Ask a Mechanic | BBright, Power Meter, and Bottom Bracket Compatibility, Hub Adjustments, and Road Wheel Recommendations

Welcome to our Ask a Mechanic column where our expert mechanic Daniel Slusser answers your bike maintenance questions. If you have a question for Daniel, please post it on our Facebook Wall or e-mail Daniel directly at

This week we have a big one for you, so settle in and enjoy.



Hi Daniel, I’ve read your excellent blog on compatible BB / Crank systems.

This was really useful in getting my head around what will work with my new Cervelo S5. I’m currently pondering 3 powermeter crankset options:

1)      Rotor 3D Quarq CinQ (using Rotor BBright 24 press fit BB)

2)      Rotor 3D+ SRM (using OE FSA PF30 BB)

3)      Sram Red 2012 GXP Quarq Power meter(using OE PF30BB + Enduro BBright / GXP adapters)

SRAM Red 2012 GXP Quarq Power Meter Crank

You are probably wondering why I have not included the BB30 Sram red option also. The reason is that I have a 2011 Cervolo P4 which I would like to use the power meter on too. You would know the P4 uses a traditional English threaded BB which would not be compatible with the Sram BB 30 option (where as it will work with the Rotor 3D+ using with BSA 30 Rotor cups, or the Rotor 3D using my existing BB)

I’m leaning at the moment to the 3D+ option as it is the lightest / stiffest solution (no need for adapters with either frame I own). Alternatively I’m seriously considering the new 2012 SRAM red Quarq GXP, but I’m a little uneasy about using the enduro BBright GXP adapters in the S5. Would I notice a difference? Is it likely to be as stiff / durable as a system where the spindle interfaces directly with the bearings as the rotor 3d+ does. The Rotor BBright 24 press fit BB also looks good as there is no additional interface between the bearings and the spindle (though this won’t work with GXP).

To throw something else in I’m using Di2 – though I don’t think this will pose an issue with any option. From: Matt


Thanks for your question, Matt. Here is a quick answer: I would go with either of the Rotor options. GXP doesn’t always play well with adaptors, even when everything is done by the book, and with the Rotor cranks that is not an issue. While they won’t shift quite like Dura-Ace, your Di2 system should work more than fine with the Rotor cranks and rings. Between the two Rotor options I suppose it likely comes down to your budget, availability, and power meter preference, but I would go with the 3D+ SRM for the 30mm spindle; but you really can’t go wrong with either option, as Quarq makes a great power meter and is a good company to work with. Congrats on the new S5!



I have a Shimano Deore M525 rear hub that came on my Specialized Stumpjumper FSR that came loose. I have tightened the nuts on the hub with my hands but they keep coming loose and the axle doesn’t spin very smoothly after I adjust it. What am I doing wrong? From: Jeff

Cup and cone hubs are nothing to fear


Many people hate cup and cone style hubs such as your Deore M525 for precisely the problem that you are experiencing. I believe however, that like most hatred; it is born of ignorance.

All Shimano hubs use this system and I can assure you that their engineers are not the type who slept while seated along the back row of their math classes. Cup and cone hubs offer many advantages over their cartridge bearing counterparts. The geometry of the cup and cone function as an “angular contact bearing” that resists side-loading far better than a cartridge bearing.  They are rebuildable down to the individual ball bearings and offer a great deal of setup options as far as grease and adjustment are concerned. Best of all, they can be serviced without any special bearing pullers or dies that are specific to a given size of cartridge bearing (there are often 2 to 3 different sizes of cartridge bearings in any rear hub of this type). Cup and cone hubs just need a little more frequent adjustment than cartridge hubs. This is especially true of the mid-priced and lower end hubs of this type (most OEM hubs on bikes under $1500 use cups and cones).

Now that my defense of cup and cone hubs is done I can answer your question.

To start overhauling your own hubs all you need are a few basic tools. A chainwhip like this one should be in every rider’s toolbox.

Step 1: In order to make the adjustment you first need to remove your cassette. With the wheel off of the bike and the quick release skewer removed place a chainwhip on a cog toward the middle of the cassette. Then place a cassette lockring removal tool into the lockring. Then, using a long handled wrench turn the lockring tool counter-clockwise while holding the cassette with the chainwhip.

Step 2: Before beginning the next portion of the adjustment make sure that you are working over an area that is well lit and is over rags laid out like a rug beneath the wheel. There is a high likelihood that individual ball bearings can fall out of the hub at this point, so be careful. The rags will prevent the balls from bouncing and rolling away. Always keep the wheel standing vertically during the next portion of the instructions to keep the bearings inside the hub where they belong.

