58t Chainring for Carrera Virtuoso

Louis_Miller

I'm buying a Carrera Virtuoso tomorrow and want to change the outer chainring from a 50t to a 58t. Will the current mech handle the larger chainring or will i need to change that aswell? The gear system is Shimano ST2200 if that helps, i think if i just move the front mech up slightly on the downtube and reset the gears it will work but just thought i'd see if anone on here has any input.

One more question, is it possible to buy a single 58t chainring and replace the 50t on the chainset or will i need a whole new chainset?

nolf

Not sure if you can get a 58 tooth chainring and not quite sure why you need it....

I mean I never hit my top gear and think- if only I had more- as I'm usually going downhill and so just tuck in a bit more.
In sprints you won't be able to oush thyat size chainring, in track cycling you'd have to be a sporting god to push that with say a 15 tooth on the back.

Or you have a really really low cadence which will knacker your knees.

Even OldWelshman doesn't have a 58 tooth chainring

Louis_Miller

Well on my flatbar road bike at the moment i have 48t and on the ride i usually do has an approx. 5 mile descent and i always find my self running out of gears very early on and not being able to get over 30mph. I think the 2t step up isn't going to make that much of a difference and i've heard of someone running 58t and i reckon that'll make the difference i need to get down the descent a bit faster.

nolf

If you get a 52/53 with a 12 at the back, then spin a bit faster.

Try and keep cadence at 80rpm+

If you really want to get speed then get some drop handlebars so you can go in a more aerodynamic position.

nmcgann

Louis_Miller wrote:

Well on my flatbar road bike at the moment i have 48t and on the ride i usually do has an approx. 5 mile descent and i always find my self running out of gears very early on and not being able to get over 30mph. I think the 2t step up isn't going to make that much of a difference and i've heard of someone running 58t and i reckon that'll make the difference i need to get down the descent a bit faster.

Hmmm - 100rpm on 48x12 is over 31mph, on 50x12 it's 32.6mph. Should be enough with a bit of practice at spinning a higher rpm.

If you are stil determined to raise your overall gearing a cassette with an 11T cog and a 50T ring is a slightly larger gear than 54x12 and will be cheaper and easier than messing with the chainset.

A 58T ring would probably need a bigger inner ring to stay within the capacity of the front mech and the front mech may then not work too well as the cage curvature won't match the bigger ring properly.

Neil

banana_man

Yeah you want to be looking at your rear cassette, not your chainrings. I'm guessing the cassette on your carrera virtuoso will have a lower range of sprockets than your current bike and so you'll be able to reach a higher top speed anyway; i've never heard of anyone wanting or needing a 58 tooth chainring, it's sheer madness! Like Neil said, you'd have trouble finding a derailleur to match the curvature of a 58T ring and you'd never be able to fit one to a 39T(?) small ring because it would never shift between the two! I'd love to see this monstrosity if you do attempt it.

DavidTQ

I can see where the poster is coming from, Ive worked out I generally pedal at around 80 rpm comfortably with plenty of power to spare but not so much puff to spare, I could push harder along the level at the same RPM without much problem (I live in hilly area) but I would quickly tire spinning faster for any length of time Ive just not got lance armstrongs natural spinning advantages! My body is naturally tuned for power and stamina not for speed.

Im on a 30-39-50 with a 12-25 cassette and when going along the level find my self really spinning to get speed in top gear 90-100 rpm just isnt comfortable for me for any length of time.

I think going to a 53t ring and 11t sprocket at the back would give me an extra 4mph comfortably along the level, maybe Im kidding myself but I dont feel it would be straining to push that along the level. Certainly in my current top spinning at 80rpm I can barely feel any effort going into it along some of the long levels, and I actually like a degree of resistance to my pedals.

Im just a bit too lazy and tight to go and spend the money to gain a few mph, its not as if my 25 minute chair to chair commute is bad timing as it is, maybe next spring, and get some skinnier tyres to go with it...

Eat My Dust

I hit at least 38mph every day on a 50x12, obviously downhill, but not all that steep. Even on a slight decline I can reach 35mph. So I don't really see any need for anything bigger.

