Replacing Wheel Rims . . .

laurentian
laurentian Posts: 2,471
edited September 2014 in Workshop
Almost time to get the winter bike out and my rims are concave.

The bike is a 2nd hand Allez that I bought about 3 years ago - looking at photos on-line, it looks like a 2008ish model.

Although I've never done it before, I fancy (with the help of a bike fiddling friend) replacing the rims as the hubs and spokes seem fine (to my untrained eye).

There appears to be a bit of a dark art to wheel building with all kinds of variables coming into play, hub, spke number, effective rim diameter etc. but the existing wheels have no apparent branding or sizing written on them.

Is there a simple way or any tips from those in the know to find out which rims would be the most suitable given that I'm trying to keep the existing hubs and spokes?

Thanks in advance
Wilier Izoard XP

Comments

  • What wheels are we talking about? It might not be at all possible
    left the forum March 2023
  • keezx
    keezx Posts: 1,322
    laurentian wrote:

    Is there a simple way or any tips from those in the know to find out which rims would be the most suitable given that I'm trying to keep the existing hubs and spokes?

    Thanks in advance

    In order to use the existing spokes you heb to select a rim with exactly the same ERD or use another crossing.
  • laurentian
    laurentian Posts: 2,471
    Keezx wrote:
    laurentian wrote:

    Is there a simple way or any tips from those in the know to find out which rims would be the most suitable given that I'm trying to keep the existing hubs and spokes?

    Thanks in advance

    In order to use the existing spokes you heb to select a rim with exactly the same ERD or use another crossing.

    Thanks - sorry to sound a bit daft but how would I establish ERD? Can it be done with a standard measuring tape or does it require a special caliper type device?
    Wilier Izoard XP
  • hypster
    hypster Posts: 1,229
    If you are at all serious about building your own wheels then I would suggest the best investment you can make is to pay for and download Roger Musson's excellent book. All the information you could ever need is contained therein.

    http://www.wheelpro.co.uk/wheelbuilding/book.php

    Failing that could I suggest asking your "bike fiddling friend"?
  • laurentian wrote:
    Keezx wrote:
    laurentian wrote:

    Is there a simple way or any tips from those in the know to find out which rims would be the most suitable given that I'm trying to keep the existing hubs and spokes?

    Thanks in advance

    In order to use the existing spokes you heb to select a rim with exactly the same ERD or use another crossing.

    Thanks - sorry to sound a bit daft but how would I establish ERD? Can it be done with a standard measuring tape or does it require a special caliper type device?

    What wheels?
    left the forum March 2023
  • laurentian
    laurentian Posts: 2,471
    hypster wrote:
    If you are at all serious about building your own wheels then I would suggest the best investment you can make is to pay for and download Roger Musson's excellent book. All the information you could ever need is contained therein.

    http://www.wheelpro.co.uk/wheelbuilding/book.php

    Failing that could I suggest asking your "bike fiddling friend"?

    I don't particularly want to build my own wheels but if I did, I imagine replacing a set of rims would be a good "early exercise" in learning a small part of the art.

    I want to replace some worn out rims to:

    a) save some money as the spokes and hubs seem fine
    and
    b) to have a go at something I haven't done before

    My mate has dismantled and put reassembled a few wheels previously but neither of us have been down the route of replacing old with new. If and when I can get the correct rims, I think we can have a crack at it.

    The immediate and, for the moment, only problem is ascertaining the rims that I need if that is possible given the information that I have or can get. If not, I guess I'll be buying some new wheels.

    Although for £9, that looks a good buy. Thanks.
    Wilier Izoard XP
  • slowbike
    slowbike Posts: 8,498
    laurentian wrote:
    Keezx wrote:
    laurentian wrote:

    Is there a simple way or any tips from those in the know to find out which rims would be the most suitable given that I'm trying to keep the existing hubs and spokes?

    Thanks in advance

    In order to use the existing spokes you heb to select a rim with exactly the same ERD or use another crossing.

    Thanks - sorry to sound a bit daft but how would I establish ERD? Can it be done with a standard measuring tape or does it require a special caliper type device?

    What wheels?
    laurentian wrote:
    but the existing wheels have no apparent branding or sizing written on them.

    Unbranded generic wheels perchance?

    OP - I've done it the other way around, reasonable rim but knackered hub - just bought a Shimano hub with the same number of spoke holes and rebuilt. But having not dished it correctly I only use it for the turbo.

    TBH, stock wheels sold with most bikes are pretty low quality, so I'd suggest buying a cheap pair of wheels (say ~£100) for general use and then play about with rebuilding your existing wheels.

    Sheldon Brown site has this: http://sheldonbrown.com/gloss_e-f.html

    But your easiest way may be to post a picture of your wheels here and someone may recognise them.
  • laurentian
    laurentian Posts: 2,471
    laurentian wrote:
    Keezx wrote:
    laurentian wrote:

    Is there a simple way or any tips from those in the know to find out which rims would be the most suitable given that I'm trying to keep the existing hubs and spokes?

