Hi all,
Im looking to change a few bolts on my bike to anodised versions….
Does anyone know what the sizing is on the f/mech bolt,brake caliper bolts,avid elixir lever mount bolts??
Help is much appreciated!

take the existing bolt out and measure it 1) across the thread and round up, then 2) the length of the shaft up to the bottom of the head. then you have Mx X y.
ie an M5 bolt will measure just under this ( about 4.8mm from memory ) across the thread diameter, and a typical length might be 10mm. the bolt is therefore described as M5x10.

Anodised are alloy – dont stick alloy bolts in high stress area – brake caliper bolt a big no no !

Forgot about that!! Ill leave the calipers then.

Cheers Del, i thought that was how to measure them!

Rotor bolts should be fine tho?

Slight spanner in the works is that countersunk ones are measured to include the head, not just the threaded bit.

rotor bolts …. and how are they differently loaded to your caliper bolts ? wouldnt do rotor bolts , caliper bolts , bar clamps , chainring bolts

would do – brake and shifter clamp bolts , stem bolts , headset top cap bolt , seat clamp , pinch bolts , bottle cage bolts , front mech clamp

Mounting the brake discs with aluminium bolts sounds suicidal to me.
Has anyone ever done it and got away with it ?

I’ve run alloy rotor bolts for years, never had an issue, they came with my Hopes IIRC. But there are 6 of them, as opposed to the 2 (slightly larger) caliper bolts.

The two M6 caliper bolts are pretty much in line with the force of the brake.
The M5 disc bolts are a lot closer to the centre so have got a lot more leverage applied to them.
Fair enough if it works for you though. I reckon hollow steel dowels with aluminium bolts would be the best compromise, but would need the hubs and discs machined to suit.

Please tell me you are only replacing these bolts because you want purple anodised rather than plain old steel 😀

Can get coloured TI bolts if you want strong and pimpy, Pro Bolt

If you can live with it falling off, use alloy – otherwise use steel. Also beware of alloy-on-alloy bonding – they can seize completely solid…

Mounting the brake discs with aluminium bolts sounds suicidal to me.
Has anyone ever done it and got away with it ?

**puts hand up**

I use Ashima alloy rotor bolts in my race wheels, which are designed for that exact purpose. Not sure I’d bother again, they’ve got T20 heads and are softer than even ‘normal’ alu bolts (for which Pro-Bolt are excellent – M6 in the mechs, M5 for the lever clamps).

I use ti in my calipers, as I had some anyway, but would use alu, particularly in a post mount. Can recommend Mt Zoom for their ti bolts, good price, and far better quality than Superstar.

Ashima do do coloured steel rotor bolts as well for not much money if you just wanted bling.