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Discussion Starter · #1 ·
I have a 105 triple setup on my OCR1 and would like to convert to a double. What do I all need to change. I was hoping to find someone that has a double and wants to switch to a triple. While I'm at it, what is a "compact" crankset all the kids are talking about.
 

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NeoRetroGrouch
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jayebird said:
I have a 105 triple setup on my OCR1 and would like to convert to a double. What do I all need to change. I was hoping to find someone that has a double and wants to switch to a triple. While I'm at it, what is a "compact" crankset all the kids are talking about.
Asuming 105-9 - Officially you need a crankset, bottom bracket and front derailleur to switch to a double. Some report success using the same FD. Probably new cables and housing as well as shortening the chain.

I'll let others chime in on the compact.

TF
 

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Some also recommend a short cage rear derailleur for crisper shifting, although others claim this is not necessary.
Re- Compact- Most compacts include chainrings of 50/34 or 50/36 (vs 53/39 for standard double). Typical triple is 52/42/30 or similar. Remember that your final drive ratios (gear-inches) will also depend upon your rear cassette.

Before changing to a double, honestly ask yourself how often you use your smallest chainring AND what gearing you use for most of your riding. If you are almost always in the middle ring (i.e. only shifting rear gears), changing to a compact may frustrate you if you find you now must change both FD and RD to find the right gearing. Also- calculate exactly what smallest gear ratios you would loose going to a double. Typically a std double would be the equivalent of losing the lowest 2-3 gears vs a triple (i.e. small ring with largest 2 or 3 sprockets), while a compact would be losing the lowest gear (i.e. small/large). The compact would also loose a bit on the top end (i.e. spinning at 30-31mph+).

FWIW- I ride a triple and am trying to decide if I really want to change. I ride about 65% in the middle ring, 30% big ring, and 5% small (only during really hilly rides). As I see it, benefits to the compact would include lower weight and crisper front shifting. Downside includes the loss of a bit of the lowest and highest gearing, perhaps more frequent front shifts, and (of course) the $$$. As far as appearances go- I would rather ride my triple up the steepest hills rather than walk a std double.

Good luck whatever you decide.
 

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Oldteen said:
Some also recommend a short cage rear derailleur for crisper shifting, although others claim this is not necessary.
Re- Compact- Most compacts include chainrings of 50/34 or 50/36 (vs 53/39 for standard double). Typical triple is 52/42/30 or similar. Remember that your final drive ratios (gear-inches) will also depend upon your rear cassette.

Before changing to a double, honestly ask yourself how often you use your smallest chainring AND what gearing you use for most of your riding. If you are almost always in the middle ring (i.e. only shifting rear gears), changing to a compact may frustrate you if you find you now must change both FD and RD to find the right gearing. Also- calculate exactly what smallest gear ratios you would loose going to a double. Typically a std double would be the equivalent of losing the lowest 2-3 gears vs a triple (i.e. small ring with largest 2 or 3 sprockets), while a compact would be losing the lowest gear (i.e. small/large). The compact would also loose a bit on the top end (i.e. spinning at 30-31mph+).

FWIW- I ride a triple and am trying to decide if I really want to change. I ride about 65% in the middle ring, 30% big ring, and 5% small (only during really hilly rides). As I see it, benefits to the compact would include lower weight and crisper front shifting. Downside includes the loss of a bit of the lowest and highest gearing, perhaps more frequent front shifts, and (of course) the $$$. As far as appearances go- I would rather ride my triple up the steepest hills rather than walk a std double.

Good luck whatever you decide.
Unless you are racing and really need the shifts to be fast and super-crisp then stay with the triple. The ability to drop into a granny gear for steeps is a nice thing. I have a double now and always envy those with a triple when the going gets steep. Don't race or ride near as much as I did before so fast, precise shifting is kind of a moot point.
 

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I have one bike with a triple and another with a 50/36 compact double. The compact double is all Campagnolo Record - as good as it gets. It doesn't shift any better than my triple (also Campagnolo.) Also I don't go any faster on the bike with the compact double even though it is 5 lbs. lighter.

How much weight will you save with the switch? I don't know but it is trivial. You can heft a 30 tooth chain ring and see for yourself.

