goose70

Now that I have multiple wheel sets, I’m having difficulty properly adjusting my rear derailleur as I change sets from day to day. I have an Ultegra 6700 and understand that the top screw adjusts the outer limit of the derailleur and the bottom screw adjusts the inner limit. Still, I cannot get the thing to travel just right through the shifting (skipped gears, etc.).

As a threshold matter, after I make adjustments by eyeballing the derailleur position on the cassette according to the Shimano literature, I cannot figure out how to fix some of the shifting problems that remain. For example, it often shifts fine on the way in (going from small to large sprocket), but then skips on the way out. Is that a lower or upper screw adjustment? Am I missing any simple tricks to this?

The LBS told me that my wheel sets are close enough that only minor screw adjustments are necessary during the change, but they’ve been too crowded the last couple of times to show me. I’m thinking that once I get it right the first time, I’ll be able to simply remember how many screw turns it took to switch from one wheel to the other and make the adjustment in seconds.

Thanks for any tips.

LowCel 

Are you adjusting the cable as well or juts the limit screws? It sounds like the cable is going to need a slight adjustment as well.

I've always been lucky I guess, all of my wheels have always been compatible so no need to make adjustments.

zatopek

The derailleur inward and outward travel limit screws will only define those parameters. To microadjust the position of the derailleur jockey wheel relative to a given cog, use either the RD barrel adjuster or the barrel adjuster on the down tube where the RD shift cable enters. Put the bike on a work stand, continuously turn the crank and shift up and down the cogs. When you get to a place where it does not shift smoothly, keep cranking and adjust the barrel adjuster until the noise quiets. Do this until you can go up and down the cassette smoothly. If you try and try but can't dial it in, might be time for a new cassette and/or chain, if they are excessively worn.

rbart4506

You should only have to make a barrel adjustment to cable tension to make things work...

The limit screws only affect how far the derailleur will travel outwards or inwards...Not what it does in between...

ooops...Too slow...

goose70

Thanks. The cassetts on both wheels are new this spring, as is the chain, so the barrel adjuster sounds like the way to go. I'll give it a try.

deacon mark

Get the chain on the big ring and the smallest rear cog. When this is adjusted so the limit is correct and the chain will not go father than the small cog, dial it in so there is no noise. Then without using the brifters tighten the barrel adjustment till it starts to go to the next cog as if it was going to shift. Then once you get to the point that this makes it shift back, off the barrel adjuster till the gear is perfectly in tune and not noise. Now you should be pretty close if not right on in each gear. Start using the brifter and go up in deliberate shifts of the same power stroke. This should be clean in all gears but if you get to a noisy one then use the barrel adjuster to tune that particular gear.

Sometimes you can really pop the brifter hard and it will actually jump two gears that is possible. In any case if you must start on the big ring in front and small cog at the rear and move from that point.

dstrong 

It's possible that the dish on the two wheels is not exactly the same...so the in-to-out range on one doesn't match the in-to-out range on the other. That might explain the poor shifting also. I would either check the dish of both wheels myself or take both rear wheels to your LBS and have them check it. If you're not comfortable changing the dish (if needed) go the LBS route.

svtmike

dstrong, how will the dish affect it? if a wheel is dished incorrectly, it wouldn't be aligned with the frame, but that shouldn't change the position of the cassette relative to the derailleur.

deacon mark

The dish as mentioned only effects the wheel in the frame the rear sits the same regardless.

digibud

I would definitely get some help from your LBS. I don't know why two wheel sets can't be setup so there is no issue when swapping them. I have two wheel sets for a pugsley which means both front and rear are dished and it took some careful shimming to ensure swapping would result in the brake rotors remaining in perfect alignment. If it can be done on a pugs it can be done for your wheels and you should do it. If it can't be done you should consider matching your hubs. Having to adjust the high and low stops would be crazy and dangerous to boot given the eventual odds of making a mistake and throwing a chain. If all that is needed is a barrel turn for more accurate shifting that might be not such a big deal but if both wheels are dished the same that shouldn't be necessary either.

dstrong 

Dang...you guys are right...I was thinking about how one cassette on one wheel would end up in a slightly different place that the cassette from the other wheel...but dish won't matter. What about differences in hubs? Or spacers on one cassette and not on the other.

As another trouble shooting idea...I would put each wheel is in place, then put a ruler against the same cog and measure the distance to the chainstay...again...just to make sure there isn't something inherently different about where the cassette sits in the driveline.

svtmike

I've had really good luck swapping hubs on my bikes -- I have used Specialized Roval, Neuvation, and a couple kinds of Powertap pretty much interchangeably with 6600 and 6700 cassettes among my bikes. The only time I've had poor shifting was when I had the stock SRAM cassette on my Specialized wheelset instead of a Shimano cassette.

sffred

if your drivetrain stays within the same cassette count(ex:9speed or 10speed) and your wheelsets have different gearing the only thing you should adjust is the B-TENSIONER screw and if necessary the barrel adjustment.

the B-TENSIONER screw will help alot! it actually helps keep the chain in the correct gear while in chain flex!

but you may want to start fresh and adjust your limits properly! youtube is you best bet!

note: if your wheelsets have different hub body(s) if you are running a 10speed on a 9 speed hub you will NEED that 10speed spacer!

Jed19

I run seven wheelsets, and the only thing I have had to adjust are the barrel adjusters. My cassettes are 12-25 and 12-27s.

As zatopek mentioned in post #3, get the bike on a stand, crank and shift the rear one sprocket at a time, when there is some hesitation in shift, turn the barrel adjuster towards the hesitation (if not moving crisply to the bigger sprocket, turn adjuster in small turns towards that sprocket until it shifts crisply).

Of course, my cassettes are all 10-Speeds.

dstrong 

Let's see...are they labeled "Monday", "Tuesday", "Wednesday"...

rdtompki

With your "standard" wheel mounted have you adjust the RD and cable tension following either the Park Tools or Sheldon Brown directions? There really shouldn't be any eyeball assessment involved.

Jed19

No. I have just ended up with seven wheelsets by chance. Some came with bikes that I sold piecemeal while keeping the wheelset.

abstractform20

it could be a lot of different things. it could be derailleur hanger issues, cable tensions issues, limit screw issues, a combination of all, chain issues, etc. one thing is certain: you do not know what you are doing.

sheldonbrown.com

google.com

youtube.com

bike mechanics section of this website.

et. al.

popeye

If as you say it shifts fine to the larger diameter cogs you need to replace the cable and housing. When changing wheels align the derailer to the center cogs and you should be withing a half turn of the barrel adjuster.

goose70

Thanks for the replies. Popeye wins. Mostly.

After spending 45 minutes with my LBS bike mechanic, I learned that I was doing it mostly correct. The fundamental problem was a kinked shifter cable that he had to replace. The two wheel sets (Soul S3.0 and Shimano RS20) simply have the cassett in slightly different positions relative to the RD, so a 3/4 turn on the lower and upper adjustment screws will be necessary each time I switch out. A slight barrel adjuster change is alo necessary, so the whole process is a mild inconvenience at worst.

I want to put in a good word for my LBS, Bike Doctor of Arnold, Maryland. This is not the first time they have gone above and beyond for me, but last evening took the cake. The mechanic spent 45-minutes with me going over every detail, changing the cables, switching wheels multiple times until we had the exact adjustments dialed in and written down. He refused to accept any money from me for all of this. If you live in or visit the Annapolis-area, I highly recommend this place.