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-   -   Switching from Compact Double to Triple (http://www.bikeforums.net/fifty-plus-50/851579-switching-compact-double-triple.html)

rdtompki 10-10-12 08:21 AM

Switching from Compact Double to Triple
 
The die is cast, orders have been placed. I'm switching my Volagi FSA SL-K light Compact Crankset over to a triple. Found the same Crankset in a triple overseas as they are not sold in the US. Why do you ask? Well, it's not to get lower gears necessarily. I'm running an 11-32 cassette now and the 34-32 will get me up almost anything one time, like the 2500' climb 2 miles from my house. While on our tandem I'm resigned to the big jumps in our 11-32 (or 11-36), I find the jumps on my single interfere with the karma.

I'm going with a 12-27 cassette for regular, non-killer rides as the 30-27 will only be a few percentage points higher than what I had before and I really am going to like having the 16t cog. For longer and/or tougher stuff I figure a 36t cog will do the trick. If I can't get up a hill in 30-36 then I have no business riding that hill.

My 84 Miyata 912 had a triple and I don't recall way back then wishing I had something different. My son still uses that bike as his beater, but I'm getting it back soon. He's made some changes, but hasn't changed out the crankset thank goodness so I'll have two triples in my stable, N+1 so to speak.

My biggest concern is that with a triple I won't be allowed to post in the 41, but I'm figuring I'll still be ok here and in the C/A forum.

Barrettscv 10-10-12 09:37 AM

Concerning the 41: http://www.bikeforums.net/showthread...upport-Group)?

Another option to increase the range of a triple, while keeping the 16t cog on the cassette, is to add a 26t granny gear to a 74 BCD crankset. Just be sure to size the chain again, you might need to remove a few links before using the small-small combination.

http://i289.photobucket.com/albums/l...t/CG2011-1.jpg

volosong 10-10-12 09:41 AM

You're safe here.

I'm just about to go the other way with one of my triples. I've experienced on my bike with a 12-30 and compact crank that I can get up just about anything around here. So, I'm switching my "go fast" bike from a triple to a compact double. I'll leave one bike with a triple for those really steep hills, (such as the ski lifts at Baldy).

stapfam 10-10-12 10:11 AM

Two bikes with compacts and 34/27 gearing and a triple with 50/39/30 and 12/25.

With the Tiagra 12/30t cassette (which I have on one set of wheels and when using the Compact crank) I can climb anything as slow as I like. The 27 does take a bit more effort but is OK. Reason I put a triple on one bike was for those long hilly rides where I just want that little bit "Extra" on the gearing. Initially I used a 12/27 and found the wider spacing on the 3 higher gears annoying and that is why I went to the 25. In theory I should find the same problem with the 12/30 on the compacts but I don't. When you need those lower gears- you need them.

And lower gears- The Tandem has 48/36/24 chainrings with a 12/32 cassette and we need all those gears. Did try a 12/34 cassette but we kept bending the 34 with the power we put out.

rdtompki 10-10-12 10:22 AM

Quote:

Originally Posted by Barrettscv (Post 14826217)
Concerning the 41: http://www.bikeforums.net/showthread...upport-Group)?

Another option to increase the range of a triple, while keeping the 16t cog on the cassette, is to add a 26t granny gear to a 74 BCD crankset. Just be sure to size the chain again, you might need to remove a few links before using the small-small combination.

http://i289.photobucket.com/albums/l.../IMG_08871.jpg

That thread you reference really made me feel all warm and fuzzy, but may have been missed by the 41 censors;) The FSA crankset is 74 BCD so I do have the option of going smaller than 30t, but for the time being I'm sticking with stock since the 52-39-30 is as big a span (22t) as the Ultegra triple FD is designed to handle; I'm guessing it might handle a 28t small chainring or so without going to a 50t.

You bring up a good point about chain take-up. I'm currently running a Rival RD, but am probably at the very limit; I'll have to pop on my spare SRAM X.9. I'm also hoping the FSA triple shifts reasonably. My shifters are Campy 10-spd for I've got plenty of resolution, 10 clicks I believe, enough even to shift the quad chainrings on our daVinci. (NOTE: the Rival mid-cage will handle the (52-30)+(27-12), but at 37t chain wrap we're at the limit)

I'm not too concerned about large jumps in the back if I'm doing a lot of climbing so 11-32 or more will be fine; I rode one 100K with 6000' and all I was looking for in the flats was survival, no karma required.

In these parts, while there are a few easy centuries, a century with 5000' of climbing would be considered easy, 7000'+ is common:cry:

Retro Grouch 10-10-12 11:14 AM

Quote:

Originally Posted by rdtompki (Post 14825928)
My biggest concern is that with a triple I won't be allowed to post in the 41.

