HG 8-spped cassette: spacer or no spacer?
 

I have come into possession a Shimano 8-speed, 11-21 tooth (road) cassette. It's silver painted finish. It has 14-21 (5 cogs) pinned, and 13, 12, 11t cogs loose, plus a HG-C lockring. I found no typical spacer.
Looking on Shimano's tech doc site, yields no such cassette from them. Odd.

Has anyone come across such a beast? Am I missing a spacer or don't need one?
The 13t cog appears to made to clear the 3 pins of the main cassette body.

What do you mean by "typical spacer"? What spacer are you asking about?
All of the cogs should be equally spaced.
There is no need for a spacer behind the cassette unless you have a type of MAVIC hub designed to work with a MAVIC cassette. This type of hub would need a 2 mm spacer behind a Shimano cassette.

I'm referring to the ~1mm spacer that seats between the main cassette sandwich and the first loose cog. In my case, 5 cogs are pinned, followed by 3 loose cogs then lockring.

You need whatever it takes to make the cogs equally spaced.

I know the spacer you're talking about. I think it's used with 14-tooth and larger cogs with built-in spacers, so your 13 would not need it. I agree with Al- measure the overall thickness of the cogs. If they're all equal, put the cassette on the wheel and go ride.

FWIW: if you get tired of looking at it, I'll take it off your hands. I have a need (OK- I have a weird bike parts fetish) for an 8-speed 11-21 cassette.

That's why I'm asking the question here....to see if the collective has come across such cassette. As I initially posted, there is no reference schematic to this Shimano model on their web site. There is a lot of variance to their 8 speed cassette offerings.

[edit]
Thanks Jeff! At the moment, I don't have a spare freehub handy to mount it and bust out the machine's rule.
I'll try to make do on a flat surface and see if the spacing is in this 13t cog.
Oh, and yes, I too need this 8 spd road cassette, was very happy to discover an 11-21, roads are almost billiard table flat here. ;)

I thimpk that it's from an early '90's Ultegra setup. Certainly Shimano's current 8-speed offerings are not as extensive as back then.

Silver painted? Are you sure? Not plating or similar finish?

Sheldon doesn't list this cassette but I beleive there was a Dura-Ace 7400 with this setup. (Since this is HG that would probably be 7402.)

The stack appears to be silver paint or powder, and the 3 loose cogs are chromed. No drilled holes to the larger cogs.

AFAIK, 2 Different freehubs .. thread on the small cog, is one , lock ring is another..

Generally speaking, Shimano Hyper-Glide cassettes with the two higher gears separate from the cluster have 'built-in' spacing.
i.e. the cog has a machined section which provides the spacing.

The easiest way to check this is just hold the cassette, with the two cogs in place and it will be obvious if there is a spacing issue.

Regards,
Roger

I have had 7 and 8-speed cassettes that came with a thin (1mm) "scalloped" spacer that goes under the smallest cog. Some come with it and others do not.

I don't know if it's standard on some configurations and not on others or if it's included with some cassettes to adjust for manufacturing tolerances.

Ooohhh... that may be a combination of different sets. Matte silver finish was typical of Ultegra and below, chrome was Dura-Ace. Drilled cogs didn't come along until early in the Aughts, I think.

Nevertheless, if the cogs are loose, it's easy to tell if one has a thinner spacer than the other. Flip one over and hold them next to each other so the cog portion is on top of the spacer portion of the other. You'll be able to easily see if the spacers are different thicknesses.

BTW: nice sig line. It sounds like my job.