Sram Rival AXS

Discuss light weight issues concerning road bikes & parts.

Moderator: robbosmans

DaveS
Posts: 3438
Joined: Fri Mar 24, 2006 1:26 pm

by DaveS

talltales wrote:
Thu Apr 22, 2021 5:43 pm
#40. Thanks, but that doesn't answer the question. What is the real, measured diameter? Standard chains are #41, except the only chains with that big rollers are one speed chains, according to my vernier at least?
I posted the diameter standard of .3125 maximum and the fact that most rollers are made to be about .001 inch smaller, so that is .3115 inch. That's what my micrometer says. It's easy to take a roller out of some cut off pieces. A Campy chain roller will measure about .305 inch.

Fixed my typo. .3125 -.001= .3115 I just say .006 inch larger than a standard chain.
Last edited by DaveS on Fri Apr 23, 2021 12:41 am, edited 2 times in total.

by Weenie


Visit starbike.com Online Retailer for HighEnd cycling components
Great Prices ✓    Broad Selection ✓    Worldwide Delivery ✓

www.starbike.com



goatalope
Posts: 71
Joined: Sun Sep 04, 2016 3:14 pm

by goatalope

Is this the death of mechanical Sram drivetrains? I've been hoping for 12 speed mechanical Sram. Could use AXS crank, cassette, chain, brake calipers. Minor revisions to existing mechanical ders. Slim down bulbous hood on current shifters. Maybe just Apex and Force trim. But probably a pipedream.

Based on how often my phone battery dies, my garmin dies, my Xbox controllers die, etc. while using them, I am not a candidate for battery based drivetrains.

talltales
Posts: 185
Joined: Mon Mar 11, 2019 10:43 pm

by talltales

That is not what you said before and 0.03125-0.001 is not 0.0315. But never mind, I assume its typos. But just to clarify, - you measured a AXS roller tol 0.315" (8.00mm) ?

talltales
Posts: 185
Joined: Mon Mar 11, 2019 10:43 pm

by talltales

goatalope wrote:
Thu Apr 22, 2021 8:38 pm
Is this the death of mechanical Sram drivetrains? I've been hoping for 12 speed mechanical Sram. Could use AXS crank, cassette, chain, brake calipers. Minor revisions to existing mechanical ders. Slim down bulbous hood on current shifters. Maybe just Apex and Force trim. But probably a pipedream.

Based on how often my phone battery dies, my garmin dies, my Xbox controllers die, etc. while using them, I am not a candidate for battery based drivetrains.
A tiny dynamo would do it. A DI2 bettery is said to last at LEAST 2000km. Assuming an average speed of 30km/h that is 66 hours (very low ball). Its a 3.7wh battery. Thus the average power draw is about 0.06w ... hardly noticable if it was to be supplied from a tiny dynamo. Cant imagine why its not built into a jockey wheel ;-)

sebejo
Posts: 29
Joined: Wed Oct 10, 2018 3:25 pm

by sebejo

How much of the Rival derailleur extra weight coming from the cage and pulleys vs. the upper part? In other words how much heavier is the Rival cage assembly compared to Red/Force?

raggedtrousers
Posts: 200
Joined: Wed Dec 09, 2020 9:29 pm

by raggedtrousers

talltales wrote:
Thu Apr 22, 2021 8:50 pm
goatalope wrote:
Thu Apr 22, 2021 8:38 pm
Is this the death of mechanical Sram drivetrains? I've been hoping for 12 speed mechanical Sram. Could use AXS crank, cassette, chain, brake calipers. Minor revisions to existing mechanical ders. Slim down bulbous hood on current shifters. Maybe just Apex and Force trim. But probably a pipedream.

Based on how often my phone battery dies, my garmin dies, my Xbox controllers die, etc. while using them, I am not a candidate for battery based drivetrains.
A tiny dynamo would do it. A DI2 bettery is said to last at LEAST 2000km. Assuming an average speed of 30km/h that is 66 hours (very low ball). Its a 3.7wh battery. Thus the average power draw is about 0.06w ... hardly noticable if it was to be supplied from a tiny dynamo. Cant imagine why its not built into a jockey wheel ;-)
Self-charging Di2! I have no idea as to whether or not this is plausible, but that would be very cool.

