Convert Compact crank

...sorry...I meant 53/39, not 58....

Jay

JayKrause said:

Can I get new Ultegra chain rings and convert my 58/39 to a 50/34???

Thanks
Jay

No, the pcd (diameter of the chainring bolts on the chainset) will not allow you to go as low as a 34 chainring on a normal chainset, usually the smallest is about 38 depending on whether or not they manufacture one, the 50 should be no problems again if they make one. But a 50/39 should be fine for alot of riding. Im looking at a compact with a 50/ 36 for day to day riding

JayKrause said:

...sorry...I meant 53/39, not 58....

Jay

Fignon le Grand said:

No, the pcd (diameter of the chainring bolts on the chainset) will not allow you to go as low as a 34 chainring on a normal chainset, usually the smallest is about 38 depending on whether or not they manufacture one, the 50 should be no problems again if they make one. But a 50/39 should be fine for alot of riding. Im looking at a compact with a 50/ 36 for day to day riding

I added an FSA compact carbon crank (50/34) to my OCR1 (swapping out a 52/36) and it's been heavenly on the steep hills. You really don't lose a lot on the top end, either. I did switch out the Ultegra front derailleur to an FSA compact derailleur as the shifting wasn't as smooth as before. The compact derailleur follows the smaller circumference of the compact crank and therefore, results in better shifting. Overall, well worth the money.

itsboz said:

I added an FSA compact carbon crank (50/34) to my OCR1 (swapping out a 52/36) and it's been heavenly on the steep hills. You really don't lose a lot on the top end, either. I did switch out the Ultegra front derailleur to an FSA compact derailleur as the shifting wasn't as smooth as before. The compact derailleur follows the smaller circumference of the compact crank and therefore, results in better shifting. Overall, well worth the money.

¿ didn´t I hear that shimano are now , like campy , making a compact , or " gran fondo " , crankset ?
do check that you can fit it with your frame though , on some frames you can´t move the front mech down far enough or else the mech catches the frame at the bottom of it´s arc .

itsboz said:

I added an FSA compact carbon crank (50/34) to my OCR1 (swapping out a 52/36) and it's been heavenly on the steep hills. You really don't lose a lot on the top end, either. I did switch out the Ultegra front derailleur to an FSA compact derailleur as the shifting wasn't as smooth as before. The compact derailleur follows the smaller circumference of the compact crank and therefore, results in better shifting. Overall, well worth the money.

Did you also change out your rear sprockets to keep the same ratios as before?

My_Aching_Fiets said:

Did you also change out your rear sprockets to keep the same ratios as before?

Sorry, but yes, I swapped out from a 12-27 to a 12-25. I'm getting older (read fatter and weaker) so I can't push the taller gears too much anymore, so it wasn't too big a deal. Only the biggest/longest of climbs really kill me now. Overall in St. Louis Missouri, the hills can be steep, but they are generally not too long. I like the set-up and would strongly encourage it for others not really wanting to deal with a triple set-up. I had a triple on my road bike (didn't think too far ahead) and never really used the granny gearing.

I have a 2005 Giant TCR Composite 2 (XS/43cm) with a 12-25 cassette, and after about six months, swapped the Ultegra cranks (53/39, 165mm) to FSA Gossamer Compacts (50/34, 170mm).

With the Ultegra cranks, I found I never used the top 3 cogs when in the 53, but wished I had a few extra lower gears for big hills. I find I now use a larger range of my cassette when in the big ring (50), and really appreciate the extra low gears. Although 165mm cranks may be more my size, I do appreciate the bigger torque from the 170mm (which is what's on my MTB anyway).

No problems with shifting between the front rings. Didn't bother getting a compact specific front derailleur.

ksl said:

I have a 2005 Giant TCR Composite 2 (XS/43cm) with a 12-25 cassette, and after about six months, swapped the Ultegra cranks (53/39, 165mm) to FSA Gossamer Compacts (50/34, 170mm).