Oh my! Surely there must be a few riders who are smart enough to shift a triple yet still want to post in the 41.

lhbernhardt 10-10-12 11:23 AM

Yeah, but they don't make Di2 for triples (yet). Otherwise I'd be tempted to get it for my tandem.

What I found on my last double century (Knoxville), though, is that I bog down completely on a 15-18% grade at 5 kmh on my 44x17 fixed gear. So when I get off the bike and start walking, I find I'm doing 4 to 5 kmh anyway. Always wondered why anyone would use a triple to ride at slower than walking speed; I guess you can spin up the tiny gear and still maintain a reasonable (faster than walking) speed on the steepest climbs.

Luis

rdtompki 10-10-12 11:32 AM

Quote:

Originally Posted by lhbernhardt (Post 14826722)
Yeah, but they don't make Di2 for triples (yet). Otherwise I'd be tempted to get it for my tandem.

What I found on my last double century (Knoxville), though, is that I bog down completely on a 15-18% grade at 5 kmh on my 44x17 fixed gear. So when I get off the bike and start walking, I find I'm doing 4 to 5 kmh anyway. Always wondered why anyone would use a triple to ride at slower than walking speed; I guess you can spin up the tiny gear and still maintain a reasonable (faster than walking) speed on the steepest climbs.

Luis

Agree completely on the super low gears, but on our tandem my wife's power to weight is much lower than mine so when we hit 12%+ we're slogging in a 24-36. I can actually walk the tandem uphill that fast, but my wife hates to walk. I made the mistake of muttering under my breath once that we should consider walking - bad move. Riding the tandem has made me much stronger (good news), but because of my body type, even considering my age, I've got a lot of muscle in my legs. That's why I still weight near 200; that's my story and I'm sticking to it.

stapfam 10-10-12 12:31 PM

Can tell you now that I do not walk a bike uphill. I don't care how slow I am- I will not walk. Those bikes get very heavy when being pushed and thanks to my Knees-I would not get very far if I had to.

Can remember a ride on the Tandem where we were overtaken by riders walking their bikes up a certain hill. We got to the top with legs still working and just took off. Those that had walked took a little rest before riding again. Mind you- it was on the gnarliest bit of trail that had the steepest slope on it and I looked at the trail and providing we could balance and not fall-I was not going to push that 55lb bike anywhere.

Drew Eckhardt 10-10-12 12:38 PM

Quote:

Originally Posted by rdtompki (Post 14825928)
The die is cast, orders have been placed. I'm switching my Volagi FSA SL-K light Compact Crankset over to a triple. Found the same Crankset in a triple overseas as they are not sold in the US. Why do you ask? Well, it's not to get lower gears necessarily. I'm running an 11-32 cassette now and the 34-32 will get me up almost anything one time, like the 2500' climb 2 miles from my house. While on our tandem I'm resigned to the big jumps in our 11-32 (or 11-36), I find the jumps on my single interfere with the karma.

I'm going with a 12-27 cassette for regular, non-killer rides as the 30-27 will only be a few percentage points higher than what I had before and I really am going to like having the 16t cog. For longer and/or tougher stuff I figure a 36t cog will do the trick. If I can't get up a hill in 30-36 then I have no business riding that hill.

My 84 Miyata 912 had a triple and I don't recall way back then wishing I had something different. My son still uses that bike as his beater, but I'm getting it back soon. He's made some changes, but hasn't changed out the crankset thank goodness so I'll have two triples in my stable, N+1 so to speak.

My biggest concern is that with a triple I won't be allowed to post in the 41, but I'm figuring I'll still be ok here and in the C/A forum.

FWIW you can run a 13 starting cog and net an 18 cog too (13-14-15-16-17-18-19-21-23-26) and/or run a ring smaller than 30 (26x23 is the same gear as 30x27 and allows 12-13-14-15-16-17-18-19-21-23, and 26x26 or 27 is lower than 34x32).

I've mostly run a triple since noting in the 8 speed era that 50-40-30x13-14-15-16-17-18-19-21 meant a 7-speed corncob for plains rides and a low like 42x28 for mountains without wheel or cog changes.

icyclist 10-10-12 01:00 PM

I ride enough that I can get up steep grades (i.e. grades as steep or steeper than 20%) on a compact or on my standard. I'm slower than I used to be, however I seem as strong or stronger as ever.

rdtompki - where is your two mile, 2500 ft climb? I might put my triple back on one of my bikes for that. :)

rdtompki 10-10-12 01:14 PM

Quote:

Originally Posted by icyclist (Post 14827196)
I ride enough that I can get up steep grades (i.e. grades as steep or steeper than 20%) on a compact or on my standard. I'm slower than I used to be, however I seem as strong or stronger as ever.

rdtompki - where is your two mile, 2500 ft climb? I might put my triple back on one of my bikes for that. :)

The climb is 2 miles from my house. That actually climbing portion is about 8 miles, below:
http://ridewithgps.com/routes/165087/elevation_profile
The unfortunate part of this out/back ride is that the road is in really bad shape so downhill requires a lot of concentration and a lot of hard braking.

