I have an Ultegra 50/34 Crankset and need more lower gearing. Can I change the 34t for a 32t with out having any issues.
11/32 Cassette and 50/34 crankset. Not sure if changing out the 34t for a 32t will cause any issues when shifting.
Thanks

Which Ultegra? Not that it matters, it's not possible to put a 32 on either 6800 or 8000. Nor any of the earlier series. It also surpasses the max difference between chainrings spec'd by Shimano. It would shift ok, not great.

So I would need to go with a new crankset 48/32?

You could go with a cassette with a bigger spread on the cogs, example 36T. But, unless your present derailleur is a GS, not SS, that would mean changing the rear derailleur. What speed Ultegra do you have? Obviously, a 9 nine speed set up with long cage gives you a wider gap between the gears than an 11 speed system. Some cassettes are not readily available right now.

Spec's are HERE if you've not found them.
Large limits are 46-53T with 16T capacity.

Shimano has R8000 crank available in 46-36T
I do wonder why Shimano dropped to 46T but only used 10T capacity offering 36T


Hope that helps

Barry

Your real problem is the BCD of our crank. I believe it is 110mm so you can't install anything less than a 34t. Well, I think technically 33t, but finding that is pretty much non-existent.

What I think you should do is run the ratio/speed numbers to see what advantage you will get from going to a wider range cassette and a longer cage rear derailleur, or swapping the crank to a 46/30.

I think a lot of people see a couple tooth change as their saving gear ratio and then find it is not as significant as they had hoped for. Running the numbers, especially with a cadence/speed calculation, may help you get a feel for how much benefit you will gain.

John

I have an 11 speed with medium cage derailleur.

Thanks John, that may be a better option if I can find a 11/36 cassette.

The medium cage will work with a 36T just fine. If you think that is not enough additional low gearing, a 46/30 crankset could be the way to go.

SRAM makes an 11-36 11-speed cassette that I've used on Ultegra 6800 (with a Wolftooth Roadlink) on my gravel bike. Gives you a good bailout gear for long climbs.

Yes. There is no way 32 t will clear the 110 mm bcd.

You don't know this. OP still hasn't said exactly which GS derailleur he has. The 6800 will work w/ a 32, the 8000 a 34. I'd normally be comfortable w/ using a 36 w/ the newer 8000 derailleur, but not necessarily the 6800.