    Thanks in advance

    In order to use the existing spokes you heb to select a rim with exactly the same ERD or use another crossing.

    Thanks - sorry to sound a bit daft but how would I establish ERD? Can it be done with a standard measuring tape or does it require a special caliper type device?

    What wheels?

    This is what I know about the wheels:

    They are on a 2008/9 Specialized Allez (Alloy with FACT forks if that helps)
    They are 700C
    23mm Tyres fit them
    They are probably about 5- 6 years old
    They are not carbon

    I can get spoke count and any other easily measurable dimension if I know what to look for and where to look. I realise that's probably not much info to go on but posted in the hope I might get some pointers . . . if there is simply no way of knowing or finding out these things in order to establish the appropriate rims, I guess I'll be buying some new complete wheels

    Oh, they're black.
    Wilier Izoard XP
  • If they are unbranded generics you are wasting your time... the hubs and spokes are likely to be of such a low quality that the skip is probably the poshest place they should end up. If you fancy a go at building your own wheels, start from scratch... 105 hubs, Sapim or ACI spokes and a pair of decent rims... don't bother practising on tired parts, the result can only be disappointing and put you off building altogether. You also need to invest on tools and if the result is a crap set of wheels, it's just not worth to bother
    left the forum March 2023
  • laurentian
    laurentian Posts: 2,471
    If they are unbranded generics you are wasting your time... the hubs and spokes are likely to be of such a low quality that the skip is probably the poshest place they should end up. If you fancy a go at building your own wheels, start from scratch... 105 hubs, Sapim or ACI spokes and a pair of decent rims... don't bother practising on tired parts, the result can only be disappointing and put you off building altogether. You also need to invest on tools and if the result is a crap set of wheels, it's just not worth to bother

    Cheers - I know you know what you're talking about and so that's probably the answer.

    Frustratingly, they were certainly "branded" at some point as I can see the remains of adhesive around the rims where the stickers have been removed. I'll have one last bash at seeing exactly what information I can get.
    Wilier Izoard XP
  • laurentian wrote:
    Frustratingly, they were certainly "branded" at some point as I can see the remains of adhesive around the rims where the stickers have been removed. I'll have one last bash at seeing exactly what information I can get.
    That's not the problem.. ERD can be guesstimated + or - 1 mm without removing the rim, just by measuring the rim profile... your problem is that the rest of the wheel is probably crap
    left the forum March 2023
  • laurentian
    laurentian Posts: 2,471
    laurentian wrote:
    Frustratingly, they were certainly "branded" at some point as I can see the remains of adhesive around the rims where the stickers have been removed. I'll have one last bash at seeing exactly what information I can get.
    That's not the problem.. ERD can be guesstimated + or - 1 mm without removing the rim, just by measuring the rim profile... your problem is that the rest of the wheel is probably crap

    Understood!
    Wilier Izoard XP
  • Photos would certainly help to identify what rims and hubs you have. Complete guesswork at this point with the OP's generic description.
  • slowbike
    slowbike Posts: 8,498
    don't bother practising on tired parts, the result can only be disappointing and put you off building altogether. You also need to invest on tools and if the result is a crap set of wheels, it's just not worth to bother

    Although if you've got a scrap wheel and an afternoon spare it can be quite nice to rebuild that wheel to see how it goes. As I said earlier - this is basically what I did, with the full expectation of making a cockup and learning from it - safe in the knowledge that I'm not risking much. Result is a wheel I can use for turbo, or rebuild or use for spares... and a better understanding of how to do it better next time!
  • keezx
    keezx Posts: 1,322
    IF it's an ordinary standard wheel with normal spokes/ spoke count (32) I would measure the ERD and search for a suitable rim.
    Just for fun or learning purposes....might give you a cheap spare set.
  • Slowbike wrote:
    don't bother practising on tired parts, the result can only be disappointing and put you off building altogether. You also need to invest on tools and if the result is a crap set of wheels, it's just not worth to bother

    Although if you've got a scrap wheel and an afternoon spare it can be quite nice to rebuild that wheel to see how it goes. As I said earlier - this is basically what I did, with the full expectation of making a cockup and learning from it - safe in the knowledge that I'm not risking much. Result is a wheel I can use for turbo, or rebuild or use for spares... and a better understanding of how to do it better next time!
    This is what I did before building with new components even though the Wheel Pro book suggests not to. At least I wasn't expecting to get it perfect, but used it as practice.

    Totally surprised that the worn out OEM wheel ended up more true than it started. First proper wheel being built now :)
  • redvee
    redvee Posts: 11,922
    If the wheels are those with straight pull spokes like I had on my Allez, ditch them and buy something decent. In the time I had my Allez I broke 4 spokes and each time it cost me £11 to get sorted, £3 for the spoke from CRC and £8 for the LBS to extend the thread 2mm and install.
    I've added a signature to prove it is still possible.