fx3000

I recently had my bike in for some service and it was recommended to me that I replace my front rim. I have a 2004 Trek 1000 and the rim was very worn out on the sides where the brake hits it. That rim that was on it was an Alex AT450, which I think was 622x13mm. The shop only had a rim in stock that was the right size but wider. It's says Alexrims Specialized Globe double wall and is 622x 18mm. The rim on the back is an Alexrims R390 and at 622x13mm and is a more natural width for the bike.

I had questioned the shop about the width of the wider replacement, but I also had mentioned that I was having some problems with spokes popping off on the older and they said the thicker rim would help with this. They said the main difference with the wider rim was that I would have to leave adjust the brake clamp adjuster open futher. It turns out even leaving it wide open I am actually getting a little occassional rubbing. I am also wondering if having a rim in the front that is wider than the back is a bad thing. The occassional rubbing is not good and it might just be in my head but it feels a little out of balance when I ride it.

The shop said it was ok to go with the wider rim in the front but was that a bad recommendation?

dabac

Going from 13 to 18 should indeed be doable by only changing the brake adjustment, and shouldn't lead to a residual brake rub.

And a a more rigid rim can indeed make life easier for the spokes, but usually that means going to a rim with a higher profile rather than going to a rim that's wider. But of course a wider rim can also be radially stiffer. Don't know your rims offhand to be able to tell.
But it's quite rare to have problems with spokes breaking in the front wheel, that's quite rare. Still, if the wheel held together long enough for you to wear out the rim through braking it can't have been too bad.

The "out of balance" thing is most probably mainly in your mind. Most wheels will settle with the valve down, if left to their own devices. There are riders who actually balance their wheels, but I think I've seem some maths somewhere describing the futility of such an action for the rotational speeds reached by bicycle wheels. I place the reflector on the opposite side and call it done.

I can't come up with anything significantly "bad" about having a somewhat wider rim at the front, but then again I don't think it's much of a help either.
The main thing I see is that if you're going to the trouble of having a wheel rebuilt, (with is a fairly labor intensive process), then it really doesn't make sense to use anything but parts that actually match what the customer wants - unless there are some other factors involved, like not having the time to wait for delivery.

Kimmo 

Yeah that's crap IMO... I reckon if they gave a rat's arse, they'd have put the beefier rim on the back for you. Or ordered a more appropriate rim.

It's badly balanced, in terms of putting metal where you need it for strength... a heavier rim is wasted if your old one stayed true. And if your back rim stayed true, putting a heavier rim on is a misdemeanour.

jasonrobo02

I will never visit this LBS and you should look elsewhere. At the least, don't talk to that worker again. If their advice was to leave the adjuster open instead of taking 2 minutes to readjust your cable, then they are total hacks.

HillRider

Absolutely right. It takes nearly no time to reposition the cable and make the brake clearances correct with the qr in it's proper closed position. There is no excuse for that shortcut.

There is no real negative to having mis-matched rim widths but it also implies the LBS sold you what they had instead of what you needed. That would make me leary of ever doing business with them again, UNLESS you HAD to have the wheel back very quickly and were given the choice of using what they had in stock or waiting for the proper rim to be obtained. Was that the case?

fx3000

I was anxious to get back out and use the bike and they would have ordered a more precise rim size for me if I wanted - but the deciding factor for me was when I asked them if it was definitely ok to go with the wider rim as far as safety and performance and the salesperson said I'd be fine and the only difference is I would have to adjust the brake clamp. Also in fairness to them, I only had the tire there, I left the bike at home. In hindsight I wish I didn't do that. Also I think now maybe they were just trying to clear stock that had been sitting on the shelf. I' m thinking about going back and asking for a replacement, but being that I have used it a couple of times I'm not sure what they would do. Well at least I have a little more knowledge about my tires/rims now.

HillRider

Well, that throws an entirely different light on this whole topic.

1. The shop used the rim in stock at your request but offered to get the proper rim if you had been willing to wait.
2. They didn't adjust the brake clearance because they didn't have the bike, just the wheel.

That's not fair. They did offer to obtain the "correct" rim and you chose to buy what they had in stock in the interest of getting the bike back on the road more quickly.

Readjust the brake cable to obtain the proper clearances or ask the shop to do it and use your new wheel with confidence. It will work fine and the shop did no wrong in this case.

desertdork

When I originally read the OP's first post, I thought the shop left the quick release partially open. But, I believe they merely backed off some of the cable tension at the caliper's barrel adjuster and kept the qr in its correct position. I can understand where the latter would be an acceptable means of compensating for a slightly wider rim in many circumstances and shouldn't pose a problem.

However...
...this statement is an issue. I suspect that either the brake pad is still too close to the rim, or the wheel is not true.

EDIT: Hillrider caught the real issue. It would've been best to have just brought your bike, and not just the wheel, to the shop. Get your brake adjusted properly and enjoy your new rim.

fx3000

Thanks for all the replies. You guys are right, I should have brought the bike and not been in such a rush. I'm going to get the brake adjusted and then get back to some good riding.

Kimmo 

I'd suggest attempting this extremely basic operation yourself first. Just make sure to do it up nice and tight when you've got it right.

dabac

Well, unless you have clearance issues(some forks/chain stays can be wickedly tight) a wider rim is perfectly OK in terms of safety. And as long as you stay out of wind tunnels or elite level time trialing it's perfectly OK for performance too.

You wanted a quick fix - they sold you what they had on hand. Maybe not perfect in terms of bicycle aesthetics and cutting edge performance, but the best deal available given the circumstances.

fx3000

You're right - I had a friend show me how to adjust the cable to widen the brake pad clamps and it was very easy. That solved the sporadic rubbing problem.

LarDasse74

As others have said, there is absolutely no reason to avoid a slightly wider rim on the front or rear... as long as the rim is not wider than the tire.

Others have mentioned a performance difference between narrower and wider tires and there is a difference (although a minute one) - if the width of the rim more closely matches the width of the tire, there will be slightly less aerodynamic drag. Very slightly less. This means a wider rim might actually be slightly higher performance than a narrower one. Very slightly higher - you would probably never be able to feel the difference in a million years.

Otherwise any difference you feel is 100% in your mind. Free your mind and your axles follow... I think that is the saying, right?

dobber

So who would pay for having his rear wheel disassembled? Now instead of one wheel being built, we got two. Plus the cost of spokes. Can we for fact state that the 18mm rim would be substantially stronger?

From what I read the biggest problem was the rim was worn out. We don't know what the source of popped spokes was, could very well have been from any number of things.

Grand Bois

I hope you meant to say up.