Mechanics and Fixing Any Questions Answered

Size it big/big plus enough to take up the derailleur as mentioned and you can accidentally go big/big without exploding your drivechain when you forget what gear you're in going up a hill, if there's a bit of slack when you accidentally go small/small you won't break anything.

Another vote for big/big method that snotty mentioned last page, specifically:

The correct way is big/big not through the derailleur plus a pair of links on top of the shortest you could make it, from there you usually add another pair for 1x and another for suspension.

I worked with a very skilled race mechanic who told me this was the standard Shimano method. Also happens to be the Sheldon Brown method IIRC.

Yup Shimano and the right way to do it 99% of the time.
I've found if you're a little slack in small/small and the big/big sizing is ~5mm off letting you take out a link then it's usually fine too.

So it looks like I have an impossible ratio. I've done the big/big/no derailleur and the small chain ring is unusable (i.e. derailleur bends back on itself so the chain touches itself) from about the third largest cog down. I'm now down to adding just one link between the two quicklinks (which I'm not entirely happy with), but big ring big cog pulls the derailleur practically straight. I haven't tried this yet as I still don't know whether that will be any good in the small cog.

Here's how it's looking on the big ring, big cog now...

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And here's what it's like on the small chainring as far as it'll go down the block without the derailleur going back on itself.

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You usually need a long cage derailleur with a triple, and that one looks rather short. If you look hard enough there might be Campag compability chart somewhere that'll tell you what's needed.

Fuck you. Small small and feeeeeel the chain tension. Feeeeeeeeel it.

Yeah that mech has no capacity, just get Shimano innit.

I'll feel you in a minute.

What, just the rear mech. Or are you suggesting I bin the idea of Campagnolo fully and switch everything over to Shimano? (which is ruddy tempting after the palaver I've had trying to source Campagnolo parts).

bin the idea of Campagnolo fully

Obviously this, some people like them for the things they're good at, or because they look nice I guess, but if you're after a wide range of gears and or adaptability then apart from that pricey ekar shit just get Shimano.

If you can do that and have perfect chain length, I'll be ready and waiting

Everything I own is the perfect length.

1/2".

i'm about to build a new gravel/bikepacking frame, which i'd still need a crankset for. i've narrowed the shortlist down to middleburn ro2 and white industries a30. not entirely sure if the middleburns fit with a 73mm bb, but assuming they do with certain spacers.

i'd like to keep the q factor as narrow as possible and made some highly theoretical calculations on the crank arm clearance using my road bike's current setup as a reference. ta'da:

...
reference road bike with 2010 sram force 110bcd cranks (68mm bb)

q factor: 145.2mm
outer stay width @ 19cm (from middle of axle to the outer edge of crank arm on 170mm cranks): 103mm
gap between crank arm edge and chainstay outer edge: 12mm

...
middleburn ro2 (q factor stated online as 153mm, i've added 2.5mm to compensate for the 73mm bb)

q factor 155.5mm (5.15mm wider per side vs. the reference sram force)
new frame outer stay width @ 19cm: 120mm
gap calculated against the reference: 12mm - 8.5mm + 5.15mm = 8.65mm

...
white industries a30 (stated q factor 163.5mm with a 73mm bb)

q factor 163.5mm (9.15mm wider per side vs. the reference sram force)
new frame outer stay width @ 19cm: 120mm
gap calculated against the reference: 12mm - 8.5mm + 9.15mm = 12.65mm

if the calculation is in any way valid, the conclusion would be both models clear the stays easily while the middleburns give a slightly narrower q factor. i've got a chris king bb, which i'd use either the hollowtech kit (middleburn) or the 30mm axle kit (wi) with. not sure if and how this variable changes the calculation.

perhaps someone more knowledgeable can confirm what did i miss and advise how this kind of situation is best approached :D thanks!

Purchased these used a few years ago, not off of here. MT395 brakes and levers.
Both are missing the black part connecting the hose to the lever - is this a standard part, and what is it called? Will I need new levers?
Thanks all

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Standard part -It’s called a shroud nut I think. M8x1.0

Think I've found out what one of the issues is. The inner chainring is a 28-tooth non-standard one rather than the usual 30-tooth, which explains a fair bit. I think I've got a 30-tooth somewhere, so I'm going to fit that and see how it goes. Couple of extra chainring teeth should give me a bit more leeway at least.

LBS will likely have loads of leftover spares, but if you need hose kits they come with.

I got number blind looking at that, but what gravel frame are you getting with a 73mm shell? Most outboard BBs end up at the same width whatever, with spacers compensating for the lack of width on as 68mm shell for MTBish cranks or just 68mm and no spacers allowed for road/grav cranks. I've not played often or in depth with the cranks you mentioned but a quick Google of the Middleburn suggest road only so no 73mm shell frames.

WI has an M for mountain axle so would work, but pricey.

it’s a gunnar rock tour, kind of between gravel and mtb. the build notes specific room for ”an atb triple”, whatever that means…

the a30, a for adventure, from wi is a combination of the mountain axle (for 73mm) and road arms.

mountain axle (for 73mm)

That'll be your option then, or another crankset compatible with 73mm shells, nowt much designed for road or gravel where Q factor will be more of a consideration.

i've narrowed the shortlist down to middleburn ro2 and white industries a30. not entirely sure if the middleburns fit with a 73mm bb, but assuming they do with certain spacers.

middleburn ro2 (q factor stated online as 153mm, i've added 2.5mm to compensate for the 73mm bb)

Middleburn tout the RO2 as a 'road' crank so not sure why it would be compatible with a 73mm bb* and even if it is, the bb shell width won't change the q factor**.

*Shimano make their HT2 mtb cranks compatible with either 68 or 73mm shells, you add spacers between the bb cups and shell to make up the difference, HT2 road cranks are 68mm only. The spindle is shorter and you fit no spacers between bb cups and shell.

**bb shell width has no bearing on crank position. Imagine square taper bb and cranks, a 68mm bb with 122mm axle puts the cranks at the same position from centreline as would a 73, 85 or even 100mm bb with 122mm axle. The only way you could get a wider q factor with the 'burns would be to fit a longer spindle. They are commonly photogrpahed with the spindle fitted in the nds crank but the picture below from the middleburn site shows they are separable and the following page lists different axles that are available - https://www.mountainbikecomponents.co.uk/product/rs8-x-0003-73-mm-2/. That shows a 138mm axle as being for fitting RS8 Xtype cranks into a 68/73mm shell. I'll leave it to you to research whether the RS8 and RO8 cranks share a spindle interface.