This is a 1991 RS250 front end on my MC21 a few years ago:
The stanchions are 41mm, the same as the NSR, so will slot straight into the standard yokes (triples), but they are considerably shorter than the NSR forks, so really [at the very least] the RS gull-shaped top yoke should be used. To use the alloy lower yoke a custom stem is needed. This can be purchased from TYGA Performance if necessary.
This conversion would work on an MC18 or MC28 just as easily, and even an MC16 with a little jiggling. (This setup is actually destined to go on my MC16 at some point!) 1991 forks give preload, rebound, and compression adjustment... that actually works! (The standard NSR's range of adjustment leaves a little to be desired!)
You need the forks, preferably the yokes (at least the top one), suitable calipers (VFR400 NC30 will do if you can't get the HRC ones), 296mm discs (RS or VFR/RVF400/VTR100F etc.), axle, and spacers.
It's a great all-Honda conversion, and actually a more "friendly" conversion than the 1992~ USD forks, as you start losing steering lock. The later forks are definitely superior though.
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Andy.
NSR-WORLD.COM
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