Ceramic Bearing Idler Pulley

SD2006

One of the little pulley gear wheels (note the expert terminology) on my bike has a ceramic bushing. Is it supposed to be lubricated? I've tried Park Polylube 1000, then 30 wt. oil and both seem to cause a fair amount of viscous drag. Is this an application for dry teflon lube maybe?

Thanks

tafi

ceramic bearings are the latest buzz word in the cycling industry. They are rounder, harder and smoother than steel balls and can therefore provide less rolling friction. They also funcltion quite well with very light lubrication.
They have all sorts of other benefits for high speed which are of no use to cyclists whos bearings have to withstand less than 1000rpm in all cases.
In a low speed aplication a very small amount of light low viscosity (thin) lubricant would be good. The thinner the better. I would be wary of dry lube but there may be someone else who knows better...

Generally these things should be sealed and lubed for life anyway.

SD2006

Thanks for the reply... I did a 20 mile ride yesterday with the 30w in there and found the that it retained a fair amont of viscous drag. I think I'll go with a thinner oil and stay away from wax or teflon.

kdelong

I thought that the ceramic bearings in the jocky pulley didn't need to be lubed. I know that I have never lubed mine, but I haven't owned it long enough for it to fail due to lack of lubrication.

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tafi

Yes I would have thought so too.

artemidorus

I would really be staggered if you could judge the viscosity of your jockey wheel lubricant in a blinded trial. Now that you've lubricated it, I wouldn't touch it for another decade.

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p38lightning

Wait, am I understanding this correctly? You are talking about a ceramic bushing, correct? Is this an older bike? Bushings were used on older bike derailler idlers prior to ball bearings and cartridge ball bearings, be they ceramic or metal. If this is in fact a bushing based idler it should be greased.

pistole

- yes ,

- a Shimano derailleur I had on a bike about 15 years ago , also had ceramic bushing for the jockey wheels.

- its definitely not a new thing.

- don't think that it is supposed to be lubricated.

.

artemidorus

Steel bushings are still used on cheaper jockey wheels. Ultegra jockey wheels are currently ceramic bushings, I believe. I don't think that I've ever seen a Shimano jockey wheel with a ball or cartridge bearing setup.

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SD2006

The only time I notice it is when I spin it by hand, my legs don't know the difference. I figure over the course of 50 or 100 miles it might make a slight difference, but it's not like I'm racing or anything.

JungleBiker

So should Ultegra ceramic bushings be lubricated or not? And if they should, then what lubricant is recommended?

artemidorus

I used light grease. Whether I had to lubricate it, I can't say.

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Peter@vecchios

The pulley the OP is referring to is a bushing, not ball bearings and YES grease them or they will dissolve to dust and kill your pulley.