Jozko

Hi folks, got a question about upgrading from 10 speed (Tiagra 4700) to 11 speed (105 7000) system.

So I bought my bike few years ago when I was starting out in cycling and have since done bunch of cycling holidays in the mountains.
I'm not strong enough to climb using 11-28 cassette so I always solve it by renting bikes wherever I go. I would however love to take my bike with me this year so I'm toying with the idea of upgrading the groupset to 105 R7000 which would include 11-32 cassette.
As I'm not much of a technical person when it comes to bikes, I'm not even sure it can be done so I'd like to know.

- my biggest concern is whether the frame itself would even allow it? My worry is that frames are specifically made for 10/11 speed systems.
- would I have to change the rear wheel?

I know I could just upgrade to 10 speed 11-32 Tiagra, but I feel like giving my bike a proper upgrade.

It's a Merida Reacto 300 road bike, 2017 model.
Thank you.

skidder

Merida bicycles are not sold in the USA (at least where I live in California) so I'm not sure exactly what yours looks like. Anyway, I'd suggest just getting a similar 10 speed cassette to what you have now, but with a 32 tooth big ring, and see how that works. It should be a simple swap as most Shimano RDs can be used with the larger 32-tooth cassette ring; you might have to buy a new RD, but try just the cassette swap first. Changing to a 11-speed cassette might create problems with indexed shifters, which could cost you more if you have to buy new shifters/brifters and a new RD.

Jozko

Thanks for reply.
In case I do decide to go this way, would I also need a new (longer) chain?

dsaul

Switching to 11 speed will cost more than the bike initially cost. It's just not worth the expense.

If you have the 4700 GS medium cage rear derailleur, it will work with up to a 34t cassette. If you have the SS short cage derailleur, you will need to get the GS derailleur to go with a larger cassette. The GS derailleur is about $40.

02Giant 

I would put a new chain on a new cassette.

If the current derailleur won't clear the new cassette, a Wolftooth Roadlink will fix that.

MoreLowGears

Frame compatibility is the same across 10 and 11-speed groupsets. Your concerns are:

• Wheels: most 11-speed road cassettes require a wider free hub (part of the wheel) than 8-10 speed ones. This is not the case for 11-34 cassettes and larger, which use the same freehub size and the biggest cog hangs over the end of the freehub. I think 11-34 and 11-36 are great sizes for climbing bikes, but the gear ratios at the tall end (small cogs) of the cassette so make sure you’re ok with that.
• Shifters, cassette: these are obviously speed-specific and will need to be replaced. Make sure you buy the appropriate shifters (cable or hydraulic) for your brake type
• Derailleurs: you’re in luck: the 4700 group set is the only 10-speed groupset that has the same cable pull ratios as 11 speed groupsets. You can upgrade in-place to 11 speed without changing these. Make sure you have the long cage (GS) rear derailleur for your wide-range cassettte. Shifting performance of the 4700 group is almost identical and the weight increase is only noticeable on a scale.
• Chain: I recommend buying a new 11speed chain because you should get a new chain whenever you get a new cassette. That said, your old chain will work but have degraded shifting performance.
• Brakes: will work without issue.

My recommendation: just buy the shift levers, chain, and a 11-34 cassette.

Kedosto

Cheapest option is to just swap in a new 10 speed cassette (11-34) and maybe a smaller chainring up front. As stated above, you’ll need the gs version derailleur so if yours isn’t the longer gs you’ll have to spring for one.


-Kedosto

Russ Roth

MoreLowGears has got it; shifter, chain, and cassette are all you need and if you already have to do a chain and cassette the increase for the shifter isn't that bad. Considering doing this with one of my bikes since I found a deal on some 11sp hydraulic brifters with the calipers. Just have to keep your eyes peeled for a deal.

Chris!

My bike came with an tiagra 4700, a 11-34 and a 50 34 crankset. I was not happy with the gearing so I got a FSA 46-30 crankset and I believe last model deore xt 11-36 cassette. I have not intalled the cassette yet but there are YouTube videos of the medium swing tiagra going to a 36. Shimano is usually pretty conservative on there ranges. Hope that helps.

MoreLowGears

Boosting this. I have a mid-cage Sora R3000 rear derailleur running a 12-36 with no issues. The newest 105 and above have even better clearance. I think it’s safe to assume that all Shimano rear derailleurs rated for a 34t sprocket will also clear a 36.