I have a supersix evo hm disc which came with what I think are hollowgram si disc wheels (made in conjunction with stans). The rear wheel bearings seem totally knackered but I can't find any reliable info online to know what they are and how they are replaced. I have no problem asking a local shop to do it but would like to at least know what needs doing before resorting to that.
Has anyone found anything online about these wheels? What are the bearings?
Thanks
Have a go at taking them apart? You might get them going temporarily while you work out that you need.
Or are you still riding it?
Not riding it but I discovered at nearly 9pm on a Sunday evening and now I'm away with work for a couple of days. Will definitely attempt to have a closer look on Wednesday but any info in advance is appreciated.
I seem to remember reading that the Stans connection is just for the rim bed/bead shape. Certainly the higher end SL Disc wheels come with DT Swiss hubs.
Yours seem to have "Hubs: HollowGram custom, 39t/3-pawl freehub for fast engagement, sealed precision bearings". Could be rebranded DT Swiss 350s? Ah no - someone here says they are Formula : https://forums.roadbikereview.com/cannondale/endcaps-hollowgram-disc-hubs-362466.html
Thanks for the info. Almost can't believe they are formula hubs on such a high end bike so I'll keep looking for info. One post and a link to some mavic wheels on amazon is certainly a mysterious trail...
There will be freehub bearing and hub bearings, the knackered ones with be a pair of 6903 inside the hub itself in my experience. I have exactly the same problem with my set. I've changed them twice in 500 miles so presume something inside isn't straight. Unfortunately my bike was ex-dem and no warranty.
They're easy to service. Take off the rotor and cassette, one end cap pulls off to reveal a hole perpendicular through the axle, wedge an allen key in here then stick a 4mm (I think) in the other end of the axle and you'll undo the opposite end cap. There's a circlip holding the freehub on which needs to come out then you can just pull it apart. After this it's a normal hub and hub can just tap out the axle and the bearings and press new ones in. A suitable bearing press can be had off eBay and it's a pretty straightforward job.
I agree, they're terrible hubs and it's a bit of a shame on a rather nice bike. Hope it helps.
Super helpful,thanks.
I thought I should turn this thread into a solution rather than another dead end for some future person who is dealing with the same or similar issues.
My particular issue was that the wheel just didn't spin freely and I felt like it was sticky all the time, both in the freewheel and on the axle. I had the bearings replaced by a bike shop (twice) and that didn't seem to solve the problem so I decided to buy some tools and crack on myself. The main thing you need is a bearing press and I found a decent and low cost option at bearingprotools.com (no affiliation to me).
The wheels - mine are Cannondale branded (as per the topic) but the hubs are made by Formula. It turns out these shitty hubs are used very widely by Cannondale, Boardman, Cube, Giant, Syncros, Scott and possibly others. That was a helpful link to make because searching for spares became much easier.
The freehub is a 3 pawl design and is a total no frills design. The bearings in the freehub are 6802 and they can be pressed in easily from both sides as the freewheel slides off the axle. The freehub itself is labelled FH536 and you can find lots of places to buy a new one for about £30 (which comes with some cheapo bearings already installed).
The axle is a very thin aluminium looking thing and has 6903 bearings. Once I'd taken this apart I realised that the two bearings were not making a tight contact on the inner race and it looks like the axle itself has been worn down. I haven't taken calipers to it but it's obvious by eye. I ordered a new axle only from GiantBikeSpares although the axle is the same in lots of different kits so I just bought the cheapest.
I bought NTN bearings from bearing king as they were the cheapest legit NTN bearings I could find although I have previously bought from AireVelo too. I replaced with full contact NTN bearings and the difference in bearings is immediately noticeable in hand. The NTN ones are so much smoother than the stock ones (comparing new with new).
Overall, they aren't great hubs and shouldn't be on a £4-5k bike but that's the way things have become. You can keep the wheel running smooth/fast by ensuring the freehub, axle, and bearings are newish and well greased but in the long run I think switching to a dt swiss star ratchet design is probably more sensible but YMMV.
Finally, to press in one of the 6903 bearings you need an over axle type press because the axle has to be in place due to the design.
Hope that helps some future person!
Where to buy spares:
Westbrook cycles have lots and lots stuff listed under Syncros Formula hub repair kit. What's a bit odd is that very similar kits are listed under different brand names and for different prices so look carefully before ordering.
Cannondalespares.com has a bunch of stuff
Giantbikespares.com also has loads (and actually has slightly different stuff to cannondalespares even though it's clearly the same product - worth checking both)
Bearing King for NTN bearings (or AireVelo - but they are generally more expensive)