Bicycle Mechanics - old bike , new cranks

sorry if this has been asked but can i put on a new crank and bb on a older bike and keep everything else the same? eng threads, friction shift , 3/32 chain 6 or 7 speed freewheel. been out of the tech loop for so long . whats the difference between a new carbon crank today ? is there a difference in the width of the chainrings that wont alow me to use it with an older friction set up? just curious.

Everything should be fine. The standard is a 3/32 chain, the difference between the speeds is the thickness of the chain. A good 8 speed chain will be fine. You can actually use a 9 or 10 speed chain, but they are usually more expensive and don't last as long. New cranksets will work fine.

What do you mean by "whats the difference between a new carbon crank today"? Do you mean the difference between carbon cranks of today as oppose to older carbon cranks? Or do you mean what is the difference between carbon cranks and older aluminum? They are made of carbon fiber. They are lighter.

With friction shifting, your shifters will work with any speed crankset.

why new cranks??

carbon cranks are a joke. your not even really saving that much weight. with carbon you are just allowing flex and on a very important component such as cranks you do not want fex. you gain back the extra weight with the power you produce on a standard aluminum/steel crank.

I ride a 70s Le Tour. It was all stock until a few months ago when the bolt sticking out of the BB snapped, and the whole left side crank fell off. I landed on my thigh hard (corked thigh) and couldn't walk properly for a month.

Anyway, I replaced it with a double 105, and it's like a new bike! Stock RD, stock cassette, new chain, BB, and crankset.

You're fine. I'd stick with 7/8 speed chains. SRAM PC-46/58 are good and reasonably priced.

Modifying one of the Gitanes?

You're fine. I'd stick with 7/8 speed chains. SRAM PC-46/58 are good and reasonably priced.

Modifying one of the Gitanes?

no i have a 80's carbon vitus im tinkering with , seeing how light i can get it . im turning it into a tt bike to play with and not have to spend big $$ on. im puting on some old and some new.i put on modolo cabon friction shifters , bought some rev-x carbon tubular wheels with the screw on freewheel, putting on a six speed maillard freewheel that comes in at 145grms, looking for a regina hollow pin chain . i was just wondering if a stronglight carbon crank would work with the old chains, if there was any difference in thickness of the chainrings or spacing between the teeth that would give me probs going from big ring to small or vice versa and if i would have any probs with friction shifting. im using huret jubilee derailleurs.
i was wondering if they make a carbon seat post in a 23.9 mm , but i havent seen any. i have a light rubis in there now. so no biggy if they dont. going to put on a light carbon saddle. it has a stronglight a-9 headset , takes a 1 inch quill, i see cinelli makes a 1 inch stub quill so you can put on the new type stem and tt bars setup . wolber neo pro 18 sewups . its has taken me awhile to piece it together. like i said a mix and match of new and old.

no i have a 80's carbon vitus im tinkering with , seeing how light i can get it . im turning it into a tt bike to play with and not have to spend big $$ on. im puting on some old and some new.i put on modolo cabon friction shifters , bought some rev-x carbon tubular wheels with the screw on freewheel, putting on a six speed maillard freewheel that comes in at 145grms, looking for a regina hollow pin chain . i was just wondering if a stronglight carbon crank would work with the old chains, if there was any difference in thickness of the chainrings or spacing between the teeth that would give me probs going from big ring to small or vice versa and if i would have any probs with friction shifting. im using huret jubilee derailleurs.
i was wondering if they make a carbon seat post in a 23.9 mm , but i havent seen any. i have a light rubis in there now. so no biggy if they dont. going to put on a light carbon saddle. it has a stronglight a-9 headset , takes a 1 inch quill, i see cinelli makes a 1 inch stub quill so you can put on the new type stem and tt bars setup . wolber neo pro 18 sewups . its has taken me awhile to piece it together. like i said a mix and match of new and old.


I know the Jubilee is light - but I'm not sure the exact weight. You might want to look at a Suntour Cyclone Mk II @ 170g. Suntour's slant parallelogram will shift better.

Chainrings are a little thinner but you'll be OK. 8 and 9s rings are the same distance apart as the old stuff. 10s rings are spaced a little closer together and 'might' present an issue.

I know the Jubilee is light - but I'm not sure the exact weight. .

front is 80 grms ,rear is the drilled out cage model, weighs 135 grms.