The only thing that changes with the move you want to make is that you will have a narrower range of gearing. That's it. In other words there is a downside and no upside. I'm not kidding. Leave it alone.
 

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Good points & experiences in this triple vs double issue.
There is also the 'Fred-avoidance factor' with the "better dead than caught riding a triple" crowd.
Part of my issue is indeed weight, and I do not road race (just club-level MTB). My current triple is a boat anchor (literally 1.3kg w/square BB), so if I'm changing it out anyway why not at least consider a compact double? Even a lower-end FSA Gossamer compact w/ext BB would shave around 1 lb of (rotating) weight off the bike. Based on my experience with dropping about that much weight with a newer wheelset, I am guessing that crankset change would be significant to me on a faster-paced metric (or longer) ride. I fully agree that saving 50-100g more by going to a carbon crankset would be a waste.
OTOH-favoring the triple- I must confess to having used my granny gear a time or two on the steepest of the hills I've encountered on regional rides. Would I have made it up those climbs with a double???
 

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I have a triple right now and i rarely if ever use my granny gear. my father also has a triple and he never uses his inner gear either. we live in a pretty hilly area, so i guess switching to double depends on your condition. I would see if I could find a kind friend with a double to see how you like it. I'll probably switch to a double soon.
 

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Oldteen said:
Good points & experiences in this triple vs double issue.
There is also the 'Fred-avoidance factor' with the "better dead than caught riding a triple" crowd.
Part of my issue is indeed weight, and I do not road race (just club-level MTB). My current triple is a boat anchor (literally 1.3kg w/square BB), so if I'm changing it out anyway why not at least consider a compact double? Even a lower-end FSA Gossamer compact w/ext BB would shave around 1 lb of (rotating) weight off the bike. Based on my experience with dropping about that much weight with a newer wheelset, I am guessing that crankset change would be significant to me on a faster-paced metric (or longer) ride. I fully agree that saving 50-100g more by going to a carbon crankset would be a waste.
OTOH-favoring the triple- I must confess to having used my granny gear a time or two on the steepest of the hills I've encountered on regional rides. Would I have made it up those climbs with a double???
If you think riding a triple is a slam against your manhood, then I can't help you with that. It is an immature point of view. You can't save anywhere near a pound. Most cranksets don't even weigh a pound. What you will save is the weight of a 30 tooth chainring which next to nothing. If you think a few grams is going to make any difference in your riding then you are kidding yourself. I've been through the whole weight weenie thing and it is a hobby, not a way to improve riding performance. I once bought a Stronglight Pulsion crankset. I hated it. Complete waste of money. I'd rather have a triple. Do what you're going to do. Just realize it won't benefit you except emotionally. Sorry to be so agressive but I hate to see newcomers to the sport fall prey to this nonsense. Take care.
 

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Discussion Starter · #13 ·
I guess I am looking at it from a fashion standpoint. I think I will stay with the triple. My knees want me to anyway. I do not race, so what is the point? I guess I think double just looks better... then again I did see a cool ultega triple that was sexy(er) than my 105. Thanks for all the advise.
 

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smaller inside ring...?

if your knees are hurting and you don't want to change the entire
bb/crank, you can still get down as low as a 38t; that's what i did -
53/39 -13/23 down to 50/38 - 12/25, didn't have to change much,
didn't have to take off the crank, now i've got a low enough gear
for some of the decent hills near me - i don't feel like i'm gonna die
when i get to the top ;-)


jayebird said:
I guess I am looking at it from a fashion standpoint. I think I will stay with the triple. My knees want me to anyway. I do not race, so what is the point? I guess I think double just looks better... then again I did see a cool ultega triple that was sexy(er) than my 105. Thanks for all the advise.
 

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fmw said:
If you think riding a triple is a slam against your manhood, then I can't help you with that. It is an immature point of view. You can't save anywhere near a pound. Most cranksets don't even weigh a pound. What you will save is the weight of a 30 tooth chainring which next to nothing. If you think a few grams is going to make any difference in your riding then you are kidding yourself. I've been through the whole weight weenie thing and it is a hobby, not a way to improve riding performance. I once bought a Stronglight Pulsion crankset. I hated it. Complete waste of money. I'd rather have a triple. Do what you're going to do. Just realize it won't benefit you except emotionally. Sorry to be so agressive but I hate to see newcomers to the sport fall prey to this nonsense. Take care.
You're not being aggressive. As I said, I appreciate your input.

