[ShortTravelMag]

Just installed a new Next SL crankset, using the RF BB that they make.

Install was the same as any other press fit. But it doesn't spin smoothly at all. Doesn't spin 1mm unless you move the arms yourself. Most BB/cranks don't really spin much, maybe 1/2 to 1 rotation. But I get nothing. Everything is installed right, no extra spacers, the collar is backed off.

Is this normal? Is there really that much of a break-in needed nowadays?

 

[J.B. Weld]

Not normal. I'm not sure what's wrong but I wouldn't ride it like that.

 

[ShortTravelMag]

That figures. I hate pressfit. I guess I can try pulling out the sleeve and try it. That will at least tell me something.

 

[Jayem]

preload?

 

[ShortTravelMag]

Don’t think so. Never spun the collar tight, I’m going to try to remove the spacer in the middle and see what happens. I’d just get a Wheels BB but not sure if they make the slightly odd width I need. 83/107

 

[Gman7]

New bearings are packed tight with grease, they usually don’t spin all that easy. At least not without some resistance. Does the resistance feel uniform or does it vary?

 

[ShortTravelMag]

it's uniform. I'm going to ride it for an hour or so today, check it, and tomorrow I have a Park tool coming that will allow me to pound out one cup without destroying it. Then I'll try pulling the sleeve. Now that I know the BB isn't THAT rare, it's an 83/107 or Downhill standard, I might be able to find a better BB if needed.

 

[J.B. Weld]

New bearings are packed tight with grease, they usually don’t spin all that easy. At least not without some resistance. Does the resistance feel uniform or does it vary?

Op said it wouldn't even spin 1mm, no grease is that thick.

Riding it that way can only cause damage ime.

 

[FJSnoozer]

Sounds like they are misaligned. They will inevitably create a groove in your aluminum RF spindle.

I would reinstall. Was the shell perfectly clean and smooth?


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[MTB Engineer]

Misaligned BB or the frame is not right, though it’s not unusual for PF BBs to take a bit of riding to “break in”. I would ride it for a few hundred km and check again.

 

[dysfunction]

Really? Won't spin a millimeter, and you should ride it?

 

[Jayem]

Sounds like they are misaligned. They will inevitably create a groove in your aluminum RF spindle.

I would reinstall. Was the shell perfectly clean and smooth?


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Seemed more like to me that his BB spacers was off, squeezing the crank against the bearings?

 

[WHALENARD]

I always spin bearings 1 by 1 with my finger before & after install before completing the rest of the process. BB, hubs, pivot, etc. This really helps troubleshoot anything along the way.

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[FJSnoozer]

Seemed more like to me that his BB spacers was off, squeezing the crank against the bearings?

He said the adjustment ring wasn’t in tight, so I am assuming that is not a tension issue due to spacing. Maybe I read incorrectly.

Ive had a BB do this on a bike that was brought to me. It was just not installed true.


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[ShortTravelMag]

Pulled one cup off, and removed the spacer. The spacer wasn't even close to touching either of the cups inside BB. 10-15mm of space on each end. So it's not a matter of rubbing up against the bearings, or anything. It came out easily and shows no sign of rubbing or anything. So I just left it off, it's not doing anything that I can tell.

Each bearing turns the same smoothness just by hand. they just don't feel loose or smooth yet I guess.

I put the cranks back on, used a torque wrench for all fasteners, and made sure the ring wasn't too tight. It was actually slightly looser than it should have been.

I took one hour long road ride yesterday. Not really enough to break in anything i guess.

I made a short video of me spinning them without chain, and with chain. Does that look normal for a brand new BB? Just generally speaking of course.

I used a real Wheels Mfg bearing/cup presser so they seem to have went in straight and correctly.

I just might be over analyzing things. I tend to do that.

 

[frdfandc]

Pulled one cup off, and removed the spacer. The spacer wasn't even close to touching either of the cups inside BB. 10-15mm of space on each end. So it's not a matter of rubbing up against the bearings, or anything. It came out easily and shows no sign of rubbing or anything. So I just left it off, it's not doing anything that I can tell.

Each bearing turns the same smoothness just by hand. they just don't feel loose or smooth yet I guess.

I put the cranks back on, used a torque wrench for all fasteners, and made sure the ring wasn't too tight. It was actually slightly looser than it should have been.

I took one hour long road ride yesterday. Not really enough to break in anything i guess.

I made a short video of me spinning them without chain, and with chain. Does that look normal for a brand new BB? Just generally speaking of course.

I used a real Wheels Mfg bearing/cup presser so they seem to have went in straight and correctly.

I just might be over analyzing things. I tend to do that.

You're over analyzing things. That amount of spin on a new setup is normal. About 1/2 to 1 complete turn with a little bit of effort.

As long as the bearings don't feel like they are binding, which you've already checked, then just go ride your bike.

 

[ShortTravelMag]

It's been a LONG time since I replaced a BB...always have had great luck with any brand on every bike. But this crank change required it, as I had to go from 25mm to 30mm. At least I had the bearing press and tools all ready to go.

Riding is officially commencing.

makes me want a BBinfinite though, I think it was their demonstration video where the cranks spun like 10 revolutions with no chain. LOL.

 

[Jayem]

I have one bike, my chinese fatbike, which has somehow held up amazing over the years, many long races, etc., and the 30mm cranks in the BB spin perfectly, like in a Hambini video. They just go and go and go. None of my other bikes work like that, although my GG is close.

 

[ShortTravelMag]

I didn't really compare the cranks I pulled out, so for all I know, they were the same. Mentally, it's as if your brain says it can feel the drag.

 

[mtnbikerva1]

Pulled one cup off, and removed the spacer. The spacer wasn't even close to touching either of the cups inside BB. 10-15mm of space on each end. So it's not a matter of rubbing up against the bearings, or anything. It came out easily and shows no sign of rubbing or anything. So I just left it off, it's not doing anything that I can tell.

Each bearing turns the same smoothness just by hand. they just don't feel loose or smooth yet I guess.

I put the cranks back on, used a torque wrench for all fasteners, and made sure the ring wasn't too tight. It was actually slightly looser than it should have been.

I took one hour long road ride yesterday. Not really enough to break in anything i guess.

I made a short video of me spinning them without chain, and with chain. Does that look normal for a brand new BB? Just generally speaking of course.

I used a real Wheels Mfg bearing/cup presser so they seem to have went in straight and correctly.

I just might be over analyzing things. I tend to do that.

Seems wrong unless they used THICK grease.