Mack hub bearing

Posted on
of 2
/ 2
  • After splashing out on some Mack hubs, I was a bit surprised that while fitting the newly assembled wheels the front hub has a noticable amount of play in the bearing/hub. It is noticable when lifting and dropping the front of the bike and when you push the rim side to side. I am assuming it's not normal.

    Does it sound like an integral problem with the hub or is it something that can be fixed?

    Thanks for any suggestions...

  • hmm those macks i thought were bomb proof
    check out the mack hubs thread there might be a bit further info on that thread / users reviews etc seems like there are a few people with them on the forum­=2218537

  • ok cheers, i have seen that thread on macks. I might contact the man himself and see what he suggests. Don't really want to go taking them apart before ive even used them.

  • are they brand new?

  • do bike shop / mechanics ever nick the innards out of hubs / headsets etc ? upgrade their own bikes while selling slightly dodgy less good quality bits

  • yup- brand new. I emailed him and he said there shouldnt be a problem with the bearings as he uses Japanese EZO 61902 RS. Through his slightly hard to understand english he says there should be no movement. It is not a massive amount and only noticable when off the bike and pushing the rim side to side and when lifting the front of the bike and lowering on the ground.

    I guess there is no way to adjust these bearings like with the normal cone-type ones?

    Maybe I should just ignore it and only take action if it gets worse...

  • hmmm, interesting. being new to sealed hub bearings myself, i was under the impression they only wobble when the bearings are worn out. are the locknuts tightened down?

    this might help­php/t-619246.html­intenance_and_Repair/Hubs/Cleaning_and_r­epacking_a_hub

  • Ha ha.

    Do the bolts up at the same time you plonker.

  • you do get dodgy bearings, goldtec had a small batch of hubs a couple years back with a similar thing.

  • Cheers for links. Well, I contacted him and he replied:

    I adjust the loose in the hubs during production through appropriate dimensions of the axle and body of hub.
    I can remove the loose in your hub, but I need the best your hub or at least only the axle.
    Also you can give me the dimensions of your axle (look at photo) with tolerance 0,01mm. I will make for you new axle.
    You can ride without any problem with this loose because it doesn't influence the durability of the hub at all.

    Very helpfull guy, so I think I will remove the axle and send it back to him. Must be a slightly dodgy bearing fitting but as he says you can still ride it fine.

  • I've got mack hubs and I've replaced the bearings on the front one.
    You can fit the bearings yourself easily and they just push into the space in the hub itself.

    Sounds to me like it could be a dodgy axle, even when my bearings were knackered on the front one there was no play, it just didn't spin as smooth as before and made a grindy noise.

    And no there's no way to adjust them.

  • interesting cheers, yes I guess it is the axle then. Spins fine, just a bit of movement. Are they easy to get out? is it hammer-time?

  • Instructions:

    Replacement of bearings in the hub
    Prop the hub against something hard in such a way that it leans against the flange, not a fixing screw. Be careful to use the object with no sharp edges, otherwise the flange may get dented or scratched.
    If the hub is fixed/anchored in the wheel, you may put it on your tights/knees. Then you have to unscrew halfway one of the screws ( the one on the top) that fix the hub in the fork. Then –tap the screw with a hammer until the bearing on the other side begins to come out. From the shell/body the whole axle with the bearing will slip out. You have to unscrew halfway the fixing nut/screw on the side of the bearing. Then grip the axle together with the bearing in a vice (the axle should be loose) and by hammering the nut/screw knock the axle out of the bearing. With a long hard tool knock/tap the other bearing out of the hub body.
    These are a standard size bearings so they should be easily available.
    The operation of inserting the bearings requires much more precision.
    Grease those places of the axle where the bearings are to be inserted. Do the same inside the hub body. Put the axle into the hub body and afterwards place carefully the bearings upon the axle ends. Put the serrated covers on the axle and turn the fixing screws. Between the cover and the screw place a fork spanner or another tool and slowly screw the hub together as if fixing it in the frame. Be careful to keep the bearings straight, preventing them from going askew. If they have been placed perpendicularly on the axle and screwed slowly, there shouldn’t be any problem.
    If you have any doubts, please don’t hesitate to contact me. Best wishes and regards.

    This guy in Portland posted up a picture guide too here (Mack used to be called Gromada):­s-gromada-hubs/

    But the pictures are 404ing now. I think if you follow Mack's instructions carefully though you should be ok.

  • cheers mate ill have a play. May just send him the whole hub if it turns out to be a ball ache.

  • Hi to all.

    Try to dowload this:

    It is an image instruction how to replace bearings in Mack's hubs.


  • I know this thread is very old but just got my Mack super light track hubs built up and there is about 2mm of play in the Front hub. The shop I bought the new hubs from have said email Mack which I have done. However I'm starting to think this will end up just costing me. If a shop sells a faulty hub should they pay for a new wheel build if the hub has to be replaced? As the wheels are fully built
    Hopefully we don't get to that point- any help much appreciated

  • How long ago did you buy it from the shop? It might be worth just returning it to the shop for a refund.

  • I know this thread is very old but just got my Mack super light track hubs built up and there is about 2mm of play in the Front hub.

    Not 2mm but I have the exact same issue.

  • Like a month ago-but if I return do they pay for postage and I end up with an unbuilt wheel? Or should they cover postage and the cost to rebuild it. Either way I'm out of pocket I guess

  • Probably less but it's disappointed considering these are not cheap hubs. Have you emailed Mack?

  • Guessing he is taking a while to reply? Seems like people have waited months for an email reply from him

  • so it's built up, have you been riding the wheel in this month?

  • Nope literally got the wheels back from the builder two days ago (was waiting for spokes) put the wheel in the fork and that's when I noticed the movement this morning

  • It is worth taking a quick look to determine the cause of the movement. If it is the (presumably) cartridge bearing, changing them would be more expedient than rebuilding the wheel.

    What is wierd is that I'd think it is quite hard to build a wheel and not notice the hub bearing is loose. It is going to be as obvious in a trueing stand as when you put it on a bike. So the hub vendor might question their paying for a rebuild on that basis.

  • Post a reply
    • Bold
    • Italics
    • Link
    • Image
    • List
    • Quote
    • code
    • Preview

Mack hub bearing

Posted by Avatar for thiscocks @thiscocks