Brocephus

I've searched the web, and done some reading already, but still have a couple questions about dealing with this, so I figured it was time to bring it to The Matrix.
Here's the deal, I recently scored a low-miles urban commuter bike, a 2016 Diamondback Hanjo Metro, on my local craigslist. (I like the concept, the simplicity, etc, and the price was right.)
It's seems to be a smooth, nimble little scooter, but after a few days i noticed the rear wheel lines up noticeably to the left of the seat tube. It seems to line up vertically ok, but just hangs over a good 1/4 inch or so, while the right edge of the tire is almost flush with the right edge of the seat tube (there's a very tiny bit hanging over, depending on how I adjust and tighten the QR).
I've checked the usual things: the axle is firmly in the dropouts and QR is tight. I removed the wheel and reversed it (cassette on opposite side) to make sure the wheel wasn't dished improperly ( nope, it still lines up to the right).
As suggested, i tried riding with no hands, and it does seem a little squirrely, but that seems to be the front end, and after getting out of the driveway and getting a little speed, I was able to ride no-handed fairly well. (I'm normally very comfortable riding no-handed, so I don't know if the front end is a little touchy, as it seems, or if it's related to the rear wheel, but I'm sure it isn't just me.)
The frame is aluminum, so it can't be tweaked like a steel frame can be. Also, as suggested, I measured (more than once) from the front edge of the bottom bracket bolts, to the rear edge of the dropouts, and they both measure exactly the same (17.5").
Being used and from 2016, any warranty claim is likely out of the question. I'm wondering if this is a big deal (other than it just giving me a neurotic twitch ! )
I've read that a shim made from a Coke can may can be used to shift an axle end, and I've also read that some very light filing is possible, to pull the right axle end rearward the tiniest little bit (which will, of course, have a significantly greater effect at the front).
I'm not thinking Dremel tool here, more like a large nail with some emery cloth wrapped around it (done this before on other projects), and lightly buffing the back of the right dropout, pulling that axle back a tiny bit, moving the front edge of the wheel a little right.. I'm thinking about removing just a hair's thickness.
But, the big question here is, is this issue enough to worry about, and could trying to remedy it turn into a train wreck?
I think those are all the facts and details I have. As always, any good info, advice, recommendations,warnings, etc. are much appreciated.

Phil_gretz

It sounds like you have diagnosed the issue, the relative depth of the two rear dropouts. Your remedy is to remove material from the right side. As a test beforehand, why not add a thin shim on the left side to see the outcome? That'll give you an idea on how much material you're to consider removing. That's what I might try before going further. PG

Kapusta

I could not follow everything in your post, but are you sure it is the dropouts that are misaligned and not simply the wheel dish being off?

You can check this by installing the wheel backwards and seeing if it lines up with the frame the same way.

dsbrantjr

I would go further and suggest that after you find the correct shim you just glue it into position. Done.
No need to fix it twice by removing material from the other side, possibly going too far and taking off too much that you will not be able to put back.

Brocephus

Thanks for the replies,guys. And y'all are right, testing with a shim before removing any metal is good advice.

I realize the OP had a fair bit of convoluted info, but I pretty clearly stated that I already tried that.......
"I've checked the usual things: ....... I removed the wheel and reversed it (cassette on opposite side) to make sure the wheel wasn't dished improperly ( nope, it still lines up to the right)."

andrewclaus

The proper tool to use would be Park FFG-2. You could make a gauge something like it with two pieces of all-thread and four nuts and washers.

Brocephus

I believe those are only for use on steel frames, not alu or carbon.

andrewclaus

Yes, but I meant to recommend a home-made substitute just to check alignment.

Brocephus

Well heck, I think the rear wheel is doing that for me already !
But seriously, i did find a video on one of those when I Googled the park FFG-2, but I haven't watched it yet.

Mad Honk 

Brother Bro,
You scored this bike and it won't ride straight???? What am I missing... cause I think the frame was bent at some time. Get a 4 foot 1"X 4" piece of board and set int across the frame triangle and then push it into the rear drop outs. Mark the board where the drop out makes contact and then do the same on the other side. This is the poor mans alignment gauge. I'm betting this frame has been pushed to one side or the other. When you find out which way it was bent use the board in the stay triangle braced against the seat tube to bend it back. If you only want to bend it once and not twice put an axle in the two drop outs and lock it down while bending. And it already is a train wreck sans the audience! Smiles, MH

speedevil 

After you've reversed the wheel in the dropouts, there are two possibilities. One, the wheel is now equally off-center the other way. To me, this would indicate that the wheel dish needs some attention. Two, the wheel is off-center the same way as before. That would indicate that the rear triangle of the bike, the dropouts, have been bent. To confirm this, you can use the string method. it's not perfect but will tell you if your conclusion is correct.

Wrap a string around one of the dropouts, so that it can go forward while lying flat against the outside of the dropout. Go up around the headtube and back to the dropout on the other side, making sure the string comes around the dropout from the outside. The string needs to be clear of any obstructions on both sides. Look at the distance between the string and the seat tube. It should be the same on both sides. If it is noticeably closer on one side, that would indicate that the rear triangle has been bent toward the side with the larger string-to-seat-tube gap.

Depending on what you find, fixing it can either be done by redishing the rear wheel (not overly difficult), or that the frame is bent. If it is a aluminum frame, it may not be fixable. If it is steel, it can usually be bent back into place, carefully. There are YT videos on "cold setting" steel frames, which is usually done to use a longer axle than the frame was originally built to handle.