The wheel goes rusty.

May 16, 2009 5:42 PM

Do I need new bike wheels?

Since it's warm out and its perfect weather to start riding bikes again, I figured I'd go tune up my bike ... only to find out that the rims of my wheels are a little bit rusty. Is there anything I can do to fix them, or is it time to get some new wheels?

posted by thecaddy to travel & transportation (12 comments total)

BicycleTutor.com rust removal
posted by Sonic_Molson at 5:54 PM on May 16

Depending on how far and how fast you plan to ride, you might want to replace the wheels with new ones whose rims are aluminum alloy. They'll be substantially lighter and have lower rotational inertia, helping you with acceleration and going up hills. Otherwise you can follow the instructions in the link that Sonic_Molson posted.
posted by brianogilvie at 6:02 PM on May 16

If there's rust on your rims that means they're almost certainly steel, which means that new wheels would almost certainly be an improvement. Need is probably too strong a word, though.
posted by box at 6:03 PM on May 16

Aluminum rims not only spin up faster, but they also stop much faster - lower weight mean they are easier to stop, and brakes grab them better, especially when wet. Better wheels are the best bang-for-your-buck improvement you can make to a bike. The general idea is a lighter bike is easier and more enjoyable to ride, and the parts that move the most make the biggest difference (think of how far a given part of your rim moves for a given amount of forward movement).

All that being said, you can remove the rust and they should be fine, but replace them if they are significantly pitted with rust (ie. not just a plaque of rust, but cavities in the rim). For obvious reasons, you really don't want to have a wheel fall apart while you are riding, particularly the front one.
posted by idiopath at 10:11 PM on May 16

Slight derail, but I feel some of the advice here warrants it. In a steel-to-aluminum rim shift, how much improvement are we talking? Cyclists spend a lot of keyboard strokes talking about how much better X is than Y, but I don't think I have ever seen anything other than anecdotes, and I feel like a lot of what is said is either purely anecdotal or heavily weighted to racing (i.e. extreme end of ability distribution) standards, which are irrelevant to many cyclists. Sure, steel is about three times denser than aluminum... but what does that actually mean in terms of performance? C'mon, people - this is Metafilter. We believe in science here.
posted by McBearclaw at 1:11 AM on May 17

How much of an improvement? Anybody should be able to notice the difference in how aluminum rims ride. It is as straightforward as the difference between combat boots and running shoes. The simplistic version is heavier = more wasted energy. The more miles you put in the happier you will be you upgraded. And if you upgrade, you will find yourself putting in more miles, because cycling will be more enjoyable.
posted by idiopath at 2:51 AM on May 17

Part of the reason that aluminum wheels make such a big difference:

Lastly, low weight in rotating components is even more important. To accelerate a wheel or pedal and shoe system, kinetic energy of rotation must be supplied, in addition to the kinetic energy of linear motion. For example, with a wheel, if the weight is mostly concentrated in the rim and tire it would take nearly double the energy needed to accelerate it than an equal nonrotating weight. In other words, one pound added to a wheel or shoe/pedal system is equivalent to nearly two pounds on the bicycle frame.

Another reason is that new wheels have fresh new bearings and grease in the hubs. As a person who bought a crumby 70's road frame and then upgraded components as I could afford to, I can say that new wheels made the biggest difference in improving my bicycling experience.

Don't feel compelled to buy new wheels, but know that you will enjoy the hell out of them if you do.
posted by clockwork at 3:08 AM on May 17

The energy's not necessarily wasted; heavier wheels take more energy to accelerate, so there's more effort to accelerate and decelerate. If you pootle along at a steady speed, there won't be much in it between the two types of wheels. In any case, the energy lost from aerodynamic drag is an order of magnitude greater, so the OP would probably only notice the mass advantage if they were in full racing crouch.

The one great advantage of alloy rims is the ability to stop in the rain. This is good. Modern rims, because they are so light, are designed to be a consumable - when I was a habitual commuter in (wet, hilly) Glasgow, I'd wear through a set about once a year.
posted by scruss at 4:20 AM on May 17

The question is does this person need new wheels or not? Not whether aluminum is better than steel or the aerodynamic properties of the crouch. How did we get there?

I'd say you should take your bike to a bike shop and have a pro give you an assessment. They know what they're doing, unlike most of us, and have the replacement, if you need one, right at hand. While you're there, see how much a spring tune-up will cost. Always a good investment and usually runs about $35.

For what it's worth, as stated above rusty rims are only a problem if the rust is in the area where the brake pad meets the rim. Sometimes a little emery paper cleans that up. Any hardware store will have black emery paper. You only need one sheet.
posted by birdwatcher at 5:14 AM on May 17 [1 favorite]

Thanks for the advice, everyone. I'll take the bike down to our local public bike workshop next weekend and see if they have any alloy rims available; if they don't, I'll take out the brass wool and light oil and get to work.

The better braking thing alone would make it worthwhile--I don't really ride enough for the weight difference to make a difference, given that I rarely go more than three miles in a go. But not having to bail because my brakes aren't working and my grocery-laden vehicle is about to go into a creek will be pretty fantastic.

Thanks!
posted by thecaddy at 11:08 AM on May 17

Skip the brass wool and buy some barkeeper's friend or something else that contains oxalic acid. Make a paste with it and use a sponge with a scouring pad and the rust will be gone in no time and you'll have shiny rims. If your bike has any other chrome bits, the BKF will make them shine like new too.

I found BKF at a restaurant supply house but I think it's easier to find at everyday stores in the states.
posted by glip at 5:01 AM on May 18

Upshot: I wound up getting a new bike. Rides like a dream.
posted by thecaddy at 9:16 PM on June 3