Frame Tolerance, Is This Acceptable?
Rack mounts aren’t the kind of thing I’d take critical measurements from. They should be reasonably straight, but I wouldn’t count on it. The critical measurement is whether the axle is perpendicular to the seat tube, and to measure that you either need a frame jig, or a straight wheel you can eyeball against the seat tube.Posted 5 years agojonbaMember
Don’t know if someone has already said this but is your wheel right?
Rear wheels are not symmetrical with respect to the flanges and need to be dished IIRC this means the rim sits closer to the drive side flange. This allows for the cassette on the driveside
If someone who built the wheel didn’t know this the rim will be symetrical to the flanges and look off centre when in the frame.
Do you have another wheel to try?Posted 5 years ago
Ok Cannondale have received the bike back and they say it was a problem with the dish of the wheel?! Despite me trying the wheel in the dropout both ways when i received the bike the which is the most obvious thing to try first, despite the wheel being swapped round the gap always remained the same 5mm less on the none drive side, ie there was is no fault with the dishing of the wheel, i didn’t measure the spokes (not that would matter anyway) but wouldn’t the wheel being on a single speed hub have the same size spokes both sides, making the wheel impossible to build with the dish that far out, maybe the spokes/hubs are A symetrical??? hmmm…
I thought i’d ask on here first before i sent the bike back, thanks to all those who responded, (i know a few of you) and appreciate the input from the experience bike builders on here, Tim, Brant etc. To put this into some kind of context I’m a qualified mechanic and used to prepare race cars and motorcycles for a living, so not really a numpty when it comes to what’s right and what wrong as far as engineering goes, i could maybe should have rigged something up to measure the bike before i sent it back (but why should i have too?) Just thought i’d ask on here in case i’d missed something obvious.
Anyway the outcome being they wont send me another frame i can have the original one back with the wheel dishing corrected?!
Anyway the saga continues…Posted 5 years agobrantSubscriber
You are correct in saying that if the wheel is swapped around and the offset remains on the same side, then there is an issue with stay alignment.
What I would say is that stay misalignment doesn’t automagically mean wheel misalignment along the frame.
I don’t understand why you’re discussing spoke lengths though. It doesn’t matter what the dish is… if the “wrongness” remains constant whichever way around the wheel is fitted, then the frame is out of track and the wheel is dished correctly.
This is what’s happening? Right?Posted 5 years agoJunkyardMember
What Brant said
but wouldn’t the wheel being on a single speed hub have the same size spokes both sides, making the wheel impossible to build with the dish that far out, maybe the spokes/hubs are A symetrical??? hmmm…
Technically you could build any wheel out of dish and nowing the spokes lengths wont help you know whether it is in dish or not
You can make a cardboard dishing tool ?
Cut some cardboard to make a square [ ie 90 degree] U that touches on the rime and measure to the hub – do the same on the other sidePosted 5 years ago
If its not equal then its out of dish – given you are its about mm this is only a rough guidejulianwilsonMember
I will add my voice to the many saying if you rule out too much paint inside the drive side dropout, (which would have been literally a two-minute check-and-fix for Cannondale CS), and the rim is skewed too far in the same direction whichever way round you put it in the frame then it is the frame which is at fault not the wheel.
This is shaping up to be some top PR for Cannondale Customer Services 😆Posted 5 years ago
Hi Brant, yeah the “wrongness remains constant”.
Obviously i first thought “the dish is out on the wheel!” swapping it round the “wrongness remained” ie wheel always remains 5mm closer to the non drive seatstay/chainstay, it doesn’t switch sides.
Maybe they’ve just “cold set” the frame to correct it ;).Posted 5 years agofibreMember
Surprised to see a new Cannondale like that, any decent LBS would have sent that straight back before it got to the customer. One of the hazards with buying online. Insist on a refund (or at least a replacement) and see if there’s any decent local deals, saves hassle in the long run.Posted 5 years agoBigJohnSubscriber
Hi Tim, yeah It’s Jon… the one who crashes into Klein’s at Cannock (now that back wheel did have dishing problem!), happy days!lol
Yes, but I fixed that wheel enough so we could all finish the Thursday night Sideways ride, didn’t I? And weren’t you on that carbon bike purple one side, yellow the other?
Still remember it, makes me laugh every time.Posted 5 years ago
Hi Tim and John 🙂 This is a bike i’ve bought for riding in the winter! so i might come out for a blast when i have time.
They sent me another bike last Tuesday with a frame that no longer has the problem, ie the wheel is now centred with regards to the seat tube and stays, cheers to all those who replied.Posted 5 years ago
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