my tour de fer has a 50/39/30 tiagra chainset with a tiagra rear mech.
gearing is too big for me. i like to spin.

a mountainbike chainset would be more suitable. will it work with the rear mech and shifters.

i think it will, just want to make sure

Swap cassette? An extra tooth on the back is two/three off the front. What’s on there at the moment, a 28 or 32? If not the latter, there’s your answer.

@TiRed, big heavy bloke on a touring bike. Thinking 22/32 bottom gear is more the target than 30/32

Shimano do what they call a mtb touring triple chainset in the deore range thats my weapon of choice its something like a 26 36 48 great for steep hills spinning and with the 48 can’t blame spinning out for not keeping up when out with pure road people

I guess assumes threaded bb

Shimano do what they call a mtb touring triple chainset in the deore range thats my weapon of choice its something like a 26 36 48

Same on my tourer, it’s spot on with a 11-32 on the back.

The rear mech (long cage?) should be fine, front mech might need some fiddling to work well. I have a Sora triple front on my tourer that’s fine with a Stronglight triple starting at 24t.
You might need to look at chain length too.

Standard Shimano MTB triple chainline is 50mm, whereas Tiagra has a road triple chainline of 43.5mm, so a 6.5mm difference, which might not work well with the front derailleur.

I think it might be theoretically possible to fit smaller rings to the Tiagra chainset, since it has sufficiently smaller bolt circle diameters, but (and depending on whether 4 or 5 arm) I think you would struggle to find the rings you want, unless you went for Stronglight or TA rings, and the outer ring would probably look out of place.

I suspect the simplest option would be to buy one of the various road triple chainset options offered by Spa in square taper format, and fit a UN50 series bottom bracket.

I suspect the simplest option would be to buy one of the various road triple chainset options offered by Spa in square taper format, and fit a UN50 series bottom bracket.

This for the hassle free answer, will probably go down this route when I get round to swapping my flat bars for drops on my vagabond as STI’s probably won’t work with mtb triple on there at the mo

Despite being told what I needed was 1*10 with a wide range cassette on here

I fitted a deore touring and relevent mtb front mech to my Kona rove (using claris Sri units)

Took me and my 40kg bike over some 2000m passes in the rockies and 2000km of riding in Canada no sweat.

And anyone that says 48 ain’t big enough/they will spin out etc. We were cruising with a tail wind at a steady 25mph on the last day and I wasn’t even in the 11t.

I ran the deore touring chain rings on my xt chainset. They seemed to last forever. I don’t think I had the energy to spin out in 48t

https://vgy.me/3nF6lz.jpg%5B/IMG%5D

Pic for testing purposes but that’s my tourer 🙂

Another Spa user.

I went for the budget crank with the Zircal rings, supposed to last for ages.

24/36/48, with a 105 front mech.
Perfect with a 36 cassette.

Looks nice too.
🙂

I had to do a similar conversion recently for my and my partner’s bike. She had a Tiagra Triple like yours. I fitted the smallest granny ring I could (24T I think) and a 11-34T cassette at the back. I had to set the limits to prevent shifting into the 50T ring though as there would be too much chain for the long cage mech to cope with when in the 24T ring. This left a 24/39T Double setup.

On my bike I had a single ring crankset. I bodged on a Mtb tripple chainset with only two 22/38T chainrings fitted. It needed extra spacers on the non-drive side of the BB to make it work as mtb cranks are wider than road ones. Chainline was fine but the above option would be better.

This worked for us while ladden touring for 3 months, 5500km and 55000m of climbing. Didn’t walk any hills either! You don’t need the big rings anyway as you’ll rarely get to a speed that they are useful.

thanks for all the ideas everyone. I have a new deore chainset, I will try that to start with. fingers crossed.

Another Spa user.

I went for the budget crank with the Zircal rings, supposed to last for ages.

24/36/48, with a 105 front mech.
Perfect with a 28 cassette for wide range but close gaps

Looks nice too.

Yup.

I fitted an XT 22/32/44 chainset to my TDF. Wasn’t convinced that a road mech / shifters would play nicely with it so went with an XT mech and barend shifters. I have a 22×32 lowest gear and without it I’d have been stuffed on more than one occasion.

The Spa Cycles option looks like a good one. I’m really hoping that Genesis spec the Tour de Fer with touring gears for 2018 as 30×32 really isn’t a sensible option for anyone other than a strong rider for loaded touring (which the bike is designed for!)

Fer with touring gears for 2018 as 30×32 really isn’t a sensible option for anyone other than a strong rider for loaded touring (which the bike is designed for!)

Shhhhhh don’t tell my wife. She smashed it in 30/32 on the same ride. I had to swap mine out as it was a compact double with a 28 out back

I’m really hoping that Genesis spec the Tour de Fer with touring gears for 2018 as 30×32 really isn’t a sensible option for anyone other than a strong rider for loaded touring (which the bike is designed for!)

someone asked me how I was getting on with it. I like it, but it seems more a audax bike than a touring bike.
I still think the best touring bike is the Surly disc trucker.

I’ve got a flat bar Tour de Fer that I built from a frame set.
I’m basically running full 9sp MTB gearing, so 22/32/44 and 11-34 cassette with a mix of XT, LX and SLX components with a SRAM X-Gen front mech (the toughest front mechs ever made IMO)
Whoever thought of speccing a touring bike with a 50t outer should be shot really. They did the same with my CdF as well, which I immediately swapped for a 46.
Bikes like this don’t need such high gearing. If I was building a drip bar TdF I’d still go 9sp. The new Sora shifters are lovely and afaik they’ll work fine with an MTB drivetrain (do they do a triple shifter though?)
Triples and 9sp FTW on a touring bike! 🙂

2000m passes in the rockies and 2000km of riding in Canada no sweat.

Love to see some pics from that TR

I modified my 105 crankset from 50/39/30 to 50/39/26 which worked fine with the 105 front mech and STI shifters. I’m running a 10sp 11-34 on the back with a Deore 9 speed mech. This gives me 26/34 as the lowest gear on my Vaya. I’m debating about swopping the crank to a Spa one so I can go lower on the front, but I’d have to learn how to ride slow speed without wobbling first 🙂

Pickers , will do a post later in the month . Been too busy since i got home to contemplate sitting infront of a computer …..

But im off to work for 6 weeks now so should find some time insbetween destroying the exercise bikes.

The new Sora shifters are lovely and afaik they’ll work fine with an MTB drivetrain (do they do a triple shifter though?)

Yup, they do a triple, stock fitment on the base AWOL.

I’ve got 10spd triple 105 brifters, XT 9spd mech, 105 front mech, 12-28 on the back and 24-36-46 (I think) from Spa on the front. Works lovely.

interesting discussion, i’d been wondering similar. my thinking was 26/36/36 with an 11/32 on the rear for general tinkering about riding, though i have wondered about 22/32/42 to make life incredibly easy and i can see that option for loaded touring with hills.

how is the 39 for cruising? if ok you should be able jut to stick a much smaller (24 miniumum size) granny on.

if the 39s no good then lookinto swapping chainsets imo.

30×32 really isn’t a sensible option for anyone other than a strong rider for loaded touring (which the bike is designed for!)

Tourers definately need nice and low gears. I did a wee tour of the West Coast of Scotland a few years ago on my Genesis Croix de Fer with its original gearing (34×25). Rather than a leisurely cruise it felt like a ferry to ferry time trial each day.
Lesson learned for next time. 😆

TR – cheers, look forward to that.

simondbarnes – Member
The Spa Cycles option looks like a good one.

Square taper and the fact they do 165mm swung it for me.

Think it ended up about the price of an XT crank.