Time for new rims?

[RichardB]

25-year-old rigid MTB on its original wheels (plain alloy, 26 x 1.75), unknown mileage but obviously getting old and knackered. With new hub bearings, the wheels are running freely and true (to within say 2mm) so they work fine as wheels. However, I am concerned about the braking surfaces of the rims. The surfaces are quite deeply scratched (I assume wear from the brake blocks) and very dull. The brakes work OK, but with a scraping noise, and in wet weather produce a lot of black gunk that gets everywhere. It dries to a grey powder which is very messy. I have tried cleaning and polishing the rims (degreaser, wire wool, autosol, even used a Dremel) but while they look brighter, the problem is the same. As they are quite good wheels apart from this, I am reluctant to junk them. I don't think the wear is significant in terms of the integrity of the rim; it's more cosmetic. My feeling is I have worn through some hardened layer or hard finish and I am now down to plain metal, but I don't know enough about how rims are made. My wife's bike (same model) is much better, but has had a lot less use over the years.

Is there a treatment for me to bring them back to shiny 'n' smooth, or should I call it a day and get a new pair?

If it's new wheels time, any suggestions for where to get them? I can get a pair from Halfords of unknown quality for around £60. The bike isn't good enough to justify spending megabucks, but I want something that will be robust and reliable. Must be plain alloy without logos or advertising, and stainless spokes preferred. Don't mind small or large flange hubs. Any suggestions welcome.

 

[Milkfloat]

Have you considered that it is the brake blocks not the rims?

 

[Dan Morinary]

If there is no sign of the rim wear line I would junk them. Safety is paramount and you can pick up basic wheels fairly cheep.

 

[I like Skol]

Keep using them. Rim wear goes with the territory and you will most likjel fi d the rims let you know when it is time to replace.

 

[RichardB]

Have you considered that it is the brake blocks not the rims?

Fair point. It's had various random brake blocks over the years (bought on price only, not quality, from memory) but even with new blocks the problem is there. A poor quality block would account for the black gunge in the wet, but not the grey powdery stuff that comes off it, which I assume is the alloy of the rim itself.

If there is no sign of the rim wear line I would junk them. Safety is paramount and you can pick up basic wheels fairly cheep.

No wear line visible - I'm not even sure it ever had them. Perhaps it is time for a new wheelset. Thank you - I tend to agree, but I thought I would consult the oracle before binning them.

 

[RichardB]

Keep using them. Rim wear goes with the territory and you will most likjel fi d the rims let you know when it is time to replace.

I guess that is my question - is this what they are telling me?

 

[Dan Morinary]

I would be cautious. 25 years? Can't complain about not having good innings from them!
Would you feel confident giving the brakes some welly bombing down a winding decent? Would not be pretty if rim gives up.
Personally I would play safe.

 

[Ajax Bay]

This is difficult to give useful advice on as only you can see the wheels. If you've just replaced the bearings, it'd be annoying to then have to replace them.
By the way I think

true (to within say 2mm)

isn't 'true'. Get that spoke key out.

 

[RichardB]

I would be cautious. 25 years? Can't complain about not having good innings from them!
Would you feel confident giving the brakes some welly bombing down a winding decent? Would not be pretty if rim gives up.
Personally I would play safe.

There are a lot of fairly steep hills round here and I don't feel too concerned when descending, but that is probably 'ignorance is bliss'. I think I will get the tyres off and have a good look inside and out. Probably safest to replace if there are major signs of wear

This is difficult to give useful advice on as only you can see the wheels. If you've just replaced the bearings, it'd be annoying to then have to replace them. ... Get that spoke key out.

It wasn't the cost of the bearings, so much as the time it took to get them 'right' from 'nearly right'. But yes, annoying.

Fair point about the spoke key. They are 'true enough' rather then 'true. Must try harder!

 

[RichardB]

Right, new rims ordered. I found some basic rims (Tru-build) on the Raleigh website, cheaper than Halfords. As the bike is a Raleigh, I'm hoping they will feel at home. To be delivered to my LBS within the week.

Thanks for all the comments. I just needed persuading

 

[Dan Morinary]

If you don't get a quarter of a century out of them I would kick off!
I'm more cautious now since I bought an old rigid mtb with a wrecked front wheel where the brake block had sheared into the rim. He was selling the bike due to being thrown in front of a bus when it happened. Scary!

 

[ChrisEyles]

Too late now since you've bought the rims (though I agree that after 25 years you've got your money's worth!), but if you have similar reservations on another wheelset you could get hold of some calipers and measure the rim thickness at the most concave point of the wear on the braking surface. That's probably the only way to accurately assess how much life they've got left in them.

 

[yostumpy]

if price is your only consideration, a cheap complete set of wheels might have been cheaper than LBS built ones with cheap rims. Too late now tho. Hope they work out ok, and hope your 25 year old free hub stills runs smooth.

 

[RichardB]

If you don't get a quarter of a century out of them I would kick off!
I'm more cautious now since I bought an old rigid mtb with a wrecked front wheel where the brake block had sheared into the rim. He was selling the bike due to being thrown in front of a bus when it happened. Scary!

Agreed, I have had my money's worth out of them. It was only the fact that they were original to the bike (which is getting a bit retro now) that made me want to keep them. The old rims are in fact a bit worse than I thought (see below).

Too late now since you've bought the rims (though I agree that after 25 years you've got your money's worth!), but if you have similar reservations on another wheelset you could get hold of some calipers and measure the rim thickness at the most concave point of the wear on the braking surface. That's probably the only way to accurately assess how much life they've got left in them.

I've given them some harsh testing in the last couple of days and under hard braking they have an obvious high spot on both front and rear, jerky braking like warped discs on a car. I could get the micrometer on them, but I don't see the point any more. Scabby, scored, dull, and out of shape - it's time for the bin. (Same could be said of me.)

if price is your only consideration, a cheap complete set of wheels might have been cheaper than LBS built ones with cheap rims. Too late now tho. Hope they work out ok, and hope your 25 year old free hub stills runs smooth.

My mistake; I wasn't clear. By 'rims' I meant wheels. Raleigh do the wheels fully built, but they don't post them out, they send them to the LBS for collection later. So I have done what you suggested. At under £50 for the pair, if they last me a couple of seasons I will be happy.

Thanks all.

 

[RichardB]

Just a quick update: the new wheels arrived at my LBS on Thursday, I collected them yesterday and fitted them this morning. They are nothing remarkable, just alloy wheels, but they run true and look clean and tidy. Braking is vastly improved, as they run true and there is no distortion to the rims, so brake clearances can be tight. They even feel a bit easier and faster, although I am sure that is psychological.

One small issue was that the rear wheel comes with a threaded hub, whereas the old one was a cassette on a freehub. So I had to get a new freewheel and sprockets. The only one available locally was a Halfords own-brand 14-28 (the old cluster was Shimano 13-30) so I have lost a bit of gear range. The sprockets and freehub were the next stage in the restoration, so that has just been brought forward a bit, and I rarely used the 30T anyway, so no great loss.

All in all, very pleased. The wheels were £46 the pair (French rims, built in UK) delivered to my LBS and the freewheel was £15, so not too spendy., and if I upgrade them again in the future they don't owe me too much. Thanks for the help guys.