Help I need smaller gears - what can I do? A GUIDE

jibberjim

Ouija wrote:

Since your using mountain bike cranks with a wider axle, you'd obviously need to use a few more spacers on the non drive side and probably a single spacer on the drive side to get it all to work. Remember that a lot of mountain bikes also come with 68mm bottom bracket shells, hence the reason they include spacers with mountain bike HT2 sets. You'd just need to use less than the recommended 2 spacers drive side, 1 spacer other side of most mountain bikes (in this case, 1 spacer drive side, 2 spacers other side).

Also worth having a few 1mm and 0.5mm spacers to play with instead of the obligatory 1.5mm spacers most HT2 cranks come with.

Aha - of course, I hadn't thought about just putting the spacers on the NDS... I'm kinda dumb to have not considered it. Thanks! I guess I may well try it...

barrie h

LittlePlums wrote:

I currently have a Campag Veloce compact(50/34) with a 12-25 cassette. I find myself running out of gears on the longer and steeper hills in the area and find some of the gears are quite "samey". This may be because I am used to mountain bike gearing.

I would like to increase the range of gears and one option would be to go for a 13-29, but I'm a bit reluctant to lose the top end on my current set-up (12). What I want to know, therefore is, if it is possible to mix and match 2 cassettes to end up with, effectively a 12-29? I understand that Campagnolo have individual sprockets, so in my mind this should be possible, but I don't know if there are any limitations and appreciate that there would be bigger jumps in perhaps the middle gears.

You help would be much appreciated.

My penny`s worth,
Campag 10speed 13/29 with the 13 changed to a 12 at the front 50/40/28

Last week I went up Fleet Moss , Yorkshire.( the top bit is 20% )

and by the way I`m 66

Barrie

chrisw333

Hi
I have a shimano 105 RD5600 rear derailleur short / standard cage. Current cassette is 12-25. (Compact 34/50 up front)

I'd like slightly easier gears and realise this derailleur was only specified to go up to 12-27.

However, I was wondering if it would cope ok with a 12-28 cassette? Has anyone else has success with this specific model.

Thanks

chrisw333

Well, if anyone else is interested I gave it a go and seems to be working ok

SpokeyDokeyBlog

You can fit a mountain bike cassette to a 10 speed road bike (Shimano), by using a 9 speed Shimano mtb rear mech. A 10 speed mtb mech has a different cable pull, but for some reason, the 9 speed mtb cable pull is exactly the same as 10 speed road.
Lots of cross riders do this to get smaller gears, but stay away from the 10 speed mtb rear mech on a 10 speed road system, it won't work.

Paulisabout

Hi,

New to road biking and got a good deal on EBay for a Trek 15c.

I went out last week in the Mendips and struggled on any hills.

The front has a 39/53 and the back a 12/25 with a 18cm crank length.

From what I have been reading this might be a bit tough for a beginner - any thoughts.

Cheers, Paul in the Mendips.

hughgabriel

Paul,
180mm cranks are huge (assuming you're measuring centre of the bottom bracket to centre of pedal spindle) so unless you are 6'4"+ and very strong (do you have a MTB background?) that would be a good place to start.

A standard double (39/53) and 12-25 is only moderately hill friendly so maybe try and get some compact chainrings for the time being, or a 12-28 cassette.

Hope that helps
Hugh

ps. I've recently gone hill hunting and have just given on an std double and 12-23, not running 38/53 and 12-27 (SRAM cassette).

secretsam

Quick Campagnolo question: I have a 13-29 cassette ready to go on my (Veloce) bike, currently running 12-25, will I need to lengthen my chain??? (Please say "no" as I don't have any spare links!)

Initialised

SecretSam wrote:

Quick Campagnolo question: I have a 13-29 cassette ready to go on my (Veloce) bike, currently running 12-25, will I need to lengthen my chain??? (Please say "no" as I don't have any spare links!)

Yeah, you probably will unless you're a good boy and wont forget not to cross-chain. Four extra teeth means four extra links. You'll get away with it if:

Put your bike in the big ring and the largest sprocket, can you fold the chain to allow an extra four links?

If yes: congrats you've been running your chain too long all this time, go for it.

If no: you're going to need a bigger chain or be very careful about cross-chaining.

drlodge

SecretSam wrote:

Quick Campagnolo question: I have a 13-29 cassette ready to go on my (Veloce) bike, currently running 12-25, will I need to lengthen my chain??? (Please say "no" as I don't have any spare links!)

I would guess its already the right length. Check out your chain on small-small and big-big, this will tell you. On short-short you should have minimal take up by the RD i.e. the chain is as long as it can be. This being the case, you should be fine with the new cassette. But if the chain hasn't been setup to be "as long as possible", then your RD will already be stretched on big-big and hence you'll need a new chain.

