Which is better for climbing?

dauphin said:

Which one of these cranksets is better for climbing a big hill and why? Average grade of the hill in question is 13.5%.

48x38x28T or 50/39/30T?

The expert opinion, is that most riders should not drop below 60rpm cadence. But best climbing cadence, depends on the individual. Select a crankset and cassette, that gives you this, realizing that a double weighs less and is less complicated, than a triple. Since every climb, has a descent, you also want a high gear that allows you to descend at the speed you want, without too high a cadence. Before, you only had to choose a Standard double or triple crankset, plus a cassette. But now, there are compact cranksets, that expand your options. Not all, but most requirements that use to require a triple, can now be accomplished with a double, compact crankset.

edited for my own stupidity!!

dauphin said:

Which one of these cranksets is better for climbing a big hill and why? Average grade of the hill in question is 13.5%.

48x38x28T or 50/39/30T?

The 48.38.28 sounds like mountain setup to me. A traditional road FD won't work with that crank.

What configuration do you have on your rear cassette?

Thanks for the reply. My Bianchi has a triple chainring of 50/39/30T with Shimano 10spd rear cassette 12/27T. This particular hill is part of an upcoming century (Sept 16) and it goes pretty much straight up for 1.75 miles with the average being 13.5%...parts are worse than that!

The choice of crankset depends on you and how fast you can ride up the hill.

The 48/38/28 will give you lower gearing and therefore it will be "easier" to pedal and travel slowly. By contrast, the TdF guys use a 39/53 double for climbing some significant slopes. So really, you need to look at your level of fitness, and climbing ability and make your choice accordingly. If you have bad knees from some other sporting activity (like I do) you might find the lower gearing better as it will minimise pressure on your joints.

As far as weight advantage goes, the difference. for example, between a double and a triple in the Ultegra range is 117g. Which is irrelevant for all but the most elite cyclists.

And 48/38/28 is a valid road setup (although it may well exist on mountain bikes as well) and Shimano road FDs will work with that setup.

dauphin said:

Thanks for the reply. My Bianchi has a triple chainring of 50/39/30T with Shimano 10spd rear cassette 12/27T. This particular hill is part of an upcoming century (Sept 16) and it goes pretty much straight up for 1.75 miles with the average being 13.5%...parts are worse than that!

I know this doent help at all but I wish I had that hill by my house-whoo hoo!! Just go as wide as you can in the hairpins!!

One thing-you'll gain more with changes in the rear cogs than changes in the chainrings. See if you can get a 13-30 cassette.

This first two times I attempted the hill were on a hybrid with the 48x38x28T triple. Mind you, I was only going about 5-6 mph in the lowest gear to make it up this stretch. I had a tougher time with the 50/39/30T Bianchi ...but that could also have been due to the heat and fatique from early training sessions.

dauphin said:

Thanks for the reply. My Bianchi has a triple chainring of 50/39/30T with Shimano 10spd rear cassette 12/27T. This particular hill is part of an upcoming century (Sept 16) and it goes pretty much straight up for 1.75 miles with the average being 13.5%...parts are worse than that!

I think your 30/27 low is about as low as practical on a road bike. For the 20-25% wall hairpins, might be tempting to have a 34 MTB cassette in back, but then you've got to carry it and a MTB RD around all the rest of the time.

I use a 30/25 low here. My thinking is that when you hit the 20-25% "wall" hairpins, you can't have low enough gear to maintain that desireable 60 cadence anyway (unless you're a pro-class rider with 500 watts of sustainable power). You'll have to get out of the saddle on the steep walls since the front wheel lofts off the ground if you're seated. As a result, looking for the lowest possible gear doesn't seem worth it to me.

Don't worry about having to get off and walk either. If the climb is late in the century, and the hairpins are as steep as you say, I don't think you'll be alone. I'll predict plenty of stronger guys on doubles will be walking.

dhk2 said:

I think your 30/27 low is about as low as practical on a road bike. For the 20-25% wall hairpins, might be tempting to have a 34 MTB cassette in back, but then you've got to carry it and a MTB RD around all the rest of the time.

I use a 30/25 low here. My thinking is that when you hit the 20-25% "wall" hairpins, you can't have low enough gear to maintain that desireable 60 cadence anyway (unless you're a pro-class rider with 500 watts of sustainable power). You'll have to get out of the saddle on the steep walls since the front wheel lofts off the ground if you're seated. As a result, looking for the lowest possible gear doesn't seem worth it to me.

Don't worry about having to get off and walk either. If the climb is late in the century, and the hairpins are as steep as you say, I don't think you'll be alone. I'll predict plenty of stronger guys on doubles will be walking.

The climb takes place about 24 miles into the ride. The entire ride features 11,000 feet of climbing.

rayhuang said:

I know this doent help at all but I wish I had that hill by my house-whoo hoo!! Just go as wide as you can in the hairpins!!

One thing-you'll gain more with changes in the rear cogs than changes in the chainrings. See if you can get a 13-30 cassette.

Bingo!

