Forum home› Mountain biking forum› MTB workshop & tech

Rough joint on Mavic rims?

alomacalomac Posts: 189
edited January 2013 in MTB workshop & tech
I just took delivery of some wheels I ordered with Mavic EN521 rims and am surprised by how rough the the welded joint looks. The milling away of the welding flash has actually left a visible depression in the rim walls, which isn't the most confidence-inspiring thing I've seen. I gather that this is fairly normal for welded rims, but these are supposed to use Mavic's 'SUP' technology which, according to Sheldon, means that the rim is made thicker than normal, welded and then machined down uniformly to leave a smooth join. Are these depressions something to be concerned about?

Posts

  • Chunkers1980Chunkers1980 Posts: 8,035
    Pics?
  • carbonkidcarbonkid Posts: 52
    i would be sending them back, sounds like they let the apprentice have a go,i make carbon motorbike wheels for a living so should no what im on about, you would hope.
  • cooldadcooldad Posts: 32,599
    carbonkid wrote:
    i would be sending them back, sounds like they let the apprentice have a go,i make carbon motorbike wheels for a living so should no what im on about, you would hope.
    Do you weld them?
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
  • alomacalomac Posts: 189
    Here are a couple of pics. They're straight out of my phone, so the size might be off, sorry.

    One side:
    IMAG0034_zps838591b2.jpg

    IMAG0040_zps2c620c92.jpg

    The other:
    IMAG0037_zps7e067590.jpg

    Both rims are the same, right down to the asymmetry between sides. The photos, if anything, exaggerate the depth of the gouges. I suspect what I'm looking at is normal, even if it doesn't jibe with Mavic's description of the SUP process, but a second opinion never hurt...
  • supersonicsupersonic Posts: 82,708 Lives Here
    Doesn't look right at all, never seen that before.
    GT ZASKAR CARBON TEAM

    VOODOO CANZO

    Come and see me at https://www.facebook.com/biketyke/
  • majormantramajormantra Posts: 2,094
    Unless the photo is grossly misrepresenting things, that looks awful - I'd definitely complain.
  • cooldadcooldad Posts: 32,599
    Robot went mad.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
  • DanDax1990DanDax1990 Posts: 1,201
    That looks horrible...
    My upgraded Voodoo Bokor

    Ribble Sportive 7005
  • The RookieThe Rookie Posts: 27,802
    'ooky copy?
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • stubsstubs Posts: 5,001
    8304372959_16ba8d772d_c.jpg
    P1020436 by fastmongrel, on Flickr

    This what the joint should look like. This is a 6 year old Mavic rim and you can barely see the welded joint.
    Fig rolls: proof that god loves cyclists and that she wants us to do another lap
  • alomacalomac Posts: 189
    Sigh, there goes my Christmas present to myself, I guess. I had the wheel built by Merlin, so I'm sure these are genuine Mavics, just with a production flaw. I'm disappointed that these rims got past Mavic's QC as well as whoever built the wheel at Merlin.

    I'll send Merlin an email and some photos when they open again. I'm ordering from Australia so it will probably be a while before I can get a resolution. Thanks for helping with this everyone.
  • majormantramajormantra Posts: 2,094
    I find it baffling that somebody could build a wheel and not notice this.
  • Nasty1Nasty1 Posts: 108
    hmm. I though Merlins wheels had a really good reputation and ordered my third set from them earlier this year. I must confess that my first 2 sets were bulletproof reliable but this last set, the rear has gone out of true on its second ride..no rock gardens or anything rough, just plain trail work. Maybe Merlins are loosing there touch??

    Cheers

    Adie
  • carbonkidcarbonkid Posts: 52
    cooldad wrote:
    carbonkid wrote:
    i would be sending them back, sounds like they let the apprentice have a go,i make carbon motorbike wheels for a living so should no what im on about, you would hope.
    Do you weld them?
    the carbon wheels have a magnesium hub glued in which has to be cnc machined or welded if its a custom hub
  • chez_m356chez_m356 Posts: 1,893
    carbonkid wrote:
    cooldad wrote:
    carbonkid wrote:
    i would be sending them back, sounds like they let the apprentice have a go,i make carbon motorbike wheels for a living so should no what im on about, you would hope.
    Do you weld them?
    the carbon wheels have a magnesium hub glued in which has to be cnc machined or welded if its a custom hub
    so do you weld/cnc them, or just glue the hub in ? :)
    Specialized Hardrock Sport Disc 10- CANYON Nerve AM 6 2011
  • alomacalomac Posts: 189
    I emailed Merlin with some photos, and here is their response:

