Touring - Change from triple to a double chainring?

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I have a 27 speed (Shimano Ultegra) and am switching from a 9 speed cassette to a 10. Here's my question.....On my upcoming long tour, with a Bob trailer (trlr and cargo 45 total lbs), would it be OK to go to a double front chainring. Without a trailer I never use the small sprocket and my 800 mile 8 day ride only has 20k of total elevation gain. I am in strong aerobic condition. Thanks for any opinions. Raydog
The Smokester
03-06-10, 08:16 PM
Not enough information. How many gear-inches do you have now that you use and how many will you have after the switch. And how much weight is added for the tour. After that, it's just a simple calculation.
gorshkov
03-06-10, 09:53 PM
My question is, why do you want to use a double? Since you already have the triple, I would stay with it. According to Sheldon Brown (http://www.sheldonbrown.com/speeds.html), a 10-speed chain should work with the current (9-speed designed) crankset.
To the best of my knowledge, the largest cog on a Shimano 10-speed cassette is 27 teeth, which with a compact double crank gives you a lowest gear of about 34 gear-inches, which imo is not low enough for loaded touring. For comparison, most purpose-built touring bikes have a low gear around 20 gear-inches.
My question is, why do you want to use a double? Since you already have the triple, I would stay with it. According to Sheldon Brown (http://www.sheldonbrown.com/speeds.html), a 10-speed chain should work with the current (9-speed designed) crankset.
To the best of my knowledge, the largest cog on a Shimano 10-speed cassette is 27 teeth, which with a compact double crank gives you a lowest gear of about 34 gear-inches, which imo is not low enough for loaded touring. For comparison, most purpose-built touring bikes have a low gear around 20 gear-inches.
That is the exact info I was looking for, and in the Mechanical section someone reminded me how much it would screw up the trip if I ran out of gear on the hills......thanks much. Raydog
vegenaise
03-07-10, 12:20 AM
i run a compact double with a 10 in the rear. never had a problem with gearing on my tours. you'll make due with what you have. don't sell yourself short and settle in to mediocrity as most of the 50 year old tourers here have. man up and go for it.
dewaday
03-07-10, 05:44 AM
i run a compact double ...
gears are for sissies
i run a compact double with a 10 in the rear. never had a problem with gearing on my tours. you'll make due with what you have. don't sell yourself short and settle in to mediocrity as most of the 50 year old tourers here have. man up and go for it.
That whole "Right tool for the job" thing is way over rated! Why use the triple you have now when you could beat yourself up with a double? :twitchy:
kayakdiver
03-07-10, 07:44 AM
i run a compact double with a 10 in the rear. never had a problem with gearing on my tours. you'll make due with what you have. don't sell yourself short and settle in to mediocrity as most of the 50 year old tourers here have. man up and go for it.
Why use a compact double and not a fixie weak sauce? Man up mediocrity.
gears are for sissies
real men ride unicycles
real men ride unicycles
Unicycle with clip-in pedals, backpack and helmet with propeller on top.
mattbicycle
03-07-10, 08:44 AM
I'm not technically-minded at all and only know what feels right for me.
I can understand the dilemma if you're considering whether to suffer the expense and trouble of going from two chainrings to three. But if you've already got three, and the ten speed is compatible, I can't see any value in short-changing yourself. Are you hoping to save weight or make the gearing set-up simpler? I must be missing something here. Perhaps I am in over-my-head commenting... It just seems like taking the light bulbs out of your car's head and taillights because you aren't planning on driving at night :)
If you've got a burning desire to change something in preparation for the trip, buy a better saddle, upgrade the tyres or something else that will be useful!
Bekologist
03-07-10, 09:20 AM
on your upcoming long tour, would it be ok to go to a double front chainring combo? why, sure.... just 20,000 elevation gain :eek: a double is definitely what you want for this.
why do you want to do go to the double again? You never use the little ring?
Pretend you don't have it, until you absolutely, positively need it - that'll be fun!
OK, this thread is funny, sarcastic, cynical and most importantly....informative. Why am I considering going to a double? The complete Ultegra (double front, 10 rear) system I just acquired is black chrome and my existing Ultegra (triple front, 9 rear) is polished silver handles. I realize that cosmetics/bling is the least important issue in the world compared to function/efficiency.
The shapes of the shifters are the same, just the finish is different. The reasons I was asking about going to the double are based on the racers I ride with on Computrainers (4 x's wkly). They all have doubles and I was asked once why I run a triple. I've been around bikes off and on for years BUT not bike culture much. I'm thinking the inquiry about my triple was grounded in, "real bikers don't need little chainrings, you whuse" elitism.
I really don't care if my handles don't match for this trip, the fact that I'm a 200 pounder with a trailer going 800 miles across Nevada and Utah should make it obvious to me.....keep the freeking triple. Doyle
10 Wheels
03-07-10, 09:56 AM
How many of the racers were pulling a trailer?
blaise_f
03-07-10, 10:43 AM
OK, this thread is funny, sarcastic, cynical and most importantly....informative. Why am I considering going to a double? The complete Ultegra (double front, 10 rear) system I just acquired is black chrome and my existing Ultegra (triple front, 9 rear) is polished silver handles. I realize that cosmetics/bling is the least important issue in the world compared to function/efficiency.
