Riding on an "untrue" rim



Motobecane

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Nov 5, 2010
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So i wanted experiment with wheelbuilding after having a couple of more spokes break on an old used wheel I bought. The rim was not in very good shape and probably shouldn't have been reused, but I figured "what the hecks, spokes aren't super expensive" I got both hubs serviced and in good working order and built the wheels up. I think I did a decent job getting them together considering they were pretty beat up rims but it got me wondering, just what happens when you ride on a rim that isn't true? What does more damage or is more dangerous, riding a rim that is out of true laterally (warped) or one that is out radially (has a hop in it)?

I think I learned enough building these wheels to successfully lace up and build my 2 new deep v's but I'm wondering about the durability and usefulness of these two that I rebuilt. I'm a clyde so obviously I will be seriously stressing them but I see sub 150lbs mexican delivery guys riding bikes with rims in all sorts of disrepair, seemingly without issue. Should I just throw these on my commuter for a bit and see how it goes? I know braking is compromised with a severly warped rim, but I feel like i got them true enough that it wont affect braking all tha tmuch
 
Riding a rim with a hop in it can be very much a non-issue, as most of the time you'll be riding on a surface whose undulations will be greater than the hop in the rim. And riding an untrue rim slowly usually isn't much of an issue either.
But eventually you'll come to a break point between speed and degree of lateral transition where the result is a nasty shimmy when you ride. Insisting to ride a bike with such a noticeable shimmy will eventually result in a rather strange wear pattern of the tire.

Durability (of the wheel) is mostly down to what's going on with the spoke tension. Untrue, but decently tensioned wheels can live for a long time.
 
Originally Posted by Motobecane .

So i wanted experiment with wheelbuilding after having a couple of more spokes break on an old used wheel I bought. The rim was not in very good shape and probably shouldn't have been reused, but I figured "what the hecks, spokes aren't super expensive" I got both hubs serviced and in good working order and built the wheels up. I think I did a decent job getting them together considering they were pretty beat up rims but it got me wondering, just what happens when you ride on a rim that isn't true? What does more damage or is more dangerous, riding a rim that is out of true laterally (warped) or one that is out radially (has a hop in it)?

I think I learned enough building these wheels to successfully lace up and build my 2 new deep v's but I'm wondering about the durability and usefulness of these two that I rebuilt. I'm a clyde so obviously I will be seriously stressing them but I see sub 150lbs mexican delivery guys riding bikes with rims in all sorts of disrepair, seemingly without issue. Should I just throw these on my commuter for a bit and see how it goes? I know braking is compromised with a severly warped rim, but I feel like i got them true enough that it wont affect braking all tha tmuch

Both lateral and radial deviations from the true can bring their own hazards but if you can get it true enough to where it doesn't affect braking then it'll be true enough to ride safely. I'd start of your first ride real slow and apply the brakes gently and take it from there.

I'd say you'd be better off, if you wanted to experiment with wheelbuilding, spending a nominal fee for a new rim - doesn't have to be anything fancy but something that's round and not warped from the get go. It's tricky enough as it is and it's not just the rim being out of whack that's the only gotcha. If you're reusing an old rim, make sure than the inside of the eyelets are clean to stop the nipple heads from galling or being difficult to turn due to corrosion. A q-tip with a light covering of gear lube to apply a very thin smear of lube on the inside of the eyelet prior to building will help.

Jobst Brandt's "The Bicycle Wheel" is one of the best books on the subject. There's plenty of info on the net from Jobst on the subject - do a google search for "archives Jobst Brandt". If you see a results pointing to yarchive.net that'll be one of the places to go.

Jobst isn't shy about calling out people who are obviously wrong - his posts are as entertaining as they are informative.
 
i left in the garage for years a Campagnolo hub with a - severely - untrue rim, the result was that it damaged the flange of the hub and i had to throw it to the trash can... wise me :(
as a secondary effect you might say that it looks bad to ride with an untrue wheel all the time, giving the impression that you don't care and will prompt other riders to avoid riding with you for example.
 
yeah, i actually bought an ebook on wheelbuilding from a british guy, it is excellent. I'm planning to build with a couple of brandnew deep v's next week and i wanted to test a wheel build on something else. if i use these beat up rims, i'll be using them on a commuter bike that will only be going a couple miles at a time at relatively low speed, or i may look to sell them but i'd advertise them for a food delivery guy in the city, someone who doesn't weigh a lot and only going to be goina couple blocks at a time with them.

as for ruingin the hubs, these aren't very nice hubs so not really worried about that.

Originally Posted by swampy1970 .




Both lateral and radial deviations from the true can bring their own hazards but if you can get it true enough to where it doesn't affect braking then it'll be true enough to ride safely. I'd start of your first ride real slow and apply the brakes gently and take it from there.

I'd say you'd be better off, if you wanted to experiment with wheelbuilding, spending a nominal fee for a new rim - doesn't have to be anything fancy but something that's round and not warped from the get go. It's tricky enough as it is and it's not just the rim being out of whack that's the only gotcha. If you're reusing an old rim, make sure than the inside of the eyelets are clean to stop the nipple heads from galling or being difficult to turn due to corrosion. A q-tip with a light covering of gear lube to apply a very thin smear of lube on the inside of the eyelet prior to building will help.

Jobst Brandt's "The Bicycle Wheel" is one of the best books on the subject. There's plenty of info on the net from Jobst on the subject - do a google search for "archives Jobst Brandt". If you see a results pointing to yarchive.net that'll be one of the places to go.

Jobst isn't shy about calling out people who are obviously wrong - his posts are as entertaining as they are informative.
 
Originally Posted by vspa .

as a secondary effect you might say that it looks bad to ride with an untrue wheel all the time, giving the impression that you don't care and will prompt other riders to avoid riding with you for example.
This is exactlly what I think when I see a guy riding an un-true wheel day after day. Is it really that hard to fix the [SIZE= 36px]FREAKIN [/SIZE]thing man!!!!!
 
Originally Posted by ambal .




This is exactlly what I think when I see a guy riding an un-true wheel day after day. Is it really that hard to fix the [SIZE= 36px]FREAKIN [/SIZE]thing man!!!!!

in this case, yes. no amount of "truing" will render these wheels straight. the rims themselves are out of wack. But they served the purpose to let me figure out how to properly lace and build a new wheel and i did enough tnkering in an attempt to get them true that I think I learned how to properly build up a decent rim.

As for the spoke tension, they are tensioned pretty high but again, because the rims themselves are so damaged, there are some spokes with less tension than others which I know can lead to problems. ultimately, I'm gonna put some rubber on these wheels tomorrow and give them a little test run around the block and see how they do.
 

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