PF30 Bottom Bracket Seal Drag!!??

Discuss light weight issues concerning road bikes & parts.
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by allenpg

I just got a new 2013 Cannondale Evo with their SL crankset. I noticed that the PF30 bottom bracket seems to have a decent amount of seal drag. Is this normal? I've had lots of different BBs over the years, and this is the most that I've experienced. Not too bad. One good spin on the crank arm gets about 2 revolutions. Thanks for the help!

Last edited by allenpg on Mon Dec 17, 2012 5:36 am, edited 1 time in total.

by Weenie

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by tommasini

I can't speak for all the bb3o systems......but when you increase the diameter of the spindle and bearing yoou natually need a larger seal and therefore a larger seal area.......

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by styrrell

I've got a SiSL crank in a pressfit 30 frame. I think the cups bearings are Sram/Truvative. You shouldn't have that much drag. I initially had a problems. One was that the lockring hits the cup. Cannondale has a new lockring that solves that but I just took a belt sander to mine. It helped but still wasn't perfect, so I also sanded down the lip of the crankside cup.

With only one crank arm installed the arm will swing back and forth like pendulum when pushed, std steel bearings.

I'd disassemble the crank and feel the bearings. If they aren't stiff to the touch they shouldn't be stiff when installed unless something is amiss.

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by thisisatest

A number of SRAM's pf30 cups came messed up. apparently some bearings had the wrong number of balls in them.
If yours is the aluminum pf30 cups with FSA bearings, it could be an alignment issue, but first step is to simply remove the crank and feel the bearings. Anything is crunchy, replace it. If both seem smooth, and the crank feels smooth when through one bearing, but then binds as you go through the second bearing, then the bearings are not lined up with each other. Assuming the frame is ok , I haven't seen any EVOs with problems, I would gently remove the cups and reinstall, one cup at a time and test again.
good luck.

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by Boralb

My sisl2 with fsa ceramic bearings also have the same drag you'e mentioned. It max. turns 1.5 rev. without the chain and alloy end-cups on. You can clearly hear and feel the voice of resistance when spinning.
I tried reinstalling the crank but i couldn't remove it. Unfortunately i don't have the kt013 crank removal tool:(

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by Drockspoke

I had a similar problem with a CAADX BB30. I had the bearings replaced by my LBS and they told us it was drag from the chain and freehub. After an arguement and a demonstration they finally realized it was a BB Shell Defect.

Cannondale ended up sending a replacement frame in a different color (Silver frame to match my discontinued red fork...) so our LBS sent the frame out to a machine shop to have the BB Shell aligned.

It still has some drag but it was improved significantly. It's my wifes bike and she loves the color and doesn't race so she's okay with it.

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by allenpg

Thanks for the tips! I'm going to see how it goes after the next 100 miles. I'm used to installing/removing BB30 cranksets all of the time, but have tempted to take this straight to the LBS where I bought it. My wife's Supersix spins perfectly, but it's BB30. I thought PF30 was supposed to have less issues than BB30. Oh, well...

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by Dammit

It's a funny one, I have a SystemSix with BB30, helped a friend change his SuperSix Evo PF30 BB and I was quite uncomfortable with the amount of force needed to unseat the plastic insert to get the bearings out.

Everything seemed quite nicely made/machined/aligned- we replaced the original PF30 insert with the SRM specific alloy cups, which went in perfectly, and the cranks (Hollowgram Si's) span very well afterward.

I couldn't help thinking that it would have been less stressful with my frame- but then it's got an alloy bottom bracket and the SuperSix Evo is pure carbon, so it has to have some form of insert in there.

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by allenpg

I ended up swapping the SRAM PF30 bearing cups. I have some more spin to them with the SISL2 cranks, but not as much as a SRAM crank. Weird. I'm tempted to go with an Exogram for the additional weight savings. My SISL2 are 600g with the FSA rings. A 50/35 Exogram should be about 550g. Thoughts? Thanks!

BTW, the FSA crank on my Slice RS spins nonstop...:)

by Weenie

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by ms6073

I suspect this 'drag' is partly due to the OD of the spindle which typically requires use of a rubber mallet or similar to get the spindle fully seated in the bearings which I think is damaging/deforming the bearings/cages. I use a Hollowgram SRM with Cannondale's SRM specific PF30 bottom bracket that came with the new 109mm spindle, spacers, and ceramic bearings on my cx race bike but after install, despite following Cannondale's instructions and using a headset press with proper bearing shims, I also noticed a significant amount of drag compared to my BB30 cross bike which spins very freely. I should mention that with my BB30 cx bike, I had the ridges machined off to mimic the new 109mm spindle after which, I used a cordless drill and medium and fine grit metal sanding pads to wet 'polish' the spindle's OD slightly such that with a light coat of grease, the spindle is no able to be inserted by hand with only moderate force. After returning from CX Masters Worlds where the freezing conditions, mud, and repeated power washing, ruined the bearings of the 1-week old Cannondale PF30 bottom bracket, so when I replaced the hybrid ceramics with regular bearings, I also opted to perform the same polishing of the 109mm spindle and was happy to find that even with regular bearings, the crank now spins much better.
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