mechanicmatt

Any of you try a newer Shimano 10 speed compact crankset (Ultegra) paired with a 7 spd Shimano compatible rear? It would be all friction shifting?

I also asked this on my project thread and didn't know if anyone saw the question.

shoota 

I don't think the rd has much of anything to do with this. I'm assuming your fd will be friction as well? I can't imagine this wouldn't work, even with a 7s chain.

edit: don't forget to Google in the future: https://www.bikeforums.net/bicycle-m...rivetrain.html

Andy_K 

Mechanically, it should work just fine. Aesthetically, they may be incompatible.

mechanicmatt

, it's what I have though.

Spaghetti Legs 

I think it would work fine. I’ve used a Velo Orange compact crank (I believe designed for 10 speed ) with a 6 speed friction setup without problems. I use 8 speed chains on all my 6 thru 8 speed bikes.

plonz 

I use a Velo Orange compact crank with a 6 speed Shimano 600 Arabesque group and an 8 speed KMC chain. The Velo Orange crankset is 10 spd compatible so it has more narrow spacing between the rings. I bring this up because the front derailleur is pretty finicky when shifting to the big ring. If I shift too fast, the chain will bind mid shift between the rings. Not sure if this is due to the wider 8 speed chain or the Arabesque FD trying to handle the small-to-big walk on the compact crank. I’m using the appropriate VO BB but I suppose the chainline could be a contributor as well.

Bonus data point: The previous crankset was a Dura Ace 7400 7spd crank (not compact). All other parts remained the same (after resizing the chain) and the FD upshifted just fine.

Assuming OP is using a 7spd FD, I’d think there is a chance you might run into a similar issue. Not a show stopper IMO, just need to modulate FD upshift accordingly.

mechanicmatt

Actually I've had a lot of luck with 7spd front derailleurs with 9 and 10 spd setup. I was just worried a 7 spd chain wouldn't work with the crankset.

RobbieTunes

would you like a 7sp crankset and bb?

mechanicmatt

I have some I just don't have a compact or triple with a low gear. I'm trying to put something together for the climbing around here. Appreciate the offer.

mechanicmatt

Everything I have to work with. A nice Campy Strada crank but it may be the only campy components I have. Shimano 600 that I can convert to 52-39 rings. Sugino Impel mtb crankset that have a bcd less than 110bcd, I'd have to scavenge for chainrings for it. Some Bulletproof branded 110bcd crank that I think may be meant for single speed setups, got it extra in a trade. Then the Shimano compact crankset that I'm talking about. Lastly a bunch of chainrings.

RobbieTunes

I can still "go there." 3x7 compact triple. Square taper....

mechanicmatt

...what would you put on this bike?

RobbieTunes

6sp. Freewheel, 3x7 RSX compact triple cranks, Suntour Mountech FD, long cage DA 7400 RD, 2/3x6 DA downtube shifters set to friction, or 7sp freewheel, 2/3x7 105 downtube shifters, pick an RD.

PM implied.

mechanicmatt

Thanks Robbietunes. I'll PM later. I only need a crankset. I have plenty of derailleurs long and short, shifters will be Suntour barcons, I may change the levers out to Shimano with cables coming out of the top. I want to build this up for the Cino and I'm just not using the Shimano compact because it doesn't look right. That's a seven speed rear, Sunrace 13-28 that I will be using.

DorkDisk

I have the MTB variant of this: 7 sp XT hub, thumb shifters, and front derailleur with 7 cogs off an 8 sp SRAM cassette, 9 sp chain, and a 10 sp SLX crankset.



Similar is this tricolor derailleurs with 8sp XT cassette, 8 sp Shimano chain and 11sp GRX crankset.

mechanicmatt

Perfect! that's the kind of proof i was looking for.

Classtime 

mechanicmatt
i couldn't not comment on your workbench. New? Pretty cool.

bikemig 

110 bcd cranks for vintage bikes are fairly inexpensive and easy to find if you are willing to use a 110/74 bcd triple and use only the 2 outer rings.

mechanicmatt

Thanks, It's new I guess, I'm working on it. It's basically done, the other tool cabinet to go in is full of tools so I will wait to put that in when I move it to it final resting place. Lots of wood leftovers were used to build.

Current state:

clubman 

Just remember, it's the 8 speed cogs that allow the chain to work properly with the crank.