road fixed wheels question

[bambam]

Looking for opinions and/or facts.

Pictures posted below.

Here is the deal.
I currently have a set of 36 hole low flange hubs laced to some velocity a23s.
These are on a long distance fixie with fenders and conti 25mm tires.

When out of the saddle I will get fender/tire rub occasionally because of flex. Also of note the rear axle is short? The rear nuts have never slipped but extend 1-3 mm beyond the axle.

So, What to do:

1. Skinny tires
2. Higher tension on the spokes
3. New narrower rims
4. New wheelset because of the axle issue
5. If new wheelset, should I go high flange.

What would you do?

If your response is not serious please state so.

Thanks,
BamBam

[PJN]

Guessing there are plenty of engaged threads in the axle/nut interface and that there isn't an axle issue.

[rustychisel]

serious response, the majority of my riding is fixed gear, and I build my own wheels.

I suspect the A23s might not be the stiffest option and that's probably the root cause.

I would, in this order

a) remove or reposition the fender
b) check true and spoke tension
c) consider rebuilding with high flange hub (but that's a small percentage win)
d) maybe a new axle for peace of mind (but if it ain't slipping)

Or get 23c tyres, but understand if this isn't good for you. What is rider weight?

[bambam]

Guessing there are plenty of engaged threads in the axle/nut interface and that there isn't an axle issue.

This is not an issue that I've noticed.

I've never had to retighten my rear wheel.
Front, yes, but I believe it just wasn't tight enough in the first place.

[foon]

I doubt the axle is the real problem, nor is the rim. How much fender clearance do you have now? Depending on what fender you've got, the flex in the fenders may be the real culprit.

I would increase fender clearance first. Do you have pictures of the fenders/wheels?

[oldpotatoe]

Looking for opinions and/or facts.

Here is the deal.
I currently have a set of 36 hole low flange hubs laced to some velocity a23s.
These are on a long distance fixie with fenders and conti 25mm tires.

When out of the saddle I will get fender/tire rub occasionally because of flex. Also of note the rear axle is short? The rear nuts have never slipped but extend 1-3 mm beyond the axle.

So, What to do:

1. Skinny tires
2. Higher tension on the spokes
3. New narrower rims
4. New wheelset because of the axle issue
5. If new wheelset, should I go high flange.

What would you do?

If your response is not serious please state so.

Thanks,
BamBam

I'd first check the tension of the wheel...with a tension meter. A23 are not heavy weights but not light, flexy either.

Axle, not that big of a deal unless you'd like to change it 'just cuz'...

[bambam]

I weigh approx. 170 lbs and on occasion would have 25-35 lbs of extra gear.

I'm not against 23 mm tire but I wasn't sure with an a23 rim if a 23 would be to narrow?

What tension should the wheels be at?

I built these and other wheel so I can adjust them as needed.

They are true and I am using VO fenders. I'll try to post pics later.

Tolerances are tight re dishing is an option as the wheel should be moved 1 mm to the drive side.

[markie]

I guess I would not worry about it. If it only happens occasionally and is limited to the rear wheel I would not let it spoil my ride.

Do you have a rear brake? Are you sure it is not that which is rubbing?

[john903]

I ride a fixed gear and also enjoy long miles out on it. My wheel set is a basic open pro 32 hole to white industries rear and front 32 OP to campy hub, I run from 28c up to 35c tires. I have never had tire rub, but i have had the fender nuts loosen up and the fenders slip enough when riding. Also if you run fenders and a mud flap on your fenders, well it sounds odd, and maybe to simplistic but could the fender flap be hitting the tire as you stand up? I would also suggest as others have to re-tension and true your rear wheel using a tension meter.
Have a great day.

[11.4]

Rub is only between the rear fender and the tire? Two thoughts here. If you aren't rubbing on brakes and aren't rubbing on the frame, your wheel isn't a problem. You may be trying (a) to fit fenders that are too small for the tires or (b) to fit the fenders too close to the tire. Raise the fenders up a quarter inch -- they'll still stop the spray -- and see if it solves your problem. And if not, try going up a size in fenders. Narrow SKS fenders, for example, don't have a lot of clearance with the hardware mounts on the inside, and it isn't hard with the narrow version to get rub on tires. The wheel isn't flexing much or you'd have brake block rub (you're sure that's not what you have?) but fenders can twist around a bit depending on how much the frame itself is flexing.

[Camelstache]

I ride a fixed gear and also enjoy long miles out on it. My wheel set is a basic open pro 32 hole to white industries rear and front 32 OP to campy hub, I run from 28c up to 35c tires. I have never had tire rub, but i have had the fender nuts loosen up and the fenders slip enough when riding. Also if you run fenders and a mud flap on your fenders, well it sounds odd, and maybe to simplistic but could the fender flap be hitting the tire as you stand up? I would also suggest as others have to re-tension and true your rear wheel using a tension meter.
Have a great day.

