Gearing Change - Advice please??

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theredsnapper
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Joined: 21 Feb 2014, 5:06pm

Gearing Change - Advice please??

Post by theredsnapper »

Hi,

I've been trawling through the archives and also the old CTC site, great resource by the way, but I've not really found the answer, simple answer, if there is one about the 'best', most practical way should I say, to reduce the gearing on my newly acquired, 'old' road bike.

It's quite a nice JF Wilson 653 race geometry affair, and is geared as such, 9 speed, Shimano 105 Brifters, 105 Fr Mech and a Short Cage 600 rear mech, 52/42 with a 12/25 cassette, currently giving me, according to Sheldon a best gear of 44" up to 105".

So, not being as fit as I used to be, and getting back into road cycling from MTB, I've been spoiled by the granny ring, and it's not too flat where I live on the edge of the Peak District, could anybody advise me on the best way to move forward, obtaining some more usable gear ratios until I can keep losing weight and become fitter?

I'm thinking changing the cassette and rear derailleur might be the cheapest way, the bottom bracket being a square taper affair and possibly costing more!

Hope I'm not being a pain, but riding flat routes is getting a touch boring, suggestions with actual equipment to source would be gratefully received, I do bow down to the knowledge on here, and I'm sure your experiences will be worth their weight in gold to me....cheers in advance!

Red
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Vantage
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Re: Gearing Change - Advice please??

Post by Vantage »

£50 gets you a 46/36 toothed chainset, quite a nice looking one too imo.
http://www.spacycles.co.uk/products.php ... 2b0s109p45

The 12-27 would also give you a couple less inches to push without changing the rear mech or a longer MTB mech could get you using an 11-34 jobby which would get you up almost anything.
http://www.spacycles.co.uk/products.php ... b0s150p556
Bill


“Ride as much or as little, or as long or as short as you feel. But ride.” ~ Eddy Merckx
It's a rich man whos children run to him when his pockets are empty.
theredsnapper
Posts: 93
Joined: 21 Feb 2014, 5:06pm

Re: Gearing Change - Advice please??

Post by theredsnapper »

IrishBill76 wrote:£50 gets you a 46/36 toothed chainset, quite a nice looking one too imo.
http://www.spacycles.co.uk/products.php ... 2b0s109p45

The 12-27 would also give you a couple less inches to push without changing the rear mech or a longer MTB mech could get you using an 11-34 jobby which would get you up almost anything.
http://www.spacycles.co.uk/products.php ... b0s150p556


Hi Bill,

Cheers for that, and yes, Stronglight is a name I know, and looks right too, providing 35" and 6" increase in lowest gear...if I opted for this would I need to change the front mech as well? Also if that is the case, would it be worth going down to a 48/34, providing a 33" with the 27 cog, keeping the upper end but getting those lower inches? Would the front mech change be one for a triple or compact designation?

Also, which MTB changer might you recommend?

Red
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Vantage
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Re: Gearing Change - Advice please??

Post by Vantage »

To be honest with you I couldn't say with regards to the front mech. From past experience when fitting a bigger or smaller chainset, I've just moved the mech up or down to compensate for the difference. But I believe certain mechs are limited in the range of teeth they'll cover. If you know the exact model number or year of the mech I'm sure someone here will have that info to hand or be able to find it for you........Brucey springs to mind......I doubt there's anything relating to bikes that he doesn't know. I'd guess that a 34 to 48 tooth jump might well be too much for any mech to handle and unless theres plenty of gears inbetween on the rear cassette, your legs will feel the jump too.
As for the rear mech, I've never run more than an 8 speed set up on any bike so not much use to you there. I will say that I've been using the stock Acera mech which is very much bottom end Shimano and tbh, over the last 2 years and 6,333 miles in sun, rain and everything in between, it's been perfect. The Alivio is 9 speed compatible and better quality so I would guess do just as good a job. Depends on how posh you want to go I guess :)
Good luck :)
Bill


“Ride as much or as little, or as long or as short as you feel. But ride.” ~ Eddy Merckx
It's a rich man whos children run to him when his pockets are empty.
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Sum
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Re: Gearing Change - Advice please??

Post by Sum »

The Short Cage 600 rear mech has a total tooth capacity of 28T I think (I may be wrong on this). If that's correct then as your 52/42 chainrings use up 10T of this, leaving 18T for the cassette, you may be able to use a 12-30T Tiagra or Ultegra cassette which will reduce your lowest gear to 37" without having to change anything else. If you need a lower gear then you will need to change the chainring (or fit smaller wheels!)

