Mavic Ksyrium Elite freehub cracking

sextoke1
sextoke1 Posts: 133
edited September 2017 in Workshop
The wheel is about two years old. Found that the cassette was loose, removed it and noticed a split down the side of the free hub from the threads and running for around 15mm. I also noticed that the hub was rocking alittle bit on the inside. The diameter on the wheel is 25.0mm where the hub mates to. On the hub it is 25.4mm ish. Ordered a new hub so that this would solve both problems. Got it a few days later and when I put it on, I noticed that it has the same rocking on it. Removed it and measured it and it is 25.4mm as well. Put it on anyway and all OK for 150km. Then on a ride it started the rough noice again. Remove it from the bike and the cassette is loose on the hub. Removed the cassette and we have a split on the new hub. I checked again an older Elite wheel I have (2014) and the hub on that one is perfect. The hub is tight on the wheel, the washer is on the inside, all looks good but for the rocking. My ols wheel has the 8mm axel and the newer one has the 9mm system. I am thinking when the chain is in the big sprocket, and if there is heavy load going through it, it puts pressure on the weak threaded area and then it splits. The wheel has done around 10,000km till I had this problem. I would be hard to believe that the the diameter of the surface on the wheel would have worn down to cause this play as the plastic on the hub would wear first. I don't think the axel nuts and the single bearing on the hub supports the whole hub and I stripped down my old wheel to swap over the hubs, thats when I found out the different in the axel sizes ( 8mm and 9mm). With the hub in the old wheel just sitting in the wheel with no axel through it, there was no rocking. ... There is notning wrong with my older wheels and I might put them back on the bike, I am just saving them for some future bike project as they are nicer looking wheels than the newer ones.

Comments

  • Bobbinogs
    Bobbinogs Posts: 4,841
    I am struggling to determine either a point or a question!
  • sextoke1 wrote:
    I would be hard to believe that the the diameter of the surface on the wheel would have worn down to cause this play as the plastic on the hub would wear first.

    It might be hard to believe, but this does happen; the plastic bushing is tough and the hub is aluminium, so both surfaces will wear eventually, especially if it's not well maintained. 10,000 km is a decent amount; have you been regularly servicing the freehub and if so, what lube are you using in it?

    You can buy new plastic bushings that have a slightly narrower internal diameter to accomodate for this wear and eliminate the rocking of the freehub and cassette. If you have a search on eBay for "Mavic Bushing", they're generally referred to as "oversized" and come in a range of sizes +0.0015, +0.003, +0.005 inches etc depending on how badly that part of your hub is worn.
  • sextoke1 wrote:
    I would be hard to believe that the the diameter of the surface on the wheel would have worn down to cause this play as the plastic on the hub would wear first.

    It might be hard to believe, but this does happen; the plastic bushing is tough and the hub is aluminium, so both surfaces will wear eventually, especially if it's not well maintained. 10,000 km is a decent amount; have you been regularly servicing the freehub and if so, what lube are you using in it?

    You can buy new plastic bushings that have a slightly narrower internal diameter to accomodate for this wear and eliminate the rocking of the freehub and cassette. If you have a search on eBay for "Mavic Bushing", they're generally referred to as "oversized" and come in a range of sizes +0.0015, +0.003, +0.005 inches etc depending on how badly that part of your hub is worn.


    The wheel is only just over a year old, there was no servicing of it. What lub would you recommend? I will have a look on ebay for the oversize bushing.