6 speed indexed freewheel to cassette

I’ve a bike with 6 speed freewheel and indexed downtube shifters I’d
like to do some ratio customizing on. Could grab another rear wheel
for quick swapout as an alternative to going to 7 speed shifters.

Considering with a freehub: obtaining a 6 speed cassette, and mixing 7
speed cassette sprockets with the 6 speed spacers.
Will that fit properly on the hub?
Will it index properly?
Will the wider spacers effect Hyperglide timing any place I use
adjacent sprockets from the same original cassette?

Not sure if I’d ever use it, but if I ever have cause to select an 11T
sprocket from a Hyperglide-C hub, can an 11T sprocket work with a 6
speed cassette-hub?

Thanks


--
meb

meb wrote in message ...
I?ve a bike with 6 speed freewheel and indexed downtube shifters I?d
like to do some ratio customizing on. Could grab another rear wheel
for quick swapout as an alternative to going to 7 speed shifters.

Considering with a freehub: obtaining a 6 speed cassette, and mixing 7
speed cassette sprockets with the 6 speed spacers.

I assume you're going to get a 6-speed cassette *hub*.

Will that fit properly on the hub?

Sort of. If the 7-speed sprockets are hyperglide, and the hub is the
the older Uniglide style, you'll have to grind down the one wide
spline on the Hyperlide sprockets.

Will it index properly?

Yes. Indexing depends on the spacing between sprockets. Since the
sprockets are the same thickness, only the spacers are different.

Will the wider spacers effect Hyperglide timing any place I use
adjacent sprockets from the same original cassette?

No, as long as you keep the Hyperglide register marks lined up. In my
experience, mixing and matching Hyperglide cogs is not that big of an
issue anyway.


Not sure if I?d ever use it, but if I ever have cause to select an 11T
sprocket from a Hyperglide-C hub, can an 11T sprocket work with a 6
speed cassette-hub?

Probably not. The 11-tooth sprocket fits on a relieved area at the end
of the cassette body. A 6-speed cassette body will not have this,
since it predates Hyperglide and Hyperglide-C.

There were some 11-tooth sprockets that threaded on, but they and the
matching cassette body were Dura-Ace *only*, came out in the early
'80's, and are as rare as pork lips.

Jeff

meb wrote:

I’ve a bike with 6 speed freewheel and indexed downtube shifters I’d
like to do some ratio customizing on. Could grab another rear wheel
for quick swapout as an alternative to going to 7 speed shifters.

Considering with a freehub: obtaining a 6 speed cassette, and mixing 7
speed cassette sprockets with the 6 speed spacers.
Will that fit properly on the hub?
Will it index properly?
Will the wider spacers effect Hyperglide timing any place I use
adjacent sprockets from the same original cassette?

Not sure if I’d ever use it, but if I ever have cause to select an 11T
sprocket from a Hyperglide-C hub, can an 11T sprocket work with a 6
speed cassette-hub?

A six cassette hub has threads on the outside for the
screw-on high gear. 11t cogs are splined.

Six is a rather forgiving format. I liked your idea of a
later HG type seven hub with six cogs better. If you reuse
any old type cogs, they will need a small modification -
trim one spline - to fit newer bodies.

Within normal limits ( not excessive range and an
appropriate length derailleur) you should be OK. The HG
ramps are a positive enhacement, won't cause any difficulties.

A wider six speed 7.8mm chain is a good choice here with an
older changer. Skinny chain degrades shift response at the
upper roller/cage of an otherwise classic six system.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971