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Tourist
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Discussion Starter · #1 ·
All I see these days are 'compact' cranksets with 34-50 rings (or 36-50). Are there any ultra-compact cranksets compatible with 11spd drivetrains? E.g. 30-46, or 28-42 like on a mtb, or even better something like 28-44 or 26-42 ? I understand there is a BCD issue, so is there any 11spd offering with low gears, which would be perfect for touring people? And if there is anything available, what front derailleur would you use? This is for a standard road bike that currently has 10+y old DA7803 on it. Thanks!
 

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An alternative is just to fit a MTB crankset.

A 10-speed crankset will work just fine on an otherwise 11-speed system. The chains have the same internal width.

I used a Deore crankset and FD to achieve 40/28 gearing on a gravel bike. The chainline can be set up the same as a road bike, the only drawback is that the Q factor will increase. Never bothered me. You need the Deore FD as the cage of a road FD will not clear the chainstay.
 

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Tourist
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Discussion Starter · #5 ·
Thanks, didn't know that 10spd chains and 11spd had same internal width.

For Q-factor, if I understand correctly the road width of the BB shell is 68mm, while the mtb width is 73mm, so that I'll have to put 5mm of spacers? I guess the amount of spacers on each side depends on what's needed to keep a good chainline?
 

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Thanks, didn't know that 10spd chains and 11spd had same internal width.

For Q-factor, if I understand correctly the road width of the BB shell is 68mm, while the mtb width is 73mm, so that I'll have to put 5mm of spacers? I guess the amount of spacers on each side depends on what's needed to keep a good chainline?
Deore comes with spacers to fit a 68 mm shell.

The Q factor is greater because it's a MTB crank, not because of spacers.
 

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Yeah my Deore M590 mountain triple came with 3 x 2.5 mm spacers. You add or remove two of the spacers to accommodate 68 or 73 mm shell width.

I put this crank on a 68 mm BSA road frame. I "modified" the setup by putting all three spacers on the non-drive (left) side. That pulled the chain rings to the left and gives a chainline similar to (the same as?) my road cranks. Of course the pedals are both slightly offset to the left :)

Then I removed one of the spacers and with a file extended the hole that the little Hollowtech safety clip* slots into. That reduced the Q factor somewhat and reduced the leftward bias of the pedals somewhat.

So now I have 2x 2.5 mm spacers on the non drive side (left); zero spacers on the drive side; my chainline is (mostly?) correct; my pedals are (I think) 2.5 mm offset to the left; I have invalidated my warranty; and I have probably exposed myself to risk of accident, injury or DEATH with my modifications.

The crank worked well out of the box. My subsequent modifications seem OK, but only a few hundred miles so far. I wouldn't recommend my modifications unless you know what you are doing, and there may be horrible consequences I'm not aware of (eg DEATH)

The wider pedalling stance (Q factor) is a minor issue, I would prefer a road Q factor. I notice it the first time I get out of the saddle on this bike, the bike twists a lot more than with my normal road cranks. Takes a few seconds to get used to. But not the end of the world.

I don't see why you couldn't do this with a Deore double. I also understand 9, 10, 11 speed cranks are all pretty much interchangeable, though I have not tested this.

Like you, I would be interested in granny gears with a road Q factor. Not paying for those FSA carbon ones though!!!

Good luck

*bikerjulio may beat me up on my use of the word "safety", but I think it's appropriate for Hollowtech II :) ;)
 

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Re the spacers on the Deore crankset. Mine was a double. I remember I went through some measurements and thinking at the time and decided on one spacer on the DS and two on the NDS. Everything worked out just fine.

The Deore FD can be set up as either top or bottom pull.

Bicycle tire Bicycle frame Wheel Bicycle wheel rim Bicycle part
 

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The issue of chain width is commonly misunderstood. Our friend Lennard Zinn had this explanation:

Chain width, as defined by standard methods of measuring chains, is 3/32-inch on all bicycle derailleur chains. But this is NOT the “width” people are talking about when they say, “an 11-speed chain is narrower than a 10-speed (or 9-speed or 8-speed, etc.) chain.” Yes, chains have gotten narrower as the number of rear cogs has increased in bicycle drivetrains, BUT it is only the outside width dimension that has decreased, and really, we are actually describing the length of the roller pins, which is shorter on 11-speed chains than on 10-speed chains.

When we’re discussing differences in width of differing-speed chains, we should call this dimension (the length of the roller pins) something like “outer chain width” or “chain outer width.”

The actual “chain width,” which we in the bike industry should perhaps instead call “chain inner width,” has not decreased.

Another way to say this is that the width of the rollers has stayed nominally the same through all of these changes in speeds. What has happened, however, is that the extension of the roller pins to the outside of the outer link plates has decreased. The ends of the pins are practically flush with the faces of the outer link plates on 11-speed chains, leading to much more complex methods of chain joining to not have chain breakage.
and also this:

The spacing between front chainrings has not decreased on 11S drivetrains from 10S ones...............
Complete piece here Tech FAQ: Chain width explained, compatibility queries answered | VeloNews.com
 

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Re the Deore front derailleur, they make it in "top swing" and "bottom swing" versions. Functionally I think they are the same. I got the "top swing" which in hindsight might have been a mistake. The derailleur clamp sits very low on the seat tube. Made it really hard for me to fit a chain catcher (Deda dog tooth) in. Also if your seat tube flares out where it meets the BB you could have issues. I think "bottom swing" version is more like a road FD where the clamp is quite high, above the chainrings. Not sure though.