Step 3: With the cassette removed you are ready to get to the axle. On the non-drive (disc) side of the hub remove the dust cover with a screwdriver. Then using a 15mm cone wrench hold the cone in place while you use a 17mm standard wrench to remove the axle locknut by rotating it counter-clockwise. Remove the non-drive locknut from the axle. Then back off the cone until it nearly reaches the end of the axle. This will allow you to push the axle through the hub to expose the drive side cone and locknut. With these parts exposed, tighten them against each other using your cone wrench and 17mm wrench. Make sure there is 4mm of axle exposed at the end of the drive-side after you have tightened down on the cone and locknut.

Step 4: Push the axle back into the hub from the drive side. Tighten the cone down until it fully engages the bearings on the non-drive side. Then replace your non-drive locknut and make it finger tight against the non-drive cone. Then use your cone wrench to hold the cone while your tighten the 17mm locknut down with your standard wrench. Don’t worry about which of the two is turning and which is stationary. The vast majority of the time the cone will move and the locknut will be stationary.

Step 5: Check the axle to see if there is play within the hub, or if the axle is binding against the bearings (if it is binding, undo the non-drive side and start with the cone backed off a quarter turn from the last time you adjusted it. Repeat this process until you get it where you want it). Most likely, the axle will be loose once you have tightened down the non-drive side. Then use a 17mm wrench on each locknut and tighten them against each other just 1/8th of a turn. Check the bearing play again and repeat the process until the axle no longer rattles but don’t go so far that the axle does not turn freely.

Now just reinstall the non-drive side dust cover, put your cassette and skewer back on, and you are done. Now that you know how to do this you can rebuild your own hub when the time comes. To rebuild it just replace the damaged parts as needed and you will be back in business.



Hi Daniel.
I recently purchased Team Sky (Arvesen’s) TdeF Dogma 60.1 with Di2 shifting. But, I don’t have wheels for it.  I do not know what parameters I need to know when purchasing wheels and rear cluster. Can you help? From: Mark


I am happy to help, Mark. Any standard road wheelset will work fine. The wheels should be 700c (this is the industry standard diameter for road bikes) and should have 130mm rear hub spacing (again, this is the industry standard at this time). The freehub body for your wheels should conform to the Shimano 10-speed cassette spline standard, which is by far the most common. All you really need to worry about is not buying a rear wheel with a Campagnolo freehub body. There are some very rare SRAM Red only rear wheels that you should also avoid, if you can even find them in the first place. In short, anything on this page will work with your bike so long as Campagnolo is not in the title. The wheels marked as “(SRAM/Shimano)” will all work as well. While pros always race on tubular wheels and tires, I would avoid these for everyday riding because it is difficult to change flat tubular tires without a good deal of prior experience working with them.

The gorgeous Mavic Cosmic Carbone SLR M10

If I might make a recommendation, I would choose the Mavic Cosmic Carbone SLR M10 wheels for their outstanding balance of weight, aerodynamics, ride quality, and uber cool techy carbon fiber finish.  Another lower priced choice that would also be worthy of your ride is the HED Jet 6 FR wheels.

For the rear cluster any Shimano 10-speed unit will work but you will want to get a Dura-Ace 7900 cassette to match the rest of your outstanding race machine. As for cassette size, you might try a 12-27 for its wide range, yet relatively tight spacing that will work well wherever you ride. If you do a lot of climbing however, then I would recommend the 11-28 to get a slightly lower gear for the steep uphills and a slightly higher gear for the steep downhills to follow.

Congratulations on your new ride! I hope to see you out on the road sometime soon.


Follow Up Question

Thank you so much for the clear and easy to read answer. One question: When I look at the wheels on the website I am unsure if they are 23mm. I notice a lot of riders(or at least many of the riders I ride with) are going with a wider wheels/tires than in previous years.  Do you notice the trend? and how do I know if a wheel is a “23”? From: Mark

Rim width is a hot topic these days with everyone moving toward wider rims, and for good reason. The current crop of 23mm rims offer improved aerodynamics, a smoother ride, lower risk of pinch flats, and greater strength. If you can’t tell, I am a fan of them too. Information with respect to rim width can be found on our website under the “Features” tab between the “Product Description” and “Customer Reviews” tabs.

HED Jet 6. Wide wheels like these are the future.

HED pioneered the wide rim movement and all of their offerings are 23mm.  This Powertap wheelset is also 23mm wide if you are interested in a power meter option. Zipp rims are technically 23mm wide but only at the widest point, rather than at the bead where it really matters, at which point it is 21.5mm wide.

Daniel Slusser is a professional bicycle mechanic with over ten years of experience. He holds a bachelor’s degree in business administration from HSU and a master’s degree in history from Cal Poly University. When he is not riding, wrenching, or writing he enjoys spending time with his wife and two children.