Mechanics and Fixing Any Questions Answered

Beginning to regret buying an Italian bike now; got a Basso Diamante '23 frame, and can I find a fucking manual for anything? Nope. Through a bit of searcing, I finally found out how to adjust the seatpost clamp (Basso don't explain this anywhere), but the saddle clamp is baffling me. No info if it's for carbon or alloy rails, but tightening it up (to apparently 13Nm according to some random internet nerd) still leaves the rails wobbling in the clamp. I guess it's for carbon rails? I'm using alloy. No bother, I'll check online against a picture of the spare clamps you can buy! Oh, mine looks like neither of those. So I can order one and it'll either be the same and still not work, or it will.

Also, cannot get rid of the slight creaking noise when turning the bars. I've used internal routing dampening foam on both brake hoses, and the Di2 wires (because I've already taken the whole fucking bike apart 17 times now trying to stop the noise, so why not) and it's still there. Given up now, I don't even care anymore.

Stupid bikes.

Hi there,

Recently bought a Renthal chainring (apparently exotic 120 BCD) to fit a Raceface Turbine 10s crank..

Trying to mount the chainring I realized need uncommon chain bolt as the chainring is fileted (so only need the “male”)

The needed chain bolt diameter is larger than a standard M8 chain bolt..

Looks like is need 10mm diameter bolt with 0,75 filet..

https://soshanger.com/en/transmission-en/5323-sram-truvativ-chainring-bolt-kit-for-2-speed-xx-116215193060.html

This look like it would fit, by they’re expensive and I’m not sure of the standard

Can anyone help me out with this ? Cheers

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Strange bcd cranks and a strangely threaded chainring, seems like a recipe for trouble.

The female part of the usual chainring bolt setup also locates the chainring by extending through both the crank and the ring. Forgoing the female part in your set up and using the bolts you linked to would leave the ring ‘located’ by the threaded section of a male bolt which sends sub-optimal (cue @gbj_tester to tell us if using a bolt in this manner is fine or likely to end in fiery death?)

I wonder if that chainring is meant to be used with a shoulder bolt though a bit of Googling has failed to bring anything up.

Is this a bad idea:

I have a road bike I'm building up and want to put dia-compe ENE wing shifters to shift a Shimano 11 speed RD on an 11s campagnolo cassette?

I can’t see why it would be a particularly bad idea. One of the benefits of friction shifting is that you are free to mix brands and speeds etc.

There is an argument that for friction shifting, fewer, more spaced out cogs in the cassette gives better results but I’m sure there are plenty people friction shifting 11 and 12 speed set ups. I have an Ene thumby that I’m using with a 10speed mech/cassette and I have been thinking I’d like to try an 8 speed cassette to see if the shifts would feel more ‘positive’ but it does work fine as it sits.

friction shifting 11 and 12 speed

Yep absolutely fine. Few rides to get used to the lever travel per cog, then your good as gold.

When I went back to 9 speed, it felt weird that I needed to move the lever so much.

Only benefit i found was that if your shifter isn't the done up to the right tightness, it can slip a little to the smaller cog.

(cue @gbj_tester to tell us if using a bolt in this manner is fine

It's fine. The chainring isn't pinned to the spider by the bolt shanks, it's clamped to it by the bolt tension and driven by friction. Think of it as a clutch.
I've been using Zipp Vuma Chrono for more than a decade with the chainring held by nine M3 screws threaded directly in the ring. The last Campag Super Record 5-arm chainsets used threaded holes in the inner ring instead of nuts.

it's clamped to it by the bolt tension and driven by friction. Think of it as a clutch.

Interesting!

Was it ‘on here’ that there was discussion of whether cassette/freehub bodies worked similarly, meaning that steel spline protectors on ali freehub bodies were redundant? If not, what’s your opinion of that scenario?

what’s your opinion of that scenario?

I went through that some time ago, and concluded that the clamping force and the smaller clutch plate diameter meant that you couldn't rely on friction to resist every foreseeable torque loading.

Clearly the case, as we've all seen notched splines on freehub rotors 🙂

that scenario

Shimano designs a set of splines clearly meant for steel or at least titanium, and every joker with a CNC mill be like, 'Hey, I can sell you a lighter hub than Shimano, and what's more, it has a super loud freewheel, which is good, for mysterious reasons' and folks thought that was a great deal.

Come 7800, Shimano briefly had a go at abandoning their brilliant freehub design to try everyone else's half-arsed fully floating style with the DS axle bearing close to the centre of the hub, with an aluminium cassette body, they doubled the height of the splines - kind of necessary for using such a soft metal in that spot.

It was a terrible idea, and Shimano realised it. Breaking compatibility like that wasn't necessary, as a few mobs doing ally HG splines with steel strips have shown, and folks who like to have their bearings where they belong were relieved to see the FH-7800 was the lone departure from Shimano's stressed member cassette body design.

If you have any wheels with the chewable splines, you don't need to reach for the chewable antacid - a simple workaround is to use a billet cassette. A somewhat spendy workaround, but you can find Chinese ones relatively cheap.

I have a wheelset with an ally cassette body... I even went and bought a used pair of WH-9000 carbon tubulars just for the 21h hub, which I was going to swap out, until I saw how much worse the flange spacing was (is there a better term when your straight-pull hubs have no flanges?)...

Spoke to the bloke who designed the hubs (they are bloody lovely for cartridge bearing), and he was like, the splines should last better than most ally ones because the cassette body is 3D-forged. So maybe it's possible to make ally almost hard enough for the job... but I wouldn't know, because I threw a billet cassette on there before long.

It's just regular chainring bolts.

Quite a few narrow wide chainrings are threaded too, makes more sense than requiring a female nut.

Cool thank you

makes more sense than requiring a female nut.

Does it though? I can see the functional advantage if the bcd is large enough and tooth count small enough that the chainring nut would be in the way. Otherwise it seems like it takes a thread that’s normally, or at least very often, in steel and replaceable and makes it both non replaceable and from a weaker material.

Otherwise it seems like it takes a thread that’s normally, or at least very often, in steel and replaceable and makes it both non replaceable and from a weaker material.

Manufacturers don't usually specify a high strength steel for chainring nuts, but they make their tarty chainrings from 7075T6. If the steel fasteners aren't at least grade 8.8 (and they probably aren't) then the aluminium is just as strong.

aluminium is just as strong.

Regardless of the grade of ali?

Just that I’ve dealt with several many seized and sheared ali chainring bolts but all that seems to go wrong with steel ones is rounding the allen wrench fitting. And I suppose occasionally they do get a bit rusty.

TLDR: I’ve had more hassle from aluminium than steel in this application so my anecdata says steel is better.