Front Triple Derailleur - can it be done?

[howlingwind]

Hello All

Fairly new to this malarky and a friend has signed me up for Etape 2009 - now want to buy this bike Kiron Scandium 2009 http://www.wiggle.co.uk/p/Cycle/7/Kiron_Scandium_2009_Road_Bike/5360037396/

But I have been told a triple derailleur would be a good choice due to numerous climbs etc - the bike however is a Compact - is it possibel to change the 2 for a triple up front? if yes what else would need to be done? and then is this expensive or not?

Big thanks in advance to anyone that can help me - much appreciated and then if anyone can answer this one I will sign over everything I own to them - why no matter what direction I ride in is the wind always in my face?

Kindly

Howling Wind

 

[GrahamG]

It's a bit more complicated than that.

First of all, the compact crankset offers you almost the same range of gears as a triple so you won't really gain a much lower/easier gear (the only issue I have with compacts is the jump between big and little ring on the chainset).

You would have to change the chainset and bottom bracket, the front derailleur, the rear derailleur and possibly the STI gear leaver if not triple compatible. So basically not cost effective for minimal improvement.

Just go and test ride a couple of road bikes with a compact and a triple set up and see which you prefer. There are all sorts of pros and cons but most are subjective so I don't see the value in listing them all, however here are some of the things to bear in mind:

- Indexing/trimming/shifting the front mech si a tiny bit more hassle on a triple, particularly trimming to avoid rub with Shimano shifters - Campag shifters are golden for triples.

- Shifting/indexing at the rear is a little compromised (not so crisp/quick/smooth) as a larger 'long cage' rear derailleur has to be used due to chain length and large difference between the big and small chainrings on the crankset.

- Compact cranksets have a large jump in the number of teeth (commonly 14-16t difference: 50 teeth on the big ring and 34 or 36 teeth on the little ring) this means that maintaining close gear ratios when moving between the two requires making a lot of gear changes at the back to compensate. How much of a problem this is depends on the day-to-day riding terrain as well as your own preferences which you will develop over quite a short period of time!

 

[howlingwind]

Thank you

Blimey alive - something told me it would not be easy!!

So there is in your opinion little extra granny power from a triple to a compact?

Many thanks for the tips

I will go and ride a few

Kindly

Bill

 

[RedBike]

It's all do with ratios.

Your compact crankset probably has an inner ring of 34 and an outer of 50. Whereas a triple will probably have 30,42,53.

Therefore if you ran a compact with an 12-25 cassette...
your lowest gear will be 34/25 (1.36) compared to a triple having a lowest gear of 30/25 (1.2)

However, if you ran a compact with an 12-27 cassette you would then have a lowest gear of 34/27 (1.26), nearly the same as you would have with a triple!

The easyiest and probably the cheapest way of getting low gears is to change the cassette. (With larger cassettes you might need to change your rear derailler)

Changing to a triple will require a new chainset £50/£75, bottom bracket, £20, cables, £15 probably a new rear mech £30, new chain £15 and if maybe even new shifters. Including the cost of labour you're looking at the best part of £200

 

[fossyant]

Hello All

Fairly new to this malarky and a friend has signed me up for Etape 2009

Bloody hell - some friend......... when you are new to it all..... crikey..... get the training in.....

As posts above - it's costly to buy the bike then go triple, plenty of other machines out there !

 

[RedBike]

Given the choice I would probably go for the Kiron. (My only reservation is i've never seen / heard of them!)

However this is also worth a look.
http://www.planet-x-warehouse.co.uk/

You could easily sell the dura-ace chainset form this, buy a compact 105 (like on the Kiron) and have enough money left over to put towards getting someone to fit it for you.

 

[jay clock]

I agree with the comments about replacing the cassette and adding a compact chainset A 12-27 with 34 at the front would be ok and avoids the problem of changing the front mech

You need to check what type of bottom bracket there is, but this looks like a decent chainset http://www.wiggle.co.uk/p/Cycle/7/Shimano_105_5600_Hollowtech_II_Compact_Chainset/5360038020/

You would be able to sell the other chainset on ebay....

I did exactly that with my road bike as I found the 53/39 too hard!

 

[alecstilleyedye]

i went through the whole double to triple thing a few years ago. it was more cost effective to buy a whole groupset, so the whole bike got upgraded from part sora to full tiagra.

i have never regretted it, and i now have a bike that can handle the high mountains and go at 30mph on the flat with gears for all conditions in-between. the only limiting factor is the rider…

for cheapness, definitely just change the rear cassette.

 

[ASC1951]

i ..... go at 30mph on the flat .... the only limiting factor is the rider….

Blimey! What speed will you do when you aren't limited?

 

[monnet]

Those who know my postings will know that I will advocate getting the triple. Lots of pros and cons but I'd say the biggest pro to a triple in this case is the small matter of Mont Ventoux. The ratio difference between bottom on a compact and bottom on a triple may only be a couple of inches but on the slopes of Ventoux, with 100miles already in your legs you are certain to be glad of the lower ratio (and probably be wishing a quadruple chainset had been invented to go with the Campag 11 speed). Get training- as Alec says the only limitation is the rider.

 

[RedBike]

I've ridden MTt. Ventoux but never done the full Etape. (Not too sure I could).

Mt Ventoux isn't actually 'that' steep. I think the max gradient is about 10%. It's not hard finding longish hills as steep or steeper than this in the UK.
However, Mt. Ventoux isn't longish. It's never ending! It's not the steepness of the climb thats the problem, it's the length. There's nothing like it in the UK.

Have a quick look at this video. It's not on a bike; but it does show nicely just how long the climb is.

View: http://uk.youtube.com/watch?v=jW8Ggcwo0WU&feature=related

 

[jimboalee]

Get the triple.

 

[yello]

Yep. Stop messing around with this idea of buying a compact and (expensive) swapping of components to make it a triple. Just get the triple to begin with. You're not compelled to use a granny gear but I'm guessing you'll be thankful of it when your dragging yourself up climbs. Good luck!

 

[jay clock]

Stop messing around with this idea of buying a compact and (expensive) swapping of components to make it a triple. Just get the triple to begin with

The point is that that bike is not available with a triple, so any purchase requires changing the chainset etc

Have a quick look at this video. It's not on a bike; but it does show nicely just how long the climb is.
http://uk.youtube.com/watch?v=jW8Ggc...eature=related

At 8m20s it sounds like a female voice in the car says f*ck as they see the cyclist come round the corner

 

[yello]

The point is that that bike is not available with a triple, so any purchase requires changing the chainset etc

Oh get out of here I'll be more explicit then - buy a bike with a triple groupset!

There are plenty of decent bikes out there to choose from. It makes no sense whatsoever to go buying a brand new bike (perhaps even your first?) then swapping out components before you've even ridden the darn thing!