BTW the 38mph+ is before I run out of road, I'm not even spinning out, so I imagine I'd be hitting way above 40 on a good run.

formerlyknownasbonj

you can't even get 58t rings anywhere! the highest they go up to is a triathlon ring which is 56t...
I basically asked this exact same question on cyclechat, and the response seems to be either be content with the just over 30mph that you're probably going anyway, spin faster, get a cassette with an 11t top sprocket (and if you really want a 53t big ring), or a mix of all three of those.

DavidTQ

Eat My Dust wrote:

I hit at least 38mph every day on a 50x12, obviously downhill, but not all that steep. Even on a slight decline I can reach 35mph. So I don't really see any need for anything bigger.

BTW the 38mph+ is before I run out of road, I'm not even spinning out, so I imagine I'd be hitting way above 40 on a good run.

Thats spinning at around 120 rpm thats fine if thats what YOUR body works with, but not everyone finds 120rpm comfortable or even sustainable, 80rpm is a pretty good average cadence, some of us have muscle strength to spare for a little pedalling effort but not the lung capacity for sonic the hedgehog on a bicycle antics, 120 rpm, I wouldnt last many minutes at.

120RPM is high end cadence for Lance Armstrong, Im just not built or trained to pedal that fast for any length of time.

blackhands

formerlyknownasbonj wrote:

you can't even get 58t rings anywhere! the highest they go up to is a triathlon ring which is 56t....

MDT Do chairings over 60 teeth and TA do a 57. But, the chainset on this bike looks like a compact so would need a specially made chainring. Bearing in mind the cost of the bike, the likely cost odf a one off chainring would probably make it unworkable. I agree that a much better alternative is to go up a sprocket tooth - speak to Highpath Engineering.

Eat My Dust

DavidTQ wrote:

Eat My Dust wrote:

I hit at least 38mph every day on a 50x12, obviously downhill, but not all that steep. Even on a slight decline I can reach 35mph. So I don't really see any need for anything bigger.

BTW the 38mph+ is before I run out of road, I'm not even spinning out, so I imagine I'd be hitting way above 40 on a good run.

Thats spinning at around 120 rpm thats fine if thats what YOUR body works with, but not everyone finds 120rpm comfortable or even sustainable, 80rpm is a pretty good average cadence, some of us have muscle strength to spare for a little pedalling effort but not the lung capacity for sonic the hedgehog on a bicycle antics, 120 rpm, I wouldnt last many minutes at.

120RPM is high end cadence for Lance Armstrong, Im just not built or trained to pedal that fast for any length of time.

Rubbish!! spinning no where near 120rpm, more like 90 rpm. I did say down hill. I don't believe that calculations on gear size and rpm are anywhere close to accurate. It surely depends on how much energy/force you are putting down on the pedals.

DavidTQ

Eat My Dust wrote:

DavidTQ wrote:

Eat My Dust wrote:

I hit at least 38mph every day on a 50x12, obviously downhill, but not all that steep. Even on a slight decline I can reach 35mph. So I don't really see any need for anything bigger.

BTW the 38mph+ is before I run out of road, I'm not even spinning out, so I imagine I'd be hitting way above 40 on a good run.

Thats spinning at around 120 rpm thats fine if thats what YOUR body works with, but not everyone finds 120rpm comfortable or even sustainable, 80rpm is a pretty good average cadence, some of us have muscle strength to spare for a little pedalling effort but not the lung capacity for sonic the hedgehog on a bicycle antics, 120 rpm, I wouldnt last many minutes at.

120RPM is high end cadence for Lance Armstrong, Im just not built or trained to pedal that fast for any length of time.

Rubbish!! spinning no where near 120rpm, more like 90 rpm. I did say down hill. I don't believe that calculations on gear size and rpm are anywhere close to accurate. It surely depends on how much energy/force you are putting down on the pedals.

IF you were doing 90rpm at that speed with that gearing you are providing no forward power at all to be providing forward motion youd have to be pedalling at around 120rpm. The maths works because the moment the freewheel is "freewheeling" you arent powering the bike anymore. when you rear cog is spinning slower than the rear wheel even if it is turning its not adding forward power to the bike.

Garybee

My TT bike has a 53 X 11 top gear and that is plenty. I don't pedal with a high cadence in TTs either, the nearer you get to that 11t the larger each jump becomes because 1 single tooth becomes a larger percentage of the sprocket.

Having said that i'd love to turn up at my club 10 with a 58 'ring just to see the looks on people's faces. I would imagine i'd get one of 2 responces, they'd either be really intimidated or just laugh at me. The 2nd seems most likely.

