There are some courses where 36/11 might not be enough. I use the big ring a lot say at Margam, coming down the last hill. Of course, a lot of people just coast down there… 😉

It's not sufficiently big that you'd spin out 36/11, it just isn't. Maybe the very top bit on the grass you'd be using it, same with the bottom bit, but not spinning it out.

You would spend a lot more time down at the bottom of the block with a smaller chain ring though, cassette would wear quicker.

I said I use the big ring, not that I'd spin out 36/11 🙂 Part of it is that if you just lose the big ring, the chain line could well end up less than ideal in 36/11. Hence why I use the big ring.

I'm sure I've used 46/11 in races on downhills. Quite possibly on Margam. Definitely 46/12 or 46/13 tho.

Do you still use a std front mech for 2×9?

Fair enough, I used to use a 48, back in XTR M952 days. I used to go whole races without using it! No way I'd even consider a 46 myself.

Chain line should be alright in 36/11, like I say though I'd just be thinking about the cassette wear.

40 in the middle at the front, and a 26 inner ring

Me too, although just a regular trail hardtail – I'm not into racing at all. Combined with a 34-11 cassette it works well for me, although my reasoning for changing was to fit a chain device, not to save weight.

I'd like to find a 38t ring for my full-susser though as 22t and 36t at the front aren't enough for me.

Do you still use a std front mech for 2×9?

I do, just use the limit screws to control mech movement range.

TA do 38t rings.

I used to just use a conventional triple front mech, have also tried Dura Ace, now got an XX one, they all shift fine!

I notice the Middleburn duo doesn't do well here! Would it better as 4/5 arm triple with the appropiate chain rings to run as a double?
The XTR set is pricey with buying extra rings on top!

You can convert any chainset you want in the same way as described for the XTR, Deore or SLX would work just as well.

Bear in mind you can sell the OEM XTR rings though, I bought an XTR chainset from Merlin for £250 and sold the rings for £140, by the time you've bought rings it's only about £160 or so for a very light chainset.

Thanks guys, I've taken the advice and just popped the rings from the garage on (ok well my husband has as I had to feed the baby), so I'll be giving 26/36 a whirl.

The bike is coming together nicely now. Just need to pop the chain on and index the gears (and get some decent tyres) and it'll be ready to ride! (The rider needs a lot more work mind!)

Btw, Njee, I am intrigued – how come a front mech will shift better with a 12t gap?