Mechanics and Fixing Any Questions Answered

Cheers - your wealth of information is always much appreciated!

11s chains are a good upgrade for a 10s bike; before 11s the bushings were just stamped into the inner plates, which left a radius. This would've left insufficient bearing area if they'd kept it up, so 11s chains have proper bushings pressed into the inner plates, with more bearing area than 10s... Not sure about whether it's more than 9s though.

Come to think of it, the separate bushings could be of a more specific alloy and/or heat treatment too, but who knows.

Thats useful to know as kmc x93 ten speed get harder to find. The 11 speed are cheaper as well.

I could do with replacing the headset cartridge bearings on both my road and gravel bike and I just wanted to check if anyone knows of a good quality online source? Where do people buy their bearings from?

Where do people buy their bearings from?

General bearing suppliers via ebay mostly but that's tended to be for hub bearings and while for that style of bearing you could easily be looking at 50-90% savings by avoiding cycle specific suppliers, the same sadly wasn't true for headset bearings last time I needed some and the prices were all about the same.

Ok, good to know. Many thanks

could do with replacing the headset cartridge bearings on both my road and gravel bike and I just wanted to check if anyone knows of a good quality online source?

For integrated headsets, it's usually cheaper to buy a complete headset than two bearings.

If it's a Ritchey @TTM, you might be in luck.

That’s depressing

airevelobearings.com stock pretty much everything you could need and prices were about as good as they get last time I checked.

Yeah, saw that. Unfortunately not though -

The headset on my Storck is labelled Acros AI-24 MY06 and takes 6.5 X 41 36/45 bearings.

The other is for my Kinesis Tripster and it’s their own branded headset and a quick google throws these up - https://trailvision.co.uk/products/kinesis-headset-bearings?srsltid=AfmBOormIFSqW-05Z5HWH9I0u6YWr4d0-4y9WrqFBwurvhQNe-rCkUC1

Hello all, I'm having some challenges with a new GXP BB. I've installed many over the years (threaded and pf), and have never had any problems with them, despite the internet seeming to think they are the worst design ever dreamt up.

I'm now trying to install a threaded GXP BB, but on an Italian BB shell. I've ordered a SRAM ita BB and expected the cups to be a couple of mm narrower to make up for the 70mm shell width. However, when I compare to a bsa BB, the shells are exactly the same width.

I did the comparison, as when I tighten up the crank bolts even lightly, the crank rotation is very stiff. Upon inspection, it appears that the NDS splines perhaps don't stick out enough? I suppose this makes sense if the shells are the same width as bsa, as the axle should perfectly fit without spacers when the shell is 68mm?

Have I been sent a dud BB? The threads were fine, so it can't be a bsa one. Is there such a thing as a MTB-specific ita GXP BB that would reduce the need for spacers? I'm quite confused!

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First measure your actual shell width. Is it 70mm? Under the DS Cup, is that a spacer I see before me?

Under the DS Cup, is that a spacer I see before me?

It’s not a groove as to denote a left hand thread?

Should have remembered we are discussing an Italian bb, no left hand threads around.

First measure your actual shell width. Is it 70mm? Under the DS Cup, is that a spacer I see before me?

Already did this before ordering the BB. It is exactly 70mm. There are no spacers in play at all.

I have double checked the cups and they both say ITA on. I just don't understand why they are the same width as the ones used on a 68mm shell that doesn't need spacers. Clearly going to lose 2mm somewhere on the axle?

Have tried to find standard cup widths, but SRAM appear to want to keep their secrets.

Crazy shit! I'd get in touch with SRAM; seems like you might be right about it being a dud?

Can you check if there's a spacer on the DS spindle? (between the wavy washer and the crank).

The other thing I would do is face the shell, as it look like it got paint on it, it won't make that much of a difference but worth doing anyway.

Your other option is running a Shimano hollowtech bottom bracket with an adapter to convert NDS to 22mm.

face the shell

+1 - always a good idea.

I have just bought a bike with di2 and have no di2 knowledge. Rear mech is 6870. I want to micro adjust the rear mech but when press and hold the function button it cycles all the way through the gears and doesn't go into micro adjust mode. What am I doing wrong?

You're using the button on the junction box, yes, not on the rear mech?

yes. this one

You’re holding it for too long and triggering crash protection recovery mode instead. Hold for a couple of seconds only.

merci beaucoup

Thanks. There are no spacers anywhere - not even a wavy washer at the moment. I'll look into getting the LBS to face it.

Does anybody know if the ITA cups should be narrower than the bsa ones?

Does anybody know if the ITA cups should be narrower than the bsa ones?

The fixed axle length and wider shell sort of dictates that they have to be right?

I wonder if they are specific Italian shell cranks with a longer spindle?