Eat My Dust

DavidTQ wrote:

Eat My Dust wrote:

DavidTQ wrote:

Eat My Dust wrote:

I hit at least 38mph every day on a 50x12, obviously downhill, but not all that steep. Even on a slight decline I can reach 35mph. So I don't really see any need for anything bigger.

BTW the 38mph+ is before I run out of road, I'm not even spinning out, so I imagine I'd be hitting way above 40 on a good run.

Thats spinning at around 120 rpm thats fine if thats what YOUR body works with, but not everyone finds 120rpm comfortable or even sustainable, 80rpm is a pretty good average cadence, some of us have muscle strength to spare for a little pedalling effort but not the lung capacity for sonic the hedgehog on a bicycle antics, 120 rpm, I wouldnt last many minutes at.

120RPM is high end cadence for Lance Armstrong, Im just not built or trained to pedal that fast for any length of time.

Rubbish!! spinning no where near 120rpm, more like 90 rpm. I did say down hill. I don't believe that calculations on gear size and rpm are anywhere close to accurate. It surely depends on how much energy/force you are putting down on the pedals.

IF you were doing 90rpm at that speed with that gearing you are providing no forward power at all to be providing forward motion youd have to be pedalling at around 120rpm. The maths works because the moment the freewheel is "freewheeling" you arent powering the bike anymore. when you rear cog is spinning slower than the rear wheel even if it is turning its not adding forward power to the bike.

I still disagree. I hit 39mph the other morning, as I said before, downhill, but not that steep. I was no where near spinning at 120rpm, and would have easily hit 40+ if I hadn't run out of road. If I'm pedalling and still feeling resistance, then I'm still applying power. The maths surely only work for a completely flat surface. Otherwise I could give my skinny legged workmate Dave my bike and he could achieve the same speed on the same bit of road!!

graemetherunner

I run a 60 on my tandem with a standard durace mech - it copes fine, the "curvature" thing really isn't an issue other than asthetics.

When running this I leave the 39 inner due to frame clearance & if I used a long cage rear mech it would cope.
On other bikes I have made the inner a 52 & 60 outer.

having a larger ring means the need for 12 & 11 tooth sprockets is reduced & thats a good thing in my opinion as its smoother.

I can get ring of any sizes made up for any pcd at very reasonable cost, send me a pm if you need one.

Louis_Miller

Thanks for all the great replies guys, all this roadie jargon is all very new to me, what with talking about rpm and everything, being a downhiller for the last few years i haven't really paid much attention to the finer points of the bike, sure i'll get to grips with it at some point.

Anyway, picked up the bike today, took it out for a short 5 mile ride just to test it out as i was short on time and found that the extra couple of t's made a fair bit of difference, the smallest cog on the cassette is 12t. Going out on a ride tomorrow morning, going to be riding my usual route which is 27mile, usually complete it in 45 - 49 minutes on the flatbar so i'll see what difference it makes!

epicurus

If you can do 27 miles in 45 minutes then maybe a 58t chainring isn't such a peculiar idea after all.

nmcgann

epicurus wrote:

If you can do 27 miles in 45 minutes then maybe a 58t chainring isn't such a peculiar idea after all.

Yes, Chris Boardman still holds the 25 mile TT record set in 1993 at 45min 57sec

Neil

Garybee

Oh dear, there really are some fantastic claims made on cycling forums. If even half of those made on this forum were true England would be laughing if the TDF went to national teams.

drewster_70

Some pretty impressive speeds:

Verbrugghe's "prologue" record @ 36.8mph Boardman's "absolute" hour record @ 35.2mph Boardman's "25" record @ 32.6mph Sosenka's "athlete" hour record @ 30.8mph Guy on a flat-bar hybrid @ 36.0mph (and could go faster!)

Don't normally take the mickey out of people on forums, but I just couldn't resist this one

piedwagtail91

50 x12 at 38 mph is about 115 rpm. at least on my tyre size. http://www.kreuzotter.de/english/ecadence.htm i would suggest calibrating the bike comp. or getting a reliable watch

rdaviesb

Perhaps we are dealing in metric miles. Called Kilometres?

Louis_Miller

Haha, sorry about that, slip of the... er... fingers, was meant to say 45 - 49 minutes each way, 13.5 miles there and back