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Frog Whisperer
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Discussion Starter · #1 ·
I did not want to hijack the other thread regarding rear alignment so I'll ask my own. Can a new carbon frame (with glued in rear dropouts...alloy) be aligned at all?

When I let my rear wheel slide in all the way, it is a tad closer to one side than the other. (both on the seat stay and chainstay, non-drive side) I have just been holding the wheel straight then clamping it tight. It holds fine and seems to ride and handle fine (both no hands and higher speeds) I have not had the bike over 40 mph yet and am wondering if it might be an issue.
 

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Old Skool
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What are the dropouts made of?

Most modern bikes have vertical dropouts. These are not adjustable except by grinding them. If the dropouts are metal, I would consider carefully determining if the frame is truly out of alignment and then using a dremel (or similar tool) to grind the dropouts as required to bring the wheel into exact alignment. This is not a perfect solution as once ground the dropouts will fit the axle loosely and the wheel will need to be hand aligned each time it it is inserted. If the bike rides straight and handles fine, my advice would be to leave it alone. If it is not broken (from an actual performance perspective) do not fix it.

If the dropouts are carbon, I differ to more expert opinion as to whether they can be safely ground and the best way to do this.
 

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Frog Whisperer
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Discussion Starter · #3 ·
dropouts are glued in and alloy (aluminum)

I am "hand aligning" them now, so I might as well leave it alone.
Although I fee pretty certain that I could accurately extend the drive side slot back the correct distance (MAYBE a mm) That may play havoc with rear shifting.
My thought was to "shim" the non drive side with JB weld.

OR I could leave it alone...I was just wondering if there was alignment possible
 

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I would suggest that you check your wheel for centering first. A simple but effective method is to simply put it in backwards. If it reverses the situation your problem is small and you need only have your wheel properly trued. If it isn't wheel centering you need to take your frame to the dealer of that brand and have them replace it. There's no way a shop can properly and effectively align a carbon frame for a rear triangle that is out of alignment. Maybe, just maybe a derraileur hanger, but seldom does that even work that well.

Good luck,
Bob
 

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Lambretta
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133 Posts
The shop I bought my roadie from simply filed the dropouts to allign the wheel in the frame because the tyre was rubbing through the carbon when I put the power down.

The problem now is that when I sprint or put the hammer down the wheel slips back into its original position and the wheel still grinds into the stay.

The shop has agreed to give me a new bike, although money back would the best bet for me right now with a new bike on the way.

I`ll not be buying from either my lbs or carbon frames, anymore.
 

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TheHeadlessThompsonGunner
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523 Posts
Touch0Gray said:
I did not want to hijack the other thread regarding rear alignment so I'll ask my own. Can a new carbon frame (with glued in rear dropouts...alloy) be aligned at all?
Yeah, for sure. But this is wheel alignment, rather than frame alignment, which usually involves bending and (obviously) can't really be done.

Problem is, it take some practice. Get a fat rat-tail file (9 mm or 3/8") and a fairly accurate pair of calipers that will allow you to measure from the outside, inside, or centerline - whichever is clearest, but be consistent - of the stays. With the bike upside-down (e.g., with the BB shell in a vise), drop a dead-nuts true and in-dish wheel in and figure out (by measuring, as above) which way the AXLE needs to move relative to the dropout for the RIM to move relative to the stay in question; unless you've had some practice or are very geometrically inclined, do ONE set of stays at the time (i.e., first chainstays, "horizontally," and then seatstays, "vertically"). It's hard to describe, but picture a right triangle from the centerline to the rim and dropout (i.e., with a highly acute angle at the rim end). If you move the axle, you move the rim. File away some material accordingly, bearing in mind that because of the shape of this "triangle," a small movement at the axle will result in a large movement, relatively speaking, at the rim/stay. In other words, GO SLOW. You can correct too much filing on one side with a little more on the other, but don't rely too much on this, because eventually you're going to have some pretty wonky dropouts.

As I say above, this take some practice. I've done hundreds - maybe thousands - of these, most of them Ti, and even with the hardness of Ti (and resultant slowness of the whole process), every so often I could still come pretty close to having to scrap a rear end from going too far...

Having said all that, one of the best tests for frame alignment is just riding the bike, especially without hands. If it tracks a line even just fairly well, it's pretty damn near to in alignment, which isn't all that hard to do when building a bike. Basically the only reason for you to perform all this, it sounds, is for aesthetics. But if it's going to bug you every time you look down at your rear wheel, this is as good a reason as any...

