PF30 BB install concerns

Back by popular demand, the general all-things Road forum!

Moderator: robbosmans

User avatar
Drpoomanchu
Posts: 32
Joined: Sun Feb 09, 2014 8:59 am

by Drpoomanchu

I also posted this question in the introduction thread but figured it would get as much traffic as here so I apologize for the double post . This frame is the 2018 Fuji SL. I wanted to pick your brains on something I have not run into. I went to install my Wheels Mfg. PF30 BB tonight and after prepping and inserting the drive side per instructions there was relatively no resistance and the BB bottomed out by hand. It’s almost like the cup is out of tolerance. The cups are carbon. I tried the non-drive side of the bottom bracket in the drive cup with the same results so it shouldn’t be the BB causing the issue. Has anyone had this problem ? Is this acceptable? My last bike I built was a PF and the cups went in tight. I know this bottoms bracket pulls together but this just doesn’t seem right.


Sent from my iPhone using Tapatalk

2old4this
Posts: 366
Joined: Mon Jan 13, 2014 7:26 am

by 2old4this

I have a Cannondale for which the BB fit was extremely tight. Last press fit I installed was bb386evo. Pressing them was the opposite. It wasn't like you pressing by hand but, i could turn the press with a finger... so, I took them out and used blue loctide. I think that was 4-5 months ago. Still no creaking.
The bottom line is; the BBs are inconsistent (there was even a thread here in WW talking about inconsistencies between the BB sizes. You may want search...)
Recently I've installed a t47; didn't I miss the threaded BBs...

by Weenie


Visit starbike.com Online Retailer for HighEnd cycling components
Great Prices ✓    Broad Selection ✓    Worldwide Delivery ✓

www.starbike.com



1415chris
Posts: 1433
Joined: Sat Apr 18, 2009 8:59 am
Location: Surrey UK

by 1415chris

Did you have a chance to check both shell and cups diameters with callipers?

User avatar
Drpoomanchu
Posts: 32
Joined: Sun Feb 09, 2014 8:59 am

by Drpoomanchu

2old4this wrote:I have a Cannondale for which the BB fit was extremely tight. Last press fit I installed was bb386evo. Pressing them was the opposite. It wasn't like you pressing by hand but, i could turn the press with a finger... so, I took them out and used blue loctide. I think that was 4-5 months ago. Still no creaking.
The bottom line is; the BBs are inconsistent (there was even a thread here in WW talking about inconsistencies between the BB sizes. You may want search...)
Recently I've installed a t47; didn't I miss the threaded BBs...
I have searched and found multiple threads concerning PF tolerances and inconsistencies in bottom bracket shell tolerances. There has to be a line drawn where the opening is out of spec and is unacceptable. From what I have read this is not all that uncommon for tolerances to vary but what is unacceptable. Maybe I’m overthinking but it seems abnormal to me. Do people tighten these up and ride.?


Sent from my iPhone using Tapatalk

User avatar
Drpoomanchu
Posts: 32
Joined: Sun Feb 09, 2014 8:59 am

by Drpoomanchu

1415chris wrote:Did you have a chance to check both shell and cups diameters with callipers?
No I have not as I do not have calipers at the moment. That is a good mention, I will see if I can get ahold of some today.


Sent from my iPhone using Tapatalk

User avatar
Drpoomanchu
Posts: 32
Joined: Sun Feb 09, 2014 8:59 am

by Drpoomanchu

I ended up taking the bike to a local bike shop who deals with Fuji frames and they said the openings looked ok and to not worry and to go ahead with install. The BB is fully carbon so I used Teflon as wheels mfg stated torque specs were 35NM to 50nm. I torqued to 25nm first then stepped to 30nm I let the bike sit as I prepped the crank for install I heard a sharp crack noise from the frame. I inspected as much of the inside and outside of the bottom bracket as possible and saw no signs of cracking. I pulled out the bottom bracket and inspected to find nothing. I reinstalled after cleaning and reprepping. I torqued again in the same manner let the bike sit again and about 5 mins later another sharp crack noise.. I inspected again and found nothing. This did not seem normal to me but can this happen and be normal or is there cause for concern. I am on the low side for torque specs.


