More gears please!

[dhd.evans]

My Triban 3a has 24 gears, which is grand, but I sometimes find myself coming down hills at speed and even at the hardest gear pedalling manically unable to gain more speed.

The question is, can i upgrade to get more gears and, if so, what kind of work would I/my LBS have to do?

 

[MisterStan]

My Triban 3a has 24 gears, which is grand, but I sometimes find myself coming down hills at speed and even at the hardest gear pedalling manically unable to gain more speed.

The question is, can i upgrade to get more gears and, if so, what kind of work would I/my LBS have to do?

What is the range of your cassette? You could change that (would mean a new chain too) for a different range. This would be the simplest and quickest fix.

 

[KneesUp]

The quickest and easiest way would be to change the largest chainring to a bigger one, assuming they are bolted on rather than riveted.

20 minutes work tops, and that's if the chain is fiddly to break/re-connect.

 

[HovR]

How many teeth are on the largest sprocket on the front, and the smallest sprocket on the back?

 

[Canrider]

Triban 3a should be a 50/39/30 triple on the front, and the pictures look as if it's bolted on, so that could be increased to a 52 or 53 big ring. No idea what the cassette holds in it, I'd guess a 11-32 or 11-28?

But, going from 50 to 53 will only increase your speed (on the flat) by 2-3 mph at 120 RPM (figures from Sheldon Brown's calculator http://sheldonbrown.com/gears/). So the question becomes: Exactly how much more speed did you need going downhill?

 

[HLaB]

Whats your smallest cog at the back? If its a 12t the cheapest way would be to change it for a 11t cassette and it would be most effective. The next step would be to investigate whether or not you could make your big front ring bigget (ie 50 to 52or 53). FWIW, the fastest I have been this year (45.6mph) was on a borrowed cyclocross with lower gears than on my other bikes, its more to do with technique IME.

 

[KneesUp]

Probably need to move the front mech upwards slightly if it touches a bigger chainring.

Half an hour then. And that includes the cup of tea

 

[dhd.evans]

See, this is helpful stuff. I peaked at 46mph this morning on a hill whilst on my aeros (at least Strava tells me this. It sure didn't feel that fast.) but I really felt like I was busting my gut.

This sounds like an easy enough fettle, although will require tuning. I'm going to ride it over the autumn without any changes and then when it gets to winter and I can convince my other half that I require new bits to make it through the dreadful weather i'll opt for this. Thanks to all for input.

 

[HLaB]

See, this is helpful stuff. I peaked at 46mph this morning on a hill whilst on my aeros (at least Strava tells me this. It sure didn't feel that fast.) but I really felt like I was busting my gut.

This sounds like an easy enough fettle, although will require tuning. I'm going to ride it over the autumn without any changes and then when it gets to winter and I can convince my other half that I require new bits to make it through the dreadful weather i'll opt for this. Thanks to all for input.

If it was recorded on an iphone it probably wasn't accurate, if not chapeau and it does sound like you need a bigger gear

 

[4F]

If it was recorded on an iphone it probably wasn't accurate, if not chapeau and it does sound like you need a bigger gear

Indeed, my iphone on Strava had me with a top at 40 this morning however I can state that no way was I going that fast fixed...

 

[T4tomo]

If you can truly get to 46mph then just freewheel after that. I wouldn't change teh chainrings, that will only put you in trouble going up hills.

 

[KneesUp]

If you can truly get to 46mph then just freewheel after that. I wouldn't change teh chainrings, that will only put you in trouble going up hills.

The OP only needs to change the big one - there are two others that can be used at other times - big one for downhills, middle one for the flat and little one for uphill.

 

[Rustybucket]

Sorry to gatecrash this thread, is there a guide to gearing anywhere? Ive just bought CB team carbon & find it a struggle to get up hills - Do I need to just get fitter or change the gearing?

Thanks guys

 

[KneesUp]

Sorry to gatecrash this thread, is there a guide to gearing anywhere? Ive just bought CB team carbon & find it a struggle to get up hills - Do I need to just get fitter or change the gearing?

Thanks guys

What gearing has it got? I'm swapping my 52/42 for a cheap compact triple because it's too high as it is for where I live. It's easier to swap that than try and find a 5 speed free-wheel with a decent range.

I'd say if you can 't ride at 60+ rpm in bottom gear, your gearing is too high. If you can just about ride the hills anyway, I'd guess you'd get fitter so may be ok. In my case the gearing is so high/local geography so unforgiving/I am so unfit that I can't get up some of the hills near here, hence the imminent change.

 

[Rustybucket]

Im assuming its SA Gossamer compact crankset (50/30) - as thats what its meant to come with? not sure what the numbers mean???