I guess that I’m a bit of an oddity pootling around on a fairly portly rigid Singular Swift as a sort of flat bar gravel bike. I’m also low income so have had to recycle kit from my 26er and am currently riding it with an ancient (now on its 3rd or 4th bike) XT Octalink triple with 44/32/22 at the front and 11-34 out back.

I’m thinking about modernising and looking at options. One problem I’m coming across is finding something with the right high gear; my 44 tooth big ring is fine although I think that a 42 or 40 would be ideal (although I realise that I’d probably learn to ride with something different). Shimano’s current crop of doubles have 38/28 as the highest option; when I search for 42/28 chainsets I get loads of hits for SRAM X5-X9 chainsets but they seem out of stock in the UK and Europe (despite still showing as current on the SRAM website).

I also noticed that SRAM have a Rival chainset with a 42 tooth single ring option, but I’m guessing that this would be messy on a bike with a 135mm rear hub; the Rival runs on a 45.5mm chainline whilst 135mm spacing seems to work with chainlines around the 50mm mark (I’m a bit vague here so might be talking guff).

The other consideration would be that the kit would need to be viable for some years to come so I’d need to be able to get hold of chainrings; there seem to be a variety of BCDs and I’m not sure how easy sourcing rings might be in the future.

So, what are my options (not too pricey please) and would I learn to accommodate the 6 tooth difference between a 44 and a 38?

I did the same thing recently.

Cheap crankset

http://www.chainreactioncycles.com/jp/en/shimano-fc-m4000-alivio-octalink-chainset/rp-prod162762

Cheap cassette

http://www.chainreactioncycles.com/jp/en/shimano-alivio-hg400-9-speed-mtb-cassette/rp-prod119945

I’ve just assembled a sort of Bastid “Sub-compact” 40/22 double using an old (104/64BCD) MTB crank, intended for touring/commuting/gravel stuff…

Just about everything you read says that the maximum difference between chainrings should be 16t, so I’m willing to bump the granny up to a 24t if an 18t gap really doesn’t work, it will probably get used with an 11-28 or 11-32t, 8 or 9 speed… just keeping things cheap and cheerful.

The plan is that day to day it just stays in the 40t the 22/24 granny is there really as a full on bailout gear so if I’m lugging a bunch of stuff and encounter a big hill I’ve got an appropriately silly low ratio.
TBF it’s really not going to be a million miles away from the sort of drivetrain I had on my MTBs 15-20 years ago…

Another triple wouldn’t be a problem, but again most modern triples have a 40 tooth big ring and I could get the ratios I want in a double (or even a single) with a 40 or 42 tooth ring.

I’ll have a look around and keep an eye in the classified in case anything interesting pops up.

Again, being able to keep getting replacement rings would be important.

If it’s an old octalink crank, does that mean you’re tied into the shimano direct mount chain ring?

If that’s the issue and you want to future proof ring selection, why not use a second hand holllowtech triple? I’ve got spares kicking around from Deore, through XT, up to XTR.

Surely 2x trends mean there’s plenty of those available.

If it’s an old octalink crank, does that mean you’re tied into the shimano direct mount chain ring?

It just uses standard 4 bolt 104 BCD 9 speed chainrings (I’ve got a mix of Deore and XT rings on at the moment) although I think that Shimano tweaked the design slightly when moving from  HT1 to HT2 meaning that HT2 middle rings don’t fit.

I can probably find a suitable triple or double, when the current one gives up,  if I look around.

I think that Shimano tweaked the design slightly when moving from HT1 to HT2 meaning that HT2 middle rings don’t fit.

Rough Bastard might be helpful with that.

I found this link earlier: https://www.cyclingabout.com/wider-gear-range-road-shifters-gears-for-easier-hill-climbing/ which might be relevant.

There’s some interesting ideas for touring/gravel type drivetrain setups there, both doubles and triples and the article is mainly discussing overall range and lowest gear capacity.

Obviously they’re talking about drop bar shifters/STi but the drivetrain options will be equally applicable to a flat bared bike, There are some nice looking options for “Sub-compact” chainsets about now…