Quick rear derailleur question :-)

[Pat "5mph"]

What are you planning to climb @Pat "5mph" , a 34T with a triple chain wheels will let you climb a vertical wall but it will be very very slow, you might be better going for a 32T, I have 11-32 with double chain wheels and it is more than adequate for the very hilly terrain round these parts.

Forgot to answer this previously:
I'm not planning to climb much (maybe Arran , I already did a bit of Arran on this bike) but because there was the choice of 32 or 34 on offer I though why not, I'm slow anyway, cannae get any slower!

 

[lutonloony]

26x34 you'll be doing 1mph up those hills

That's probably 3mph more than I would do

 

[fossyant]

The 4601 GS has a 32T capacity.

Are you finding the 26x30 problematic climbing.

 

[fossyant]

You will be going exceptionally slowly in those gears and might actually make it harder to control.

 

[Pat "5mph"]

The 4601 GS has a 32T capacity.

Are you finding the 26x30 problematic climbing.

On a 14 kg bike carrying the kitchen sink sometimes hills are a challenge... that's my excuse ...honestly, I would be pants at cycling even on a 5kg carbon
It's great you tell me this info Fossy, because the 32 is on offer too.

 

[Pat "5mph"]

You will be going exceptionally slowly in those gears and might actually make it harder to control.

Got a 32x22 on my Pinnacle, was ok on the Lakes tour we did in the summer.
Only walked the Kirkstone pass

 

[Scoosh]

Balance becomes tricky at 1mph ... even with a kitchen sink slung around the bike.

Someone very smart will come along and tell you what gear inches/centimetres you would have with a 26/32 and 26/34 on a 700c wheel This is the distance you would travel with 1 revolution of the pedals. You don't want to be flailing around doing 5 inches at high revs when you are only going at 1mph ...

 

[Pat "5mph"]

You don't want to be flailing around doing 5 inches at high revs when you are only going at 1mph ...

This is double Dutch to me
Anyhow, according to Garmin I routinely do 5mph or under on what a normal cyclist would consider mere inclines, low gears won't make me fall off

 

[Ajax Bay]

With a Tiagra RD4601, the jockey wheel will interfere with the largest (34t) sprocket. This is even with the B screw right in. You might just get away with a 32t.
The RD's capacity limit (on a triple 48-26-26) means that the RD will not wrap sufficient chain so if you run a chain which is long enough to go large to large plus a link (1") as is recommended, if you go small to small the return leg of the chain will foul the lower part of the cage. Be careful whose advice you take and also be aware of confirmation bias.

 

[Pat "5mph"]

Be careful whose advice you take and also be aware of confirmation bias.

I've no bought anything yet: shall I get the 32 then?

 

[fossyant]

Stick with the 30.

 

[Ajax Bay]

Pat
There have been a number of cc threads which discuss whether a 32t can be coped with, and the consensus is, iirc, "just".
You still have the capacity problem because whereas most are running a compact (50-34) which takes up 16 of the capacity, you (and I) are running a triple, which takes up 22 (48-26). So when you add the 19 of an 11-32 you're asking the RD cage to wrap more than it can. If you can get a 12-32 that would be 1 better and you assuredly do not need the 11t. In fact a 13-32 would be fine too, but you can't buy them.
https://www.cyclechat.net/threads/shimano-medium-cage-derailleur-capacity.203463/

 

[Pat "5mph"]

Stick with the 30.

Ok

 

[Pat "5mph"]

If you can get a 12-32 that would be 1 better and you assuredly do not need the 11t.

Ok, I will get Googling again and buy whichever I can find cheaper.
Cheers again for all the answers: it's only because I read the mechanics forum that I am aware of a possible issue, it's brilliant there are so many competent members on here!

 

[Scoosh]

This is the distance you would travel with 1 revolution of the pedals. You don't want to be flailing around doing 5 inches at high revs when you are only going at 1mph ...

This is double Dutch to me

What it means is that you don't want to be moving forward 5 inches for each pedal revolution and only going at 1 mph.