# Ultegra 6700 Compact to Standard Change



## jcgill (Jul 20, 2010)

Hello, i have a 2010 Trek Madone 5.1 (OCLV Carbon with Ultegra 6700 components). It came equipped with a compact crank, and i live in NW Indiana and it is mostly all flats around here, so i would like to change to a standard 53/39 crankset.

What Parts do i need to change to accomidate the standard crank?

-I know i need to move the Front Derailuer up, to compensate for the larger diameter chainrings.
-Will the same Front and Rear Derailuers still work with a standard crank or will i need different cage length derailuers???
-I think i read that Ultegra 6700 chainring sizes cannot be changed witout changing the whole crank, is this true???

I think i need to buy: The standard crank, corrisponding cassette, longer chain. Does this sound right?
What else do i need to do/know for the swap???

Thanks in advance,
Jon


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## wim (Feb 28, 2005)

Correct, you need a whole new crank if you want to go standard. Chainrings for a compact crank do not fit a standard crank because the so-called bolt circle diameters (BCD) are different. Derailleurs will work fine. The chain might have to be lengthened, but it depends on how long or short it was cut originally.

But really, what you want to do makes little sense, especially in view of the expense involved. Around the middle of the cassette, a three-tooth difference in front (like 50 to 53) equals only a one-tooth difference in the rear (like 15 to 14). So to get the effect of a 53, just make one shift in the rear with your 50. I doubt if you're spinnig out your 50 x 11 on the flat. The differences between compact and standard cranks are much smaller than the ferocity of the compact vs. standard debate would have you believe.

Not sure what you mean by "corresponding cassette."


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## C-40 (Feb 4, 2004)

*thoughts...*

I rode mostly in the mountains for about 7 years, but moved to flatter ground, just last year. I still use my compact crank with an 11-25 (11 speed), but almost never have to use the little ring, since the 50/23 is a useable combination. You shouldn't be spinning out with a 50/11. If you change to a standard crank, you'd probably never use the 53/11, so almost nothing is to be gained.

About the only advantage to the standard crank is one less cog-shift after a chainring shift, since the percentage difference between the chainrings is smaller. You could do the same thing with a 50/36 compact.


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## Kontact (Apr 1, 2011)

wim said:


> Correct, you need a whole new crank if you want to go standard. Chainrings for a compact crank do not fit a standard crank because the so-called bolt circle diameters (BCD) are different. Derailleurs will work fine. The chain might have to be lengthened, but it depends on how long or short it was cut originally.
> 
> But really, what you want to do makes little sense, especially in view of the expense involved. Around the middle of the cassette, a three-tooth difference in front (like 50 to 53) equals only a one-tooth difference in the rear (like 15 to 14). So to get the effect of a 53, just make one shift in the rear with your 50. I doubt if you're spinnig out your 50 x 11 on the flat. The differences between compact and standard cranks are much smaller than the ferocity of the compact vs. standard debate would have you believe.
> 
> Not sure what you mean by "corresponding cassette."


I don't follow your post. One has been able to get "standard" 53/39 chainrings with a 110 BCD to mount on "compact" cranks for decades.

People generally don't because 130 cranks are stiffer and it is usually a waste of money buying just chainrings, but it certainly can be done. For lighter riders it wouldn't matter.




I do agree that there aren't many reasons to switch back to traditional - at least gearing reasons. But if a dude prefers something, that's up to him.


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## wim (Feb 28, 2005)

Kontact said:


> One has been able to get "standard" 53/39 chainrings with a 110 BCD to mount on "compact" cranks for decades.


Absolutely, and I did just that many years ago—long before 110 BCD was known as "compact."

As an aside: to "not get my post" because of my omission is not giving yourself enough credit for plain old common sense.


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## jcgill (Jul 20, 2010)

Thanks wim, the reason i was considering the switch is because this summer i got alot more involved in cycling, doing group rides etc. and i have been riding my Cannondale CAAD10-3 Ultegra which is standard. 
I have been using my Madone for solo rides, and have been nervous to take the madone on a group ride, for fear of being left behind with the compact crank.

Let me see if i am understanding this correctly:
So you are saying with my compact, i just need to be in the next smaller gear vs. the guy next to me with a standard crank and if our cadences are similar we will travel the same speed??? if i am 50x13 and hes 53x14 i will still hang with him???


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## Kontact (Apr 1, 2011)

jcgill said:


> Thanks wim, the reason i was considering the switch is because this summer i got alot more involved in cycling, doing group rides etc. and i have been riding my Cannondale CAAD10-3 Ultegra which is standard.
> I have been using my Madone for solo rides, and have been nervous to take the madone on a group ride, for fear of being left behind with the compact crank.
> 
> Let me see if i am understanding this correctly:
> So you are saying with my compact, i just need to be in the next smaller gear vs. the guy next to me with a standard crank and if our cadences are similar we will travel the same speed??? if i am 50x13 and hes 53x14 i will still hang with him???


