Caught out by the Shimano 10 speed tripwire, a warning !

[Flick of the Elbow]

I needed a new rear mech for my 105 10 speed shifters. Shimano’s only 10 speed group is now Tiagra. So I duly bought a Tiagra rear mech from Wiggle, fitted it, but couldn’t get it even close to indexing properly. Took it to my LBS who took one look at it and told me that every mechanic he knows has been caught out in the same way. The current Tiagra 10 speed uses a cable pull ratio all of its own, it’s not compatible with anything other than itself. So if you need a replacement 10 speed rear mech your only option is to find some ever dwindling old stock of 105 10 speed. He did offer the thought that dropping down the groupset range another step to Sora might work too, he thought that 9 speed Sora might use the same ratio as 105 10 speed. Can anyone confirm this ?
Meanwhile with a spot of googling I have indeed found an online supplier with a 10 speed 105 rear mech, I’ve just ordered the last one they had in stock.

 

[T4tomo]

its old news but worth repeating.

The 10 speed 4700 Tiagra shifters use same cable pull ration as 11 speed Shimano - so you can use higher group sets RDs with them.

In you situation you are looking at NOS 10sp 105 or yes 9 spd Tiagra / Sora mechs will work, and anything from micro-shift 10spd range will also work very nicely with it (and possibly cost you less). I went that route when some 9spd shimano shifters failed - got10spd microshift shifters and changed the cassette.

 

[Venod]

I run new Tiagra brifters with a GRX400 deraileur works fine.

https://bike.shimano.com/en-US/info...and-matching-shimano-grx-and-road-compon.html

 

[fossyant]

Older Shimano 8-10 speed mech's use the same ratio except ONE. Dura Ace 8 speed (7400) is only compatible with itself.

You could always buy new/lightly used old stock from ebay.

 

[Drago]

Tiagra has used a different pull ratio since it went 10 speed some years ago.

I actually really like it, because the longer throw at the Tiagra lever suits my big hands.

 

[Sharky]

Have browse on SJS Cycles for Jtek shift mate.
No experience of them but good reviews.

 

[fossyant]

Anyway, we've missed the biggest sin here. The OP is 'downgrading' components. OMG !

 

[Flick of the Elbow]

Have asked for a refund from Wiggle. And have also asked that they note the incompatibility issue in their product details section. Not holding my breath on either count.

 

[figbat]

Tiagra has used a different pull ratio since it went 10 speed some years ago.

I actually really like it, because the longer throw at the Tiagra lever suits my big hands.

I thought that 4600 was "normal" pull ratio but 4700 went all selfish? I use a 4600 10-speed brifter with a 9-speed XT derailleur to good effect.

 

[Rooster1]

The Tiagra 10 speed brifters are crap. Nothing but problems with the cable not pulling back in on shifting, and then jamming. And my rear mech corroded after one year (4000 miles) and lost its "spring". This morning, for the fifth time this year the bike is off the road - just before the weekend.

 

[figbat]

In contrast the Tiagra brifters on my road bike and gravel bike have been nothing but reliable, as has the Tiagra RD on the roadie. These are 4600 if it makes a difference.

 

[Smokin Joe]

I found Shimano road stuff to be a bit fragile, I bitterly regretted switching from Campag.

 

[DCBassman]

Due to a fault, I recently replaced a a Sora GS with an Altus SGS. Quality of shifting?
Unchanged.

 

[Fab Foodie]

I found Shimano road stuff to be a bit fragile, I bitterly regretted switching from Campag.

…and I’m not shifting from 9 speed!

(See what I did there?)

 

[Drago]

I thought that 4600 was "normal" pull ratio but 4700 went all selfish? I use a 4600 10-speed brifter with a 9-speed XT derailleur to good effect.

Oh, in that case there may have been a bit of overlapmof which I wss hitherto unaware.

I found Shimano road stuff to be a bit fragile, I bitterly regretted switching from Campag.

Commuted on 105 for nearly a decade, all you round, all weathers, found it agreeable tolerant of filth, utterly dependable and very robust. Even the parts with a bling finish survived well.