Road bike gearing.....
 

Subscribe now and choose from over 30 free gifts worth up to £49 - Plus get £25 to spend in our shop

[Closed] Road bike gearing...

49 Posts
28 Users
0 Reactions
195 Views
 mboy
Posts: 12582
Free Member
Topic starter
 

Following on from my last "what am I doing wrong" thread, where seemingly I'm not quite as slow as I thought I was, or I am and there's just loads of other slow people on here too, I have a question about gearing...

My bike has a Tiagra setup with 34/50 compact, and a 12-25 9spd cassette, as from the factory, which I understand is pretty much the norm these days at the price point. Given this gearing is lower than the STD chainsets on more expsnive bikes, with 39/53 setups and 11-25 cassettes seemingly, why do I still struggle to find the "right" gear? I'm either too far down the cassette in the 34T ring all the time, or too high up it in the 50T.

I'm not the fastest or the fittest (you don't say!) rider, but on a mountain bike I can hold my own well. In fact, I run a 1x10 setup on my hardtail and don't struggle with that anywhere (except occasionally wanting taller gears on long descents), but it seems to me I need lower gears still on my road bike... What's the reasoning behind the 34/50 compact then? Cos it's an annoyingly big gap, seems like a 46T outer would make a lot more sense with only a tiny drop in top speed...


 
Posted : 08/05/2012 10:22 pm
Posts: 0
Free Member
 

If you want a 46 tooth outer, Ive got a lightly used one you can have for £10.


 
Posted : 08/05/2012 10:25 pm
Posts: 41395
Free Member
 

Yup, compacts are not for every.one. Even 39-52 is too big a gap for me


 
Posted : 08/05/2012 10:30 pm
Posts: 0
Free Member
 

Train more and get your legs used to turning over the 50 tooth. You really shouldnt need to be using the 34 that much at all unless its really steep where you live? The gap between rings is a bit annoying, but if you get used to riding in the big(ish) ring all the time you'll not need to change down at the front so often....


 
Posted : 08/05/2012 10:30 pm
Posts: 41395
Free Member
 

Uh...what about his cadence?


 
Posted : 08/05/2012 10:33 pm
Posts: 0
Free Member
 

Uh...what about his cadence?

What about it? Very high or low? Spinning is good, but its really not the be all and end all. And is it really that bad to use the small end of the cassette and small ring?

Putting a 46 on would give you CX type gearing? Go for it if you want, but I wouldnt bother, you'll miss the top end if you start riding chain gangs.


 
Posted : 08/05/2012 10:36 pm
 mboy
Posts: 12582
Free Member
Topic starter
 

dt, some details/pics please if you would, might be interested in that.

You really shouldnt need to be using the 34 that much at all unless its really steep where you live?

I don't really use the inner unless I'm climbing, but as a result, I find I spend too much time in the 2nd/3rd cogs on the cassette whilst on the 50T, more so than I'd like. Obviously if I then drop to the 34T to compensate, I'm straight down to about 6th cog on the back to compensate for the massive jump between gears on the front. I've only really found one hill that I couldn't quite manage on the 34-25 bottom gear, but it was steeper than 1 in 4 at the top so hardly surprising really, and I almost made it, but the gap between rings makes for a right faff I find.


 
Posted : 08/05/2012 10:37 pm
Posts: 0
Free Member
 

How long have you had the bike btw? I did find the jump on the compact annoying at first, but now I find I shift down/up almost at the same time and it doesnt annoy me at all now, but everyone is differnt.


 
Posted : 08/05/2012 10:39 pm
Posts: 0
Free Member
 

I've only really found one hill that I couldn't quite manage on the 34-25 bottom gear, but it was steeper than 1 in 4 at the top so hardly surprising really, and I almost made it, but the gap between rings makes for a right faff I find.

Yup, thats steep. No shame in struggling up/ not making it when its that steep!


 
Posted : 08/05/2012 10:40 pm
Posts: 50
Full Member
 

Why not get an 11-28 or 12-27 cassette and spend most of your time in the 50t ring? I've got a 52/34 compact on my road bike and I've used the 34t on only 2 occasions since last July. It took me a few months of perseverence to get used to pushing the 52t everywhere, but the old saying 'no pain, no gain' was never truer. Living in the Pennines, most of my longer rides (60-80miles) include around 6-8,000ft of ascent (according to Endomondo) and I average around the 16mph mark too.