The hardest nearby climb is actually shorter, but has a 2 mile stretch that just barely nudges below 10% at one point, 99% is between 10 and 12%.

At my size heat is a big, big deal; this is exacerbated on the tandem where our speeds get quite low.

icyclist 10-10-12 01:35 PM

"44x17 fixed gear. So when I get off the bike and start walking"

Walking?!?To each his own. ;)

"I guess you can spin up the tiny gear and still maintain a reasonable (faster than walking) speed on the steepest climbs."

Not necessarily. In your case, you're turning the cranks 15 times a minute on your fixie to maintain your 5km speed. I can imagine that it would be a challenge just to stay upright at that very slow speed (about 3mph for the metric-challenged).

With a 30t triple and 28 cog at 5km, you'd still be spinning very slowly, under 40 rpms. And at such a slow speed, again the ability to balance would be an issue.

So whether or not someone can walk as fast or faster than a cyclist up a steep hill depends more than on just the cyclist's gearing. It depends on the steepness of the hill as well as the fitness of the rider.

icyclist 10-10-12 01:39 PM

Quote:

Originally Posted by rdtompki (Post 14827248)
The climb is 2 miles from my house. That actually climbing portion is about 8 miles"

I missed your original comment. Still, a good climb, especially on a tandem.

billydonn 10-10-12 02:51 PM

You are wise to go triple, IMO. :thumb: The Ultegra FD will make the shifts from 52 to 26 just fine, BUT it would be wise to install a chain catcher if you add a 26 tooth granny.

I agree with the "anti-walker" sentiment. I won't do it either... but that doesn't mean I won't stop and rest if I have to.:)

Ludkeh 10-10-12 03:05 PM

I've got a Specialized Roubaix triple that came with the 50/39/30 front gears. I was struggling on the hills here in Central New York. I switched out the 30 tooth gear for a 28 tooth gear that I had pulled off my old triple steel bike that I still had. That one switch made a remarkable difference!! The slightly lower gearing lets me slowly grind up most steep hills at a round 6 mph. I just sit back on the saddle and grind away! :)

rdtompki 10-10-12 04:20 PM

Quote:

Originally Posted by billydonn (Post 14827655)
You are wise to go triple, IMO. :thumb: The Ultegra FD will make the shifts from 52 to 26 just fine, BUT it would be wise to install a chain catcher if you add a 26 tooth granny.

I agree with the "anti-walker" sentiment. I won't do it either... but that doesn't mean I won't stop and rest if I have to.:)

I already have a chain catcher (CF frame). Wouldn't leave home without it!

I am anti-walker, but try to explain to your wife/stoker that you would rather ride the tandem up the hill solo while she walks; you just don't go there. What our very low tandem gearing does is let us get up grades that would otherwise require walking; I don't mean 16% switchbacks, but longer stretches of 15-16%. We are nearing 136 y/o so I think we're hanging in there:)

cccorlew 10-10-12 10:27 PM

Quote:

Originally Posted by Ludkeh (Post 14827717)
I've got a Specialized Roubaix triple that came with the 50/39/30 front gears. I was struggling on the hills here in Central New York. I switched out the 30 tooth gear for a 28 tooth gear that I had pulled off my old triple steel bike that I still had.....

I've been told that with the 6700 Ultegra that can't be done. Which is a bummer because I'd love it.
My triple is 52-39-30, which is just stupid. Like someone who want's a triple needs an 11 tooth cog.

Love the way it shifts, but I'd really like it if it was like my Velo Orange on my commuter, 24, 36, 48.

I'll do double centuries, but I sure like low gears with a lot of choices.

Good luck with your project!

billydonn 10-11-12 12:24 AM

Curtis is right. New Ultegra triple cranks will not take a smaller inner chainring.

NOS88 10-11-12 06:24 AM

One of the true joys of cycling for some of us is just this sort of thing; we get to play around with things wondering if or how they might work. I'm enjoying this thread.

My father was an avid fisherman all of his life. He tied his own flies, built his own fishing rods, made over 1,000 fishing lures, and had more reels than a person could ever use (each of which he took apart on numerous occasions to clean and lube). Even today, he puts new guides on and re-wraps the threads on fishing rods for friends and neighbors. When I first got into cycling, he just shook his head, not understanding it at all. It wasn't until he was visiting one day and saw that I had three bikes apart swapping parts, re-wrapping handlebars, putting in new grease, and generally just enjoying the whole process that he came around. I remember with his eyes lit up, he said, "Bradley, this bicycle thing can be a tinkerer's dream."