The shapes of the shifters are the same, just the finish is different. The reasons I was asking about going to the double are based on the racers I ride with on Computrainers (4 x's wkly). They all have doubles and I was asked once why I run a triple. I've been around bikes off and on for years BUT not bike culture much. I'm thinking the inquiry about my triple was grounded in, "real bikers don't need little chainrings, you whuse" elitism.
I really don't care if my handles don't match for this trip, the fact that I'm a 200 pounder with a trailer going 800 miles across Nevada and Utah should make it obvious to me.....keep the freeking triple. Doyle
Roadies are more often than not the worst people to ask for advice on touring. Rarely do they "get" it. Why spend the time / effort to change to 2 though, when you already have 3 and you're hitting some killer hills, loaded. It's of course doable, but perhaps not your most enjoyable option. Having the gears lets you go lower if you want to. No one's forcing you onto that small ring though.
Again, thanks to all of you for the discussion, this tour is already starting to be very fun! I just assembled my new Bob trailer and am loading it in the family room with my cargo. I have a doctor's scale and have weighed the trailer (me alone then me holding the trailer) @ 14 lbs. exactly. I've bought really light stuff (3 lb tent, 2 lb bag, etc.) and want to stay UNDER 50 lbs TOTAL trailer and ALL cargo, including water. Also, I took off the 50 psi tire and installed a 90 psi tire on the Bob (will use the 50psi for a spare).
SO, YOU TOURING EXPERTS, am I thinking clearly on all this? I so value your wisdom! Raydog
HardyWeinberg
03-07-10, 11:33 AM
OK, this thread is funny, sarcastic, cynical and most importantly....informative. Why am I considering going to a double? The complete Ultegra (double front, 10 rear) system I just acquired is black chrome and my existing Ultegra (triple front, 9 rear) is polished silver handles. I realize that cosmetics/bling is the least important issue in the world compared to function/efficiency.
Wow, a racing double, I was taking it for granted you meant a compact double which I figured could maybe get the job done w/ a 34t cog in the back. But I don't know if you can get a 10-spd cassette w/ a 34 in the back either. If this is an ultegra double/10 spd (27 or 28t large cog), I would be impressed with your fitness if you could use either component, never mind both, to pull a 45# trailer up any meaningful hill.
Wow, a racing double, I was taking it for granted you meant a compact double which I figured could maybe get the job done w/ a 34t cog in the back. But I don't know if you can get a 10-spd cassette w/ a 34 in the back either. If this is an ultegra double/10 spd (27 or 28t large cog), I would be impressed with your fitness if you could use either component, never mind both, to pull a 45# trailer up any meaningful hill.
Yeah, we'll never know if I "pack the gear" to do the double because the triple is staying on the bike! Does 45 lbs. sound about right for sleeping on the ground, no cooking stuff (restaurants, mini marts and Cliff bars are the food plan) cargo load?
10 Wheels
03-07-10, 12:09 PM
You might want take a trial camping trip one or two nights.
It is really the only way to test out everything you think you might need.
Less is Better.
You might want take a trial camping trip one or two nights.
It is really the only way to test out everything you think you might need.
Less is Better.
Roger that, as a matter of fact, as soon as the snow goes away (couple more weeks) I'm going to load her up and...from my house to a Sierras campground 76 miles away, Grover Hot Springs, do an overnight then back home again in morning. That way I can check out the rig on the road AND the camping equipment. If it all works out, it'll just be weekend centuries, mountain biking (just got a Cannondale Team Scalpel) Computrainer work....until departure day. I love this sport! My 3 motorcycles in the garage sure have taken a back seat recently. Raydog
vegenaise
03-07-10, 01:07 PM
Why use a compact double and not a fixie weak sauce? Man up mediocrity.
once did a century on a brakeless loaded fixie with a collapsed lung. no manning up needed over here.
edit- oh and this applies for dewaday's comment as well.
kayakdiver
03-07-10, 01:09 PM
once did a century on a loaded fixie with a collapsed lung. no manning up needed over here.
I bow to you super power ability.:lol:
dewaday
03-07-10, 03:01 PM
once did a century on a brakeless loaded fixie with a collapsed lung. no manning up needed over here.
u needed a lung, pfffft!
I once rode half way down Hwy1 on mushrooms, it was downhill all the way.
vegenaise
03-07-10, 06:41 PM
u needed a lung, pfffft!
yea, spontaneous pneumothorax can be a real *****.
I once rode half way down Hwy1 on mushrooms, it was downhill all the way.
were you afraid of crashing?
i was thinking the other day if it would be fun to ride while on mushrooms but every time i take mushrooms i get super exhausted and have to lay down and rest every 15 minutes. i don't think i could do it.
Bekologist
03-07-10, 10:21 PM
take bike with the loaded trailer and ride it up the largest hill near you on a shakedown.
-you can retrofit a Shimano Shadow derailleur and an 11-36 cassette if the road triple and 12-27 isn't enough.
It sounds like you're making your road gearing fit your touring needs....which is ok, but maybe the not the best approach. There's no reason to go from 9sp to 10sp, especially if you end up with a smaller large cog in the back. As for the compact double, it could be just fine depending of how fit you are, but standard doubles are wrong for most tourists as the top end will be seldom used and there's not enough bottom end. If you do want a double try something like a 42/26......combine it with an 11/34 cassette and you have a nice touring range. Of course the roadies will laugh at you tiny chain rings.
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