Tiagra 4700 1x10?

stumpmagnet

Currently run Tiagra 11-30 and a compact front for racing I use the small ring for cx but the Big ring for the road, I would like to convert to 1x10 but wonder what gearing I should go for as I usually race cx then commute to work the rest of the week and changing tyres and putting mudguards on every Sunday night is enough of a chore let alone changing gearing. So what's a good compromise or isn't there one??

LeePaton

38t Chainring seems to quickly becoming the UK go to.

imposter2.0

As you suggest, there probably isn't one. 38 is certainly a good compromise for cross, but I can't help feeling that the same ring will come up a little short on the road.

VamP

38x11 spins out around 28-30mph so it depends on how much time you spend faster than that really. I have done all sorts of things with a 36t cross rig, including 100 mile sportive and time trials and while there is a limitation, it's not severe.

But! You put mudguards on EVERY Sunday? That would drive me insane.

joey54321

I've got a 38 x 11-30 and it's pretty good. Gets me over most things and haven't spun out on the road and would certainly get my round commuting no problem...might struggle in road races/chain gangs/fast group rides etc...

LeePaton

Could also look at wickwerks and get a tighter chain set

41-36 type vibe?

41 would be good for faster cross races and the road and still have the bail option of 36. I think this will be my combo from now on as 1x wasn't really for me.

Jterrier

I dont think there is a magic answer to this one. You want the bike to do two different things that are quite distinct. Prob go to an 11-32 cassette (is there a 10spd one?) And then maybe a 38 or 40 ring?

stumpmagnet

Yup that's my thinking at the moment

tgotb

Jterrier wrote:

I dont think there is a magic answer to this one. You want the bike to do two different things that are quite distinct. Prob go to an 11-32 cassette (is there a 10spd one?) And then maybe a 38 or 40 ring?

There are definitely 11-32 cassettes; the thing to check would be whether a Shimano rear mech will go up to 32.

I'd advise the OP to take note of which gears he *actually uses* on his commute; do you *really* need something bigger than 38x11?

I spent a lot of the Summer riding around with a 34T chainring and 11-36 cassette, and was surprised how little a compromise it turned out to be. I only really span out going downhill, which wasn't a problem in the event I was preparing for. 38T would have eliminated even that issue (but my need for a 34x36 combo was greater...)

robertpb

As you are already doing a lot of swapping over why not go for a 11-32 with two different chainrings to suit and two chains to fit.

I have a 11speed with 10-42 and 38t for MTB trails but if I switch to more road a 44t.

stumpmagnet

A spare crank would be easier that's what I'm thinking now

prawny

Blimey I struggle to bother checking my tyre pressure and lubing my chain ready for a monday commute, that sounds like waaaaay too much trouble.

How far is your commute? Would a 2nd hand cheaper bike not be a more time efficient use of cash? Plus you'd save wear on your race bike.

stumpmagnet

My commute could be 3 miles but I do a 20 mile loop each way. (I'm not sure why either!).
wear doesn't worry me as I clean and maintain my bikes fastidiously and a cross race every 2 or three weeks is no bother to swap every thing over. If stuff wears out I replace it.
I can't justify having a sole bike for cross as it's too infrequent and only for a quarter of the year so to use it as a commuter and winter bike/cross racer means I get more bang for my buck
I have a summer best bike (ribble R872) while my crosser (ribble cr3) is a bit of a slug by comparison with mudguards and 28mm tyres lights saddle bag etc
Believe me if I could I would love a cannondale super x or spesh crux or ridley or something just sitting there for the odd weekend cross race but I can't justify it to myself or the boss (wife). Maybe next season then keep the cr3 for commute and winter.only.
Anyway I have a plan a friend has a spare 36-46 FSA cx chainset i can have so I will replace the BB to take the FSA then use BB conversion shims to take up the size difference for the smaller tiagra crank axel should only take a few mins to swap

trek_dan

Why are you so keen to convert to 1x when it sounds like a double would suit your needs perfectly? Plenty people still use double for CX racing.

Chris James

trek_dan wrote:

Why are you so keen to convert to 1x when it sounds like a double would suit your needs perfectly? Plenty people still use double for CX racing.

Including the last two world champions!

Running a front mech massively reduces the chance of dropping your chain too, and if it does happen you can pedal it back on. Obviously the mech can also act as a mud shelf so it is a all swings and roundabouts, but even though single rings are very fashionable at the moment it isn't as if there is a clear advantage either way.

stumpmagnet

yes in my last post i said 36-46 as i also think now a double would suit me better just not a compact 34-50 but would like both so i can swap from road to cx

Chris James

There isn't much difference between 46/36 and 50/34. You currently race on the 34 ring - does this cause you a problem? I must admit I rarely use my 46 ring except on the road. My top gear on the crosser is 46/12 and I am fine with that, it's not like I am doing time trails on it.

Do you use your current bottom gear, as you would lose that by moving from a 34 to a 36 inner ring? If the two chainsets are the same BCD then you could consider fitting the 46 outer to your current chainset and losing two links in the chain. 46/11 is still a pretty big gear at 110 inches - about what Cav and Brad would have used to win the Madison Worlds.

stumpmagnet

cant seem to find a 46T outer ring for the new tiagra 4700 chainset theres a 105 CX set for around £60 though sod it ill leave it alone just treat the big ring as a chain guard and the front mech as a chain keeper