DaveS
Posts: 3438
Joined: Fri Mar 24, 2006 1:26 pm

by DaveS

talltales wrote:
Thu Apr 22, 2021 8:41 pm
That is not what you said before and 0.03125-0.001 is not 0.0315. But never mind, I assume its typos. But just to clarify, - you measured a AXS roller tol 0.315" (8.00mm) ?
Sorry for the typo, but 5/16 inch = .3125. Subtract .001 inch and you get .3115. I just say it's .006 inch larger in diameter or .003 inch larger radius, than #41 chain which is what counts. That's the thickness of an average piece of paper. The difference in radius is unlikely to ever cause a problem. The rollers will just contact the teeth at a slightly higher location. It's the narrow inner plate width that could interfere with using some 11 speed cranks, but the Campy 12 chain is just as narrow across the inner plates.

A SRAM dealer on facebook tried to claim that the AXS chain would only contact one tooth and create fast chain wear, but that's totally wrong, since both chains have the same pitch. I've used the AXS chain on standard chainrings and sprockets long enough to notice faster wear and I've not seen that.

https://en.wikipedia.org/wiki/Roller_chain
Last edited by DaveS on Fri Apr 23, 2021 12:42 am, edited 2 times in total.

tomato
Posts: 436
Joined: Mon Jul 01, 2019 8:37 pm

by tomato

DaveS wrote:
Thu Apr 22, 2021 9:58 pm
talltales wrote:
Thu Apr 22, 2021 8:41 pm
That is not what you said before and 0.03125-0.001 is not 0.0315. But never mind, I assume its typos. But just to clarify, - you measured a AXS roller tol 0.315" (8.00mm) ?
Sorry for the typo, but 5/16 inch = .03125. Subtract .001 inch and you get .03115. I just say it's .006 inch larger in diameter or .003 inch larger radius, which is what counts.
I think you need to replace the batteries in your calculator.

talltales
Posts: 185
Joined: Mon Mar 11, 2019 10:43 pm

by talltales

raggedtrousers wrote:
Thu Apr 22, 2021 9:47 pm
talltales wrote:
Thu Apr 22, 2021 8:50 pm
goatalope wrote:
Thu Apr 22, 2021 8:38 pm
Is this the death of mechanical Sram drivetrains? I've been hoping for 12 speed mechanical Sram. Could use AXS crank, cassette, chain, brake calipers. Minor revisions to existing mechanical ders. Slim down bulbous hood on current shifters. Maybe just Apex and Force trim. But probably a pipedream.

Based on how often my phone battery dies, my garmin dies, my Xbox controllers die, etc. while using them, I am not a candidate for battery based drivetrains.
A tiny dynamo would do it. A DI2 bettery is said to last at LEAST 2000km. Assuming an average speed of 30km/h that is 66 hours (very low ball). Its a 3.7wh battery. Thus the average power draw is about 0.06w ... hardly noticable if it was to be supplied from a tiny dynamo. Cant imagine why its not built into a jockey wheel ;-)
Self-charging Di2! I have no idea as to whether or not this is plausible, but that would be very cool.
Sure, why not. The above was kind of tongue in cheek, but I cant see fault with the calculation. Thus a tiny dynamo and a much smaller battery, to hold charge, would suffice. It might not add any weight at all. Of course ppl would instantly reject a dynamo on a race bike, but the loss it tiny and the fear imagined.

talltales
Posts: 185
Joined: Mon Mar 11, 2019 10:43 pm

by talltales

DaveS wrote:
Thu Apr 22, 2021 9:58 pm
talltales wrote:
Thu Apr 22, 2021 8:41 pm
That is not what you said before and 0.03125-0.001 is not 0.0315. But never mind, I assume its typos. But just to clarify, - you measured a AXS roller tol 0.315" (8.00mm) ?
Sorry for the typo, but 5/16 inch = .03125. Subtract .001 inch and you get .03115. I just say it's .006 inch larger in diameter or .003 inch larger radius, than #41 chain which is what counts. That's the thickness of an average piece of paper. The difference in radius is unlikely to ever cause a problem. The rollers will just contact the teeth at a slightly higher location. It's the narrow inner plate width that could interfere with using some 11 speed cranks, but the Campy 12 chain is just as narrow across the inner plates.

