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fogrider
06-24-2018, 07:28 PM
So I've had my Santa Cruz on the road/dirt for almost 6 months, and it's been great fun! I've been running a 1x drivetrain and the gearing had been fine for my purposes. But what I've noticed is clutch actually sucks wattage. So if I go to a 2x, I can go with a non clutch rear mech and that should free up the drivetrain. Has anyone tried this? https://uploads.tapatalk-cdn.com/20180625/86b72308f7c9c18a31da68de16830604.jpg

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Mikej
06-24-2018, 07:33 PM
You can loosen up the clutch - its Shimano?

batman1425
06-24-2018, 07:50 PM
How can you tell the clutch is "sucking wattage"? The clutch shouldn't add any additional tension, just prevents it from bouncing around on rough terrain. I highly doubt you'd see world tour riders using Di2 clutch derailleurs (like was done in the spring classics this year), if they were slowing them down. As mentioned above, you can also turn the clutch off.

kppolich
06-24-2018, 08:00 PM
What's the goal here?

Save wattage and go faster or have a wider range of gears?

If the first, remove all that extra 'stuff' on your bike, pick a faster tire, or wear some tighter clothes.

If the later, go 2x

Or replace the RD with a non clutch and forget about it Narrow/Wide front chainring should keep the chain on 90% of the time anyway.

fogrider
06-24-2018, 08:22 PM
What's the goal here?

Save wattage and go faster or have a wider range of gears?

If the first, remove all that extra 'stuff' on your bike, pick a faster tire, or wear some tighter clothes.

If the later, go 2x

Or replace the RD with a non clutch and forget about it Narrow/Wide front chainring should keep the chain on 90% of the time anyway.

Extra stuff? I've got lights (safety first), sealant and spare tube, a pump (I drop the psi when I get into dirt with ruts and pump it back up for the road. this tire is a good for both - this bike is meant for both) and the backpack is for the outing of the afternoon (I did most of my ride without it, but am looking for a small handlebar bag).

How can you tell the clutch is "sucking wattage"? The clutch shouldn't add any additional tension, just prevents it from bouncing around on rough terrain. I highly doubt you'd see world tour riders using Di2 clutch derailleurs (like was done in the spring classics this year), if they were slowing them down. As mentioned above, you can also turn the clutch off.

I'm not sure all the sucking is from the rear mech...maybe I've got the chain too short...but just spinning the crank backwards is not as smooth as my other bikes!

sitzmark
06-24-2018, 08:53 PM
I ran a sram red 22 w/ WiFli RD 2x -> 10-40 (modified xg-1199 cassette) for a one-off application last year.

Worked fine with a wolftooth adapter, longer chain, and b-screw adjust. Some gravel but mostly paved road, so tension wasn't overly challenged. Low range reserved for 20-25% section of Lincoln gap on VT 6-Gap loop. Definitely overkill, but first time riding the gaps so didn't know what to expect - was determined not to put a foot down on any part of the climbs and it worked. (Even the 30 somethings in the group put a foot down/walked on Lincoln. They razzed me for the dinner plate cassette at the start of the ride - I waited at the top of Lincoln for all of them. Cheating? ... maybe. Didn't care.:p)

Compact crank gave me more than enough low end to climb a tree and still have gears to ride the flats between gaps. 2 tooth jumps from 10-18 which caused a little "hunting" for the right gear on the flats but overall no complaints and zero issues.

CiclistiCliff
06-24-2018, 08:55 PM
Extra stuff? I've got lights (safety first), sealant and spare tube, a pump (I drop the psi when I get into dirt with ruts and pump it back up for the road. this tire is a good for both - this bike is meant for both) and the backpack is for the outing of the afternoon (I did most of my ride without it, but am looking for a small handlebar bag).



I'm not sure all the sucking is from the rear mech...maybe I've got the chain too short...but just spinning the crank backwards is not as smooth as my other bikes!

That’s not the clutch.

That’s the narrow/wide chainring and MOSTLY your freehub

Ronsonic
06-24-2018, 09:04 PM
Can't you just turn off the clutch on those? Unless that bike is doing crazier stuff than my full-sus trail bike you'll be just fine without it.

fogrider
06-25-2018, 12:04 AM
That’s not the clutch.

That’s the narrow/wide chainring and MOSTLY your freehub

I can't do much with the narrow/wide...I could try lubing the freehub...

CiclistiCliff
06-25-2018, 01:31 AM
Just ride.....

Stop over thinking it so much. If pros ride it, why not ride it?

And when do you pedal backwards to propel yourself forward?

HTupolev
06-25-2018, 02:30 AM
I'm not sure all the sucking is from the rear mech...maybe I've got the chain too short...but just spinning the crank backwards is not as smooth as my other bikes!
How unsmooth is unsmooth?

If I go through my stable and spin the cranks backwards to see how long it takes for them to come to a stop, my cheapo gravel bike - with a UN55 bottom bracket and Acera M360 derailleur and dirt cheap freehub - totally wrecks all my other bikes. Why? Who knows. But the momentum of a spinning drivetrain is pretty low, and the frictions involved in slowing one down quickly aren't necessarily very significant, so I mostly just don't think about it.

If it's something you can feel in the legs, look into it. If it's something you can only feel lightly in the fingers, eh whatever.

sitzmark
06-25-2018, 07:42 AM
I'm not sure all the sucking is from the rear mech...maybe I've got the chain too short...but just spinning the crank backwards is not as smooth as my other bikes!

https://youtu.be/Ew03wbHOHS0