 
Posted : 08/05/2012 10:43 pm
Posts: 1442
Free Member
 

what massive jump on the front?

[img] [/img]


 
Posted : 08/05/2012 10:47 pm
Posts: 41395
Free Member
 

42-52 is another comparison...doesn't suit your aim tho!


 
Posted : 08/05/2012 10:49 pm
 mboy
Posts: 12582
Free Member
Topic starter
 

what massive jump on the front?

That 47.1% jump between the 34 and the 50... Durrr! 😕

Knocked up a quick spreadsheet last night based on the calculations in the old hub gear spreadsheet I created a while back (if anyone wants a copy of either). Generally shifting up from the 34 to the 50 on the front is like shifting 4 gears on the back at the same time. Too much IMO.

How long have you had the bike btw? I did find the jump on the compact annoying at first, but now I find I shift down/up almost at the same time and it doesnt annoy me at all now, but everyone is differnt.

Year and a bit, though riding has been sporadic on it truth be told. Rode it loads when I first got it, then not for a few months, now gonna get back into it a bit more as I can't really afford the fuel to go MTBing so much these days (no trails within 15 miles of where I live really). Maybe I'll just get used to it too, but I can understand the desire for a triple in a lot of cases, less so for the spread of gears, more so just to stop massive ratio jumps when changing chainrings.

Why not get an 11-28 or 12-27 cassette and spend most of your time in the 50t ring?

Initially thought about this. BUT... The 12-27 only changes the top 2 sprockets. The ratios are thus...

27, 24, 21, 19, 17, 15, 14, 13, 12

For the 12-25 I have now it's...

25, 23, 21, 19, 17, 15, 14, 13, 12

The only 2 ratios that are changed, are the ones I rarely/never use on the 50T chainring. And though I'd perhaps like a 27T bailout for climbing on really steep stuff, it might also defeat the point a little.

Hence my reasoning on a 46T outer maybe, as it would drop the overall ratio, and mean I'd use the 17 (and maybe the 15) more on my current cassette?


 
Posted : 08/05/2012 11:01 pm
Posts: 1442
Free Member
 

That 47.1% jump between the 34 and the 50... Durrr!

sorry i thought you meant there was a big gap in your gearing when using either 50 or 34. when in fact they overlap a fair bit.

personally i don't have a problem as i instinctively shift the rear the corresponding 3 cogs the same time as the front so i'm in the correct 'next gear', i do it without thinking with just a slight reduction in pressure on the pedals, never had an issue with crunching gears/mis-shifts/dropped chains but then my gears are set up properly and i keep the drivetrain clean.


 
Posted : 08/05/2012 11:11 pm
Posts: 50
Full Member
 

Personally I just treat my set-up as 1 x 9, with the bonus of a 'get out of jail free card' 34t inner as an absolute last resort. From your original post (I only read the first page though) it seems to me that you need to increase your strength and dropping onto the 34t at the first sign of a slope is counter-productive to your aims. Rather than go down to a 46t outer I reckon you should get a 52t instead, swap your cassette as suggested and teach yourself to mash out the miles. It'll take a while to get used to it, but you'll feel the benefit down the line.


 
Posted : 08/05/2012 11:16 pm
 mboy
Posts: 12582
Free Member
Topic starter
 

My gear setup is faultless, can't complain at all about that, the Tiagra makes the equivalent MTB level Deore feel agricultural IMO. Never a missed shift, everything as it should be etc. Just seems I either need to get used to the ratios, or change them for something more favourable. Cos on a mountain bike, I've never had to shift more than one cog on the back to make up for changing up/down a chainring on the front, so to have to go up 3 cogs on the back at the same time as shifting from 34 to 50 up front, to be in the equivalent next ratio up still (or shift 4 on the back to stay in the same ratio) feels VERY odd to me.


 
Posted : 08/05/2012 11:23 pm
Posts: 0
Free Member
 

get some aero wheels and fast tyres. then you'll be in smaller sprockets (higher gears) when your on the 50t ring on the flatter sections. depending how good your current stuff is. and......ride harder.


 
Posted : 09/05/2012 3:50 am
Posts: 0
Free Member
 

My set up's a 50/34 11-28, I spend most time on the 34 on hilly rides and keep a cadence around 90. Use the 50 on descents.


