On Wed, 07 Dec 2005 21:46:41 +0000, Steve W wrote:
> Quote from SB web site:
>
> "Shimano Hyperglide freewheels use all splined sprockets, with a
> threaded lockring, similar to the system used on Hyperglide cassette
> hubs"
>
> I need the tool to undo the lockring
In a pinch you may have success with large Vise-Grips, clamped
to the outer edge of the lockring. Try holding the cogs by wrapping them
with a rag.
You can get the regular spline tool at most bike shops.
But better than that is a portable one, like the old Pamir Hypercracker:
http://www.sheldonbrown.com/harris/stein-mini-lock/
Let me explain why. First, sometimes you can just wrap the cogs
with a rag, but if the lockring is tight you may need a chainwhip.
Second, if the lockring is really tight, it's easy to strip the splines --
especially if you're using the other hand to hold the cogs.
A Hypercracker-type tool solves both these problems. It uses your bike's
chain so it eliminates the need for a chainwhip. Since it's sandwiched
between the lockring and the frame it cannot slip or strip. It takes an
extra step (putting the wheel back in the frame), but it's practically
idiot-proof. Therefore I believe it's a better choice for a home
mechanic. Plus it takes very little space in your toolkit.
If you're lucky, you might find an original Hypercracker for a few bucks.
This is one tool I refuse to lend!
Finally, there's no reason for the lockring to be super-tight. Don't
tighten it too much, and it will be much easier to remove the next time.
Matt O.