Replacing 50T chainring

[Spiderweb]

And one more thing...with a 32t on the back, this bike is mostly great, but on a couple of 16% ramps in cornwall, I ran lut of gear. If I swapped the inner to a 30t or 32t, would that a) make climbing easier and b) would it mess up the rest of the drivetrain set up?

I swapped the inner chainring from a 34t to a 33t, that is the smallest ring you can go to with a 110mm BCD.
https://www.spacycles.co.uk/m8b0s113p1964/SPECIALITES-T-A-Zephyr-110-BCD-inner-33-42t-Chainring

 

[CXRAndy]

Look at sub compact setups
48/32, 46/30, 46/28

Could be nearly as cheap and offer far better hill climbing capabilities. Top speed is only slightly compromised over 40mph downhill

 

[fossyant]

Look at sub compact setups
48/32, 46/30, 46/28

Could be nearly as cheap and offer far better hill climbing capabilities. Top speed is only slightly compromised over 40mph downhill

I'd agree. Top speed isn't really compromised as a 46x12 or 11 is more than enough before you tuck.

 

[Dogtrousers]

And one more thing...with a 32t on the back, this bike is mostly great, but on a couple of 16% ramps in cornwall, I ran lut of gear. If I swapped the inner to a 30t or 32t, would that a) make climbing easier and b) would it mess up the rest of the drivetrain set up?

As noted above the 30 or 32T chainring swap isn't an option - but a subcompact chainset is. But surely, the simplest solution would be a 34T big sprocket. (Rear mech permitting). After all 34/34 is the same as 32/32.

It's that "rear mech permitting" bit that might be the problem. And possibly other things mentioned above that I've failed to appreciate.

Would it make climbing easier? Yes. Not a whole lot easier but a noticeable bit.

 

[si_c]

As noted above the 30 or 32T chainring swap isn't an option - but a subcompact chainset is. But surely, the simplest solution would be a 34T big sprocket. (Rear mech permitting). After all 34/34 is the same as 32/32.

That being said it's always easier to get a larger sprocket on the rear than to replace an entire crankset. Either by replacing the derailleur for one with greater capacity if that's an option or by getting a link extender.

Absolute black do some oval chainrings in 48/32 or 46/30 in a 110BCD which will fit a shimano crankset, but they're not cheap at aroun £150 or so. They do look nice, I have a pair of their round chainrings (purchased during the great bike part shortage of the pandemic as I couldn't get any shimano ones) and they are also quite durable.

Best of both worlds is a subcompact chainset and a low low gear on the rear. My current go to bike has a 48/32 and an 11-34 cassette as I'm overweight and unfit so the gear ratios are very forgiving.

 

[Dogtrousers]

Best of both worlds is a subcompact chainset and a low low gear on the rear. My current go to bike has a 48/32 and an 11-34 cassette as I'm overweight and unfit so the gear ratios are very forgiving.

That's what I plan to do in future when my current 50/34 chainset bites the dust. Or when I just get an urge to fiddle with things, whichever comes sooner.

 

[livpoksoc]

Ok thanks all.

I can get the 34t on the back easy enough. The mech was replaced a couple of years ago to accommodate the jump from 28t to 32t, so should work to go up next time around (that said, there's a brand new 32t on the back dhe to this skipping issue, so it'll be a while).

I have the compact on my n+1 as it's a gravel Giant Revolt with GRX, think that is 48/32. I have a set of road wheels I swap onto this, and the climbing is noticeably easier, and top speed as per other comments is only really an issue on the rare occasion I'm coming back down a climb still pedalling.

 

[livpoksoc]

Just a thought whilst I'm at this - would it be easy enough to replace the LHS crank arm with a suitable power meter crank arm?

Not sure what the compatibility would be. I assume ones listing Uktegra compatibility relate to Shimano only. Would any work with Sram gxp?

 

[si_c]

Just a thought whilst I'm at this - would it be easy enough to replace the LHS crank arm with a suitable power meter crank arm?

Not sure what the compatibility would be. I assume ones listing Uktegra compatibility relate to Shimano only. Would any work with Sram gxp?

Pretty sure Stages do a left side crank power meter - would be around £400. For about £500 you can get a 4iiii Precision Pro 3 which is a full Ultegra R8000 crankset with dual sided power meter. I'd opt for the second one, Stages have had an uncertain future of late.

 

[livpoksoc]

Pretty sure Stages do a left side crank power meter - would be around £400. For about £500 you can get a 4iiii Precision Pro 3 which is a full Ultegra R8000 crankset with dual sided power meter. I'd opt for the second one, Stages have had an uncertain future of late.

Thanks. I was eyeing the 4iii Ultegra ones, but would the left hand side cranks work with a Sram right hand side/chainrings?

 

[si_c]

Thanks. I was eyeing the 4iii Ultegra ones, but would the left hand side cranks work with a Sram right hand side/chainrings?

You'd need the dual sided ultegra crankset option alongside a new bottom bracket, you can't use the ultegra single sided option with the SRAM crankset you already have. Stages do do a SRAM gxp left side, but stages had financial issues last year IIRC so I would be concerned about potential warranty issues.

FWIW I have the dual sided 4iiii power meter and aside from needing two batteries instead of one (compared to the single sided one I also have) it's great.