 
Posted : 09/05/2012 6:07 am
Posts: 12148
Free Member
 

You can ride all day on the 39 from a standard 53/39.
The problem with compact is that have to use the 50, the 34 just isn't a riding gear if that makes sense?
And I know there is overlap between the two types, but I find the drop when you're 'suddenly' on a climb too big.
In hilly or undulating terrain I keep it in 39 and flick between three gears. I find it keeps fatigue at bay and my cadence remains reasonable.
39 is also useful in strong headwinds.
A few blokes bung a 27 on the back of their training bikes.


 
Posted : 09/05/2012 6:14 am
Posts: 0
Free Member
 

but I find the drop when you're 'suddenly' on a climb too big.

I always think the chains come off!


 
Posted : 09/05/2012 6:26 am
Posts: 25
Full Member
 

You're not on your own.

I've been having the same thoughts for quite a while.
I find that I'm at the bottom of the cassette on the smaller ring and the top on the big ring.

I've got used to changing 3 gears for a chain ring change and I'm trying to ride the bigger ring more but it doesn't feel right.
Compared to a mountain bike, road gears have far less difference between them - My reading of this was so you can find just the right gear but the massive difference in chain rings seems to be counter to this.

My current thinking is that I need to man up and ride in the big ring more.


 
Posted : 09/05/2012 9:45 am
Posts: 20314
Full Member
 

I hate compacts on road bikes as well. 50 seems just a fraction too high sometimes but 34 is way too low. 39/53 is perfect for me.

OP: It might be worth experimenting with the cassette a bit? Try changing to one with closer ratios, 11-23 or 11-25., it might help offset the big jump between the chainrings and make it easier to find that "just right" gear.


 
Posted : 09/05/2012 10:06 am
Posts: 12148
Free Member
 

I wouldn't worry about cadence or bigger gears.
If this sounds patronising then I'm sorry, but a good few riders that join us tend to spin furiously on the hills on their compacts. They don't seem to be getting anywhere and look knackered. I also think you have poor control when you are over spinning.
My advice (no pro coach here) is to ease off, relax, drop a gear and let the bike do the work and make smooth progress.
Of course having the bike and shoes properly set up is essential.

Edit; Also don't charge at the hills in an effort to get up em quick, settle in and wind it up.


 
Posted : 09/05/2012 10:23 am
Posts: 0
Free Member
 

i have to say having recently got a bike with tiagra compact setup i agree both about the quality of the shifting action and how disconcerting the switch between rings is. i'm now used to simultaneously changing ring and shifting two or three at the back to ease the difference a bit.


 
Posted : 09/05/2012 10:31 am
Posts: 91095
Free Member
 

I'm either too far down the cassette in the 34T ring all the time, or too high up it in the 50T

I had the same problem with compact. That and spinning out on descents. I hated it, so I went with triple.

It makes sense if you live anywhere near any kind of hill. Better shifting, better gear spread, better everything, and for a tiny increase in weight.


 
Posted : 09/05/2012 10:36 am
 will
Posts: 44
Free Member
 

39:53 is perfect I think. Very rare that the 39 gets used unless it's a steep climb. using either a 12:28 or 11:25 depending on wheels.

Having said that i have a 54 outer now as 53's were out of stock 😆


 
Posted : 09/05/2012 10:44 am
Posts: 75
Free Member
 

I went with a compact for the Pyrenees. Don't like the big drop to a 34 here though and swapped it for a 36 I had in the shed. Nicer, but probably equally go back to regular chainset.


 
Posted : 09/05/2012 10:52 am
Posts: 0
Free Member
 

The gear ratios on compacts are horrible imo, made even worse on anything bigger than a 11-25 cassette.

Changed my double to a compact some time ago and used to run a 11-27 but couldn't get on with it. Changed to a 11-25 which was a little better but in the end decided to go back to a double and I am a lot happier. I think changing to a 11-23 will get the ratios exactly where I want them.

I live in a reasonably hilly area too but don't find the lack of the 34 to much of a problem although some hills require my finest gear munching to get up the hill.


 
Posted : 09/05/2012 10:56 am
Posts: 16125
Free Member
 

I don't like the jump on my compact, either. Is swapping the inner ring to a 36T likely to make much difference?