I just changed my 12-27 to 12-29 and put on a new chain...not surprisingly the length of the chain was the same as the old one, since the chain had been setup to be as long as possible, and the small-small is the same.

amycollins

upgrade your rear casette, i bought my bike and it had a 11/25 casette on it.. which is tiny! now ive upgraded to 12/30 and i fly up hills

delbi1

i have just brought a carrera tdf (not great but best for my budget) and it has a 14-28 7 speed cassette on back, people say these are hard up the hills but that aint a problem i am having. i want more speed on the flat/downhills, can i put Shimano Acera HG41 7 speed 11-28 to achieve this with little fuss?

Ouija

Depends if it's a freewheel or freehub. 7 speed was about the time when they switched from one to the other so nearly everything below 7 speed is freewheel and everything above is freehub but 7's can be either. The Acera HG41 is for a freehub. Typically freehubs are capable of taking 11 teeth cassettes and freewheels don't take cassettes at all and tend to start with with a much larger small ring (hence the reason i ask, since you say it's 7 speed and a 14t small ring).

delbi1

how can i tell if its freewheel or freehub ?
reading around the web i can`t find any answers

ah nm i found the answer on another forum
Shimano HG30 or 40 would be fine speed "cassette" with an 11-28 range stock freewheel is 14-28

mugensi

chrisw333 wrote:

Hi
I have a shimano 105 RD5600 rear derailleur short / standard cage. Current cassette is 12-25. (Compact 34/50 up front)

I'd like slightly easier gears and realise this derailleur was only specified to go up to 12-27.

However, I was wondering if it would cope ok with a 12-28 cassette? Has anyone else has success with this specific model.

Thanks

I swapped my 12/25 on my 105 equipped bike to an Ultegra 12/28, it works perfectly. I had to make minor adjustments with the indexing afterwards but it works 100%.

dav1d1

i am currently running and campy centaur 50/34 and 12-25 rear, and find on hills i struggle, but i wonder why as i do a lot of gym strength work, squats etc, on the flat i can output high power for a long period of time, than soon as i get to a long hill i just get dropped, so am thinking of changing to a 12-28, would i need to length the chain also?

surrey_commuter

Dav1d1 wrote:

i am currently running and campy centaur 50/34 and 12-25 rear, and find on hills i struggle, but i wonder why as i do a lot of gym strength work, squats etc, on the flat i can output high power for a long period of time, than soon as i get to a long hill i just get dropped, so am thinking of changing to a 12-28, would i need to length the chain also?

how many miles do you have in it - might be best to change both. why not go bigger to 30 or 32T it was the best decision I ever made

ademort

I,m going to climb the Alp du'hez six times for charity in June 2015. I currently have a Shimano Ultegra 10 speed set up with smallest gear combo of 39x25. Other members have suggested smaller gears. What would be the best way to achieve this. I would much prefer to increase the rear sprocket size as this would be the easiest solution but how big a sprocket could i fit. What is the maximum. I could also put a 34 inner ring on the crankset but this means removing the crankset and BB and i don,t really want to go down that road for just one event. Any advice welcome.

Ouija

According to Shimanos docs, depending on which derailleur you've got (GS/SS) you can go:

GS
Maximum Sprocket 32T/12T
Minimum Sprocket 28T/11T
Maximum Front Difference 22T

SS
Maximum Sprocket 28T/12T
Minimum Sprocket 23T/11T
Maximum Front Difference 16T

So the GS gives the wider range or 22 teeth difference between small and large sprocket but even the SS will get you a 28T big ring as long as you make sure the smallest ring is 12 teeth and not 11 (16 teeth range).

ademort

Thanks for the reply. I have the SS version so 28 is the largest rear sprocket i can fit. I,m more worried about the chainset i have the standard 10 speed Ultegra 53x39 and it,s been suggested that this needs to replaced by a compact 50x34 so it,s going to cost a few quid plus the fact that my Mavic carbone SL wheels will also need to be replaced for the event as they are not suitable for climbing i,m thinking seriously about hiring a bike for the event will probably be cheaper all round.

Ouija

If it's a hollowtech II crankset then changing out the rings is as simple as it get. All you do is loosen the bolts on the NDS crank, unscrew the plastic pretension endcap with one of these and slide the whole drive side out and change the rings (also with an allen key or with with one of those star shaped thingies you also use on disc rotor bolts). And then slide it back through the bottom bracket, tension it up with the plastic end cap and tighten the pinch bolts with a allen key. It really is idiot proof and there's no need to touch the bottom bracket itself. The only thing that can go wron is if you add too much preload to the bearings with the plastic endcap but you'll know if you done this as the cranks will be stiff to turn.

Manc33

I have 24/36/48 at the front and 11-32T at the back.

I wouldn't push it any more. Chain catcher is a must on this setup.

All that seemed to matter to me was getting that front mech cage insanely close to the outer chainring.

Now my chain is falling off the granny ring (since swapping to another brand of cassette) I think the FD needs moving up 1mm or something, will that alleviate it dropping off the granny ring? The physics/mechanics of it in my mind suggest so since the angle will be altered.

