Mechanics and Fixing Any Questions Answered

Why wouldn’t you just put the spacers back on the steerer and bolt the cap back on to hold them in place?

In my experience, steel freehubs on ‘nice’ hubs/wheels are much less common than ali and ali freehubs that have bite guards are much less common than those that don’t.

Unless you have a special use case; the wheel will be used for heavily loaded touring, singlespeed, ebike, then I wouldn’t be worrying too much about what your freehub body is made of.

Apologies if this has been covered before. If I ream a headtube for 30.2mm cups, is the headtube reamed slightly undersize for the press fit or are the cups slightly oversize?

Size on size is a press fit no?

Are you reaming with something other than a headtube reamer?

You would think that was the obvious answer, but I once turned up to a start without a front wheel.…

If I ream a headtube for 30.2mm cups, is the headtube reamed slightly undersize for the press fit or are the cups slightly oversize?

The nominal size is 30mm, which is your target for the bore. The cups are 30.2mm to provide the necessary interference. 30.000mm bore will be very tight and might end up shaving material off one or other component depending on the materials and gauges. It will be OK for steel cups in a thin walled steel head tube, but if the cups are at the upper end of their tolerance, expect to see chips of the softer material if you're combining steel and aluminium🙂

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Size on size is a press fit no?

No. If the ring and the plug are truly identical in size, there's no tension in the ring or compression on the plug when they are assembled together.

How much damage is acceptable

If it still works, it's fine, you'll just have a struggle on your hands when you come to changing the cassette.

Uuuugh, the headtube is dead on 30.00 but 0.2mm difference is making me nervous. Where is that list from?

Where is that list from?

I think the origin is Cane Creek.

Knew you’d be the one to ask but didn’t want to @ you at that unsociable an hour.

In my experience, .05-.1mm tolerance for cups is a level of precision that many headset manufacturers fail to hold.

Not sure there's that many hubs where you have an option? Fulcrum, maybe? And the only point of swapping out an ally freehub body which isn't toast yet is to avoid the hassle of getting a cassette of individual cogs off which have bitten in... I guess they can go slightly out of phase as they do so, which might hurt shifting a bit perhaps. Wouldn't bother.

But Red cassette is billet anyway - it has a nice fat splined section on each end, too thick to bite into Shimano splines in ally.

didn’t want to @ you at that unsociable an hour

You can @ me whenever you like, I don't get email notifications for mentions and all my devices are on silent mode overnight anyway🙂

Any reason this 30/46T combo wouldn't work on a 110bcd Quarq DZero Exogram 11R 110BCD GXP Power Meter crankset?

https://www.ebay.co.uk/itm/323752479154

I'm guessing that's a pretty odd combo that no one has actually tried and I'm going to have to just buy one and try it out but I thought I'd ask

I've lost the pedal washers for my Quarq DZero Exogram 11R 110BCD GXP Power Meter cranks. Are they needed (I mean, clearly not) but anyone want to guess at where to find replacements or what spec they are?

https://www.sjscycles.co.uk/pedals-cleats/truvativ-cromo-pedal-washers/

Of all crank manufacturers, Truvatic/SRAM/Quarq have always been the most insistent that washers are necessary.

I don't tighten my pedals like a nutter and haven't had issues yet but if I can get the washers I will use them. Thanks

I think Truvativ's roots in the OEM business makes them wary of the horrible pedals which come with OTP bikes, with wrench flats which extend to the shoulder. All decent pedals have full circle contact at the shoulder and are much less likely to cause any problems when mounted without washers.

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Ah, interesting point. I've not noticed any wear or anything on the metal insert so presume running without is fine but it won't hurt to have them in place. More importantly I found a damaged Di2 batter cable I need to replace - not sure how it happened - it's not like it's getting squished into bottle cage bosses or anything - maybe just an unlikely twist or something?

Is this chain too short? B tension is as far out as it will go.

It shifts and whatnot perfectly OK just want to keep the mech as far off the floor as possible.

114 links. 32t chainring with a 46 largest sprocket. Apparently the mech can handle up to 51 with its long cage.

And yes I will trim and crimp the cable. The chainring bolts are reversed because I've flipped the chainring to try to even out wear.

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Is this chain too short?

If you can engage bottom gear, it's not too short🙂

My neighbour kindly gifted me a bike for family use. It's a Boardman hybrid with an aluminium frame. At some point someone has drilled a hole in the upper (mono) section of the seatstay close to the seat tube to mount a rack using a self-tapping screw. What do we reckon? Safe as houses or amazed that it's lasted this long?

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Alright then let's ball with it!