    'I have spoken to our wheel builders and mechanics here and shown them the photos. I can assure you that there is no fault with these rims. We have built hundreds of these rims and they are all the same with this heavy weld area on the rim. I can understand your concern with the look of these rims, but this is the same on every en521 we have built and all the stock on our shelf. With the heavy guage of this rim the weld is very large and leaves an indent in the join. We have shown pictures of this to mavic and they have agreed that this is the finish left by the welding process on this rim.'
  • majormantramajormantra Posts: 2,094
    I'm surprised. Maybe the photos are exaggerating things - how deep does it feel when you run your finger over it? I suppose I'm used to looking at rims with a machined braking surface but even so I'm amazed at how bad that looks.
  • supersonicsupersonic Posts: 82,708 Lives Here
    I'm surprised too, never ever seen that before. Send them back under distance regulation laws.
    GT ZASKAR CARBON TEAM

    VOODOO CANZO

    Come and see me at https://www.facebook.com/biketyke/
  • The Northern MonkeyThe Northern Monkey Posts: 19,174
    Check other photos of this rim though, most appear to have a sticker over the welds?
    Santa Cruz Butcher
  • Dick ScruttockDick Scruttock Posts: 2,533
    Found this image online of the join on the same rim, looks interesting to say the least:
    obrecze_mavic_en521_3346.jpg
  • majormantramajormantra Posts: 2,094
    I guess I stand corrected.
  • The RookieThe Rookie Posts: 27,802
    alomac wrote:
    I emailed Merlin with some photos, and here is their response:

    ' are all the same with this heavy weld area on the rim. '
    It's not a heavy weld area is it, it's like someone has taken an angle grinder to it to clean the excess weld off....

    Tried contacting Mavic direct for an opinion?
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • LagrangeLagrange Posts: 652
    alomac wrote:
    I emailed Merlin with some photos, and here is their response:

    We have shown pictures of this to mavic and they have agreed that this is the finish left by the welding process on this rim.'

    Why did Merlin share the pics with Mavic - because they did not manufacture the rim and because they are as concerned as most people in this forum. I think that the rims are poor that the weld will not compensate for the grinding and that the strength is compromsed

    Send them back and a link to this forum and maybe someone who lives near Merlin can check the stock items and get back to the forum?
  • duskdusk Posts: 583
    Rick Draper wrote:
    Found this image online of the join on the same rim, looks interesting to say the least:
    obrecze_mavic_en521_3346.jpg
    My ex729 looks like this except the groove is slightly narrower
    YT Wicked 160 ltd
    Cotic BFe
    DMR Trailstar
    Canyon Roadlite
  • carbonkidcarbonkid Posts: 52
    chez_m356 wrote:
    carbonkid wrote:
    cooldad wrote:
    carbonkid wrote:
    i would be sending them back, sounds like they let the apprentice have a go,i make carbon motorbike wheels for a living so should no what im on about, you would hope.
    Do you weld them?
    the carbon wheels have a magnesium hub glued in which has to be cnc machined or welded if its a custom hub
    so do you weld/cnc them, or just glue the hub in ? :)
    once the hub has been made and painted it is glued in to the wheel
  • chez_m356chez_m356 Posts: 1,893
    carbonkid wrote:
    chez_m356 wrote:
    carbonkid wrote:
    cooldad wrote:
    carbonkid wrote:
    i would be sending them back, sounds like they let the apprentice have a go,i make carbon motorbike wheels for a living so should no what im on about, you would hope.
    Do you weld them?
    the carbon wheels have a magnesium hub glued in which has to be cnc machined or welded if its a custom hub
    so do you weld/cnc them, or just glue the hub in ? :)
    once the hub has been made and painted it is glued in to the wheel
    5500824041_c6d4938b93_z.jpg :roll:
    Specialized Hardrock Sport Disc 10- CANYON Nerve AM 6 2011
  • alomacalomac Posts: 189
    The Beginner wrote:
    Tried contacting Mavic direct for an opinion?

    I want to, but they don't make it easy, Mavic's site gives no contact info and just fobs you off on to the retailer
    Given that it's a custom-built item, I'm not sure I can return the wheels unless Mavic concedes that there's something wrong with the rim (if there's something wrong...).
  • supersonicsupersonic Posts: 82,708 Lives Here
    You still have your consumer rights, and I am pretty sure the DSR still apply to you if you wanted to return them.
    GT ZASKAR CARBON TEAM

    VOODOO CANZO

    Come and see me at https://www.facebook.com/biketyke/
Sign In or Register to comment.