Retro Grouch 10-11-12 07:19 AM

Quote:

Originally Posted by Barrettscv (Post 14826217)
Another option to increase the range of a triple, while keeping the 16t cog on the cassette, is to add a 26t granny gear to a 74 BCD crankset. Just be sure to size the chain again, you might need to remove a few links before using the small-small combination.

I think that's bad advice.

A chain that's too short to safely cover the big/big combination can cause a LOT of damage to your bike in the blink of an eyelash. One that's too long to cover the little/little will only make annoying noise.

Besides, I have never used my granny chainring with any but my largest 2 or 3 rear cogs. I can easily picture myself accidentally shifting into the big/big, but I can't imagine ever accidentally shifting into the little/little.

rdtompki 10-11-12 07:47 AM

Regarding going lower than 30t up front - the 30t-27t combo is plenty low enough for my workout 30-40 mile rides with at most one bad climb. Something longer with more climbing I'd put on an 11-36 in a heartbeat (with properly sized chain) and be pleased to survive, karma aside. There are two organized rides that are too tough for us on the tandem, even the 100K version, and I really want to ride these on my single which is where the 36t cog would come in.

As for tinkering, I don't now which is more/less expensive, N+1 or tinkering on one's only ride. When I get my hands back on my old Miyata I'll try to tinker it back to near original.

big john 10-11-12 07:55 AM

Quote:

Originally Posted by cccorlew (Post 14829072)
I've been told that with the 6700 Ultegra that can't be done. Which is a bummer because I'd love it.
My triple is 52-39-30, which is just stupid. Like someone who want's a triple needs an 11 tooth cog.

Why do you say it's stupid? On my Gunnar I have a 52-39-30 triple with a 11-25 cassette. A gear for almost anything, including the 52x11 for chasing those skinny climbers on the descents. I put an 11-30 cassette on it for a trip into the Eastern Sierra mountains and the 30x30 helped a lot.
Lately, I've been riding the other bike which has a 50-34 with a 13-29. Low enough for climbing but I really miss the big gears on some rides. Gonna have to change that cassette.

pexio 10-11-12 08:25 AM

Quote:

Originally Posted by billydonn (Post 14829219)
Curtis is right. New Ultegra triple cranks will not take a smaller inner chainring.

Actually you can put a smaller inner chainring on new Ultegra triple cranks but you will need a new middle ring first. As you know, with the 6703 Ultegra triple, Shimano adopted the older Dura Ace triple design of mounting the inner ring directly onto the middle ring using a proprietary 92mm BCD for which only 30t rings are available. By replacing the stock Ultegra middle ring with a Specialites TA Alize K, you can mount a granny ring as low as 24t. The Alize K uses the industry-standard 74mm BCD for the granny - not the Shimano-only 92mm. It's not a cheap ring, but it is a TA after all. ;) I got mine from Peter White Cycles - see this page. Here's is my Alize K setup:

http://farm9.staticflickr.com/8054/8...5ed95a7f_c.jpg

This is a DA FC-7703 crank (same 130/92 BCD as Ultegra) with the stock 53t big ring, a 39t Alize K and a 26t granny. With a 10 speed 12-28 cassette, I have a nice wide gear range (which my knees appreciate riding in the Berkshires here in western MA), fewer front shifts, and tight gear spacing (one tooth jumps from 12t to 17t). Triples are great!

rdtompki 10-11-12 08:45 AM

Quote:

Originally Posted by pexio (Post 14829902)
Actually you can put a smaller inner chainring on new Ultegra triple cranks but you will need a new middle ring first. As you know, with the 6703 Ultegra triple, Shimano adopted the older Dura Ace triple design of mounting the inner ring directly onto the middle ring using a proprietary 92mm BCD for which only 30t rings are available. By replacing the stock Ultegra middle ring with a Specialites TA Alize K, you can mount a granny ring as low as 24t. The Alize K uses the industry-standard 74mm BCD for the granny - not the Shimano-only 92mm. It's not a cheap ring, but it is a TA after all. ;) I got mine from Peter White Cycles - see this page. Here's is my Alize K setup:

http://farm9.staticflickr.com/8054/8...5ed95a7f_c.jpg

This is a DA FC-7703 crank (same 130/92 BCD as Ultegra) with the stock 53t big ring, a 39t Alize K and a 26t granny. With a 10 speed 12-28 cassette, I have a nice wide gear range (which my knees appreciate riding in the Berkshires here in western MA), fewer front shifts, and tight gear spacing (one tooth jumps from 12t to 17t). Triples are great!

Sweet looking setup!. I'll be interested to see how well the FSA triple shifts. I don't have indexed shifting up front so the shift efficiency has a big operator component.


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