EPOisDope

I have a carbon frame with an Italian threaded bottom bracket which is misaligned. The BB cubs thread into the frame just fine, but when I put the crank in place, it doesn't spin as freely as it should. There is also a bit of wear on the crank spindle where the non-drive side bearings touch it. The crank spindle is all black except where the non-drive side bearings meet it, where the black has mostly worn off and is now silver. There is currently a new Enduro stainless steel BB with angular contact bearings in there with a Rotor Aldhu 30mm crank. I replaced a fairly-worn Rotor BB with that Enduro BB and the crank friction was the same with the Rotor BB (NOT angular contact) in place as well. That Italian Rotor BB doesn't even have seals, so it's not the seals rubbing. I tried putting another Rotor 30mm crank in there (3d+) thinking that maybe the spindle on the Aldhu crank was the problem, but had the same result. I have the preload nut properly tensioned on the Aldhu crank. Loosening the preload adjuster to have a little bit of play does make it run smoother (I don't ride it like that - just testing), but there is STILL more friction than there should be. I also have a GXP BB / crank that I tried which had the same issue in the frame - just didn't spin as freely as it should. If I put the exact same BB / crank (any of the ones I mentioned) in another frame, an old steel frame in this case, it spins freely. Is it possible to reface an italian BB in a carbon frame? I had a steel frame with a BSA BB which had a worse alignment problem than my carbon frame does which I had refaced, and the difference was huge! It spins much better than the carbon frame. I brought the carbon frame to the same local bike shop that refaced my steel BSA frame, but they didn't believe it was possible to reface the carbon frame. Thoughts, other than sending it to Hambini ? The OCD part of me just hates the notion of a misalignment on a crazy-expensive frame causing crank spindle wear / increased crank friction (I wouldn't THINK any more than a 1 or 2 watt penalty) / excessive BB wear. This frame was a warranty replacement because of a stuck seatpost, so while the obvious first step would be to contact the manufacturer, I just can't get myself to do that for moral reasons. My local bike shop already worked to get my original frame warrantied, so I don't want to get them on the black list of the frame manufacturer.


Thanks,
Dave

Branko D

I'd warranty it again. It's just ridiculous that Pinarello doesn't get it right at that price point.

Maelochs

Decent of you to care about the shop, but it is your bike or your shop .... choose one.

If the frame is off, the manufacturer needs to make it right. No question. If they sent you a bad frame to replace a bad frame, they need to send you a good frame. I would contact Pinarello, or have the shop do it after the shop thoroughly examined the issue.

I'd imagine it would be easier to face a CF BB than steel or Al because you could use sandpaper, not a milling machine or whatever .... still have the same issues of securing the frame in precise position and making sure the grinding face is perfectly perpendicular to the plane of rotation ..... but I imagine the actual work wouldn't be much different, maybe just lower grinding-head speed .... I cannot think why It could not be done.

But Pinarello should pay for it. That's not OCD that is merely common sense. If I am paying "crazy" prices for something I expect it to work. Shoot, if I am buying something cheap I expect it to work .... if I am spending a lot I expect it to work Perfectly.

If you are okay with spending tons of money and getting crap, let's do business. I can collect crap all day long--I will even pay shipping. But if you are in any way sensible you will Demand that the factory send you a perfect frame. They screwed up twice .... and your response is to let them rob you?

I don't get it.

Bald Paul

DO NOT try to reface the BB. Any modification you attempt there will most likely void the warranty. And, if it doesn't fix your issue (I don't think it will) you'll have to live with it.

Koyote

If some manufacturer sent me not one, but TWO defective bikes, I'd be pissed. I'd return the second one post haste.

Kimmo 

Every threaded BB in a carbon frame is an aluminium sleeve. Facing it should be no big deal, since every external cup should be threading up to faced metal anyway - if there's paint on the faces, care is required to prevent the paint getting chipped by the cutting teeth of the facer. On a metal frame, I'd take a file and run it over the corner of the BB tube, but on a carbon frame you may not have a corner there, in which case I guess I'd trace a scribe around the cups, cutting a line through the paint, double checking that's enough diameter to clear the cutting teeth.

No biggie for a competent mechanic.

EPOisDope

Well, since my frame is now out-of-warranty, I've searched for someone who can re-face the BB on my frame, but nobody seems willing to try since it is a carbon frame. I'm considering getting a Hambini 24mm BB, which would also mean that I'd have to get a new 24mm Rotor Aldhu crank / spindle since the one I currently have is 30mm. The reason I'm considering the Hambini BB 24mm is two-fold:

1) The bearings in the BB cups for the 30mm spindle are probably smaller and tighter. Case in point is the Rotor steel ITA30 - it doesn't even come with seals, whereas the BSA version does, and I'm assuming that is because they weren't willing to reduce the bearing size to account for the 2mm difference between BSA and ITA. I'm running en Enduro BB right now which DOES have seals, but it is already quite worn after just a few thousand miles, which I'm guessing is because the bearings are simply too small / too tightly packed.

2) With the Hambini BB, theoretically the sleeve between the 2 cups is metal and fits snugly into the 2 cups, which according to his video for another threaded BB style (I want to say T47, but am not sure about that), should help ensure that the crank spindle is aligned with the bearings.

The Hambini BB is very expensive. While someone could argue that it would be cheaper to buy 8 or so Shimano BBs and just change them out every few thousand miles, I'm constantly having to adjust the crank preload right now (using a wavy washer to "auto-correct" preload has at least helped), so I'd like to have a bike that I don't have to noodle with every 3 or 4 rides. Does anyone know of another BB I can try? I love the idea of a BB infinite style press-fit bottom bracket, where both bottom bracket cups are actually threaded together, but the BB design closest to that for italian-threaded frames seems to be the Hambini, which I'm not even sure that I can get in the US.

Maelochs

Wheels mfg has relatively cheap, bullet-proof BBs. https://wheelsmfg.com/bottom-brackets.html

I cannot imagine what is wrong that a BB would need to be adjusted every few rides. I suspect there is more wrong than you know, if you cannot get a BB adjustment to last four rides. BBs are truly "set/forget" components---install and ignore for thousands of miles.

Psimet2001 

Totally lost but that may be just because the OP was a long single paragraph and I just can't with that.

You believe your BB threading isn't aligned because you have mild binding. OK

Here's the secret - that's not a big deal.

Take it to any shop with frame tools and have them chase and face the BB. Yes even on a carbon bike. It's a non-issue. Super common but that's also why we have tools. I clean up every BB on every bike we do. Including pressfit. The tools exist. Knowledgeable people use them.

eduskator

+1000, bring that sh*t back to the store if it's a Pinarello. At this price, they should even pick it up at your house.

Homebrew01

Yup. No big deal with the correct tool.