Wonkadonk

Firstly, I’ve read up on Sheldon and have investigated with great effort before posting here. I have a wheel issue I have not come across before.

I acquired this bike and would like to get proper wheels and tires for it (and I know most of you will think it’s not worth it but I have my reasons).

The (original?) rear wheel is Belgium-made and is a 525x559 rim with a 26”x1.75” tire and fits the brake caliper.
The front wheel has been replaced with an Araya 26”x1.5” rim and 26”x1.9” tire and is too large for the brake caliper.

The rear wheel looks smaller in appearance, but both are 559 and sidewall height is not much different on the tire.
What is going on here?

I know there are several different sizes of 26” rims, but I cannot find replacements. And both are apparently 559.

So what’s up? Thanks in advance!

cyccommute 

Chances are that they are both 559mm bead. I wouldn’t be too worried that they are marked differently. If you are worried about the size, just swap the tires from front to back and see if they work. (They probably will.)

Is there any other marking on the tires? Sometimes tires are marked with the metric dimensions as well as the imperial.

Although there may be supply chain issues, 26” tires are still fairly widely available. If you want a knobby tire or a smoother tire, you should be able to find them through your local bike shop. QBP seems to have a number of different ones in stock in both 1.6 to 1.9” size and 2.0 to 2.2 sizes. You may be able to find them on-line as well. I did a quick search and found a fair number of different brands and models.

alcjphil

It looks to me as if your fork is bent forwards which is why the rim does not match up with the brake pads

ThermionicScott 

The rims aren't the problem. The front brake looks like it's poorly designed when it comes to tire clearance, or might not be set up right.

You need new tires anyway. A set of slick 26"x1.75" tires would free up some clearance under those brakes, and ride nicely.

Bill Kapaun

The brake reach is simply incorrect for that wheel size. The pads are at the end of the slot and still don't reach far enough.

Crankycrank

+1. Looks freakishly bent forward. Even if the pads could be moved higher they would have to be at an odd angle to match the rim which also hints at bent fork legs. Just to rule it out measure the diameter of each rim to be sure they're the same.

Trakhak

Yes, fork bent forward. Once, a mom and kid brought a bike in the shop to complain that the bike they'd bought from us had a defective fork that looked like that. I said to the kid, "You can get a lot of air, right?" Kid said proudly, "Yeah! None of my friends do the jumps I do!" Had to explain to mom that MTBs are not BMX bikes and can't be treated that way.

andrewclaus

If there's a bike co-op open near you, they'll have a bucket full of salvaged forks and can help you put a new one on. Choose a nice accent color!

alcjphil

All the other 26" rim sizes are larger in diameter than the ones you have now

Wonkadonk

I took pictures of both tire sizes. The front is 1.9; the rear 1.75. No mixing of imperial and metric. I tried a wheel that was 26”x1.5” and was still far too tall for the front.

Wonkadonk

Thank you. That was the easy answer...to change the fork. It’s an old 1” threaded but I could hunt for one. But then, this problem plagued me because I wanted to understand; both front and rear rims are 26” and 559, but the rear one is actually smaller. And what does 525x559 mean? I have not come across a marking quite like that. 559 yes, but not 525x559!

ThermionicScott 

Getting back to the brakes, are they original? Do you know? The fork itself appears to have lots of tire clearance. If it were my bike, I'd replace the front brake with a long-reach centerpull or something.

ThermionicScott 

Your rear rim is not smaller. Perhaps it looks that way because the brake is mounted higher in the rear, but the rims are the same exact diameter where the tires mount, which is what matters.

Wonkadonk

Yes, the brakes are original. Okay, I think that is a good option. Thank you. I still wonder what wheel size would have been there originally.

TPL

Your forks are very BADLY BENT !

Replace your fork and then your brake pads will be 'square' to the rim

canopus 

559 is the original wheel size. The rims, while maybe not original, are the original size.
The front brake doesn't fit/work because your fork is bent... badly. How do I know, because when my BMX bike was stolen when I was a wee little lad, I had to ride the Raleigh 3spd toruing bike we had ( i miss it now, but youth... oh well). I jumped that bike so much that after a while I had to run it into a building to straigten the forks after every jump. Its a wonder I still have front teeth.

ThermionicScott 

What model of bike is this? I figured the fork was supposed to look like that, nothing on low-end bikes really surprises me.

alcjphil

You are confusing tire width with wheel diameter. Wheels that accept 26 x 1.75, 26 x 1.9 and 26 x 1.5 tires are all the same diameter. They will all exhibit the same problem with respect to your brakes reach. Your current front wheel is the same diameter as the original wheel. It is your bent fork that is the problem

Leisesturm

IKR. Except that I don't think that bike is particularly low end. Just old. Looks clunky to us after four decades of steady innovation in metallurgy and component development. You'd think there would be some damage to the paint where the bending occurred. Maybe there is. That isn't the best picture from which to determine this. <hint> <hint>

ThermionicScott 

Yeah, a bent fork didn't really occur to me since I didn't see any obvious cracks in the paint or metal, and usually they get bent the other way!

If the fork started out with more of a normal curve to it, I'm wondering if this was re-aligned after the incident, or if it still tracked straight by some miracle. So many questions...

Wonkadonk

It’s a Raleigh Summit

Wonkadonk

I will take a better picture tonight. The forks do not look damaged in any way, but it could be that I’m a super-idiot, which is possible.

canopus 

Raleigh's had paint that wasn't to hard so it would not break(i.e crack) with a gentle bend, at least for a while.
You forks are bent in a curve that starts about an inch below the crown and follows the blade down.
Also, notice how the pads below are at a 90 degrees to the brake caliper where your's aren't... That's another good clue along with the pad location on the caliper.

Do another test.... Place it on the ground and tell us whether or not your top tube slopes to the front of the bike instead of being parallel to the ground (on a level surface).

Wonkadonk

Wonkadonk