Lastly, this method of alignment assumes a very high degree of symmetricity between the centerline of the bike and the stays (and wherever you're measuring from on the stays). This may or may not be present in your frame, and the only way to be sure would be to check it on an alignment table. Obviously, alignment is best all performed at once.

edit: as another post above says, this can result in an oversized dropout that allows the wheel to slip. This is another issue that practice absolves: it is possible to file the dropout in all sorts of directions and still have a place where the wheel falls at rest and "under power" (the issue of good QRs not withstanding...), but knowing how to preserve this requires at least some very good geometrical aptitutde, if not just lots of practice.

edit two: DON'T use a Dremel. It's too small and its RPMs are far too high. At most, use a burr bit in a drill that has a cutting edge (rather than just abrades). But really, a good rat-tail file is your best bet.
 

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Frog Whisperer
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Discussion Starter · #7 ·
Thanks guys.....actually indyfan nailed it first. I flip-flopped my wheel and the error was on the other side! DOH........I am sharing wheels with my Bianchi and there is enough clearance that I never noticed it. I stuck it back on and sure enough....it isn't centered there either. In an attempt to see if the whole thing could be shifted via the axle (yeah I know now....) I ended up SERVICING my freehub AFTER I found the springs and pawls....looking back at that one....uh...not such a good idea although it was spotless and re-greased when I was finished. While I had it apart I put my new cassette on it and swapped the wheels back to the Bianchi until I can get the wheel taken care of. Sheesh, who'd a thunk it. It is absolutely true and round....I never suspected it was dished wrong! It has been like that for 6 years! I had taken the bike in for a "truing" a few weeks after I got it and the spokes kept breaking on the guy so he TOTALLY rebuilt the wheel.....too bad, it has been dead on since then WITH THE EXCEPTION OF THE DISH being off...

Now I know, thanks again

Oh, btw Applesauce, I wouldn't use a dremel, in my line of work I have WAY better (foredom flexshafts with electronic feedback control pedals) I can slow the rpm to a couple a minute if I choose and maintain power and torque....that along with dozens of cutting burs that are exactly the right size. (as well as dozens of small files) But I do appreciate the warning as will anyone who is reading this thread on a search to deal with a similar problem!!!!!!!
 

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Frog Whisperer
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Discussion Starter · #8 ·
update

I was going to try to re-dish the wheel, borrowed a buddies truing stand and on close examination found the dish to be EXACTLY 1 cm off!

I looked very carefully and noticed there were some "micro" cracks forming around the nipple holes so I took it in for a rebuild. New rim, nipples and spokes....(old nipples were rusty and steel)

I's done but it is pouring and I have other stuff to do so I'll probably pick it up tomorrow or monday
 

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Say what?!

Touch0Gray said:
I was going to try to re-dish the wheel, borrowed a buddies truing stand and on close examination found the dish to be EXACTLY 1 cm off!
That is a HUGE error. Find out who built/trued those wheels and have them taken out back and shot. Or at least never let them build wheels for you again.
 

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Frog Whisperer
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Discussion Starter · #10 ·
Kerry Irons said:
That is a HUGE error. Find out who built/trued those wheels and have them taken out back and shot. Or at least never let them build wheels for you again.
Absolutely, a HUGE error, no question about it. I am pretty sure those wheels haven't been TOUCHED since 2003 if at all....I know the original wheel was bad and the LBS replaced it with a "warranty" I do know they pulled it off another Bianchi but whether it was a "factory defect" or human error, I have no idea. I did have a wheel trued and 2 spokes replace a couple of years back but I am pretty sure that was the front not the back...but I suppose could be wrong about that.

The new wheel (old hub) was hand built by someone I trust.

Funny thing, I have NEVER been able to ride the Bianchi with no hands, I figured "meh...so what" BUT I wonder if any of it had to do with the fact that the rear wheel was tracking 1 cm to the left of the font?

Had I not been sharing wheels with my new frame, I may never have even realized the wheel was so far off...The tolerances are SO much closer and the stays much straighter.
 

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Frog Whisperer
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Discussion Starter · #11 ·
finished

wheel is home, cassette back on, everything adjusted and I gotta say the wheel is DEAD NUTS ON.......The wheel is truer than the tire that's for sure!

Thanks again guys....problem solved!

NOW it can stop raining and clear up...mkay?
 

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Look Ma!

Touch0Gray said:
wheel is home, cassette back on, everything adjusted and I gotta say the wheel is DEAD NUTS ON.......The wheel is truer than the tire that's for sure!

Thanks again guys....problem solved!

NOW it can stop raining and clear up...mkay?
I bet you can ride no-handed now :)
 

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Frog Whisperer
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Discussion Starter · #13 ·
maybe.....but not until we are out from underneath the sever thunderstorm warning/tornado watches.....for the next 3 days GRRRRRRRRRRRRRRRRRRRR
 
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