David Bean wrote:
> Going thru my collection of old freewheels, I found an Ultra 6-speed
that
> isn't too worn. I haven't used one of these before; should any chain
made
> in the last 10 years or so be narrow enough to work with it? Is there
> something I should measure/check?
I recently installed a Shimano 9-speed chain on my Masi GC with Ultra-6 freewheel and the shifting has never been this good. The previous 7/8-speed Shimano HG chain worked ok, but was annoyingly much less forgiving as far as needing a more exact lever position, which slowed shifting. Fortunately, this 9-speed chain is also working fine at the front over the NR chainrings (and derailer), handling all of my most intense riding over hilly terrain just fine.
Suntour's Ultra freewheels have similar cog spacing, but thicker cogs and narrower spacers than Shimano's 7-speeders, and seem to need a narrower chain as compared to the Dura-Ace 7s freewheels. The 9-speed chain is wide enough INTERNALLY (measures same as 6/7/8-speed) to engage Suntour sprockets, but the narrower exterior width means less contact with adjacent larger cogs, so shifting is more forgiving as far as lever positioning.
I've also used the same HG93, 9sp chain with six-speed Suntour freewheel, and even on my four-speed Moyne freewheel with excellent results, even with a steel 1950's Stronglight chainset! I have had problems with Stronglight 93 and SR Apex cranksets when using
anything as narrow as an 8-speed chain, but Campy NR and the old steel Stronglight parts worked fine.
David Snyder
Auburn, CA usa