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The Aerozine Ceramic Two Tone Jockey Wheels are one of those little additions you can make to your bike to give it a bit of individuality and possibly a tiny performance boost. They certainly look bling and in terms of ceramic bearing accesories they are reasonably cheap, but I found them a pig to set up.
Jockey wheels with ceramic bearings can run into hundreds of pounds so it's good to see that Aerozine has managed to keep these two-tone, machined-aluminium alloy offerings under £40. There is also a steel bearing version for £22.99.
Why ceramic bearings? Well, they are claimed to offer less resistance and increased longevity, although that does divide opinion, with some experts we spoke to suggesting that with something so small like these you are unlikely to notice any performance benefits that will matter in the rear world.
Giving the Aerozines a spin between your fingertips prior to fitting, they do revolve with a beautiful lightness, smoother than the Shimano ones they were replacing – but then again they had done a couple of thousand miles.
In the pack you get the two wheels and an assortment of bearing covers for the varying widths of Shimano road (8.1mm), SRAM MTB (8.8mm) and SRAM road (7.9mm) rear mechs. You don't get any mech bolts, so don't lose the ones you've removed.
Once fitted, the gear changes on my road bike were much crisper through my 105 5800 rear mech and shifter, with a much more defined click as the chain snicked up and down the cassette.
Unfortunately, to get to this stage I had to spend ages getting everything set up – and even then things didn't go to plan.
I spent a decade commuting 35 miles a day year round, and I've replaced a lot of jockey wheels thanks to winter grime, salt and sludge destroying them on an annual basis as I wasn't really one for cleaning the drivetrain every week.
Some of them were direct replacements for Shimano or Campagnolo mechs, others were from various other companies, but it was always a matter of dropping the worn ones out and replacing with the new. Job done.
That was what I was hoping for here with the Aerozines, but no.
Straight after fitting them I shifted through the gears and the chain would randomly misalign with the bottom jockey wheel and jam between the wheel and mech cage every few pedal revolutions. It wasn't consistent, so that ruled out a stiff chain link, but I looked at this anyway, and double checked the alignment of the year-old gear hanger: no issues.
After plenty of faffing, I found that toying with how tight the jockey wheel bolts were made a lot of difference, especially the lower one. Undoing it by a quite a few threads made a massive difference, but even with thread lock applied I wasn't a fan of running everything so loose.
I even tried the setup on my other bike, admittedly running an 11-speed 105 groupset too, but the same thing happened.
The first 'spirited' ride was a 50-miler on smooth A-roads and then some laps of the Castle Combe race circuit. Apart from the chain jamming once on a bumpy section of road getting there, no issues.
The next ride, though, I suffered a couple of jams which I corrected by back pedalling, and off I went. Well, until the almighty bang that smashed the rear mech from its cage, and snapped the gear hanger and the outer casing of the cable. Cadence and speed were pretty high but there was very little load passing through, so the damage was quite spectacular.
My thoughts on this are the fact that Shimano's OE equipment jockey wheels come in different forms. The upper, the G-pulley, has a degree of sideways float to allow the pulley to centre on the sprocket after a shift, so the system will tolerate the setup not being quite perfect. It is also 7.6mm from bushing outer to outer, whereas the lower, the T-pulley, is 8.1mm.
Both of the Aerozines are identical, with a width of 8.2mm according to my Vernier caliper, and neither has any float.
This takes away any slack for misalignment whether from the groupset as a whole or even the frame, especially under load. That differing width of 0.6mm at the upper wheel may not sound much, but when you consider how precise the shifting is on current bikes that is quite a tolerance.
Value-wise, well I'm out of pocket, but when they were working smoothly they did offer a distinct advantage over the replaced parts; whether that is a near 30 quid improvement is something only you can decide.
Tacx's T4035 are £49.99 and while they aren't alloy they do have a distinct upper and lower; the Hawk Racings may shun the ceramic bearings, but the alloy wheels are very similar for £2 less; looking at the comments though they can suffer from the same issues.
I could have just been unlucky – maybe they don't work well with a 105 rear mech – but in the specification they should replace any 11-tooth jockey wheel. It's a shame, as the performance benefits are there.
I asked Aerozine and importer NRG for comment on the problems I encountered, but am still waiting for a response.
Crisp shifting and bling looks, but plagued with setup issues
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road.cc test report
Make and model: Aerozine Ceramic Two Tone Jockey Wheels
Size tested: Size 11T
Tell us what the product is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?
Upgrade components for Shimano/SRAM road and off-road rear mechs.
Tell us some more about the technical aspects of the product?
Aerozine lists the following:
Material 7075 Alloy
Bering Ceramic bearing
AFM pack 2 pulley & 12 caps
Finish Twin color - Black / Blue / Red / Gold / Orange / Green
Tell us how the product performed overall when used for its designed purpose
When running right, the shifting feels very crisp plus they do spin very freely.
Tell us what you particularly liked about the product
Tell us what you particularly disliked about the product
Hardly a straightforward swap.
Did you enjoy using the product? No
Would you consider buying the product? No
Would you recommend the product to a friend? No
Use this box to explain your score
When I finally thought I'd got things set up correctly I was very pleased with the performance, but the faff and not knowing whether you're going to suffer from chain jam takes away any benefits.
About the tester
I usually ride: This month's test bike My best bike is: Kinesis Aithein
I've been riding for: 10-20 years I ride: Every day I would class myself as: Expert
I regularly do the following types of riding: time trialling, commuting, club rides, sportives, fixed/singlespeed
With 20 years of road cycling and over 150,000 miles in his legs it's safe to say Stu is happiest when on the bike whatever the weather. Since writing his first review for road.cc back in 2009 he has also had a career in engineering including 3D-CAD design and product development, so has a real passion for all of the latest technology coming through in the industry but is also a sucker for a classic steel frame, skinny tyres, rim brakes and a damn good paintjob.
His fascination with gravel bikes is getting out of control too!