ARE CERAMICS TOO DELICATE?

Dear Lennard,
From you article on ceramic bearings in the VeloNews Buyers Guide, I got the impression that these things were not only smooth but also durable, so I ordered a ceramic SRAM BB with the Red crankset for my new bike. I was surprised, to say the least, when the SRAM maintenance instructions advised disassembling and lubing the bearings after every 100 hours of use and immediately after riding in the rain or wet conditions. This suggests that this ceramic bottom bracket is a lot more delicate than conventional ones, which seem to live happily with lubrication once a year. Did I make the wrong choice in sinking $200 into this bottom bracket? I ride about 6,000 miles per year, which means 60 BB lube sessions if I follow SRAM’s directions.
-Bruce

Dear Bruce,
Those are hybrid ceramic bearings on the RED cranks – ceramic balls running in steel races. Those races can still rust.

Perhaps SRAM suggests such frequent lubrication because the seals are lighter (designed for lower friction rather than highest sealing) and therefore less effective than those in a steel bearing bottom bracket. There is also generally less grease packed into a ceramic bearing, so it will run with less friction. Nevertheless, ceramic bearings are very hard, harder than the grit from the road that might get into the bearings, and they can grind up some of that grit, rather than being damaged by it.
-Lennard


TOO MUCH SPEED?

Dear Lennard,
I have a Surly CrossCheck CX bike (52cm frame size, 72 degree head tube angle) with the original Surly steel fork (44mm rake). I am considering switching to the Ritchey WCS Carbon Cyclocross fork (48mm rake) to lose 1.1 pounds off the front end and soak up vibration. Will this result in steering that is too quick at typical CX race speeds?
-Jeff

Dear Jeff,
That will make the steering quicker, but you still will have 5.9 cm of fork trail (as opposed to 6.3 cm of trail with 44 mm of rake). This is still a good amount of trail and will result in handling that is not overly quick for ‘cross racing, in my opinion.
-Lennard


FORKS FOR BIG GUYS

Dear Lennard,
Wound Up makes a great fork for tall riders. They make a fork with a 450mm steer tube and can make that fork with a 500mm steer tube if needs be.

Their forks combine unmatched lateral stiffness with plush fore and aft compliance.
-Jake

Dear Lennard,
Don't forget that Kestrel still makes aluminum steer tube forks perfect for tall guys. It has a 310mm steerer. BTW, I'm 6'5" 220lbs so I'm with you on the big sizes!
-Steven


FOOT PAIN

Dear Lennard,
I read your recent article on foot pain. Not many people know that the ball of your foot is like and upside-down kneecap, with three bones. They are easy to break and they grow back bumpy sometimes. I broke my right ball doing a 50km ski race without insoles when I was 18. Ever since, I’ve had ball of foot issues.

For all my shoes I use a Dremel with this little mace-like attachment (rough ball) to slightly grind the hard sole down, allowing some space for that foot’s ball. Next I use Birkenstock boot insoles (very hard to find), which are unique in that they go under the ball of the feet but do not go under the toes; this prevents numb toes when you fill up the shoe. Another advantages is that they’re cork, which keeps your feet warm in the cold. They also have that tiny ridge in front of the ball of the foot like normal Birkenstock sandals have to keep your foot back in the heel of the shoe even if you are hammering at high rpms, jamming your foot forward into the shoe. For me this works even with my shoes totally unfastened.

I've had about 30 pairs of custom orthotics, from all the “top” experts in the field - and none have made it past a week. Totally useless. It just amazes me that boot fitters and orthotics makers haven't figured out that you put immense pressure on the ball of your foot in cycling and basically zero pressure on the arch and heel. One day, shoe makers will realize this and embed a softer material into the hard sole.
-Ara

Technical writer Lennard Zinn is a frame builder (zinncycles.com), a former U.S. national team rider and author of numerous books on bikes and bike maintenance including Zinn and the Art of Triathlon Bikes and the pair of successful maintenance guides Zinn and the Art of Mountain Bike Maintenance – now available also on DVD, and Zinn and the Art of Road Bike Maintenance, as well as Zinn's Maintenance Tips and Skill Building for Cyclists.

Zinn's regular column is devoted to addressing readers' technical questions about bikes, their care and feeding and how we as riders can use them as comfortably and efficiently as possible. Readers can send brief technical questions DIRECTLY TO ZINN. Zinn's column appears here each Thursday.