Sent from my iPhone using Tapatalk

alcatraz
Posts: 4064
Joined: Mon Aug 29, 2016 11:19 am

by alcatraz

Sounds risky to have such a loose cup in the shell. With the shell material being carbon won't it end up deforming and ovalizing the shell?

It's happened before I think with carbon shells. When it happens the solution is to use special oversize cups/bearings.

Check out the video from "hambini" on youtube about bottom bracket tolerances. Some frame manufacturers (Fuji wasn't in the test) have such large tolerances that a bb can't fit all of them. ~200 frames were measured.

/a

User avatar
pdlpsher1
Posts: 4016
Joined: Thu Jul 19, 2012 6:09 pm
Location: CO

by pdlpsher1

For a loose fitting cup I use this product. You can easily find it at an Ace hardware store or an automotive parts store.

Image

jlok
Posts: 2400
Joined: Tue Jun 30, 2015 3:30 am

by jlok

I got the Thread Together BB86 for my TCR ADV SL full carbon BB shell. No problem at all.

Inserted into DS without resistance. Thread in the NDS and tightened it. Used Loctite 660 instead of Teflon grease. No creak no noise. Good luck.

Sent from my SM-G930F using Tapatalk

Rikulau V9 DB Custom < BMC TM02 < Litespeed T1sl Disc < Giant Propel Advanced SL Disc 1 < Propel Adv < TCR Adv SL Disc < KTM Revelator Sky < CAAD 12 Disc < Domane S Disc < Alize < CAAD 10

sharkman
Posts: 1399
Joined: Fri Jun 25, 2004 8:32 pm
Location: the Netherlands

by sharkman

The sl has a carbon bb and 660 will not cure without an enhancer. Giant is quite sloppy on bb tolerances and especially dura ace pressfit should be avoided (especially without the right glue/filler)


Verzonden vanaf mijn iPhone met Tapatalk

User avatar
IrrelevantD
Posts: 857
Joined: Sun Nov 29, 2015 5:47 pm
Location: Near DFW Airport

by IrrelevantD

Drpoomanchu wrote:
Sat Apr 21, 2018 6:33 am
I also posted this question in the introduction thread but figured it would get as much traffic as here so I apologize for the double post . This frame is the 2018 Fuji SL. I wanted to pick your brains on something I have not run into. I went to install my Wheels Mfg. PF30 BB tonight and after prepping and inserting the drive side per instructions there was relatively no resistance and the BB bottomed out by hand. It’s almost like the cup is out of tolerance. The cups are carbon. I tried the non-drive side of the bottom bracket in the drive cup with the same results so it shouldn’t be the BB causing the issue. Has anyone had this problem ? Is this acceptable? My last bike I built was a PF and the cups went in tight. I know this bottoms bracket pulls together but this just doesn’t seem right.
I've installed similar BBs (same design, but 24mm) in three of my bikes. In my Giant Propel, I had to use a press, but it went in with relatively minimal effort. My Specialized Allez Sprint, I was able to push in by hand the same BB that I pulled out of the Propel. When I got my Trek Crockett, I was having trouble getting the SRAM PF30 BB out, so I had the shop install it, and they had to use a press as well, and it looked like it went in really tight.

I honestly wouldn't be too concerned about how easy it went in. What WOULD concern me is the crack you keep hearing a few minutes after installing it. That's where I'd go talk to someone at the shop.
* There is a 70% chance that what you have just read has a peppering of cynicism or sarcasm and generally should not be taken seriously.
I'll leave it up to you to figure out the other 30%. If you are in any way offended, that's on you.

PsyDoc
Posts: 77
Joined: Thu May 06, 2004 4:14 pm
Location: Valdosta, GA

by PsyDoc

Could the popping be due to the BB binding a little during the install and then letting go? Similar to something called "bolt bang" in metal buildings. In my building, when it was new, there would be a loud bang 2-3 times a month for the first 6-8 months that the engineers said was "bolt bang." Basically, during the torquing of bolts, the bolt head wound bind up against the washer and stay that way for quite some time before "unbinding." When it did, it could be as loud as a .22 being fired and scared the bejeezus out of a number of faculty. If the cranks spin smoothly and there's no popping sound when out of the saddle, then you should be fine.

