Current Projects chat and miscellany

Thanks - I've grown quite attached to the juxtaposition of rusty steel and polished aluminium....

My current setup is:

9 speed Tiagra STIs
Tiagra rear mech (not sure on the exact model, I don't think it's a long cage)
Tiagra front mech (double)
48t & 34t chainrings
12-27 cassette

I have the possibility of some riding with proper climbs in the not too distant future and after blowing out my knee last summer want to increase my range without fitting a triple and having to change my shifters. I figure a 34-32 ratio would make climbing a fair bit easier than 34-27.

What (apart from the cassette) would I need to change to fit an 11-32 or even 11-34 cassette? Thanks.

Fit any 9-speed Shimano MTB rear dérailleur; job done.

e.g. http://www.bike-discount.de/shop/a14755/deore-rear-derailleur-rd-m591-l-sgs.html?lg=en&cr=GBP

If you want to keep your existing rear mech you'll need to check its capacity.
(The ability of the derailleur arm to take up slack in the chain) - assume for sake of argument 30T
you then take your chainset range in this case 14T, subtract that from your capacity and you've got a rear cassette range of 16T e.g. 12-28
if you want a top end of 32, that'll mean a cassette of range 16-32 (which you'll be unlikely to find off-the-shelf.
Alternatively you can make a mental note never to go into the big sprockets when in the big ring!!! - but that's rather risky

My newish Deore works fine with a 14-34.

^^His road RD isn't going to shift onto a 34t sprocket anyway. Total capacity of a long cage road dérailleur would be sufficient, but nominal maximum sprocket even on the long cage ones is 27t, which you can usually push to about 30t.

^ fair point

I'd consider the price difference between replacing the rear mech and cassette, or simply going to an 11-27 (increase of roughly 10% ratio when going from 12t to 11t) and then dropping your tooth count up front.

My current setup is:

9 speed Tiagra STIs
Tiagra rear mech (not sure on the exact model, I don't think it's a long cage)
Tiagra front mech (double)
48t & 34t chainrings
12-27 cassette

I have the possibility of some riding with proper climbs in the not too distant future and after blowing out my knee last summer want to increase my range without fitting a triple and having to change my shifters. I figure a 34-32 ratio would make climbing a fair bit easier than 34-27.

What (apart from the cassette) would I need to change to fit an 11-32 or even 11-34 cassette? Thanks.

Fit any 9-speed Shimano MTB rear dérailleur; job done.

e.g. http://www.bike-discount.de/shop/a14755/deore-rear-derailleur-rd-m591-l-sgs.html?lg=en&cr=GBP

Ooooh this is interesting. I currently have a similar setup, old 105sc 8 speed STIs, with 38, 48 rings and 12-26 cassette. I'm wanting to go on a trip to the lake district, sort of light touring, including some giant monsters of hills (for my puny legs). Does the same answer apply to me, any new Shimano MTB 8 speed derailleur and cassette? Or would the cable pull ratio on the 18 year old STIs not match a new derailleur?

I'd consider the price difference between replacing the rear mech and cassette, or simply going to an 11-27 (increase of roughly 10% ratio when going from 12t to 11t) and then dropping your tooth count up front.

Have you seen the price of chainsets? You're suggesting new cranks and rings and a new cassette, when for under £50 inc. p&p he could get a Deore RD and HG50 11-34 cassette

New cranks on my slave

Or would I be better off just getting a compact crankset?

-Or even just HTFUing?

Sheldon says my current lowest gear (38x26 on 700x28c) is 39.21 inches, if I went down to 38x34 I could get to 29.9 inches. If I were to get a compact crankset with 34t ring and keep my current cassette it would be 34x26 = 35 inches, with a new cassette and derailleur that could be anything down to 34x34 = 26.8 inches.

It seems changing cassette and derailleur is a better idea than changing crankset, then, providing cable pull would be ok?

EDIT, or am I just being weak, and will 39 inches be enough up Hardknott Pass?

Does the same answer apply to me, any new Shimano MTB 8 speed derailleur and cassette?

Yes, in fact you can use a 9-speed dérailleur, so you won't be stuck with cheap stuff. If you have no budget, though, you could take my Alivio off my hands, it's only supposed to cope with a 30t sprocket but I used it with no problems with a 32.

Have you seen the price of chainsets? You're suggesting new cranks and rings and a new cassette, when for under £50 inc. p&p he could get a Deore RD and HG50 11-34 cassette

Just the chainrings, which I've no idea about how much they cost as I don't tend to buy much new/modern parts.

Ah, it seems I may have missed the limitations on chainring size for a given chainset.

will 39 inches be enough up Hardknott Pass?

I remember the classic instructions from the organiser of the Circuit of the Cotswolds - "some of the climbs are pretty steep, so you'll be needing 39/23"; anybody taking that advice without realising who the source was ended up walking. In other words, you can only give yourself gearing advice.

Haha well that could well be me! To be honest, a bit of walking wouldn't be the end of the world, but if I can get more appropriate gearing for cheap then I may as well. I notice I can get the Alivio M410 for £20 new, and it says here that it can do 34t, so I may go for that. I figure that if I'm going to change my setup I may as well go all the way to 34 rather than just 32. Did they make the capacity bigger between your Alivio MC20 and the new M410, or is my info wrong?

Yes, they increased the capacity, MC20 is a 'touring' mech, M410 is a proper MTB mech

Fit any 9-speed Shimano MTB rear dérailleur; job done.

e.g. http://www.bike-discount.de/shop/a14755/deore-rear-derailleur-rd-m591-l-sgs.html?lg=en&cr=GBP

thank you sir.

New cranks on my slave

fit

I remember the classic instructions from the organiser of the Circuit of the Cotswolds - "some of the climbs are pretty steep, so you'll be needing 39/23"; anybody taking that advice without realising who the source was ended up walking. In other words, you can only give yourself gearing advice.

Why does he operate the brake on his hillclimb bike with a gear cable? Is that a very drastic WW solution?

I'd reckon so. Same reason the right lever and bartape aren't present. Every gram, and all that.

Why does he operate the brake on his hillclimb bike with a gear cable?

I doubt that he operates it at all, on the kind of climb that bike was designed for you basically stop dead and topple into the hedge as soon as you stop pressing on the pedals.

although it is a common WW solution for the rear brake cable because of the smaller diameter cable and if it snaps you've still got the front ..

Are the cable outers different weights too? Brake cables have wire running the length, or something?