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Discussion Starter · #1 ·
I have a pair of 6 months old fulcrum racing 5 db wheels that have had their issues but do the job and are quite light. I've been running them on a specialized diverge and apart from bearings and a slight buckle they've been fine. I then took delivery of a Trek emonda alr5 db and swapped out the stock wheels for these, instant weight saving, took the bike up the road, all gears and brakes working just fine. Later in the day I just happen to notice that the rear wheel is sitting around 3mm too far to the drive side. I checked everything on the bike, fine, and then checked the wheel dish using the food tins under the rim and stacking coins until they reach the hub approach. This revealed the dishing to be way out from side to side (never noticed on the diverge!), do I had my lbs adjust it and now it's better but not perfect.

Had anyone else experienced this? Are rear wheels meant to be identical each side for dishing, it is it something to do with Trek and their frames?

I'd like to get it perfect if possible.

Many thanks.
 

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I never heard of whatever method you mentioned regarding checking wheel dish. I use a dishing tool.

ALL wheels should be centered between the axle ends (dished) correctly.

It's easy to get dish within fractions of a millimeter.

If you're wheels are correctly dished and yet they're still offset in the frame, then there's an issue with the frame.

First check that there is no paint build-up in the dropouts which would cause the wheel to sit crooked.

Rotate the axle with your fingers and verify it's not bent.

If the same wheel looks good in one frame but not another, then the odd frame is at fault; there should be a symmetrical gap between the tire and the chainstays and seatstays.
 

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Flip the wheel in the frame. That will tell you very quickly if the problem is with the wheel or the frame. As previously stated, be it front or rear wheel, the rim should be perfectly centered to that of the axle.
 

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It is measuring time (or more measuring....), in no specific order:
  • Double, triple..... check that the wheel is sitting correctly in the drop outs.
  • Make sure both (everything, frames wheels....) are the same drop-out spacing wise (and one is not 130mm and the other 135mm). ~3mm sets off some spidey sense here. Maybe also double check the specs of everything in this respect as well. Compare measurements to specs.
  • Like RHankey said put the wheel in backwards to see what happens. If the frame is straight the offset should shift to the other side by the same amount.
  • IF the frame looks to be out (based on above) you can use the string and ruler method to check the frame(s), not as good as fancy frame tools but....
  • Check drop out alignment, two lengths of 3/8" threaded rod or long 3/8" bolts hand full of nuts and washers can be used. Again no need for fancy tools.
  • The way you measured dish works fine, no need for fancy tools here but check it again... both wheels.
Assuming some or all of this is used??? maybe one or more things are/were out and someone in their infinite wisdom made some goofy adjustments... You have covered some of this but check it all, double check....it is best to know 100% for sure before making any adjustments yourself, or asking a LBS to adjust (avoid chasing your tail).
 

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I never heard of whatever method you mentioned regarding checking wheel dish. I use a dishing tool.

ALL wheels should be centered between the axle ends (dished) correctly.
^^^This. A wheel should not be dished to compensate for a bike frame. That may be the design of that frame. Unless you have tire rub, this is a non-issue.
 
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Discussion Starter · #6 ·
^^^This. A wheel should not be dished to compensate for a bike frame. That may be the design of that frame. Unless you have tire rub, this is a non-issue.
Thanks for all the replies, really useful. So far, of all the things to check, I checked the dish of the wheel the bike came with, that's marginally out too (by about 0.5mm) and also sits a little too far (in my mind!) to the drive side. Put my fulcrum wheel back in and suddenly it doesn't look so bad.

I will check the other items you mention and report back.
 

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Well, I've built wheels 'perfectly' that acquired dish a short time later (I'm not a pro).
If you take your wheel out, flip it the other way, you'll be able to tell if the wheel has dish, or if it remains in its condition because the frame is bent.
If it's the wheel, it requires some more work.
 

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The rear wheel almost always needs to be dished to fit the big cassettes people use these days. Sometimes looking at the rim in relation to the frame isn’t a good indication of how dished it should be and it need not be centered in relation to the seat and chain stays yet still right and in-line with the front wheel.
 

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First of all, your measuring setup sounds suspect. If you have access to a machinist's inspection plate and a set of matched machinist's points, then used a set of measuring blocks, I'd believe your 3mm number. But if all you are using is a bunch of coffee cans on a table (resting on the rim, not the tire), you have just introduced significant measurement error.
 

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The rear wheel almost always needs to be dished to fit the big cassettes people use these days.
Wheels have been dished since a cog was added to the right side unless the left side flange was artificially forced to the right to eliminate dish (a fundamentally bad idea that reappears every 20 years or so). Dishing has nothing to do with "the big cassettes people use these days" and everything to do with where the hub flanges are relative to the end nuts on the axle.
 

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Dishing has nothing to do with "the big cassettes people use these days" and everything to do with where the hub flanges are relative to the end nuts on the axle
Saying dishing has nothing to do with needing room for a cassette and just to do with spacing the flanges equally, is like saying fat people need to pull their seat back more from the table not to make room for their belly but get their fork and knife at a good distance.
 

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Wow tough crowd. Okay, dish is a result of needing to center the wheel on the axle of the rear hub. This effectively centers the rim with the frame as well. It’s true that this is because any cassette system would require dishing. Even the old 5 speed hub free wheels required dishing. Drive side spokes are generally 2 mm shorter than non drive sides and the angle of the drive side is steeper than the non-drive side. There are some offset rims such as a Velocity Aero Head rim that have the rim holes offset away from the drive side a few mm or so to reduce the amount of dish angle. I have built up these for my bike. There is still dish present just less drastic. The front rim is standard shape and not offset. To check your dish flip it over in the truing rack and check to insure the rim is centered both ways. If so your dish is correct. If for some strange reason there is an offset when you install it make sure there are no extra washers or shims on your axle. You could have a bent frame or it may have been incorrectly cold set to the 130mm if it was the previous narrower width frame.
 

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The rear wheel almost always needs to be dished to fit the big cassettes people use these days. Sometimes looking at the rim in relation to the frame isn’t a good indication of how dished it should be and it need not be centered in relation to the seat and chain stays yet still right and in-line with the front wheel.
It has nothing to do w/ 'big' cassettes. It has to do w/ how much space the cassette takes up and the hub flange geometry.
Wow tough crowd. Okay, dish is a result of needing to center the wheel on the axle of the rear hub. This effectively centers the rim with the frame as well. It’s true that this is because any cassette system would require dishing. Even the old 5 speed hub free wheels required dishing. Drive side spokes are generally 2 mm shorter than non drive sides and the angle of the drive side is steeper than the non-drive side. There are some offset rims such as a Velocity Aero Head rim that have the rim holes offset away from the drive side a few mm or so to reduce the amount of dish angle. I have built up these for my bike. There is still dish present just less drastic. The front rim is standard shape and not offset. To check your dish flip it over in the truing rack and check to insure the rim is centered both ways. If so your dish is correct. If for some strange reason there is an offset when you install it make sure there are no extra washers or shims on your axle. You could have a bent frame or it may have been incorrectly cold set to the 130mm if it was the previous narrower width frame.
All good info.
 

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I’m surprised I wasn’t asked to provide references for that. Lol I know it wasn’t you but some users here are a little nuts
 

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I’m surprised I wasn’t asked to provide references for that. Lol I know it wasn’t you but some users here are a little nuts
You were only asked to provide a source when your information was questionable.
 
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