Which Groupset?

I've had enough of your anti-FSA agenda @dubtap - I'm writing a stern letter to you Shimano paymasters.

My search skills fail me, but I'm pretty sure older Rival shifters had a tendency to fail in the shifting mechanism - I know mine did - but that the problem was fixed in later generations. Is there any way to tell if a pair of shifters are of the new or old variety without opening them up?

@JesperXT are you talking about the 10speed versions? I think they changed the graphics on the brake lever blades each generation, also the doubletap lever changed from grey to black at somepoint...

Yeah, 10 speed. If only SRAM would supply spare parts...

@JesperXT they do don't they? I've ordered spares in the past through LBS and, would you believe it, Tesco direct!

Internal shifter parts? I've tried, but with no luck anywhere.

maybe try East Central Cycles - 020 7837 0651

not sure about smaller springs and ratchets but I think you can get the whole mechanism and lever blades...

Weighing-up the options for a SRAM 1x10 or 11 group for a TT bike that is currently Shimano 2x11.

I understand that SRAM cassettes will fit a Shimano freehub, but am I right in thinking that they are differently spaced, on account of the 1:1 cable pull (Exact Actuation)?

SRAM lists the regular 500/900 aero shifters as using EA, but not the R2C shifters: seems odd, is this right? If so could I use R2C shifters with a Shimano cassette?

The reason I'd like to use a Shimano cassette, is because this would allow a Power Tap to be shared with two other Shimano 10 speed bikes, without having to swap cassettes.

Assuming I can't get SRAM to work with the Shimano bikes, what options do I have for a Shimano RD with a clutch?

all 11 speed cassette spacing (including campag - although their spline/freehub is obv different) is the same.

Its the mechs/shifters where the difference in cable pull is important.

So Shimano 11 speed cassette will work fine with Sram 11 speed mech/shifters

Also - I wouldn't bother with a clutched mech on a TT bike

Thanks.

Ideally I'd like to go 10 speed to save swapping out the cassette, when moving the PT between bikes.

Looks like I'd have to stick to Shimano to do that though.

Also - I wouldn't bother with a clutched mech on a TT bike

Not even with a single ring up front?

Seems like the best option as it cures the problem (chain slap), rather than treating the symptoms (N/W ring or a chain guide).

Was assuming you would use a NW ring.
I have a feeling clutch mech's may have higher frictional losses than regular mechs as well.

Reading the 1xn thread on TTF, not everyone is sold on NW rings: Stephen at Fibrelyte in particular.

Either way, it would limit the choice of rings somewhat (was thinking of a Fibrelyte full aero ring) and it doesn't solve the problem of chain slap.

I didn't know about the extra drag with a clutched mech though: I'll have to look into that.

I understand that SRAM cassettes will fit a Shimano freehub, but am I right in thinking that they are differently spaced, on account of the 1:1 cable pull (Exact Actuation)?

The spacing on 10 speed Shimano and SRAM cassettes is the same. SRAM mechs and shifters have different cable actuation ratios, so you can't mix'n'match shifters and mechs, but the net result is the same amount of movement per click at the derailleur.

That's good news: in theory, that would allow the Power Tap to be used on all three bikes, without swapping the cassette.

it doesn't solve the problem of chain slap.

Is this a problem? Are you planning to use an 11-34t or something?

Not that large, but without a front derailleur or keeper and with the state of the roads around here, I don't want risk losing the chain at full tilt!

Don't lean.

I had to think about that.

I shouldn't have bothered.

#groan

Let's solve one problem at a time tho innit.

Your NW (or tall-tooth-ring+dogfang combo or chain guide) will keep the chain on. Sorted.

Is chain slap a problem? No, because your not using a massive cassette range or a small ring. So no clutch mech needed. Sweet! :-)

OK, thanks.

Is there some method to guess-timate the likelihood of a slap?

using a massive cassette range or a small ring.

^ these things don't help.

Don't know if this is the correct place to post, but it's concerning the front mech of my Chorus 11 speed groupset.

It won't change to the big ring. Increasing the cable tension results in the mech popping back to the second 'click' after shifting 3 clicks upwards (if that makes sense). High limit screw is set so the mech is as far from the frame as possible.

Any ideas? Could I maybe try to position the whole mech more towards the outside? Kind of my first time setting up a Campagnolo groupset/mech.

Cable not tighten at the correct direction.

Check instruction and video if necessary to see where the cable should route through for optimised shifting.