Just to check: The 44" up to 105" in the OP represents a gear range of 239%. However 52/42 with a 12/25 cassette represents a gear range of 258%. Is the OP correct, or is the current cassette a 13/25 perhaps?
theredsnapper
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Re: Gearing Change - Advice please??

Post by theredsnapper »

Sum wrote:The Short Cage 600 rear mech has a total tooth capacity of 28T I think (I may be wrong on this). If that's correct then as your 52/42 chainrings use up 10T of this, leaving 18T for the cassette, you may be able to use a 12-30T Tiagra or Ultegra cassette which will reduce your lowest gear to 37" without having to change anything else. If you need a lower gear then you will need to change the chainring (or fit smaller wheels!)

Just to check: The 44" up to 105" in the OP represents a gear range of 239%. However 52/42 with a 12/25 cassette represents a gear range of 258%. Is the OP correct, or is the current cassette a 13/25 perhaps?


Thanks for that Sum! That could be a great start, as for my rear cog I'll check later, my wheels are just ready to collect following a rear wheel rebuild and front bearing change, so I can't count..:)

Red
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Sum
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Re: Gearing Change - Advice please??

Post by Sum »

D'oh! Neither can I count as well: I've just realised the 12-30t cassette is 10 spd, not 9 spd. There is a 11-30T 9 spd Tiagra cassette which will stretch your mech capacity a little. Alternatively you may be able to swap the 12 and 13T of your existing cassette with the 11 and 12T of the Tiagra cassette to make a custom 12-30T cassette.

I should add that the modern road short cage mechs are not supposed to be used with sprockets greater than 27 or 28T but sometimes you can push this a little.

EDIT: I've made the link to the 11-30T 9 spd Tiagra cassette, available at CRC, more prominent.
Last edited by Sum on 18 Apr 2014, 5:55pm, edited 1 time in total.
bealer
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Re: Gearing Change - Advice please??

Post by bealer »

Pick up an old school 9 (or even 8 I believe) Shimano XT rear mech mid or ideally long cage from eBay or alike. I've picked up some for about £20 recently.

Then put an 11-32T cassette on the back. I prefer 11-30T but it might be harder to find in 9-speed.

That'll ease things initially. Then changing your chainset would be next. I'm not very knowledgeable about doubles, but a triple Stronglight chainset would allow you an inner ring of 24T or 26T.
theredsnapper
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Joined: 21 Feb 2014, 5:06pm

Re: Gearing Change - Advice please??

Post by theredsnapper »

Hi folks,

Thanks for the responses, I've plenty to go on now, I'll try and work up some of the options!

Cheers,

Red
JohnW
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Re: Gearing Change - Advice please??

Post by JohnW »

Right snapper - I'll tell you what I'd do - but be aware that I'm probably a lot older than you and have less need for higher gears.

Firstly I'd be checking on the 600 short-cage - be sure that the upper jockey wheel gets low enough for a big dinner-plate sprocket. 600 short-cage rear mechs in the days when I was buying short-cage rear mechs wouldn't reach beyond a 28T big sprocket............but I don't think you need to change your block/cassette anyway.

Second, I'd check that the cable to the rear changer went underneath the bottom bracket. If it runs on top of the bottom bracket, and therefore on top of the chainstay, that could foul the front changer cage and prohibit very small chainrings.

Third - I'd ensure that I was using down-tube friction gear levers and not STIs, because the latter would have compatibility problems and possibly precipitate expenditure into the range of megabucks.

For a while, on one of my bikes I ran chainrings of 32-44. This used a 22-44 triple, with the super-gran ring taken off, and a shorter bottom bracket spindle. I was using a 14-28T freewheel block and gave me 31" - 85" gear range. That was all I needed for clubriding and solo day rides of 120 miles+. I could pedal up to about 25mph, and freewheel the rest.

If all is well, with respect to the points above, I'd do again what I did, and ride with 22-44T rings on the existing 12-25T block. That'll give you 23" - 99" gear range, and surely that'll be enough for a young whippersnapper like yourself.

I'm not telling you what to do - it's just what I'd do myself particularly if costs were of the essence. You'll get one of Spa's 44-32-22 triples for £35.
theredsnapper
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Joined: 21 Feb 2014, 5:06pm

Re: Gearing Change - Advice please??

Post by theredsnapper »

Hi John,

Thanks for those options, I currently have STI's on the bike, but I'm sure the chainring options you suggest are worth exploring, don't be apologising, it's all things to consider..:)

Red
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