Suntour 7speed cog availability?
 

Does anyone know of any sources to find old 7speed Suntour cogs? While taking apart a problematic freewheel, I broke a tooth on the 13t because it was so tight. I'd hate to turn this into parts because of my stupidity. I believe this is an Suntour "Alpha" freewheel. I saw on Sheldon Brown's site that a Shimano 7speed cog might work, so I may try that as they seem easier to find.
https://cimg1.ibsrv.net/gimg/bikefor...8038864a49.jpg

Where are you located?

I have most of the sizes. If you are local (portland, OR) I charge 1 beer.

Confirm it's an AP. Clean it, it should show these markings. There are other freewheels with 4 notch extractors.


https://cimg0.ibsrv.net/gimg/bikefor...6fa1ccacff.jpg

The 13T cog for a 7s Suntour freewheel can be hard to find in good condition.

I've come across a couple of such freewheels having a cracked (split) 13T cog, and never found parts to repair them.

Too many of the 7s Suntour freewheels seem to start with a 14t cog, and no Shimano cog will match Suntour's threading unfortunately.

I think that your freewheel will work fine with just one broken tooth, but may wear out sooner if it ever wears out at all.

Thank you all, I am in Denver and can definitely try to accomodate the beer. It is a 7-speed AP freewheel, cleaned it and confirmed. It also threads just the first cog, vs threading into the second cog like the 4-prong Winner freewheels.

Thank you! I can't private message anyone until I make enough posts, hopefully he sees this post.

Does the cog have a Winner cog equivalent? I've got a few spare 13T cogs of the E, S and U types.

Steve in Peoria

I don't think so, from what I understand the Winner cogs thread the 1st and second together? The AP/Alpha threads just the first cog onto the body. I should have taken pictures when I had it apart.

Eventually you will find another 7s Alpha 13-28t freewheel, but in the mean time, I believe you can ride for some years on the 13t cog having a broken-off tooth.

I would normally source such a truly excellent freewheel from either a discarded bike or from a bike co-op type of place, usually found in a good-sized city.

Discarded bent wheels are also often found near urban encampments, and if there are "residents" there, a few dollars might get you the exact part that you need.
No joke, I have sourced valuable parts this way. Oh, and don't forget to visit any bike swap meets in your area. N+1 Baby!

Totally. I was just at the bike co-op today. They had lots of freewheels, but no Suntour ones. I took it apart initially because it was "skipping" in the last 2-3 cogs under high load. I tried watching and it didn't look like the chain was jumping, so I assumed it was pawls or something. Pawls look ok, cogs were loose, bearings were pretty loose. Feels good now, but I broke the 13t.

Sweet, thank you, that appears to be pastorbobnlnh suggested above, I've emailed him!

If you wanted to go new instead of fix (I believe in fix) I also have a Cyclone IRD (Interloc Racing Design) 7-speed freewheel. 13-28 tooth. Brand new never mounted in an intact box. I was going to post on Tue when I get back from the coast.

well, the E, S, and U cogs were for the New Winner, and as the drawing indicates, the E and S cogs were intended to fit on the last spot on the freewheel body. There's a chance that it might fit on the Alpha too. I'd have to measure the ID of a E or S cog to figure out how big it is.


https://cimg0.ibsrv.net/gimg/bikefor...824200f3e1.jpg

Steve in Peoria

If you're going to perform the "summon pastorbobnlnh" spell, do it properly. :)

Unfortunately, I don't think Mentions provides any notification unless the person checks the control panel option to receive a pm. You don't know if they did. And, for the recipient, it can be a pain to click in and out of the pm stuff each time.

Along with others indicating the gap-toothed 13T sprocket will last a long time, all yourself how often you'll actually use it. In my location (flatland Chicago area) I rarely get to the small sprocket.

I also have one of these that skips on the smallest sprocket. It is a strange feeling and doesn’t feel as though the chain is jumping. Per the post from the OP, I will check into this more for loose bearing adjustment.

https://www.bikeforums.net/classic-v...atability.html

https://www.bikeforums.net/bicycle-m...accushift.html

I was out at the local community theater last night and missed all this excitement.

I'll check my spares later this morning and get back to sspeed and the rest of the gang. I know I have a few spare Alpha freewheels that have been serviced and are ready to ship. As mentioned earlier, replacement sprockets are challenging to find. While I'm looking, I'll cross check to see if any other Suntour 13T fit the Alpha body.

I appreciate the offer! I also have one of those and it's too wide for this particular frame. I usually just do the <$20 Shimano freewheels, but even that is too wide for this frame.

One other option -- Ben's Cycles - Denver:

Vintage Suntour AP 7 Speed Freewheel - 13/24 - Used - $25

Fair point, we do an old bike group ride every Thursday so the small sprocket gets used a surprising amount.

I have this on hand; three used 14Ts, and one NOS 13T.
https://cimg3.ibsrv.net/gimg/bikefor...a975b1d571.jpg
BTW, Winner 13T will not fit on an Alpha body.