Road Bike, Cycling Forums banner

41 - 60 of 73 Posts

·
Banned Sock Puppet
Joined
·
13,595 Posts
Well that answers it then. It's up to 142 for disc rears. Would have been nice to use that for more gears back there instead of that disc brake. With that spacing I think they could have gone to 14 gears
14??? Do we really even need 11? Come on!
 

·
Banned Sock Puppet
Joined
·
13,595 Posts

·
Registered
Joined
·
52 Posts
14??? Do we really even need 11? Come on!
Well if we had 14 we could ditch the FD comfortably and have a nice gear range with smooth transitions. Also, we would use all of our gears and not waste any on gear overlaps such as in double and triple systems. Yet a better idea is the idea of using an internal gear in the rear hub that has two speeds and the 11 speed rear gear.

A company called Classified has developed a wireless internal two-speed rear hub. You still have your 11-speed drivetrain as well. Hopefully, this will be the new way to do it. Shifting between the two gears is in microseconds and can shift under load up to 1000 watts
 

·
Registered
Joined
·
4,872 Posts
What is your rpm shift points?
... and your 2 speed hub will have overlapping gears! Hello!
 

·
Registered
Joined
·
19,495 Posts
Well if we had 14 we could ditch the FD comfortably and have a nice gear range with smooth transitions. Also, we would use all of our gears and not waste any on gear overlaps such as in double and triple systems. Yet a better idea is the idea of using an internal gear in the rear hub that has two speeds and the 11 speed rear gear.

A company called Classified has developed a wireless internal two-speed rear hub. You still have your 11-speed drivetrain as well. Hopefully, this will be the new way to do it. Shifting between the two gears is in microseconds and can shift under load up to 1000 watts
I saw this recently. Definitely looks interesting. People have tried gearhub/gearboxes for years. But they're generally way too heavy, expensive, inefficient. This is a much simpler take on it. Just a 2 gear toggle.

 

·
Registered
Joined
·
635 Posts
I can’t imagine pros being ok with both the chain and derailleur inefficiency and now a planetary gear loss as well, and if pros won’t I won’t either. Then again maybe more efficient than a 1x11 drivetrain in the furthest cogs...but if you’re using this you’d have that inefficiency as well

The planetary gear has tiny and few teeth and will wear out

Hoping some team with all the old school tech from the 80s joins the tour and crushes all these nerds.
 

·
Registered
Joined
·
52 Posts
Actually their test have shown this internal gear to handle well at 1000watts of force. Much more than any front derailleur can withstand. The question I think would be weight, but then you can remove your front derailleur, front cable and housing and remove a front chainring so I think it is actually better for a pro. Also I recommend watching the GCN video on this it was very informative. The internal gear can be change under full load unlike what you really can’t do with a front changer. It currently seems designed to work best with bikes designed with rear disk brakes and the 142 mm axle. The battery is usb rechargeable and resides in the axle. They claim it last a week before needing recharging.
 

·
Registered
Joined
·
19,495 Posts
I can’t imagine pros being ok with both the chain and derailleur inefficiency and now a planetary gear loss as well, and if pros won’t I won’t either.
Except that is offset by a more straight chainline and the power loss from using smaller chain rings.

Throw in never dropping a chain. And faster front shifts, even under full load.

The planetary gear has tiny and few teeth and will wear out
Not true.

"The Classified hub has an operational lifespan exceeding the lifespan of a bicycle’s internal systems, and it requires no maintainance."
 

·
Registered
Joined
·
635 Posts
it will have the same chainline as 11x1 or any other single chainring front.

the power loss of using a 36 tooth chainring is less than a planetary gear.

i wouldnt trust a sales person telling how long their product lasts. theyre claiming it exceeds the lifespan of the the bicycle's "internal systems"...whatever that vagueness is.
What is the Life Expectancy of My Planetary Gear System? |Cleveland, OH (matexgears.com)


all the internal gear systems using planetary gears have friction and drag and this is no exception despite the hype. the gears hopefully are replaceable at a reasonable cost