Regarding weight, I was considering both crank & BB together, since Triple to Double conversion requires a shorter BB. Here's my figures (from manufacturer websites):

Truvativ Touro Triple (Sq BB) OEM 975g (a heavy triple)
Shimano Sq/taper BB 251g

Total OEM Triple 1226g

FSA Gossamer Compact 890g (a relatively heavy compact dbl)
(w Megaexo BB)

Difference 336g or 0.74 lbs

Not quite 1 lb, so I stand corrected. My only thought here is that a replacement crankset could be a source of relatively significant weight loss. I'm not a 50g here and there weight weenie. For example, I did not go with the lightest replacement wheelset (32-spoke 3X Ult/OP's).

I do not agree with the 'manhood' issue either, just admitting that it exists in some quarters. What is so macho about having a double but having to bail and walk it up your toughest hills (as I witnessed during my last metric)??? I rarely use my small ring, but I have indeed RIDDEN my granny gear (small ring/large cog) to clear the top of some extended >10% grade climbs presenting 40-50mi into a hilly ride.
FWIW- I am keeping my triple (at least for now) for just those rare situations.
 

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Just visited the Shimano website.

I owe fmw an apology. His weight analysis re- triple vs double is spot on.

For Ultegra crankets (inc. BB), triple is 922g while the double is 839g.
The difference is a trivial 83g.

My weight prior analysis illustrated nothing more than the fact that I have a HEAVY triple/BB combo, not that triples per se are that much heavier than doubles.

Re- weight vs performance
I ran power models on analytic cycling and a shareware cycling power calculator (gearhead powercal). At 18mph on level ground, the addition of 1 full KILO of weight increases power requirement by only a fraction of a watt (less than 0.3% of total power). Even on a grade of 4% the added kilo still requires less than 1% additional power. I could not run the analysis for an added 0.083 kg (the above triple vs double difference), but since this is a roughly linear relationship I would predict the added power requirement for an additional 83g to be approx 0.024%.
To quote fmw, to worry about such weight differences is "a hobby, not a way to increase riding performance".
 

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Thanks for the post, Oldteen. I appreciate it. Much of the information you read on this forum and others is nonsense and I get attacked pretty vigorously when I confront something that is a popular urban legend, I take a lot of poorly aimed shots about it. I quit posting once because of it.

The problem with the triple to double issue is that people think that other riders will consider them to be weak if they use a triple. I know one fellow who has a 13/29 cassette so he can avoid using one. Apparently there are a lot of people with low self esteem and confidence. My personal opinion is that every rider (except for very strong racers) should use a triple. The difference in Q is trivial. The weight difference is meaningless, as you point out. The shifting performance is the same - at least it is with the Campy triples with which I have experience.

And the advantage is a wider range of gears. Why is that important? Unless I am a strong racer - and I, for one, am not - it is more efficient and more fun for me to spin up a hill at 80 or 90 RPM than it is to stand up, grimace and climb painfully so that nobody will think I can't do it with 39 chain ring. I can do it with a 39 chain ring. I just don't if I don't have to. Also triples generally require less shifting on the front derailleur. Fewer shifts is a good thing, I think.

So the reason triples have fallen from favor is simply ego. There is no performance reason at all for it. If your name is Basso or Ullrich or that of another pro tour racer, you only need a triple or similar gearing for some of the most extreme climbs on the pro tour. The rest of us don't need one either but it makes riding more efficient and more fun.

To drive home the point about weight. I have two road bikes that I ride regularly. The difference in weight between them is not 100 grams or 1/2 lb. The difference between them is 5 lbs. My riding performance is about the same on both bikes. The 5 lb. difference is meaningless for me since my name isn't Basso or Ullrich. So for riders like me, worrying about weight is hobby and nothing more - a fun but expensive hobby.
 
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