 
Posted : 09/05/2012 11:02 am
Posts: 0
Free Member
 

39:53 here. Shift at the front with 2 at the back, what's the problem?


 
Posted : 09/05/2012 11:10 am
Posts: 0
Free Member
 

My set up's a 50/34 11-28

Same here on one of my bikes. Changing to the 11-28 from an 11-25 was very noticeable.

My other road bike wears a MTB long-cage mech and has 50/34 and 11-32.


 
Posted : 09/05/2012 11:27 am
Posts: 1014
Free Member
 

sram comact is 36-50. don't find it a big gap at all. only car park test rides on a std so not much to compare to though.


 
Posted : 09/05/2012 11:28 am
Posts: 91095
Free Member
 

what's the problem?

For me it was because on easier rides I was constantly shifting between rings, it was a right pain. Less overlap means more ring shifting I reckon.


 
Posted : 09/05/2012 11:38 am
Posts: 4333
Full Member
 

Im running a 39/50 with a 12/23 (old 8 speed).

I find the 53 too big so thinking about a 39/50 now.

I cant understand why anyone would need less than a 39 up front. Im not fast at the mo and with a 39 and 23 as my lowest gear i can get up anything. (checks knees for expolding cartilage)


 
Posted : 09/05/2012 11:56 am
Posts: 0
Free Member
 

I cant understand why anyone would need less than a 39 up front

'Cause God invented these things called hills and I'm old and unfit.


 
Posted : 09/05/2012 11:58 am
Posts: 4333
Full Member
 

I use to do hill climbs on a 42 and im not fit. But then im only 11 stone.


 
Posted : 09/05/2012 11:59 am
Posts: 91095
Free Member
 

Because some of us want/need to spin, rather than heave on the pedals. If I am out for a base training ride then hammering for 30 mins out of a Welsh Valley isn't what I want to be doing.


 
Posted : 09/05/2012 11:59 am
Posts: 0
Free Member
 

I cant understand why anyone would need less than a 39 up front.

Go on then. So they can ride up Hardknott pass after 100 miles in the rain this Sunday. I bet no one doing the FW is running a 39/23.


 
Posted : 09/05/2012 12:00 pm
Posts: 6289
Full Member
 

most of the above is why I stick with a triple chainset, especially good for the chilterns & what with me being a self confessed lover of granny rings too, oh & paying just £67.50 for an ultegra chainset from merlin helped 🙂


 
Posted : 09/05/2012 12:07 pm
Posts: 166
Free Member
 

was very glad of my compact in sierra nevada mountains last week, my mate on a standard struggled to keep his effort low enough to climb for 1.5-2hours without blowing up. I did have to make a bit of a consious effort not to just dawdle though!

Also i dont find the jump between the front rings a problem, I tend to just put a double (ie front and back)shift in at the same time and its a very clean change with quite a small effort jump


 
Posted : 09/05/2012 12:27 pm
Posts: 0
Free Member
 

sram comact is 36-50.

Since when? or have you changed yours?

SRAM force compact here, from 2010, chainrings are 50:34


 
Posted : 09/05/2012 12:37 pm
Posts: 0
Free Member
 

One of my colleagues who's much fitter than me and does a lot of sportives etc. borrowed one of my wheelsets for an event recently. That had an 11:28 cassette on it and the first thing he did after the even was order the same for his own wheels. He found it very helpful towards the end of the event, so even a reasonably fit rider might prefer lower gearing on longer & hilly days.


 
Posted : 09/05/2012 12:46 pm
Posts: 6616
Free Member
 

Gearing on the road is a lot more important than off road- or at least you notice it more as there are less other things to distract you and you pedalling action is smoother as you have less rocks to avoid etc.

Anyway you should spend some time and maybe try some other sprockets. Different cassettes are available and if you work out the gear inches you might find something more suitable. Might also be worth changing the rings at the front although you are more limited by what will fit your crankset. Closer spaced rings at the front and a narrower range casette at the back will help you find the right gear more often but at the expense of range.

You need to find something that suits you and where you ride.

I've never had a problem with a compact running a 12-27 on the back. I race on it, do sportives on it but then it suits me and where I live. I actually ride my cross bike on club runs and that is limited to a 46 up front and a 12 out back. It actually works really well as if the ride is easy I just do the whole thing in the big ring. Bit of a pain on the occassional fast downhill but I'm ok up to 35mph.