I have a very similar set up on my fixed gear. I fabricated some DIY fender extenders, and often times...these will rub. I also run 25s. I figure it's a decent trade off for dry feet and dry friends behind me.

[dgaddis1]

How much space do you have between the fender and tire? And not just the fender, but the hardware, where the stays attach to the fender.

What kind of fenders?

I'm using SL23's and 28's, and with plastic fenders and the clearances on my frame, the fenders were too close to the tires. They cleared, but the fenders flex and move some, just enough for the hardware to occassionally rub.

As long as the wheel has decent tension in the spokes I can't see it flexing that much, especially with 36 spokes.

[Ti Designs]

Check everything, lowest force to highest force. In otehr words, first take all of the tension off your chain and then check the wheel bearings. If the chain tension is masking an adjustment problem, just balancing on the bike will cause the rear wheel to move around. Next, put a finger on the fender and push it to the side. If it takes almost no force, fix the fender mount. The last thing to look at is the wheel...

[Coluber42]

I also ride a fixed for long distances, with fenders. I build my own wheels too, also 3x 32h. I have open pro's and the rear is a Phil high flange hub.
Ti Designs is right that you should check that there isn't any play in the hub; it's fairly common for the cones to tighten or loosen when you're taking the wheel off and bolting it back on. Worn hub bearings can also be the culprit, in which case it will gradually get worse until there's no question at all of what the problem is.
But also have a look 'round the edges of the fenders. A certain amount of wheel flex is normal and not a bad thing, and you ideally want enough clearance between wheel and fender that a normal small amount of wheel flex isn't going to rub. Fenders can shift and get out of whack easily, if one stay gets slightly bent when you lean the bike on something, etc. Sometimes they'll be fine all the way 'round except at the bottom edge or in one spot or just where the hardware is in one spot. If it's just that, sometimes you can tug on the stay a bit and straighten it out.
If there's absolutely nowhere the fender comes anywhere close and your hub isn't loose, you might have to tighten the spokes some. A stiffer rim would go a lot further in making your wheel stiffer than a high flange hub would.

If your wheel isn't slipping, I don't see the length of the rear axle being a problem. If your dropouts are thicker than average, that could account for it.

[bambam]

pics posted

Lot of good suggestion to try.
hub play, loose fenders, etc.
I can say that I use to have a leather washer between the braze and the brake bridge, I used an thinner rubber one and it did help a little.

I've never had luck finding spoke tensions dies anybody know what they should be? These are at 890 Newtons but I typically have them around 1150 Newtons on the drive side. They nay have loosened since I built them.

[oldpotatoe]

pics posted

Lot of good suggestion to try.
hub play, loose fenders, etc.
I can say that I use to have a leather washer between the braze and the brake bridge, I used an thinner rubber one and it did help a little.

I've never had luck finding spoke tensions dies anybody know what they should be? These are at 890 Newtons but I typically have them around 1150 Newtons on the drive side. They nay have loosened since I built them.

110 kgf is what you need, DS rear and front. If the wheel is true, then spokes haven't loosened. From the pix, looks like the fender is really close and ofttimes rub here and there is inevitable.

[bironi]

A buddy of mine rides on a23s and claims they turn a 23 tire into a 25. I don't know if that is true, but I have heard the claim from others. I would try some 23s. I bet the problem disappears without much sacrifice in ride feel.

[oldpotatoe]

A buddy of mine rides on a23s and claims they turn a 23 tire into a 25. I don't know if that is true, but I have heard the claim from others. I would try some 23s. I bet the problem disappears without much sacrifice in ride feel.

Only 'issue' with that is some 23mm tires, onto 23mm rims and it can be tough to seat them all the way around..

[bambam]

110 kgf is what you need, DS rear and front. If the wheel is true, then spokes haven't loosened. From the pix, looks like the fender is really close and ofttimes rub here and there is inevitable.

I understand inevitable but I can be on a flat and lean it to make it rub. I'll work the tension/dish out and check fender tightness. I may even put tape on the inside of the rim to pinpoint the rub after I make sure it isn't the brake.

Thanks for the tension force.

Fender is definitely close. In looking at the dish it is skewed toward the non-drive side but if I put the dish guide on the rim and hold it down on one side it is no more than 2 mm away on the other. i.e < 1 mm off.

I thought about trying 23mm tires but was worries about possible leaning it to far and coming off the tread onto the side wall. but then again it is fixed and you typically don't lean them as much.