I got it all to work OK in the end, but "bottom swing" might have been slightly less hassle.

I think BikerJulio has the "bottom swing", looking at his photo. Clever chap.

Not sure if the Deore FD cable pull is compatible with your 7803 levers. You might have issues there. If so you might be able to modify the FD - I did to get it to work with my Campag levers. Hopefully some expert will chip in - I have no idea.
 

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@BikerJulio

Tell me about your canti brakes. Shimano? What pads?

We look like we have similar gravel setups. My cantis suck. Tektro CR520, ultra cheap. Also tried Tektro mini-Vs. Sucked too. For both kinds the stock rubber was useless, I swapped for Kool Stop Salmon MTB pads and went through Sheldon Brown's stuff on matching the mechanical advantage. They still suck.

Where I am now:- Campag 10s levers + Tektro CR520 brakes + Kool Stop Salmon MTB pads. Mechanical advantage similar to my Campag road brakes, probably somewhat higher to compensate for canti disadvantages.

Lever feel and travel is OK, comparable to my roads, but braking sucks. Have to haul on the levers like crazy compared to road brakes.

Was gonna post a separate thread but your photo has intrigued me....

cheers

[/thread hijack]
 

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Hmm. I don't remember all that about the Deore FD. Mine was a 10-speed that was "dual pull". Perhaps the design had changed since @cheaps one? Here's a close up

Bicycle tire Wheel Bicycle part Bicycle wheel rim Spoke

I think it was probably this one wiggle.com | Shimano FD-M591 Deore Hybrid Top-Swing Front Derailleur | Derailleurs Front - MTB

Top Features of the Shimano FD-M591 Deore Hybrid Top-Swing Front Derailleur

Light action top swing design
Multi-fit compatibility means that this front derailleur will fit any frame type or seat tube size
Cable routing can be used with frames built for top or bottom pull derailleurs
Mega9 drivetrain compatibility
Reinforced steel chain guide offers high strength and rigidity for improved shifting response
Maximum capacity of 22 teeth, and up to 48 tooth chainring
For 63-66 degree chainstay angle
 

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check my edit
 

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Thanks, didn't know that 10spd chains and 11spd had same internal width.

Not exactly. It's just that the difference in width isn't enough to affect front shifting. It is critical in the rear where there are fewer teeth to share the load.
 

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@BikerJulio

Tell me about your canti brakes. Shimano? What pads?

We look like we have similar gravel setups. My cantis suck. Tektro CR520, ultra cheap. Also tried Tektro mini-Vs. Sucked too. For both kinds the stock rubber was useless, I swapped for Kool Stop Salmon MTB pads and went through Sheldon Brown's stuff on matching the mechanical advantage. They still suck.

Where I am now:- Campag 10s levers + Tektro CR520 brakes + Kool Stop Salmon MTB pads. Mechanical advantage similar to my Campag road brakes, probably somewhat higher to compensate for canti disadvantages.

Lever feel and travel is OK, comparable to my roads, but braking sucks. Have to haul on the levers like crazy compared to road brakes.

Was gonna post a separate thread but your photo has intrigued me....

cheers

[/thread hijack]
Avid Shortys. The kind with the regular shimano pad holders. Stock pads. I never did enough to wear out any. Need to be toed in a fraction, but worked OK for me.
 

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@OP

re front derailleurs, swing schming, we are clearly all confused about this top vs bottom stuff.

There is another wrinkle, Shimano makes a "trekking/hybrid" version for up to 48t big ring and a "MTB" version for 44t big ring. Or something like that.

I think they all handle cable up from the bottom or down from the top (dual pull)

Anyway you want to go down that road come back on here and we'll sort ourselves out properly.

I think a Deore double crank + FD will do exactly what you want and is cheap as chips.

The downsides:-
- compared to your DA it's fugly (IMHO), looks like it's made out of old beer cans; and
- the wide stance (Q factor) could irritate you.
 

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@OP

re front derailleurs, swing schming, we are clearly all confused about this top vs bottom stuff.

There is another wrinkle, Shimano makes a "trekking/hybrid" version for up to 48t big ring and a "MTB" version for 44t big ring. Or something like that.

I think they all handle cable up from the bottom or down from the top (dual pull)

Anyway you want to go down that road come back on here and we'll sort ourselves out properly.

I think a Deore double crank + FD will do exactly what you want and is cheap as chips.

The downsides:-
- compared to your DA it's fugly (IMHO), looks like it's made out of old beer cans; and
- the wide stance (Q factor) could irritate you.
No confusion here except what you caused :) I posted the Deore FD I used.

The Deore crank is a thing of great functional beauty. Much nicer than some of their other cranks.

I never noticed the Q factor thing which is the same as every MTB rider uses. It's all BS.
 
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