A SRAM dealer on facebook tried to claim that the AXS chain would only contact one tooth and create fast chain wear, but that's totally wrong, since both chains have the same pitch. I've used the AXS chain on standard chainrings and sprockets long enough to notice faster wear and I've not seen that.

https://en.wikipedia.org/wiki/Roller_chain
You are Way off. - And one inch is 25.4mm. Thus the roller diameter is in the ~0.3" range, not ~0.03". However no calculation or conjecture is needed. I was asking for the measured diameter. You claim to have measured it. What is it?

DaveS
Posts: 3438
Joined: Fri Mar 24, 2006 1:26 pm

by DaveS

Man my brain is not working. 5/16 inch is .3125. Minus .001 is .3115. That's what I measured. They told me not to drive or operate machinery today. Now I know why. Propofal has longer lasting effects than I thought.

All that said, somebody should have figured out that 5/16 inch is 0.3125 and .001 less is 0.3115.

TobinHatesYou
Posts: 8283
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

sebejo wrote:
Thu Apr 22, 2021 9:14 pm
How much of the Rival derailleur extra weight coming from the cage and pulleys vs. the upper part? In other words how much heavier is the Rival cage assembly compared to Red/Force?

The Rival AXS FD is only 10-11g heavier than a Red AXS FD.
The RD is >30g heavier and the extra weight evenly distributed between the body and cage.

DaveS
Posts: 3438
Joined: Fri Mar 24, 2006 1:26 pm

by DaveS

TobinHatesYou wrote:
Fri Apr 23, 2021 12:50 am
sebejo wrote:
Thu Apr 22, 2021 9:14 pm
How much of the Rival derailleur extra weight coming from the cage and pulleys vs. the upper part? In other words how much heavier is the Rival cage assembly compared to Red/Force?

The Rival AXS FD is only 10-11g heavier than a Red AXS FD.
The RD is >30g heavier and the extra weight evenly distributed between the body and cage.
Good to know. If the longevity is similar, it's a bargain. I haven't seen any info about rotors, whether included with the shifters and calipers.

TobinHatesYou
Posts: 8283
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

DaveS wrote:
Fri Apr 23, 2021 12:57 am

Good to know. If the longevity is similar, it's a bargain. I haven't seen any info about rotors, whether included with the shifters and calipers.

Actually I misread. ~15g heavier for the FD, ~60g heavier for the RD.

If piecemealing a mixed bang for the buck group together I would likely go with at least the Force RD (better clutch,) Rival FD, Rival shifters/calipers, Red cranks, 4-bolt spider+chainrings, Red cassette, Rival chain, Centerline X rotors.

JMeinholdt
Posts: 668
Joined: Wed Feb 26, 2020 10:31 pm
Location: Topeka, KS

by JMeinholdt

TobinHatesYou wrote:
Fri Apr 23, 2021 1:16 am
DaveS wrote:
Fri Apr 23, 2021 12:57 am

Good to know. If the longevity is similar, it's a bargain. I haven't seen any info about rotors, whether included with the shifters and calipers.

Actually I misread. ~15g heavier for the FD, ~60g heavier for the RD.

If piecemealing a mixed bang for the buck group together I would likely go with at least the Force RD (better clutch,) Rival FD, Rival shifters/calipers, Red cranks, 4-bolt spider+chainrings, Red cassette, Rival chain, Centerline X rotors.
I think you're right on the money as far as value to weight ratio is concerned with this build. When I built my Force group up it was clear that the cranks and cassette are by far the best way to save weight on an AXS build.
Wilier Cento10AIR Rim Brake - SRAM Force AXS
3T Exploro 105 - Gravel/Commuter/Trainer

Strava link: https://www.strava.com/athletes/jmeinholdt
YouTube link: https://www.youtube.com/c/JMCyclingVideos1

by Weenie


Visit starbike.com Online Retailer for HighEnd cycling components
Great Prices ✓    Broad Selection ✓    Worldwide Delivery ✓

www.starbike.com



Post Reply