I have a set of Ksyrium Elites that I train on, I found the front bearings are shot, it feels like the nut was overtightened and now I can feel the bearnings have some drag in them and feel digital, I tried to loosen the nut but the bearings are shot so i am ordering some replacement bearings and have a couple questions.
Are ceramic bearings worth the cost? some people want a fortune for their bearings
I work on aircraft for a living and can get a B767 wheel bearing rated to 155,000 pounds and 300 knots for less money than most people want for a simple bike wheel bearing.
I did some digging around and found some posts about ceramics but most became an argument about cost and who makes the most perfect bearing.
I found a link to Boca bearings and called them, the front wheel can be re-bearing’d for around $42, they tell me that the bearings are ceramic balls and not ceramic coated steel balls as some people here claim.
What am I looking for in a replacement bearing?
has anyone used boca bearing’s?
Is it a good product?
What is the ground speed of a coconut laden swallow?
Joshatzipp who posts here regularly posted some short time back that Zipp high quality and expensive ceramic bearings should be good for 1-2 watts easier effort to go 30 mph.
There are tons of cheaper and lower quality ceramic bearings out there so one should be able to upgrade to ceramic bearings for a lot less expensive. One should also be able to whittle down that 1-2 watt improvement.
Better yet, why not do a search on ceramic bearings on this forum and read up on the subject and make an informed decision of your own?
I used Boca bearings on my RC cars and they were indeed worth a few milliseconds off the lap pace (where laps were around 25-28 seconds, so that’s significant). I will recommend those bearings, though I have never used them on a bike wheel.
That’s classic. Zipp’s gotta be laughing all the way to the bank with that one. It’d probably take me, I dunno, 380 watts on my TT bike to go 30 mph (I’m guessing, but I know it’s a big number). If you’ve ever put out 380 watts for a period of time, you know that the difference between 380 and 378 is unnoticeable. Dollars per gram is out. Dollars per watt is in. Marketing divisions celebrate.
A Cat 4 was getting heckled at the local night crits for pimping his bike with ceramics. It was actually pretty funny. Kinda felt bad for the guy, but he did bring it on himself…
I got the bearings today, they feel sweet but spinning them with my fingers is not doing much, I want to get an extra one and cut it open and look inside, if I do I will post some pictures of what I find.
I got the bearings today, they feel sweet but spinning them with my fingers is not doing much, I want to get an extra one and cut it open and look inside, if I do I will post some pictures of what I find.
Total cost of the front wheel $42 shipped.
I’m not sure about Boca bearings, but most likely you just need to take plastic seals off to see what is inside. I recently replaced bearings on my Reynolds wheels with Enduro ceramic hybrid bearings purchases from http://www.enduroforkseals.com/. Full set (4x6902 for the rear wheel and 2x6901 for the front) costed me $90. I had a good chat with Chris from enduroforkseals.com and decided to replace bearing grease with much lighter bearing oil. I took seals off my new Enduro bearings, cleaned them using auto parts cleaner and lubricated them with Acer Racing bearing oil (http://www.acerracing.com/bearings.html). Please note, I’m using racing wheels only for racing - few hurdred miles a year. If original grease in your ceramic bearings isn’t good and you expect some heavy use, then consider FSA synthetic grease.
The watt savings are for the ones that Zipp uses which are supposedly the best money can buy. Since you have a set, why don’t you weigh them and see what the weight savings would be? That would be the greater advantage of using the cheaper bearings.