The typical high gear on a traditional is a 53x12. The typical compact high gear is a 50x11. The 50x11 is actually a slightly higher gear and is in the exact same position as the tradistional high gear.

Compact gearing is not geared lower overall. They just produce a broader range than traditional. While the compact crank is somewhat lower, it is usually paired with a higher geared cassette, like in the above example.


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## wim (Feb 28, 2005)

jcgill said:


> if i am 50x13 and hes 53x14 i will still hang with him???


Correct, you're basically pushing the same gear ratio, with you actually on the slightly bigger gear (50 x 13 = 102 gear inches; 53 x 14 = 100 gear inches). Forget the 2-gear inch difference, it's hardly worth mentioning. So you can hang with him if everything else is the same, of course. If he's fitter than you are, no. But you knew that. 

One thing you should keep in mind: gear size is not proportional to achievable speed! There are people out there who would drop you in a heartbeat while turning a _smaller_ gear (like a 48 x 15) than you are.

/w


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## jcgill (Jul 20, 2010)

wim said:


> Correct, you're basically pushing the same gear ratio, with you actually on the slightly bigger gear (50 x 13 = 102 gear inches; 53 x 14 = 100 gear inches). Forget the 2-gear inch difference, it's hardly worth mentioning. So you can hang with him if everything else is the same, of course. If he's fitter than you are, no. But you knew that.
> 
> One thing you should keep in mind: gear size is not proportional to speed! There are people out there who would drop you in a heartbeat while turning a _smaller_ gear (like a 48 x 15) than you are.


Ok that makes sense now. My hypothetical example was considering both our cadences were exactally the same, and all other conditions were the same.

So that being said, i guess there is no reason to spend $400+ on the switch when i can just shift to 1 gear smaller in the rear on my compact!


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## wim (Feb 28, 2005)

jcgill said:


> So that being said, i guess there is no reason to spend $400+ on the switch when i can just shift to 1 gear smaller in the rear on my compact!


I would concur with that. The other option is to stay in the same cog than your friend, but train yourself to increase cadence slightly above his—about 5 rpm more with both of you in a 14. This option will pay benefits towards the end of a long ride.


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## MickeH (Aug 10, 2011)

My problem with compact cranks is actually the smaller chain ring. To me a 34 is useless because the hills around here are to small for it. I tend to stay on the bigger chain ring too much. A 50-39 would probably be better than 50-34 and I think that might be the case for anyone outside of the alps and similar areas. So I think I will be moving to a 53-39.


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## singlespeedbuss (Aug 6, 2009)

Try someone else`s bike before forking out the dough or rent something from a LBS. You may find you really don`t need to spend the money. I have standard gearing and never need 53x11. Better to spin a smaller gear than trying to grind a big gear. Your knees will thank you.


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## Drew Eckhardt (Nov 11, 2009)

MickeH said:


> My problem with compact cranks is actually the smaller chain ring. To me a 34 is useless because the hills around here are to small for it.


If you're spinning over everything in your 50x19 (out of 11-12-13-14-15-16-17-18-19-21) or 50x21 (with 12-13-14-15-16-17-18-19-21-23) you might want a bigger small ring you can use for cruising with fewer double shifts.

If you're not running one of those cassettes and using the pie-plate sized cogs bike companies ship to placate people who'd otherwise want triples like the 11-12-13-14-15-17-19-22-25-28 Trek used on the OP's Madone 5.1 you'd do well to switch.

Where you used to spin over small bumps with 50x25 you'll be making good use of your 34x17 (with a lot less chain noise); and where the road isn't so bumpy you may really enjoy the 50x18 (20-22 MPH gear) and 50x16 (22-25).



> I tend to stay on the bigger chain ring too much. A 50-39 would probably be better than 50-34 and I think that might be the case for anyone outside of the alps and similar areas. So I think I will be moving to a 53-39.


The 28 cog which lets bike companies sell one SKU to alp-riding/less-fit/larger riders and flat-riding/more-fit/smaller riders was more than ample to get fit riders over the Rocky Mountains when we ran 42 small rings. 

If you fit into the later category you'd do well with a big cog no larger than a 23 with 34x23 being a slightly easier gear than 42x28.


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## MickeH (Aug 10, 2011)

I will try a 11-21 cassette at some point but it is actually cheaper to buy a new crank set than a 11-21 cassette. I´m currently using a 11-23 which works but is not optimal around the larger cogs. A 12-23 would be better but with the compact cranks I do still need the 11 around here. I´m a heavy rider and for me it´s easier to turn big gears than it is to pedal faster.


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