One of the reasons the Pro's go with 53/39 is because they will change cassette to suit the stage du jour.

It's nothing but hill's and mountain passes where I live and you find many riders using mountain cassettes on the rear and a big ring triple or compact on the cranks and they swear by it.

dauphin said:

Thanks for the reply. My Bianchi has a triple chainring of 50/39/30T with Shimano 10spd rear cassette 12/27T. This particular hill is part of an upcoming century (Sept 16) and it goes pretty much straight up for 1.75 miles with the average being 13.5%...parts are worse than that!

You can get a 28t or even a 26t granny with a 74BCD to fit on your existing crankset ... the chain may drag on the rear edge of the front derailleur if you have the chain on the granny and one of the smaller gears; but, it shouldn't if you only have the chain on the granny when you are using one of the larger cogs.

The 26t may NOT be a good choice unless you get a "chain minder" ... heck, you may want to get a "chain minder" to use if you get a 28t OR even for use with your 30t ... whether you need one of those "chain minder" gizmos depends on how well the front derailleur was/is set up.

dauphin said:

Thanks for the reply. My Bianchi has a triple chainring of 50/39/30T with Shimano 10spd rear cassette 12/27T. This particular hill is part of an upcoming century (Sept 16) and it goes pretty much straight up for 1.75 miles with the average being 13.5%...parts are worse than that!

That hill looks sweet. May I ask where that is?

dauphin said:

The climb takes place about 24 miles into the ride. The entire ride features 11,000 feet of climbing.

Boy, this sounds like Sonora Pass territory.

lw

I'd go with a larger cassette. If not, can you just change one chainring, the granny gear? If you can just find a 28 tooth that will fit that it would make it easier.

dauphin said:

Which one of these cranksets is better for climbing a big hill and why? Average grade of the hill in question is 13.5%.

48x38x28T or 50/39/30T?

On your Bianchi, you have to spin 57rpm to "maintain" 5mph. On the hybrid, it would depend on the cassette ratio, but with the same 12-27, you would only spin 4rpm more. While every little bit helps, it wouldn't be worth it if the hybrid weighed much more. Pure speculation, but I expect you would have to generate the same watts or more, on the hybrid. You are probably the only one that can decide if it's worth the expense and trouble, to gear lower.

jsull14 said:

That hill looks sweet. May I ask where that is?

That is Iowa Hill part of the Auburn Century. It's coming up from the American River outside of Colfax, CA.

Where can you get a 10 speed mountain bike cassete???????????????????

Or do they have 9 speed road bikes.

lwedge said:

Bingo!

One of the reasons the Pro's go with 53/39 is because they will change cassette to suit the stage du jour.

It's nothing but hill's and mountain passes where I live and you find many riders using mountain cassettes on the rear and a big ring triple or compact on the cranks and they swear by it.

dauphin said:

This first two times I attempted the hill were on a hybrid with the 48x38x28T triple. Mind you, I was only going about 5-6 mph in the lowest gear to make it up this stretch. I had a tougher time with the 50/39/30T Bianchi ...but that could also have been due to the heat and fatique from early training sessions.

[font=Verdana]Ah….. this means you have already answered your own Q. Certainly is a fair climb though. [/font]

[font=Verdana]If I’m correct your 28/26 Sirrus with its 28 mm tyres would have the same rollout per crank revolution [30 mm diff] to your 30/27 with 23 tyres. I’ll also assume that the Bianchi is a tough lighter, but in any case the gearing is for all intent & purposes the same.[/font]

[font=Verdana]Surely though the 30 speed would have to be preferential over a 24 speed.[/font]

[font=Verdana]BTW I don’t think of a Sirrus as a hybrid, a flat bar road bike IMO is a more appropriate name. Specialized bracket it with their road bikes. [/font]

11ring said:

Where can you get a 10 speed mountain bike cassete???????????????????

For the time being, if you want a pseudo-MTB 10-speed cassette then you'll need to buy a 9-speed LX cassette (11-34 OR 11-32) and unstack it. You'll need to cannibalize the LX cassette for one-or-more of the larger cogs.

There is a high probability that you cannot use a larger cog than 32t (which is a lot more than the conservative 27t spec'd size by Shimano), but may only be able to use a 30t ... if there is a 3.0cm offset between the rear derailleur hanger bolt & your rear axle (c-c), then you should be able to use a 32t cog with a Shimano rear derailleur, BTW; but, no guarantees!

I'm currently using an 11-34 & standard 52/39 crank on one ROAD bike with an Ultegra 6503 rear derailleur, but THAT involved some tweaking ...

OBVIOUSLY, you will need to remove one of the smaller cogs for each larger cog you insert when you restack the cassette AND the 10-speed spacer will go between the LX cog & original 10-speed cassette that you continue to use.

The rear derailleur can easily accommodate an 8-tooth gap ... so, if you currently have a 12-25, you mght/should be able to simply piggy-back the 32t onto the cassette AFTER the 25t, and remove the 13t (?) or 14t cog.