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Crankset change


By daveh - Posted on 22 February 2012

I currently have a Shimano 105 compact crankset on my roadie (50/34). I bought new wheels as the cones on the old low-ish end Shimano set were pitted badly so seemed like a good excuse. Bought a new cassette and chain but thought I could get away without replacing the chain-rings but it is slipping badly when I put the power on, especially when standing, so assume that they need to be replaced as well (I probably left the old chain on too long so my fault).

As the price of replacing both chain-rings comes in at not all that much less than replacing the whole crankset should I go for something like 50/39? I do use the 34 but am definitely a lot fitter than when I bought the bike and am wondering if I should bite the bullet and move away from the compact crankset and will that improve my fitness or will I miss the compact too much.

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Normally it goes 53/39 and 50/34, from memory?

Me being an old fart, I'd be sticking with the compact ratios, going the taller ratios doesn't gain you all that much and I think 50/11 is taller than 53/12 anyway. Unless you're planning on entering road races, then the 53 top gear might be handy.

We all have periods off the bike for one reason or another (work, injury, family) where our fitness comes down a few notches more than we'd like, having a (slightly) easier entry point removes an excuse for procrastinating about getting back on the bike. Eye-wink

I would only ever consider a compact if I was climbing in the Alps for example, but even then I would prolly just stick a 28 tooth cassette on and go with that.

For around Sydney, including trips to the Southern Highlands where there are serious amounts of climbing involved, I have never seen the need for a compact.

Run a 53 and go do Hill Repeats up Bobbo in the Big Ring and tell me you dont get fit. It will help riding marathons when you have some long piece of fireroad and you are able to spin at 100rpm in the 42 x 11 cause your so used to a bigger gear on the road.

I have just moved from a standard with a 28 to a compact and am loving it. With the std crankset and the 28 cassette, I would often find that the differences between the cogs on the cassette were too big so I either was at too low a cadence or too fast a cadence while pedalling seated. Very annoying!

Firstly let me state that I love hills and climbing, especially long seated climbs (e.g. up from Brooklyn Bridge to Pie in the Sky, Bobin Head, Akuna etc). I love having the extra gears to spin while seated, but on the downhills, I very rarely miss having a bigger front cog as on most the descents, the bad road surfaces and windy roads mean that don't run out of gears.

As for getting fitter as a result of the bigger rings, you can quite easily find a similar resistance combination to train at a low, muscular cadence if you wish, but spinning up the hill at a high HR is also a great way to improve fitness and to cycle far more efficiently.

When descending I am always in the 53x11 and am using it, so yeah and for racing in A Grade, 53 is a must.

Nah.. unless you're doing a downhill sprint, 53x11 isn't a must. 50x11 is a bigger gear than 53x12 - 50x11 is good enough for us mere mortals

Ok, so although I would like to think that I will get to Logan's level I am not exactly there yet! Sounds like replacing the chain-rings and saving even a little cash is the go at this stage. When I start to race (*cough* *splutter*) I'm going to use that as an excuse to buy a whole new bike!

Thanks for the advice, as always it's horses for courses as expected.

Not sure where you are sourcing your chainrings but maybe look at alternative replacements other than the original manufacturer (Shimano) such as Specialites-TA
http://www.specialites-ta.com/gb/index-gb.php

If sourcing overseas, this site may be useful (although not foolproof!)
http://frugalrouleur.com/

Watch out for postage charges though. Evans seem pretty good for that at the moment with free postage on orders over about $80.

I've got the compact gearing on my Cadent and love it.

......but I think it is worth noting that the people who have used both do seem to prefer the compact and that the people who have never tried a compact seem against it. I guess it is a little bit like the 26 vs 29er argument where most people who have tried both are now riding 29er's and those who are all for 26 inch bikes have often never tried a 29er. Interesting Eye-wink

www.gear-calculator.com/
is an awesome site for visualising the comparison of gear setups.

It's hard to say if you'll miss the compact.
I didn't really find much difference between a compact and a big ring with 11-28, but a mate at work took my advice to go big and now he wants to go back to a compact. He's not weak either.
I've now got a 12-25 and I do miss the 11 occasionally on a fast descent.

I did run a 53/39 when I bought my bike, I changed it to a 50/34. Benefits are I tend to ride more (including hills) in the big ring now. Could I change back to the 53/39, probably!! But will potentially leave the compact on and change the cassette. Note i did run a 28, but found the skip down to 24 didn't suit my ability so changed to a 25 cassette, but will potentially purchase a 23 to obtain better steps in the middle.

Just food for thought here.
I reckon there is no better or worse in this case, some people like compacts better, others prefer 39/53. What I can say is that when I tested a bike with a compact, I did not like the bigger jump between chain rings, but that’s probably because I was used to 39/53.
I currently live in Melbourne in a quite hilly area, so when I bought my road bike I was struggling to climb some of the steep hills, so I bought a 11-28 cassette, what really helped. After several months I was really used to the 28 option at the back and was still struggling a little bit to maintain an acceptable cadence on some of the hills, but I was riding with some people weaker then myself that were using 12-25s and since I had one laying around I decided to try it again.
Was it harder? Hell yeah. Was it impossible? Hell no.
So I’ve been using the 12-25 since then and I ride in a place with several double digit gradient hills and this has made me stronger. Most people, including myself, if an easier option is available, will take it even though it is not required and we will get used to it and truly believe we are on the limit.
So, if you are really strong mentally, are happy with the compact and ride places where it is really required, keep it and only use the easier gears as a bail out option, otherwise get a 39/53 as not having the easy option will make you stronger in the longer term.
Cheers,

Leo.

If there is an easier option then it can be too tempting to take it. For the cost I think I'll just still with replacing he chainrings and try to remain disciplined with not taking that easy option every time! With regards to replacing the chainrings, I can obviously buy any brand 110mm 10sp chainrings. What is people's opinion of different brands? Seems that Shimano is pretty expensive compared with FSA and some others. Is that because they are genuinely that much better than the others or just because it's Shimano?

I have been using a compact on my general and race bike with either 12-25 for general and 11-23 for racing on the back ... until recently it was fine , now I find myself in Masters B grade and at Eastern Creek with a long down hill sprint finish the compact and 11-23 was not quite up to it , every other course is not a problem ( or my legs are not up to making it a problem !)

I just changed my FSA SLK-Light compact crank to an Ultegra 52/39 ( good price at Chain Reaction - 1/2 the FSA cost) . Weighed them both and the FSA is lighter by 60grm - but you pay a lot to save that

Cant detect any difference in riding between FSA and Ultegra

So long as the alloy is 7075-T6 on both there's not a lot of difference in service life. Shimano might shift more smoothly.

Specialites-TA & Stronglight both have good rep in Europe.

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