I just got a set of Zipp 808 (2008) and speced it with a Shimano Ultegra cassette (11-23), including the 10-speed spacer. The Zipps are going to be my race weels in 2009 so I did not ride them yet. But even when I tested the gears on the work stand I noticed the following: The cassette on the Zipp is situated significantly more to the left than the cassette on my every day wheels (Shimano WHR-550). Thus each time I shift to the 11 tooth ring, the chain falls from the cassette and in between the cassette and the frame.
The obvious solution would be to adjust the whole drive train every time I use the Zipps. In a way I am reluctant to accept this fact because in 20 years of building up bikes myself this has never happened. Rear wheels were always interchangeable without this hassle. Especially replacing my WHR-500 with the old race wheels (Mavic cosmic Carbone) was always without any problems.
What I’d like to know:
Is this a known problem of Zipp hubs/wheels or did I screw up somehow?
I have not had the issue with Zipp…really…but I always did need to twist the barrel 1/2 turn or so one way or the other for the Zipps in my fleet. Now, my PowerTap on the other hand going from Shimano / Campy required re-dishing for some freaky reason (Saris was no help…I always thought center was center). If it is only a twist or two I would call it the cost of race prep and call it a cay. More than that - time to start taking things apart and asking questions…oh, is dish off?
“Dish” is the center of the wheel being in the center of the bike (or as most folks know) brakes. If you put in one wheel and your brake and gears are set, and another your gears AND brake are off to one side, that would mean that your wheel “dish” is off. Rear wheels with spokes that are shorter on drive side than non-drive (damn near every rear) will have a “Dish” where if you look at it from the edge, one set of spokes have an angle greater than the other (drive side steeper or not even visible).
For my PowerTap the Campy “dish” for some freaking reason was 3mm off of Shimano…no other wheel in my thousands have been that way. But alas, only my PowerTap has needed more than just a freehub change for a cogset change.
I have no idea if this is a common issue for Zipps or not, BUT I would not correct it with the barrel adjuster, the correction should be made with the limit screws. You will have to adjust your high and low limits when you change wheels. The barrel adjuster is just for indexing correction- if your shifts are hesitating.
I am quite confident that I could adjust the shifting correctly if I used the limit screws each and every time I change from every day to race wheels and back. This really would going to be quite a hassle.
In another forum I was told to try and put a spacer under the cassette in order to bring it a bit more to the right. Comments?
In another forum I was told to try and put a spacer under the cassette in order to bring it a bit more to the right. Comments?
I’m like you in that I’ve put different wheels and different cassettes in and out of my bikes thousands of times over the years. A half a turn to the barrel adjuster might be needed sometimes, but that’s about it. Given what you paid for that wheel, you shouldn’t have to be coming up with solutions like adding spacers. It sounds like there’s a larger problem and Zipp needs to address it for you. Call them – or the dealer who sold you the wheel. I’ve worked with Zipp in the past on some issues and they’ve been very fair.
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Well… calling Zipp/the dealer should be the obvious thing to which I#ll do this afternoon.
The only problem is that I bought the wheels from a UK based bike shop (wiggle.co.uk) and had them shipped over here to Germany. So stopping by and have the seller have a look at the wheel is not much of an alternative.
You could put a small washer on the right side of your WHR-500’s to space it to the left slightly, then adjust the limit screws to work with both wheels.
Hmmm… Somwhow I I am reluctant to screw around with the all Shimano hub, free wheel and cassette. I rather think there is something not right with the Zipps.
I have a 2008 PT 808 and have no issues swapping back and forth. I have a spacer on the inside of my other wheels but not on the zipp IIRC. I have a sram cassette on it if that makes any difference.
You find the answer I got from the seller in the UK today below. Should I be satisfied and just live with the issue?
“Thank you for your email. Sorry to hear of the inconvenience caused whilst changing your wheels. Fortunately it is unlikely that there is anything wrong with your wheel, unfortunately there isn’t any thing I can do to stop you needing to adjust your gears every time you change your wheel over. The Zipp wheels are very aerodynamic so there is a chance that they have been taken very slightly over to the left during the design of the wheels but essentially you have been very lucky to have not come across this problem in the past. Most wheels are spaced slightly differently on the axle and will give a different chain line but as you pointed out you can usually adjust this out at the lever, in this case it could be that your current wheels are on the upper limit of the right spacing and the Zipp wheels are spaced left, this would give the impression that there is a spacing issue. Sorry for the inconvenience caused, if you wish to have the wheels checked against the alignment of your frame a local bike shop can do this with a frame alignment tool. Thank you”
I would take the cassettes off of both wheels and compare the add’l 10 speed spacers on each wheel. Perhaps there is more than one spacer on the training wheel. I don’t see any problem with adding a few more spacers(thin) spacers to Zipp wheel to bring the cassette out slightly, assuming the lock-ring is still grabbing enough threads to tighten down the cassette.
I would take it to a good local shop and have someone look at it.
That’s the problem: No LBS around here in Germany knows anything about Zipp whela. And: Usually I would call myself the good LBS!
Would be suprised if it is a zipp issue. If so I am sure they will deal with it for you. I just suggested taking it into a shop to make sure that it is not something that can be dealt with by adding or taking away spacers on one or both wheels. Seems like the next step to me, could be totally wrong.
