fisher@banzai.DEC (Ed Fisher, 381-2377) (04/09/85)
A few comments on the subject of freewheels:
Some of my experience here is based upon hearsay, some upon personal
experience. My first bike (a Fuji S-12S) had a Suntour perfect
freewheel. They are soft and brittle. I've known two people who have
broken cogs on Perfects. The cogs are cheap but I decided that I did
not want to risk a weeks vacation on something that was likely to
break when I had gotten to a maximal distance from a bike shop.
I replaced the Perfect with a Suntour Winner freewheel (14-32) and got
satisfactory service. I have been told that the Winner is relatively
soft and often worn out by some very hard chains, such as the
Sedisport but I never got that many miles on the Winner. The winner
is now on my daughter's bike. It may never wear out there.
My current touring bike is a Trek 720. It comes with a Maillard
Helicomatic freewheel and Maillard hubs. This is a special
combination that makes it easy to remove the freewheel to replace
spokes or change freewheels if you have a couple of them. The real
advantage to the hub is that the bearings on the axle are out much
nearer the drop-out so that it is much less likely that one can bend
or break the axle. One of Shimano's hubs has the same feature. I have
toyed with gearing on the Helicomatic a bit.
The cogs have split teeth for good shifting. (As opposed to the bent
teeth that some have.) I had trouble shifting this a few times and
eventually discovered that it was because of "wax buildup". Over the
thousands of miles that I used it the wax from my chains had filled in
the splits so that they no longer served their purpose. The cogs are
a bit closer together than they are on conventional freewheels so you
must use a narrow chain. The Sedisport is the correct nationality
(French) and works fine.
As for, "What cogs do I use?" The Helicomatic came as a 6 speed
(14-16-18-21-24-28). In the search for the ever-elusive lower gear, I
changed the bigger cogs to 25-30 and then 26-32. Sometimes I would
switch back to 24-28. It is currently a 7 speed
(13-15-17-20-23-26-30). The spacing is the same on 6 and 7 speed
models, the small cog comes in a 12 or 13 and threads into the next
one -- but you have to replace the other cog and the lock ring.
What do I use for chainwheels? Half-step plus granny, 24-45-50.
The half steps may not be quite right by now. The 24 is not used
as much as it once was. I do remember a few rides up Mt Washington
where it was useful. I cannot remember what I used on the down
hill trips, if anything.
Oh, do not even think about a helicomatic 600, replacement parts
are too rare. The 700 is the good one.
On my racer (a Guerciotti SLX), I have a Regina CX-S. The cogs also have
split teeth. The chain (CX-S) and the freewheel are said to be
"match hardened" for "uniform wear." When a Sedisport chain gets
a spot of rust on it, I am tempted to just throw it away because
thay can be found for $4-5 but the CX-S chain is usually $25+ so
I take better care of it. -- I am less likely to be caught in the
rain with the Guerciotti, also.
I noticed a remark about removing freewheels with two-pronged
adapters. They are very difficult to remove but there is a trick that
makes it much easier. The problem with removing a freewheel such as a
suntour is that the little removal tool has two very small pips that
fit slots in the face of the freewheel. When you really torque down
on it with a big wrench it is likely to slip out and a few of these
twists and you start wearing out the face of the freewheel. Put the
remover on the freewheel and put the quick-release back into the axle
so that it is semi-tight on the remover. NOW put your big wrench on
the remover and push. You will still have to sweat. As soon as the
thread-bind is broken, loosen the quick release skewer a bit and then
the freewheel. By now you should be able to just remove the QR and
unthread the freewheel. The Helicomatic does not have this problem.
The Regina is splined so that it needs the sweat but not the QR trick.
Before you put the freewheel on (or back on) Grease Those Threads.
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