Gearing on a Giant TCX SLR 1

Thick Mike

Just got the above 2016 model from Pedalon for a decent discount. Before I bought it I was a bit wary of the gearing not quite letting me twiddle up the steep bits of the Chilterns (46/36 and 11/28), but you know...discount!

Anyway, I've had a couple of rides and it's been a bit tough getting up climbs like The Crong, which gets over 16%. Not sure I could manage Bison Hill or other steeper bits.

So, what's the best way of getting me an easier bottom end gear ratio? Cassette would mean 11/32? Would I need to change my RD (ultegra)? Chainrings would be simplest, but the 34t small ring doesn't work with the 46 big ring according to Shimano. (RS500 chainset btw)

trailflow

I am currenty using a short cage DA9000 RD with a 32t casette with no issues. i have to turn the b-screw in more thats all.

Ignore Shimano about the chainring. The difference in shifting of 2 teeth will be almost impossible to notice. An unramped 34t inner ring will shift fine with a 46t. It will be just as snappy. Even snappier than a 34/50t combo.

The cheapest option is a 34t inner. That would be my choice. I recommend a Stronglight Dural chainring.

imposter2.0

'Specialized' TCX - do you mean Giant?

Soudns like you may have mis-read or misunderstood whatever Shimano docs you have been reading. A 34/46 works perfectly well - no reason why it shouldn't.

Thick Mike

Imposter wrote:

'Specialized' TCX - do you mean Giant?

Soudns like you may have mis-read or misunderstood whatever Shimano docs you have been reading. A 34/46 works perfectly well - no reason why it shouldn't.

Sorry, yes...Giant :doh:

Got the chainring info from the tweeks website:

"The chainring teeth have been developed to work in conjunction with HG-X 11-speed chains for increased contact to provide greater efficiency and improved power transfer
Note: Due to the 'shift gate' locations on the chainrings; it is not adviseable to 'mix and match' the chainring options.
The ideal combinations are as follows - 46-36T, 50-34T and 52-36T.
Mixing the chainring combinations will create a less efficient drivetrain."

Just made me wary of combining 46/34

imposter2.0

Thick Mike wrote:

Imposter wrote:

'Specialized' TCX - do you mean Giant?

Soudns like you may have mis-read or misunderstood whatever Shimano docs you have been reading. A 34/46 works perfectly well - no reason why it shouldn't.

Sorry, yes...Giant :doh:

Got the chainring info from the tweeks website:

"The chainring teeth have been developed to work in conjunction with HG-X 11-speed chains for increased contact to provide greater efficiency and improved power transfer
Note: Due to the 'shift gate' locations on the chainrings; it is not adviseable to 'mix and match' the chainring options.
The ideal combinations are as follows - 46-36T, 50-34T and 52-36T.
Mixing the chainring combinations will create a less efficient drivetrain."

Just made me wary of combining 46/34

No idea what any of that means, but I don't think it has any basis in reality. I've been running 34/42, and my lad has been riding 34/38 on his cross bike last season. When the jumps are so small, then 'shift gates' and tooth profiling are largely irrelevant anyway.

Thick Mike

Imposter wrote:

Thick Mike wrote:

Imposter wrote:

'Specialized' TCX - do you mean Giant?

Soudns like you may have mis-read or misunderstood whatever Shimano docs you have been reading. A 34/46 works perfectly well - no reason why it shouldn't.

Sorry, yes...Giant :doh:

Got the chainring info from the tweeks website:

"The chainring teeth have been developed to work in conjunction with HG-X 11-speed chains for increased contact to provide greater efficiency and improved power transfer
Note: Due to the 'shift gate' locations on the chainrings; it is not adviseable to 'mix and match' the chainring options.
The ideal combinations are as follows - 46-36T, 50-34T and 52-36T.
Mixing the chainring combinations will create a less efficient drivetrain."

Just made me wary of combining 46/34

No idea what any of that means, but I don't think it has any basis in reality. I've been running 34/42, and my lad has been riding 34/38 on his cross bike last season. When the jumps are so small, then 'shift gates' and tooth profiling are largely irrelevant anyway.

Great, going to try that option as a first step before looking at the casette.

Thick Mike

trailflow wrote:

I am currenty using a short cage DA9000 RD with a 32t casette with no issues. i have to turn the b-screw in more thats all.

Ignore Shimano about the chainring. The difference in shifting of 2 teeth will be almost impossible to notice. An unramped 34t inner ring will shift fine with a 46t. It will be just as snappy. Even snappier than a 34/50t combo.

The cheapest option is a 34t inner. That would be my choice. I recommend a Stronglight Dural chainring.

Cheers, couldn't see why it wouldn't work if 50/34 is ok on a compact.

Thick Mike

oxoman wrote:

Had same issue with my TCX same model and year and fitted a 34 up front instead of the 36 it came with. Made it better, but will still be looking at replacing rear mech with a medium and a 32 cassette to improve further. The 34 inner ring I fitted was a 10spd one I picked up cheap with the correct bcd even though the bike is 11Spd.

Thanks for that, I don't feel such a wimp now!

Thick Mike

oxoman wrote:

Upgrade update. Fitted 11/32 cassette and Ultegra rear mech and makes it easier on my more hillier off road stuff. How well the chain remains on chainset on really rough stuff remains to be seen. Just need to go to hydraulic brakes at some stage.

I did the same. Plenty of low gears for getting up the steep stuff, or for more technical bits where you need some low speed torque. Though I swapped the small chainring for a 34 too, because I'm a wimp!