jjay03

I have a new Domane SL5 with the 11-34t rear cassette and 50/34 compact crank. I ride mostly on flat bike trails and dont ever really use the largest sprocket on the rear cassette. What gearing would you recommend? I was thinking about going to an ultegra 11-30t rear cassette.

If I swapped out the rear cassette HG700-11 to a CS-r8000 11-30t would I need to change anything else? Still use the same rear derailleur? I was also thinking about going to an ultegra chain at this time.

What tools should I buy to remove/install the rear cassette?

Thanks

Iride01 

Shimano has a whole big chapter devoted to the tools needed on page 6 of the DM for the CS-HG700-11.

https://si.shimano.com/api/publish/s...001-03-ENG.pdf

You can find a generic lockring tool from many different sources. Though if this is a onetime change or something you'll do rarely, then let the LBS do it.

Though you'll probably need to shorten your chain too.

jjay03

I could have my LBS do it but I like to have all the tools to work on my bike myself and enjoy doing it. Thanks for the link.

jjay03

I just found this video as well for the park tools.

Iride01 

Park Tool makes some pretty good videos. They should be your most trustworthy video over most any youtuber out there making vid's. However some component manufacturers have their own vid's too and you should look for them also when needed.

I have seen some of the best produced vid's with a well spoken seemingly knowledgeable person on youtube give the worst possible information about how to fix something. So when doing something new, don't just go by the first video you find.

And if it's a Shimano component, go to their tech doc site and look at the info on it. DM 's are best if they have them.

I change my cassettes without having to need a chain whip, but admittedly it will be less trouble sometimes if you have one. An old chain and you can make your own.

SoSmellyAir

You need at least the lock ring socket and a chain whip. You may also want a torque wrench, but if you do not have one, this video shows how to tighten the lock ring to the correct torque:


Yes, the 11-34 cassette sucks, especially if you mostly ride in the flats. Before you buy a replacement, see if you can also ride without using the next two largest cogs (27T and 30T) in the 11-34 cassette; if so, a 12-25 is the way to go for minimizing the disruption to cadence from shifting. You do not necessarily need a new rear derailleur for a smaller cassette; you just need to loosen the B screw (by a lot), and shorten the chain appropriately. Although a short cage derailleur can theoretically shift a small cassette faster, I doubt you would notice the difference in practice.

To shorten the chain, you need a chain tool (CT-3.3 Chain Tool | Park Tool) and mostly likely also a pair of chain pliers (Amazon.com : Super B 2-in-1 Master Link Pliers (The Trident) : Sports & Outdoors).

jjay03

Thanks. How do I know how long to make the chain. I was also wondering if I could go up to a 52/36 on my crank. I want to go with a power meter crank anyways. I watched videos on the cassettte, rotor, and crank removals which all seems pretty straight forward. I do have multiple torque wrenches as well.

I will pay more attention next time to what rings I use. Im pretty sure I mostly use 3 or 4 rings at the most. I will shift down to the small ring in the front when stopping of course.

aliasfox

I've been riding a lot of rail trails this year, and have come to the same conclusion - the 11-34 (HG800, in my case) has a lot of gears at the top end that I don't use. But the 11-28 or 11-30 don't actually solve my issue. Next time you ride, check to see what gears you're actually riding in. For me, I'm usually in 50x17, 50x15, or 50x13, and I often crave that 16t or 14t that I don't have. Problem is, the Shimano 11-28 and 11-30 don't actually have those cogs either - instead, they add in a 12t (fairly useless to me), and make the climbing gears tighter (also, not particularly useful to me).

My solution was to get the SRAM PG-1170 in 11-28. It's a corncob all the way from 11 to 17, and has enough of a low gear to get me over anything I normally come across. Much nicer experience when the majority of my riding is -1% to 1%...

Iride01 

Shimano also tells you that information too. Look for the DM about your rear DR. If your stuff is old enough that there isn't a DM, then it'll be in either the SI or UI.
https://si.shimano.com/#

Sometimes the number of rings on the front makes a difference in their procedure. But all in all, most every procedure winds up within a link of each other. Not a big deal as long as your chain is never too slack or so short it pulls your pulley wheel into the cassette.

Park Tools also will give you the general ways to size your chain also.
https://www.parktool.com/blog/repair...&area%5B%5D=50

msu2001la

You could shorten the chain, but I don't see why you'd need to. The amount of chain being used is no different than it would be in the 30t on the current cassette.

mizer2167

Can you use the derailer that comes with the 11-34 HG800 without modification using the SRAM PG-1170?

I'm in a very flat area and wish for the 14 and 16 I don't have quite often.

