I agree. On a touring bike I'll usually have a 14T small cog, sometimes even 15. This can be a big problem in terms of the chain rubbing on the stay as well as in removing the wheel. Most Japanese FW's make the situation worse as they have a flange at the base of the FW body that is inboard of the large cog. This pushes the whole FW a few mm further out and reduces chainstay clearance accordingly. Many old French FW's, and I believe the classic Reginas, have the outer cog flush with the FW body, so they give more clearance.
Regards,
Jerry Moos
Big Spring, Texas, USA
> From: Andrew R Stewart <onetenth@earthlink.net>
> Subject: Re: [CR] Freewheel re-spacing
> To: "David Snyder" <dddd@pacbell.net>, classicrendezvous@bikelist.org
> Date: Tuesday, December 29, 2009, 9:53 PM
> David- The gap between the chain
> lifting off the smallest cog and the inside of the seat stay
> end is a must to avoid a nasty nick in the stay end. The
> minimal dimension from the hub's free wheel seating face to
> the axle's locknut will vary due to a few factors. (And the
> hub presets the seat face to flange dimension). Of course
> the cog count is the biggest part. But when getting down to
> the last few mm's the small cog diameter/tooth count and the
> stay's end relief (if any) are the real limiting factors. A
> 14 tooth small cog with a non relieved stay end can need 2
> or 3mm more then a 13 tooth cog with a nicely profiled inner
> stay end.
>
>
> ----- Original Message ----- From: "David Snyder" <dddd@pacbell.net>
> To: <classicrendezvous@bikelist.org>
> Sent: Tuesday, December 29, 2009 10:31 PM
> Subject: Re: [CR] Freewheel re-spacing
>
>
> > Actually, you really don't need 126mm to run 6-speeds
> and still have reasonable wheel dish.
> >
> > Most 6-speed production bikes showed a curious lack of
> precision in that the outer face of the smallest cog was not
> close to the ~3.3mm minimum of space needed between cog and
> dropout. Result was that one could easily remove 2mm
> from both ends of the wheel's axle spacers (down to 122mm!)
> and still have all the clearance needed, especially once a
> modern, narrow chain is substituted (just don't use a 14t
> small cog, on certain frames that will have the chain
> hitting the end of the seatstay during the last shift).
> > So, a modestly-dished wheel measuring 122mm (easily
> slid into any 120mm frame) should easily accomodate a
> 6-speed Shimano UG freewheel. All that is needed is a
> bit of fine-tuning to the axle (and any freewheel) spacers,
> all part of a reasonably well-built, purpose-built wheel.
> This isn't radical at all! Just look at the huge amount of
> wasted space that many 5-speed freewheel-equipped bikes left
> unused: enough to throw your chain to the axle!
> >
> > David Snyder
> > Auburn, CA usa
> >
> >
> > ----- Original Message ----- From: "Thomas Adams"
> <thomasthomasa@yahoo.com>
> >
> > Subject: Re: [CR] Freewheel re-spacing
> >
> >
> > Dear Don and List:
> >
> > Yeah, you can re-space a 120mm to 126mm, but is it
> morally right? Especially with really old frames, which
> never would have been available in 126mm rear spacing.
> > _______________________________________________
>
> Andrew R Stewart
> Rochester, NY