User avatar
Drpoomanchu
Posts: 32
Joined: Sun Feb 09, 2014 8:59 am

by Drpoomanchu

PsyDoc wrote:Could the popping be due to the BB binding a little during the install and then letting go? Similar to something called "bolt bang" in metal buildings. In my building, when it was new, there would be a loud bang 2-3 times a month for the first 6-8 months that the engineers said was "bolt bang." Basically, during the torquing of bolts, the bolt head wound bind up against the washer and stay that way for quite some time before "unbinding." When it did, it could be as loud as a .22 being fired and scared the bejeezus out of a number of faculty. If the cranks spin smoothly and there's no popping sound when out of the saddle, then you should be fine.
I kind of wondered this myself.. if the BB hadn’t actually seated yet and popped into place should be ok. I find it hard to believe that wheels mfg would have you torque a BB to an unsafe range. As I stated, I torqued no more that 35NM for sure and that is the lowest they recommend torquing to. TBH I would rather a inserted aluminum shell for added rigidity as Carbon scares me especially when squeezing on carbon in these super light frames.


Sent from my iPhone using Tapatalk

User avatar
Drpoomanchu
Posts: 32
Joined: Sun Feb 09, 2014 8:59 am

by Drpoomanchu

IrrelevantD wrote:
Drpoomanchu wrote:
Sat Apr 21, 2018 6:33 am
I also posted this question in the introduction thread but figured it would get as much traffic as here so I apologize for the double post . This frame is the 2018 Fuji SL. I wanted to pick your brains on something I have not run into. I went to install my Wheels Mfg. PF30 BB tonight and after prepping and inserting the drive side per instructions there was relatively no resistance and the BB bottomed out by hand. It’s almost like the cup is out of tolerance. The cups are carbon. I tried the non-drive side of the bottom bracket in the drive cup with the same results so it shouldn’t be the BB causing the issue. Has anyone had this problem ? Is this acceptable? My last bike I built was a PF and the cups went in tight. I know this bottoms bracket pulls together but this just doesn’t seem right.
I've installed similar BBs (same design, but 24mm) in three of my bikes. In my Giant Propel, I had to use a press, but it went in with relatively minimal effort. My Specialized Allez Sprint, I was able to push in by hand the same BB that I pulled out of the Propel. When I got my Trek Crockett, I was having trouble getting the SRAM PF30 BB out, so I had the shop install it, and they had to use a press as well, and it looked like it went in really tight.

I honestly wouldn't be too concerned about how easy it went in. What WOULD concern me is the crack you keep hearing a few minutes after installing it. That's where I'd go talk to someone at the shop.
After applying the Teflon to the mating surface it snugged nicely and pushed in rather well. The thing that was unnerving was the pop or crack I heard after the install. I thought to myself, “you have got to be kidding me”. I was dumbfounded and couldn’t believe what I heard. After looking over the bike I found nothing... this is my third complete build and has been nerve racking for the first time. Maybe I’m getting old Image


Sent from my iPhone using Tapatalk

User avatar
Drpoomanchu
Posts: 32
Joined: Sun Feb 09, 2014 8:59 am

by Drpoomanchu

jlok wrote:I got the Thread Together BB86 for my TCR ADV SL full carbon BB shell. No problem at all.

Inserted into DS without resistance. Thread in the NDS and tightened it. Used Loctite 660 instead of Teflon grease. No creak no noise. Good luck.

Sent from my SM-G930F using Tapatalk
Thnx, local shop told me they use 609 and activator to seat theirs. They work allot on Fuji’s. I think they may use delrin cups which I would be ok with. Wheels mfg. says NOT to use any other compounds than grease as the cups thread together and pull tight.


Sent from my iPhone using Tapatalk

by Weenie


Visit starbike.com Online Retailer for HighEnd cycling components
Great Prices ✓    Broad Selection ✓    Worldwide Delivery ✓

www.starbike.com



Post Reply