Which Groupset?

Thinking about mechanical Dura Ace with discs for my upcoming build. Are the Shimano road discs only available centrelock? Hard to pin down the exact specs for a lot of the disc stuff.

Only Centrelock I believe.

I thought that too, but Skinny's wheel is here with a 6 bolt disc that's being used with Shimano hydro?

Or am I missing something?

Or is this question only applicable to non hydro Shimano road discs?

Yes you are, those are the standard MTB one, the road one with cooling fin are centrelock only.

MTB ice tech rotor work perfectly well.

Looks like you can get the 160 mm in 6 bolt. Hmmm. Road seems to be adopting 140mm as standard from what I can gather.

Do you mean the actual disc rotors? Or is your question more along the lines of 'can I use 6 bolt discs with Shimano calipers?'

Well the original plan was King R45 disc hubs and Shimano discs but it looks like the 140mm are only in centrelock and I'd need the 6 bolt fitting to fit the King hubs.

You can get non Shimano 140 disc rotors. It'll work still.

As far as I'm aware the only Shimano rotors you can't get in a 6 bolt fitting are the RT99 'Freeza' discs (originally part of the XTR group) which have the cooling fins in the inside of the disc. Like this:

They're only available in Centrelock fitting regardless of size.

Cool, yeah I was thinking that option could be available. Are rotors a uniform thickness nowadays? I'm a few years removed from my MTB days.

The thickness is close enough that they're all compatible. Except for the vented ones.

I use Hope rotors with my R-785, in 160 front/140 rear, works perfectly.

Good stuff, may take that route. For reference, can you tell any difference between the rotor sizes and braking power/modulation?

I've not tried different rotors to the ones I currently have on the bike, but with other bikes I have found that 160 on the rear was maybe toward the overkill end of the spectrum - 140/160 seems to be nicely balanced.

I like having a lot of power available at the front - my ENVE RD fork is setup for a 140, but I used an adapter to step it out to 160.

After 3 years I have finally sorted my woeful Sram Apex front shifting bike on my commuter/winter by the simple method of replacing an Apex chainset with a Shimano CX50 one. This trend may continue

I have found that 160 on the rear was maybe toward the overkill end of the spectrum.

Me too, especially when it's very easy to modulated the rear brake.

140mm would be ideas.

Whats the hardest longest lasting 10 speed Shimano fit cassette?

If Tiagra is good enough for Steven Abraham (and £12.49) it's good enough for me.

I'd just go for the cheapest which is as you said Tiagra.

Make sure your freehub body is steel, otherwise the cassette will dig into the alu body.

Shimano CX50 crankset including bottom bracket, 105 chain and Tiagra cassette and you get change from £75.00. Mental.

Put that in your spreadsheet and smoke it

Where did you find the CX50 that cheap? the Tiagra crankset is usually the best bang for the buck at around £45.

^Planet X for CX50 and Tiagra BB (not mentioned in the listing) £49.99

Very good deal.