whoops - reversed some cogs on my cassette
 

I think I accidentally reversed a couple cogs on my cassette when I replaced my rear wheel over the weekend on my commuter bike. By the time I can get home to fix it, it'll be around 20-21 miles ridden. 10-11 miles of it ridden without me realizing what I did wrong (and trying to use those cogs). I'm hoping I didn't ruin the cogs that were reversed... anyone know if I may have rounded out the teeth and/or chain with my screw up given the miles ridden? I feel like an dunce. When using the reversed cogs/sprockets, the derailleur wanted to shift to the harder gear (or maybe the other way around, don't remember).

With newer stuff thats not possible as there is a wide spine next to the narrow one,
flipping results in a No Go .. 'fit'.
you would have to go to a bike shop,
face the potential embarrassment, and ask some one who can SEE it.

since you expect text to work,
like the pictures not offered.. its probably accurate :rolleyes:

(OK you are at work and sneaking that note on the company computer)
don't get caught :lol:

Makes sense.

Then I wonder why the heck gears 5-7 (maybe it's 6-8?) want to shift off the gear? The other ones are just fine - smooth as can be! Shimano/SRAM freehub btw.

Check that overall spacing matches, and the cassette is tight. You can improvise a feeler gauge out of just about anything to confirm that there's not a mis-spaced sprocket anywhere along the line.

Also double check gear hanger alignment, especially if you had to adjust RD trim recently.

Possibly a bent derailleur hanger or loose cassette.
Or you may need to adjust the rear shift cable at the barrel adjuster. See www.parktools for adjustment instructions.

Wow - at work right now. I don't have a way to snap a picture. Just installed it over the weekend, so I wasn't aware of the malfunction that I created till I was on my way to work. Thought someone might have experience with something like this, and was simply thinking of things I may have done incorrectly.

Did you disassemble this cassette down to the loose cogs & spacers?
IF you did, I'd check for-
Debris caught between cogs & spacers
or
The spacers have some 'extrusions" on them from being compressed and not allowing the cogs to fit quite as closely together as they should.
This would have a cumulative effect, with each progressively smaller cog getting further out of place.
IF so, take a file and knock of the high spots.

I'd also look for a loose lock ring.

+1

Many cassettes have little knobs or splines so everything "fits" together as one solid piece when it's put together correctly. If these are sticking out the cassette will have the wrong spacing and it won't shift correctly. I imagine this is an attempt to make the cassette more rigid and spread out the load between the cogs so the freehub bodies don't get cut into. On steel Shimano Freehub bodies this is not an issue.

Edit: Hillrider is correct, Hyperglide cassettes cannot be mounted backwards. Only the old Uniglide cogs/freehubs had this ability.

If they were way older twist tooth cogs, maybe they would work flipped,
double the wear life, never owned any of those so its a guess..
they had symmetrical splines Way back then,
the cog on 3 speeds, if flat, can be flipped, Dished cog would change the chain line .

Rohloff designed their 1 cog to be flipped over.

You can not "reverse the cogs' on any Campy, SRAM or Shimano cassette by flipping them over since they are "keyed' and only fit one way so I assume you mean you put them together with a couple out of their numerical sequence. For example 12/13/14/17/15... rather than the correct 12/13/14/15/17... If that's the case, just reassemble the cassette in the proper order and no harm done.

The spec to tighten the cassette lockring is around 40 N-m or 30 ft-lb.

modern shimano ultraglide cassette cogs can be reversed on shimano uniglide cassette freehubs, i think. of course, shimano uniglide freehubs were discontinued more than two decades ago, but they are still out there, maybe on shelves, but out there.

i want to know more details about the type of cassette the OP has on there and the reason for fooling with it, not that i doubt his or her judgement.

Hyperglide cogs cannot be mounted on Uniglide-only Freehub bodies without grinding down one of the splines. You could go the other way if you wanted, but it wouldn't make much sense putting an old Uniglide cassette on a new body...

you are right, of course. i'm glad you reCOGnized my error. :twitchy:

The cassette is a standard run of the mill 9 speed Shimano Ultegra, or maybe 105, I dunno, forgot. I took it off of my old wheel, installed on new wheel, which is why I reason I was messing with it in the first place. That being said, I wonder if it has something to do with possibly my rear derailleur needing adjusted to the new rear wheel? I've never replaced a rear wheel before... I'll be working on the bike tonight sometime when/if I get a chance. The ride home, I realized it's bad in gears 5 through 8, not sure about 9 because I didn't get a good chance to use it, pretty tight cassette, 11-23.

there is your problem, new wheel. needs a rd adjustment

Yup. Hub dimensions are often a tiny bit different between brands.

Is it a Mavic hub?

Nope, not a mavic hub. It's a Fuzion wheel & hub. Dang it. I was 'fraid of that. Don't have the tool or knowhow to adjust the derailleur. Should be ok to use the bike still without hurting anything right? Just not gonna use the bad gears (5 through 8)? I wanna be able to commute still this week before I take it to the shop.

rear derailleur adjustment, or hanger adjustment?

Hanger adjustment not necessary unless you bent it since you put the different wheel on. Different wheel, different cassette position = minor cable adjustment and re-check the limit screws.

Only tools needed are your hands to twist the adjusting barrel on the RD and possibly a flathead or Phillips screwdriver for the limit screws. Careful with those screws though, if you do it wrong the chain can jump off into the spokes possibly destroying your rear wheel and RD all at once! Not fun.

Simple: tools are your fingers to tighten/loosen the barrel adjuster nut at the derailleur, or maybe inline adjuster near the shift lever. And the feedback tool is your ears. I'm guess you're only 3/4 of a twist away from spot-on.

As Bill K pointed out, Park Tool has an excellent website for repair and maintenance.

Bonus if you have a maintenance / repair stand, since it's best to pedal and adjust the nut simultaneously.

I should have known to try the nut on the derailleur. I guess I never would have thought simply replacing the rear wheel could throw it off just enough to change the jockey wheels in comparison to the freehub. Lesson learned. All gears are smooth as silk now.

Yep, amazing how often this is necessary. Last weekend my son-in-law called to say he had put a new rear wheel on his bike and had just transfered the old cassette and kept the chain and it was now skipping gears but it had shifted perfectly on the old wheel. Both wheels were built on standard Shimano 8/9/10-speed hubs so why the problem?

I told him to dicsonnect the rd cable and set up the rear shifting as if it were a brand new installation including setting the limit screws and cable adjustment. I got a call about 20 minutes later telling me that solved the problem and the bike was now shifting perfectly, just as it had been. It took small adjustments on both limit screws to compensate for the slight difference in hub dimensions.