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Suntour Ultra/NWN Freewheel ?(4 posts)

Suntour Ultra/NWN Freewheel ?hdnoise
Apr 18, 2003 4:10 PM
How does one remove and replace cogs on these. Unwind like the old reginas? I see what looks like tabs in the two prong removal slots. I also see a larger two slotted threaded ring around the inner ring. I wonder if these two lesser rings are applicable to the inner mechanism and independent of the cogs? Any help is appreciated. I know there were diagrams on the old boxes so a fax or email of same might answer all for me. BTW I am upgrading from 5 to 6! Frejus.
re: Suntour Ultra/NWN Freewheel ?eddie m
Apr 18, 2003 5:48 PM
I was always able to replace cogs by unscrewing the 2 or 3 smallest cogs. The 3 or 4 largest were always on splines, held in place by the threaded cogs.
re: Suntour Ultra/NWN Freewheel ?M_Currie
Apr 19, 2003 9:14 AM
On a Suntour you always start by unscrewing at the small end, but the number of cogs that are screwed on can vary a lot. On most, it will be the first two. On a Winner or Winner Pro 7-speed, the smallest cog screws onto the next one, so the SECOND cog is the one you must unscrew from the freewheel itself, followed by the third. On a "New Winner," which is actually older than a Winner, the first 4 may be screwed on. Generally, the only one that's really hard to get off will be the outermost one.

A pair of chain whips will do the job, but a freewheel vise is nicer. For mine I bought a cheap drill-press vise, drilled holes in the tops of the jaws, and inserted pins (actually large alloy motorcycle spoke nipples) into the holes. Depending on the size of the cogs, I can either hold the largest cog by its teeth, screwing in the jaws of the vise, or put the pins into the webbing of the largest cog and hold it by screwing the jaws out.

Be prepared for a dizzying array of different cog and spacer options in Suntours. Most cogs are identified by a letter prefix, which is important if you're trying to find a replacement, because the same size cog might come in multiple screw and spline versions.
re: Suntour Ultra/NWN Freewheel ?hdnoise
Apr 24, 2003 10:41 AM
Thank you