Contador switched to a mtb cassette during last years tour to help on the hills.


 
Posted : 09/05/2012 12:53 pm
 mboy
Posts: 12582
Free Member
Topic starter
 

I cant understand why anyone would need less than a 39 up front. Im not fast at the mo and with a 39 and 23 as my lowest gear i can get up anything. (checks knees for expolding cartilage)

Was going to say "are you Alberto Contador, and can I claim my £5?" Until I saw the following quote...

Contador switched to a mtb cassette during last years tour to help on the hills.

Explains how he rattled up the Galibier on his 53T ring then! 😯

ANYONE who makes outlandish statements about not needing anything taller than a 39/23 as their bottom gear, I can assure you you just don't ride anywhere with very steep hills. I'm sure you're pretty strong and can get up some fairly steep hills, but as davidtaylforth said, how would you plan on tackling the Hardknott pass, in places a 1 in 3 iirc? One of my friends is doing it, normally rides a 39/53 with an 11-21 or 11-23 for racing, but is taking a CX bike with a 30/39/53 triple and an 11-34 MTB cassette out back to make sure of getting up the Hardknott pass!

From the last few posts, beginning to think a Triple would make much more sense for me, especially given what oldgit said about staying in the 39T all day on his STD sometimes, but there's no way I could climb everything I would ride on a 39 and a 53 would get used almost never. Though I can also see why now that Tiagra has moved to 10spd (I've only got 9) that new Tiagra equipped bikes are coming with a 34/50 compact and 12-30 cassettes, or sometimes 11-28 fitted. Makes more sense. But a cassette with that range in 9spd will have pretty large gaps in the ratios.

Just one more quick question... Is 110BCD 5 bolt on a compact, the same as the 110BCD STD 5 bolt MTB chainsets of years gone by? Cos if so then I shouldn't have any issues finding a 46T outer to try out...


 
Posted : 09/05/2012 4:23 pm
Posts: 41395
Free Member
 

110 bcd is 110 bcd.


 
Posted : 09/05/2012 4:27 pm
Posts: 20314
Full Member
 

ANYONE who makes outlandish statements about not needing anything taller than a 39/23 as their bottom gear, I can assure you you just don't ride anywhere with very steep hills. I'm sure you're pretty strong and can get up some fairly steep hills, but as davidtaylforth said, how would you plan on tackling the Hardknott pass, in places a 1 in 3 iirc? One of my friends is doing it, normally rides a 39/53 with an 11-21 or 11-23 for racing, but is taking a CX bike with a 30/39/53 triple and an 11-34 MTB cassette out back to make sure of getting up the Hardknott pass!

Same here: I've always ridden 39/53 with either a 12-23 or 12-25 but when I did the Fred Whitton I used my CX bike with 34/48 chainset and a 12-27 cassette. 34:27 low gear was *just* enough. And I like climbing hills!


 
Posted : 09/05/2012 4:32 pm
Posts: 6325
Free Member
 

I like a triple but must admit to using a 28/38/48 with a 12/25 cassette.
The 28 is for gravelling but the 38 front does most hills, a touch lower than the road 39 and a 48 does everything else. Stick that on the 12 and its fine for everything on the flat, I never spin out. Downhills that are steep and long need no pedalling, partly as 40 plus is just plain moronic.


 
Posted : 09/05/2012 4:41 pm
Posts: 10953
Free Member
 

When I converted my SSCX into geared I went 34/46 with 12/27, I use the 34/27 to twiddle up a 1 mile long 1:10 hill that's close to home on my commute. I too struggle to keep a good chainline particularly when twiddling home after a 14hr night shift with the brain and zest of a snail. Horses for courses n all that jazz.


 
Posted : 09/05/2012 5:08 pm
Posts: 0
Free Member
 

I used to make fun of compact cranks, but they're actually good man. Better cadence. Compact cranks are the way to go. You know Basso uses compact cranks? So does Tyler Hamilton.


 
Posted : 09/05/2012 5:17 pm
Posts: 6289
Full Member
 

partly as 40 plus is just plain moronic.

You say moronic I say wuss


 
Posted : 09/05/2012 5:33 pm