Bicycle Mechanics - Identifying speed of assorted cogs

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iain.dalton
09-28-08, 03:13 PM
A bunch of loose cogs have come into my possession. How can I identify their speed so I can maybe upgrade some of my bikes and sell the rest (or see if I can get credit for them at my LBS)? I have:

2 16t
4 15t
4 14t
3 13t
1 14t (with spacer)
1 13t (with spacer)
5 12t (with spacer)
1 11t (with spacer)
1 18-21-24-28-32
2 21-24-27
1 21-23-25
1 21-23
3 17-19
5 9-speed spacer rings
3 10-speed spacer rings
1 small fat spacer (not sure the purpose)
2 lockrings

A related question: does anyone have any experience selling a bunch of individually cheap bike parts online? What's the best way to do it? Sell the whole thing as a grab bag?


Ex Pres
09-28-08, 03:31 PM
You'll need an accurate caliper and compare them to this (http://sheldonbrown.com/k7.html#spacing) chart.

operator
09-28-08, 04:10 PM
A bunch of loose cogs have come into my possession. How can I identify their speed so I can maybe upgrade some of my bikes and sell the rest (or see if I can get credit for them at my LBS)? I have:

2 16t
4 15t
4 14t
3 13t
1 14t (with spacer)
1 13t (with spacer)
5 12t (with spacer)
1 11t (with spacer)
1 18-21-24-28-32
2 21-24-27
1 21-23-25
1 21-23
3 17-19
5 9-speed spacer rings
3 10-speed spacer rings
1 small fat spacer (not sure the purpose)
2 lockrings

A related question: does anyone have any experience selling a bunch of individually cheap bike parts online? What's the best way to do it? Sell the whole thing as a grab bag?

The I.D of 7/8/9/10 speed chains are all 3/32.


iain.dalton
09-28-08, 04:22 PM
I don't have accurate calipers, and a Froogle search seems to indicate that calipers that can detect the difference between an 8-speed and a 9-speed would cost a lot. If they're so close in width, is mixing allowed?

Also, is diameter the right word for the distance between the inside faces of two plates on a chain?

Bill Kapaun
09-28-08, 05:45 PM
I've used a couople "wrong size" cogs in my "custom cassettes" wothout issue.
I'm not sure if I totally agree with that chart though. I made up an 8 speed cassette, using 7 speed cogs. I had to thin my spacers to about 2.75MM.

HillRider
09-28-08, 06:39 PM
I have:
1 14t (with spacer)
1 13t (with spacer)
5 12t (with spacer)
1 11t (with spacer)

I believe you mean the cog and spacer are all one piece. These are all first position cogs but could be from any speed from 7 to 10.



1 18-21-24-28-32
2 21-24-27
1 21-23-25

The 18x32 is almost certainly a 9-speed and came from an MTB cassette. The 21x25 and 21x27 can be either 9-speed or 10-speed.



1 small fat spacer (not sure the purpose)
This is probably a 4.5 mm spacer to allow a 7-speed cassette to be in stalled on an 8/9/10-speed freehub body.

As mentioned,you need to buy or borrow a good caliper or, better yet, a micrometer.

iain.dalton
09-28-08, 06:57 PM
I wikipedia'd 'micrometer' and wow, what an ingenious design. I still would rather not buy one since I can't foresee any further use for it, so I'll try the grab bag approach.

Jeff Wills
09-28-08, 10:27 PM
Shimano cogs are typically marked with their "Code". Look for one or two letters near the inside diameter. It should be a single capital (i.e. "K") or two lowercase (i.e. "ab"). Then refer to the Shimano combinations at http://www.sheldonbrown.com/k7.html . This should give you a start.

Shimano says you can't mix cogs with different Codes. In practice, it's rarely a problem. Mix, match, slice, dice, julienne! (Maryanne or Ginger?)

iain.dalton
09-29-08, 11:29 AM
I'm finding codes not in those tables:

XC-XC-WL
ZF-ZI-ZI
YF-YF-YF
CK-CK (the two-cog ones also have text not on the face, but near
the inner ring, in this case, 21-23 DA)
YE-YE (17-19 YH)

And so on.

I did identify the cluster of 5 cogs. It says "Q·R", "18t", "YG",
"4", and "P" on the smallest (18t) cog. P is the name of the 12-32
8-speed cassette, but I can't decode the rest. The inner ring says,
"SHIMANO / CS-M900 / Y 3 TYPE-P / JAPAN".

Bill Kapaun
09-29-08, 11:41 AM
Shimano cogs are typically marked with their "Code". Look for one or two letters near the inside diameter. It should be a single capital (i.e. "K") or two lowercase (i.e. "ab"). Then refer to the Shimano combinations at http://www.sheldonbrown.com/k7.html . This should give you a start.

Shimano says you can't mix cogs with different Codes. In practice, it's rarely a problem. Mix, match, slice, dice, julienne! (Maryanne or Ginger?)

Good point about the CODES!

I also agree that mixing isn't a problem, at least not for me.
I've mixed an-
"E", 12-14-16-18-21-24-28 and an
"H", 13-15-17-19-21-23-26 to make a
13-14-15-16-17-19-21-24. (thinned spacers & 8 speed FH body))
Maybe the 1T increments help?

iain.dalton
09-29-08, 12:06 PM
The only problem, as far as I understand it, with mixing codes, is that ramps and pins are designed to allow a smooth transition to the next cog, and if that cog is the wrong one, the transition won't be as smooth. This is hardly a problem, as cogs got along fine for decades without any ramps or pins at all.

Does anyone have any ideas what the codes I found mean? I only listed codes found on clusters, but the single cogs have them too, saying "ZI", "DD", "DB", et al. There are codes all over bikes, and sites explaining many of them, but I can't find any info on them.