  • "At commuter/recreational power levels, current hub gears are typically about 10% less efficient than reasonably maintained derailleur gears.[20][21] (note: some marketing material from tests performed by the manufacturers has the number at 2%, but that is not only false, but impossible. Several tests compared a new internal gear hub with an old and badly-maintained derailleur system, or did not apply any weight on the axle and load into the system. The real numbers are different - the efficiency/losses are closer to that of all planetary gear transmissions.)"
Hub gear - Wikipedia
 

·
Registered
Joined
·
19,495 Posts
that doesnt tell of the efficiency. there will be a loss in the planetary gears from friction.
How efficient is the hub?
Very efficient! More efficient than a 1x setup and as efficient as a 2x setup. Compared to a 1x, less cross chaining is required, sprocket and chainring sizes are larger and thus chain tension, crank and hub bearing losses are lower. Compared to a 2x; the fact that the 0.7 ratio of the hub still uses the large chainring in front, results in 30% less chain tension and thus lower chain, crank and hub bearing losses. On top of this you will experience that you will use the Classified hub much more frequent than a normal front derailleur, this means that in practice you will have less cross chain losses. The hub does not have any additional losses on in the 1:1 ratio, and is designed to have extremely low losses in the 0.7 ratio which are completely balanced out by the big chainring and straighter chainline by using a Classified setup.


With the Powershift hub, the fact that the planetary gear is only used for a single gear has a positive effect. The unused gears are then locked together and rotate as one. This is not possible with multi-gear hubs. Given this background, Classified promises an efficiency of 99 percent. This seems quite realistic, since there are no bearings or seals in the gearbox that could cause additional friction.
 

·
Registered
Joined
·
635 Posts
you want no seals and no friction and a lifespan forever. you want it all. you can believe them at 1% inefficiency but as i linked just above that's pretty much impossible. there's the reality of planetary gears and their friction.
i think i see 7 planetary gears!! and you think all of them spinning will be more efficient than a chain and chainring? is it a tiny bearing centered in each or is that just a bushing?
Efficiency of Planetary Gearsets (benchtophybrid.com)


479387


and when not engaged you essentially have to have another freewheel with its ratchets running across as well. im not saying it sucks..just saying youre not going to get 99% efficiency.
even a singlespeed bike isnt getting close to that Drivetrain Efficiency: What's The Difference In Speed Between 1X and 2X? - CyclingAbout

"
– The 1X drivetrain is as efficient as 96.0% and as inefficient as 92.4%. On average it’s 95.1% efficient.
– The 2X drivetrain is as efficient as 96.8% and as inefficient as 94.8%. On average it’s 96.2% efficient. "
and this gear hub does use a 1x setup and you still have the same inefficient chainline
 

·
Registered
Joined
·
19,495 Posts
You're comparing apples and oranges. This isn't that type of multi geared hub box.

so you want no seals and no friction and a lifespan forever. you want it all. you can say it's efficient but there's the reality of planetary gears and their friction.
It doesn't say no seals. That's silly. It says no bearings or seals IN the gearbox. You only need a seal on the outside.

Ridley bikes is already selling these on their bikes... but surely... you know what they don't.
 

·
Registered
Joined
·
635 Posts
You're comparing apples and oranges. This isn't that type of multi geared hub box.

It doesn't say no seals. That's silly. It says no bearings or seals IN the gearbox. You only need a seal on the outside.

Ridley bikes is already selling these on their bikes... but surely... you know what they don't.
a seal or no seal: you can have it clean or you can have no friction. they have it on the outside, ok, and you get what you get with that.
this is a planetary gear, that's what i linked. if you believe that the rest of the drivetrain with the derailleur and chainline are no longer a loss look again and see that theyre still in operation as well.

I know what Ridley dont? if they believe theyre getting 99% efficiency then yes i know what they dont.
 

·
Registered
Joined
·
19,495 Posts
a seal on the outside is a seal. that's friction.
You're just making up strawmen to argue against. Nobody said no friction. It said REDUCED friction from not having INTERNAL BEARINGS AND SEALS.
That is reduced friction from the type of gearbox you're pretending this is.



if you believe that the rest of the drivetrain with the derailleur and chainline are no longer a loss look again and see that theyre still in operation as well.
Nobody ever said or implied that. More strawmen.
 
41 - 60 of 73 Posts
Top