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Old 10-11-2012, 12:07 AM   #8
Boxer Metal
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Joined: Nov 2003
Location: Chico, California
Oddometer: 3,570
Originally Posted by sigpe57 View Post
I have an extra 19" r80st wheel. If I ask the wheel builder to put on a new 21" rim plus longer spokes, will the new wheel be exactly the same as a '21 r80g/s wheel?

After that, if I put this newly build wheel on a R80ST, will this R80ST have the exactly same suspension setup as an R80g/s? I will also replace the shock with a r80g/s shock, of course.

Thank you for the reply,

The answer to the first question is Yes and the brake disc is the same as well.
Answer to the 2nd question. You can look in the Clymer or Haynes manual to see what the suspension travel is between the G/S and the R80ST or R65.

Some one made reference to the brake caliper which should not make a difference in you application.
The G/S has the same offset and mounting pattern as any 81-84 R80 or R100. The R80ST as a further apart mounting pattern than above just like the R65 and a different offset. The R100GS is a lager piston and different offset than any of the to mentioned above.

If all you are doing is lacing a 21" rim to your ST then there is nothing to change. The lower fork legs on the ST are the same as the R65 from 79-84 with the axle located at the bottom of the fork slider. A 21" front wheel will make the bike handle quicker. You will to address the R80ST fender brace. The 21" front wheel is to tall I believe.
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