TTron

Out for a short 20 mile ride. Going up a shortly small hill. All of a sudden May rear cassette is spinning freely forward and backwards. No power to the wheel. It’s AXS Red etap on a less than year old SWorks Roubaix. Wife is on her way to pick me up. Ug. Any ideas?

cxwrench

What kind of wheels? Has the rear wheel been out of the bike and the cassette/freehub fell off? I have seen a couple of Roval wheels lately that had the drive ring in the hub shell come loose. Without seeing the wheel I'm just throwing stuff out there.

TTron

Update; NOW it works!!! All I did was put the bike in the car, drove home and took it out of the car. Did not remove the rear wheel, left it as is. What the heck! Yes Roval wheels

base2 

My vote is for stuck pawls from too thick or excessive grease application. Assuming you serviced it at some point with an incompatible grease to what was already there. The fix would be to grab a box of Q-tips & remove all the now waxy muck gumming up the works. Then reapply with a light layer of fresh bearing grease that's not too thick in consistancy.

Next up is a stripped out drive ring. I concur with cxwrench We've had a rash come through the shop recently.

If it's a DT Swiss style ratchet mechanism, it could be the engagement springs not driving the drive plate to engage the freehub body. Disassemble, clean, service with new lube & if needed replace the springs or other worn bits if needed.

The thing about servicable things is they need to be serviced every once in a while. Fortunately for you, hub service isn't usually very expensive.

TTron

Very strange! Went for an aggressive 20 min ride to make if fail. No luck.

The bike is 11 months old, bought it brand new.
Cassette has not been removed that I’m aware of.

~150 miles ago, my specialized dealer / bike shop replaced the chain. it wasn’t an exact axs red etap, but a sram flat chain replacement.

Bike had been working flawlessly!

dsbrantjr

Was the temperature cooler when the failure occurred? Was it warmer when it started working again?

Sy Reene

How does a cassette spin freely both or either direction if there's a chain attached to it?

Andrew R Stewart 

Really?? The cassette, on the freehub body, spins freely in both directions WRT the rest of the wheel.

The first thing I thought of, but doubt applies here, was water getting frozen the freehub body then melting out. But this usually results in the freehub body not spinning either way. Coastal locals can be harder on a bike then areas only a few dozen miles inland. I do agree with servicing the freehub body's internals and see what happens.

It is possible that a pawl or ratchet ring is hanging up due to too thick or gummy lube. Or that the spring driving that part is broken. Taking it apart likely will give more info. Please follow up here so we can learn what your solution is. Andy

Sy Reene

Yeah, I was trying to picture what happens with cassette spinning while crank isn't?

cxwrench

You're kidding, right?

Andrew R Stewart 

Pick up the rear end of the bike, rotate the rear wheel. If the freehub was not engaging then you could spin the rear wheel both ways without the cranks rotating too. For this problem to show doesn't require the cranks/chain to be the input. Andy

Sy Reene

No. How would a cassette spin backwards if you're not pedaling backwards?
Then the cassette is not the piece spinning, it's the wheels. The OP's story is he was going up a hill.. so presumably forward and the cassette was able to spin in both directions.

Warren128

It's probably stuck or sticky pawls in the freehub. You should probably remove, inspect, and clean and relube the freehub pawls and pawl spring even if it is working properly now.

cxwrench

Cassette spins when freewheeling, effectively spinning backwards. You don't have to back pedal to make this happen, it just spins faster when you do. Cassette ALSO spins freely when pedaling forwards, effectively no drive. Get it?

Andrew R Stewart 

Which side of the mirror is the "correct" side? Andy

Sy Reene

Ok, but I'm trying to picture what OP experienced when actually riding (forward) on a bike and chain is connected with a freewheel that isn't engaged. If the cassette is spinning forward when coasting then I'd think the chain would be dropped real quick, and to move forward it would have to fight the RD tension. If pedaling forward or just coasting, the cassette likewise can't spin in reverse as the chain (connected to the crank) wouldn't allow, And if pedaling backwards the cassette will spin at whatever speed you're pedaling backwards because the chain is pulling it.

I can imagine seeing the issue with bike on a stand and/or chain removed.

cxwrench

You're wayyyyyy overthinking this. The issue is that when the OP pedals forward there is no drive. That's it. It's not rocket surgery.

TTron

Correct, there was NO drive to the rear wheel regardless of gear. It was 55 degrees, riding down Hwy 1. No freezing temps for water freezing in the hub. I removed the front tire to place my bike in the trunk on its side when my wife picked me up. Home 15 mins later, took the bike out and it’s all of a sudden working again; engaged and could hear the wheel turn (hub noise)

Since then, I’ve taken the bike out for 3 or 4 rides. The problem has not reoccurred. Ensured nothing was loose. Replaced the rear tire because it was time. Did NOTHING else.

I’ll send a note to Specialized to see if they’ve heard of this problem. Also plan to contact the bike shop I purchased the bike shop when they return for Xmas break. I have maybe 6000 miles on the bike in 11 months.

Thanks for everyone’s help!!

Ron

Calsun

If it was my bike I would replace the cassette with a new one. Having a cassette freewheel on a hill is a great way to get hurt. I had a 28T cog dish on me in the sierras and crashed and hit my knee hard on the curbing. Had a 14-26 tooth freewheel for the remainder of my trip with the injured knee.

cxwrench

Why do you think replacing the cassette will make any difference in this case?

Calsun

Freewheel hub is what I meant. Terminology has deteriorated over time with regard to these components. One can take apart the entire assembly and check the pawls but I would not want to have my bike out of service while I did this. In addition not everyone has a bench vise and the tools needed to remove the assembly from the wheel hub.

Problems with braking or with a chain breaking apart or jambing in the chainring or a freewheel hub's pawls not engaging are at a different level of concern when riding up hills.

cxwrench

What does a freewheel hub or how to remove a freewheel have to do w/ this thread?

Russ Roth

You mean the freehub body and the terminology has been around longer then I've been wrenching on bikes which I started around 92/93. Checking on the problem is about an hour's job, give or take how fast you move and worth the time to investigate, clean and relube to make sure the problem stays away.
I would agree with going over it to make sure the problem stays away.

PeteHski

DT Swiss had a recent recall on some of their latest high end 2021 hubs (Ratchet EXP system) leading to loss of drive exactly as described here. Would be worth checking what hubs Roval are using as they could well be DT Swiss internals. There's an article about it here on Cycling Tips and it does mention Roval as an OEM fitment of these hubs

https://cyclingtips.com/2021/05/dt-s...vice-bulletin/

Homebrew01

Could be covered under warranty