Could I change my bike this much?

bongofish

Used my Boardman adv 8.8 over last few days and kept my btwin 900 ultra in the shed. I have to say even though the Boardman is a heavier bike it currently feels nicer to ride and I think one of the main reasons is its gearing. It has a sub compact chainset if 48/32 and the back is 11-32. Even though the bike is heavier than the btwin hills are kind of enjoyable on it/ easier and seem to get a great top speed on it too down hill.

So I was wondering if it would be possible to fit this kind of gear ration on my btwin road bike? It's currently 11-28 and the standard 105 groupset in everything.

Would love this same gearing set up on the btwin but no idea where I would need to start or what kind of price outlay it would be and what I would specifically need.

Any help would be great. Thanks all!

whyamihere

105 R7000 (the newest version) supports an 11-34 cassette with the medium cage derailleur. If you then get a compact (50-34) chainset, that will give you the 1:1 bottom gear which is the same as the Boardman. If you just changed the cassette, chain and rear derailleur, that would give you a 36-34 lowest gear (a ratio of 1.06:1) which is very nearly as low already.

joe_totale-2

Before you change the chainrings make sure you check to see if the front derailleur will move down that far.

Cheeseface22

Devil's advocate: why would you want to clone your Boardman on B'Twin to get two bikes that would feel the same? Might as well have one bike?

I have no idea on the price, quality, etc. of those two bikes, but this is how I think:

I'd treat your Boardman as a "faster" or "better" bike for those sunny day rides (or when you're feeling a bit tired, sluggish and not motivated to cycle) for a boost, if it gives you more enjoyable ride and faster perception.

And I'd treat your B'Twin as a "challenge" or even a "winter" bike to get you working through the gear ranges and push you a bit. You know those days when you're up for a challenge or some hard training. Then, when you hop on to your Boardman, you'd feel the difference and you enjoy riding again.

Just a thought. Or simply ride whatever you feel like and change it up a bit time to time. No hard science about it, as long as you're enjoying cycling.

N0bodyOfTheGoat

To get everything you need from one place, it will be hard to beat...
https://www.merlincycles.com/shimano-10 ... 17086.html (£37)
https://www.merlincycles.com/shimano-10 ... 17065.html (medium cage £45)
https://www.merlincycles.com/kmc-x11-el ... 57840.html (£25)
£107, but sign up if you aren't already, use reward points to get £10 off a £100+ basket... £97

Or by the rear mech for £37 in black from https://www.chainreactioncycles.com/shi ... prod173487 as well as the final 11-34 cassette in stock for £35 https://www.chainreactioncycles.com/shi ... prod173328 , no decent deals on KMC chains in stock but if you get your basket over £150 you can then get a whopping £10 off using a British Cycling membership discount code (it was 10% off a £99+ once per month until around last August).

cougie

What if it's not the gears though ? It's a completely different bike.

N0bodyOfTheGoat

Iirc I warned the BTwin was a nice spec for the price, but the 36/52 chain set with an 11-28 cassette may be a challenge on the hills for someone starting out.

Heck, two years on from when I started my mission to get fitter, I still wouldn't want that gearing for tackling the likes of the top of Harvesting Lane or Turkey Island etc. on my South Downs hilly rides.

I've not fitted them yet, but I've got that rear mech and 11-34 cassette ready to replace my 11-32, to give me more climbing gears and an easier "emergency gear" if I need it to climb the ~20% section of Bwlch Y Groes... Hopefully this year!

bongofish

NitrousOxide wrote:

Iirc I warned the BTwin was a nice spec for the price, but the 36/52 chain set with an 11-28 cassette may be a challenge on the hills for someone starting out.

Heck, two years on from when I started my mission to get fitter, I still wouldn't want that gearing for tackling the likes of the top of Harvesting Lane or Turkey Island etc. on my South Downs hilly rides.

I've not fitted them yet, but I've got that rear mech and 11-34 cassette ready to replace my 11-32, to give me more climbing gears and an easier "emergency gear" if I need it to climb the ~20% section of Bwlch Y Groes... Hopefully this year!

Yes I believe you did warn me haha.

Wayne Plunger

Should have bought a Calibre!

Alejandrosdog

I blame Merlin

super_davo

If I were the OP I would first get an 11-32 cassette (which is still a big change from 11-28).

You may be able to run it with no alterations, check the chain on big - big and see how it looks. If too short, buy a new chain. If the mech doesn't clear, buy the R7000 mech.

You'll definitely be OK if you have new chain, cassette & mech, but depending on how long the chain is cut and your bike you may be able to just get a c£30 cassette.

This of course assumes a level of mechanical competence - if that's lacking take to a shop and get all 3!

MiddleRinger

I wouldn't go changing the front rings just yet. Do the cassette first.

Assuming your current rear mech will handle the larger sprocket, it's a pretty straightforward job to change the cassette. To do it yourself you'll need the following and about half an hour of spare time:

- The new 11-32T cassette (obvs)
- New chain (maybe, your current one MAY be long enough)
- Chain whip
- Cassette lock ring tool
- Socket set or wrench to fit onto the lock ring tool
- Grease
- Allen keys (to adjust rear mech if it needs it)

It seems like a bit, but they're all handy tools to have anyway for future maintenance! :-)

zerolight

I'd be changing out the chainrings and cassette, and therefore the derailleur and chain. No way I could cope with that gearing. I struggled with 50/34 and 11-28. The 11-32 made a world of a difference to me. We aren't all race ready athletes.