Corona Rat

[wintermute]

Nothing special, just a simple N+1build (if you can call it that) on a 70's Murray-built Hiawatha I picked up off a fellow forum member to keep me sane during COVID. I removed the chrome fenders, which are in really nice shape, added ape hangers and Thompson grips. It came with that sweet vinyl saddle. I'm thinking about adding a layback seat post, just trying to figure out the geometry. It came with 26x1.75-labelled tires which are actually 1.8" wide. I'd like to get fatter tires on it, but as you can see from one of the photos there's only about 0.3" clearance between the rear tire and the left seatstay. I'd like to try to get something 2.0" wide like WTB Thickslicks or Kinda K-Rads, but I'm concerned that might be pushing it. Thoughts? The other option is to stick with the same width tires and put the nice fenders back on. Any tire recommendations either way would be appreciated.

 

[schwinn boy]

From the last photo your frame looks bent. Try measuring from the dropout to the head tube on one side, then compare that to the same measurement on the other side. if that is the problem once it's corrected you should have a lot more tire clearance.

 

[wintermute]

From the last photo your frame looks bent. Try measuring from the dropout to the head tube on one side, then compare that to the same measurement on the other side. if that is the problem once it's corrected you should have a lot more tire clearance.

Thanks for the help! I've got the same length on both right and left side measured from the dropout to the top tube, resting the tape measure on top of the fork crown. The wheel looks centered between the chain stays, but is shifted between the seat stays, and the wheel is reasonably true, so i guess there has to be a bend somewhere?

 

[Wildcat]

That frame is fairly common and usually takes a 26 x 2.125 tire easily when there aren't any fenders. I've done that a few times. Your bike looks good as is, but a set of wider whitewalls would set it off imo.

With the bike upsidedown, put the wheel in the dropouts with the nuts loose and notice if one dropout seems to be slightly higher or lower. That will shift your wheel towards the left or right seatstay. If the dropouts are level, then the wheel should sit evenly between the seat stays.
If that's the problem, then take a long screwdriver or steel rod and slide through the dropouts where the wheel would go and pull up or down to make small adjustments.

 

[wintermute]

That frame is fairly common and usually takes a 26 x 2.125 tire easily when there aren't any fenders. I've done that a few times. Your bike looks good as is, but a set of wider whitewalls would set it off imo.

With the bike upsidedown, put the wheel in the dropouts with the nuts loose and notice if one dropout seems to be slightly higher or lower. That will shift your wheel towards the left or right seatstay. If the dropouts are level, then the wheel should sit evenly between the seat stays.
If that's the problem, then take a long screwdriver or steel rod and slide through the dropouts where the wheel would go and pull up or down to make small adjustments.

Thanks! Let me see if I understand you - put the wheel in the dropouts with the nuts the little loose, look at which way I'd want to torque the wheel to make it centered, then take the wheel out and torque the stays (at the same time) in that direction? Because I don;t really notice any height difference.

 

[Wildcat]

If the wheel is sitting perfectly straight across the dropouts then something else is wrong. The seat stays still don't line up with the wheel? Post up some pics of the frame. Some folks here have a lot of experience straightening out frames.
From my own experiences, the more a frame is corrected the worse it can get. That's with my basic tools like pipewrenchs and big hammers, bench vise, crowbars and what ever else I can find. I had one Murray frame that had been backed over by a car. When I straightened one part, another part was out of whack. I finally got it fairly straight but it never rode like an untouched frame.