I have heard of a 24/36/50 setup but I'm not risking it. 48x11 is enough on a flat bar bike and 24x32 is nearly mountain bike gearing. On a MTB you'd only (typically) have a 44x11. Its all about the chainring sizes. I don't think even the top MTB groups had anything more than a 46T on them.

You probably need a decent FD to cope with all of this, I mean slapping a FD-A050 on or whatever ain't gonna cut it.

Ouija

Manc33 wrote:

Now my chain is falling off the granny ring (since swapping to another brand of cassette) I think the FD needs moving up 1mm or something, will that alleviate it dropping off the granny ring? The physics/mechanics of it in my mind suggest so since the angle will be altered.

Nope. You just need to set the limiter screw to stop the FD moving too far inwards when dropping into the granny ring. All shifters let the cable go completely loose on the granny ring and leave it up to the limit screw to determine the correct distance to move inwards towards your frame. Too much and it'll throw the chain off the ring.

Under no circumstance move the derailleur out by increasing cable tension. This just means it won't sit right in the middle ring and probably try and throw it off the big ring (setting the outer limiter screw to prevent the latter will, in most cases, simply make it ridiculously difficult to get onto the big ring due to higher cable tension)

And FD's don't need moving or recalibrating when you change cassettes. Not if they were setup correctly in the first place. I switch out wheelsets on my main commuter with a variety of wheels which have Shimano and SRAM units. Some only 11-28, some 11-34, some with pyramid shaped cassettes (shimanos) and some with all the low gears bunched up towards the wheel side (SRAM). There's no need to adjust anything other than minor indexing of the rear mech.

Manc33

I turned the inner limit in slightly and put my old chain catcher on.

Changes gear so well (new Shimano cassette, replaced with SRAM) I started thinking about a bigger middle ring lol, in other words the better gear changes were ultimately making me able to speed up better. I'd like to say "You get what you pay for" but the Shimano cassette was cheaper. Its about 10% heavier which is why I never got one but I prefer it already after only doing 5 miles on it.

With a 24T granny and 32T low sprocket it looks insane with 700c wheels. I might even get a 50T to experiment. :twisted:

This thread is about smaller gears but its the gear range that matters to me. Once that front tooth difference gets to 26T... its no man's land. I heard a rumour about an Ultegra 6603 working on that kinda setup but who knows, or that Campag mech definitely does but I can't remember the name of it.

rolf_f

Manc33 wrote:

48x11 is enough on a flat bar bike

48-11 is enough on a flat bar bike?!! Given you can't get up gentle hills without an enormous cassette and tiny chainring I would suspect that 48-11 is way more than you need on any bike. I've got 48-11 on my touring bike. The 11 is needed because there isn't really enough clearance for the smallest sprocket at that size - a 12 would probably jam the chain between sprocket and frame. The 48 is there because it dates from when the bike originally had a 13 tooth smallest sprocket. But 48-11 is actually a bigger gear than my fast carbon road bike has at the moment (50-12). What you should be thinking about doing (if anything - I mean really, just leave things alone!) is getting a smaller big ring - eg a 44. Then you could run 44-34-24 which would be pretty nice.

apprent1ce

On my secondhand Supersix I've currently got: 34/50 and Shimano Ultegra 12-25.
Currently, downhill around the low 30mph I find I'm struggling to keep up with the pedals and I wondered if the 11 tooth small cog will make that much difference?

On wiggle in the clearance sale there is a Shimano Ultegra 6700 10 Speed 11-28 cassette however from reading this thread this appears to be outside the 16 tooth difference recommended by Shimano. Would this be okay and would it make much difference descending/climbing?

Thanks, another newbie that finds this site invaluable!

Manc33

apprent1ce wrote:

On my secondhand Supersix I've currently got: 34/50 and Shimano Ultegra 12-25.
Currently, downhill around the low 30mph I find I'm struggling to keep up with the pedals and I wondered if the 11 tooth small cog will make that much difference?

It is a 8% higher gear at the top end, it is a decent jump up.

I am on flat bars, but still use the 52x11 sometimes downhill.

apprent1ce wrote:

On wiggle in the clearance sale there is a Shimano Ultegra 6700 10 Speed 11-28 cassette however from reading this thread this appears to be outside the 16 tooth difference recommended by Shimano. Would this be okay and would it make much difference descending/climbing?

Thanks, another newbie that finds this site invaluable!

Are you sure that 16 tooth difference isn't talking about the front chainrings tooth difference?

If it does mean the cassette, its probably out of the range of a short cage rear mech and you'd need a GS. I think on a short cage rear mech a 26t low sprocket is about the safe limit.

gmacz

Best thread on the site, loads of great info, time to fire it up again.
Triple 30-42-52 and 12-26
Compact 34-50 and 12-30
I have calculated that the new compact has a lower climbing gear but loses out on the high gear.
Easier climbing but lower top speed.
Is this correct?
1.2 and 4.3 against 1.1 and 4.2
Will I notice any difference with these ratios.

dj58

Is this the difference in the gearing on your Aluxx Defy and your new TCR?

gmacz

Yes triple alu defy 2011 v 2015 carbon tcr.