.

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[soonerbillz]

I know this Guy. He's very unlikely to be wrong.

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No doubtful just don't know because I never seen anything about it anywhere.
I know the TD & TZ frames were way lighter and had different head stock angles. So I'm thinking the race bikes used chromoly.  What could be material different on the street bikes?

[Arrow]

I'm not sure, myself.

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[m in sc]

Totally disagree with this statement, and uwe is on here. they are otherwise the same having have cut on both of them and welded on both, he's flat wrong. tube dia the same, wall thickness the same, etc.  you think they got different grade metal for the 2 for a what, 4-6hp difference? makes no sense.  the main noticeable difference is the lack of a reflector hole r5 to rd 250/350 that has one.  frame geometry is absolutely identical.   Of course, this is us models im referring to. early tz? yes different.

[sav0r]

That steel of the era isn't particularly good. Hence the absurd wall thickness. Even if there is some change in metallurgy, it's not large enough to worry about. Otherwise the wall thickness would have been reduced.