SoSmellyAir

The method specified in the Shimano dealer manual assumes that one is using the correctly spec'ed rear derailleur, i.e., SS (short cage) for 30T max rear cog or GS (medium cage) for 34T max rear cog (latest 11 speed generation). Since I am using a GS rear derailleur with a 12-25 cassette, absolute perfection is unattainable. I simply route the chain around the big chain ring and the biggest rear cog and the rear derailleur and break the chain conservatively at a spot so that the chain can make a slight bend around each rear derailleur pulley; I figure it is easier to remove another link or two if the chain ends up slightly too long than to add another link or two if the chain ends up slightly too short. Leaving the chain slightly long also allows me to swap in my other 11-28 cassette.

SoSmellyAir

Have you considered the Shimano 12-25 or the 14-28 (Ultegra Junior) cassettes?

mizer2167

The 12-25 wouldn't work with my rear derailer, at least based on the literature.

I had not considered the 14-28 as it's missing the 13 tooth cog I ride in quite a bit. I have no real use for the 11 as there are so few large hills.

I've been considering doing a mix and match cassette, but the SRAM seems like exactly the gears I need w/o the extra expense or effort...provided it works.

SoSmellyAir

I am not sure what you mean by mix and match, but I have tried to make a Frankenstein cassette from two Ultegra donor cassettes and could not get the down shift at the transition (between the two donor cassettes) working properly.

mizer2167

Taking the front ~half of a Shimano 12-25 and mixing it with the 11-34 or an 11-30 around the 4th or 5th cog. What you refer to as a "Frankenstein".

I've heard it's possible, but also expensive unless you have one of the donor cassettes already.

SoSmellyAir

In practice it should work; there are some who use MTB rear derailleurs to shift road cassettes (of the same number of speeds) for downhill runs. The trade off may be an imperceptible but measurably slower shift.

Got it.

That is probably the best option. The SRAM maintain 1T gaps at the (physically) smaller end of the cassette at the expense of bigger jumps between the (physically) larger climbing cogs, so its suitability depends on how you want to tackle the intermediate climbs on your rides.

jjay03

I am interested to see what all comes out for the new 12 speed stuff. Maybe I should wait before upgrading.

aliasfox

Yes, there really shouldn't be any changes. the PG-1170 is a drop-in replacement for Shimano 11-speed systems.

As for chain length, as long as your minimum number of teeth are the same (11t back, 34t front), you don't need to shorten the chain. And as long as your maximum number of teeth are the same or fewer, you wouldn't need to lengthen the chain either. If a derailleur can handle 34t, it can handle 28t.

You may need to make sure your derailleur is in adjustment though - the HG700/800, as far as I'm aware, has the big cog slightly further inboard (can anybody confirm this?) - one would adjust the limit screw slightly to compensate for any other cassette having their biggest cog a tiny bit further out.

mizer2167

I purchased the 11-28 SRAM, so we'll see how it works out.

biker128pedal

I have a 2021 Domane SL6. I took off the 11-34 and swapped it for and 11-28. The numbers can be confusing. Should have gone 11-26. One thing. The 11-34 has a spacer behind it. You won’t need that for a swap. I did spend the money and stick with Ultegra. Still not used to the compact up front. My first on a road bike.

Did not touch the rear derailleur. May be could have adjusted the b screw. Saving the 11-34 for the mountains. Want a second set of wheels. Next year.

Iride01 

If the cost of 12 speed stuff in the near future isn't outside your budget, then certainly a new 11 speed cassette for your current bike is just a pittance.

You'll have to buy new shifters for 12 speed and those typically are one of the most expensive component of any groupset upgrade.

SoSmellyAir

And it will be a long wait. All the new Shimano 12 speed groupsets will be snapped up by bike manufacturers for their new high end models. And it sounds like (from Shimano) that the number of different 12 speed cassettes will be less than that for 11 speeds, given that the 12 speed cassettes cover broader gear ranges. So even individual cassettes won't be available for a while.

jjay03

I checked yesterday and it appears I mostly use the 15, 17, and 19t sprockets. I may just upgrade my cassette and wheels/tires for now and throw a Stages left crank arm on it for power. I hear the dual sides ones are not very accurate on this Gen.

My only concern with a more compact rear sprocket is would that cause me to cross chain more? If they are only 1T apart now in spacing I would prob use more sprockets across the cassette of course and cross chain. Would have to use my trim position more on the FD thats for sure.

aliasfox

If you never find yourself "between gears" and wanting a 16T or 14T, then you should be fine.

Cross chaining only really matters at the outer-most combos, so if you're not running 50x30 or 34x11 today, then you'll be fine. Otherwise, a slight difference in chain angles isn't going to make a difference with regards to real-world, non-race performance.