With the Ultegra cranks, I found I never used the top 3 cogs when in the 53, but wished I had a few extra lower gears for big hills. I find I now use a larger range of my cassette when in the big ring (50), and really appreciate the extra low gears. Although 165mm cranks may be more my size, I do appreciate the bigger torque from the 170mm (which is what's on my MTB anyway).

No problems with shifting between the front rings. Didn't bother getting a compact specific front derailleur.

So were you unable to find any compact setups that used the 165 mm crankarms? Anyone else know if this setup exists?

Shimano is introducing its own compact crank set for 2006 which is available in 165mm. The other brands (FSA, Truvativ) only go down to 170mm when I last checked their websites.

I went with the FSAs because they were $50 cheaper, available immediately, and was happy enough with 170mm cranks (same as my MTB). Weight difference was negligible for me - I think around 50g from memory.

ksl said:

Shimano is introducing its own compact crank set for 2006 which is available in 165mm. The other brands (FSA, Truvativ) only go down to 170mm when I last checked their websites.

I went with the FSAs because they were $50 cheaper, available immediately, and was happy enough with 170mm cranks (same as my MTB). Weight difference was negligible for me - I think around 50g from memory.

Thanks for the info!

I've been riding an FSA Carbon Pro Eilte compact for over a year now and have mixed feelings on the subject.

#1 - The shifting up front will never be as good as you had it with your standard derailer/crank. This, over time, becomes VERY frustrating.

#2 - It is true, you will use a greater range of your rear cassette but at the expense of having to switch back and forth between the little and big chainrings up front. What I mean is that with a 39 inner chainring and say, a 27/12 behind you, you'll be able to stay in the 39 for most, if not all of a standard ride using the 53 only occasionally for hammering flats or drafting. For the 34 tooth inner chainring you'll have with your compact the problem referenced in #1 above compounds as a 34 chainring is NOT, I repeat NOT enough gear to stay with for any reasonable period what-so-ever. THIS BECOMES A ROYAL PAIN IN THE SADDLE over time. You will find yourself constantly switching back and forth between the 34 and 50. The more you shift, the more your imperfect compact will tend to derail...the more frustrated you will become!

Maybe the new Shimano compact will be better and flawlessly shift?

Me, I've had it with the compact and am presently making plans to convert back to a Dura Ace FC-7800. Yes, I have an FSA 16T compact derailer and it does improve the shifting but not enough.

MRW

[font='Times New Roman'][font=Arial]I'm here to follow up on my previous post re: compact cranks. I just finished what will hopefully be my last ride on a compact crank and I’ve got more bad news. With the advent of Winter I’ve switched my training from mostly mountains to flat and rolling. Since I was riding mountains mostly in the summer I was able to forgive the 34 tooth inner crank when I ran out of gear while finishing a rolling hill out of the saddle. There’d be another heneous climb right ahead of me anyway. However, if you ride flats and rolling only and don’t run into any serious climbing you will find that the 34 tooth ring, even at 34/12 will not give you enough gear as you crest a hill. This is not the place where you’ll want to switch to the 50 either! I am so glad to be done with this thing![/font][/font]

mikael17128 said:

[font='Times New Roman'][font=Arial]I'm here to follow up on my previous post re: compact cranks. I just finished what will hopefully be my last ride on a compact crank and I’ve got more bad news. With the advent of Winter I’ve switched my training from mostly mountains to flat and rolling. Since I was riding mountains mostly in the summer I was able to forgive the 34 tooth inner crank when I ran out of gear while finishing a rolling hill out of the saddle. There’d be another heneous climb right ahead of me anyway. However, if you ride flats and rolling only and don’t run into any serious climbing you will find that the 34 tooth ring, even at 34/12 will not give you enough gear as you crest a hill. This is not the place where you’ll want to switch to the 50 either! I am so glad to be done with this thing![/font][/font]

I've got an FSA compact 50-34 with 12-25 cassette and I normally stay in the 50 ring and use the 15-17 cogs on the flats(cadence ~95). I use the 34 ring on hills. I like my compact crank very much.

JayKrause said:

Can I get new Ultegra chain rings and convert my 58/39 to a 50/34???

Thanks
Jay

no. you have to have crankarms with 110 bcd to hold the compact chainrings.