The "evils" of suspension bob

[thebob]

Not as evil as the industry would like us to believe! IMO lockouts are more useful for the rear to get it to sit up thereby minimising pedal strikes and steepening the seat tube angle for a slightly better seated climbing position.

 

Edited October 12, 2021 by thebob

[TheoG]

1 hour ago, thebob said:

Not as evil as the industry would like us to believe! IMO lockouts are more useful for the rear to get it to sit up thereby minimising pedal strikes and steepening the seat tube angle for a slightly better seated climbing position.

 

Regardless of what the research say, I will continue to use my lockout when doing serious climbing or riding on a tar road.  The mental thing of "how it feel" is a lot more important imho.

[thebob]

3 minutes ago, TheoG said:

Regardless of what the research say, I will continue to use my lockout when doing serious climbing or riding on a tar road.  The mental thing of "how it feel" is a lot more important imho.

Tar road climbing for sure. Locked out is much more comfy!

[Mamil]

Do we need a way to measure the total movement of the suspension when it's open versus total movement of the suspension over a climb when it's closed and if there's a difference between those then ask

"Where does the energy to move the suspension when open come from if not from the power output of the rider?"

[thebob]

Chain forces, braking forces, weight transfer, terrain to name a few. If suspension only moved cause of rider power output then explain DH bikes

[Delta Bikes]

When it comes to the tests, the first 2 he shows, they do not indicate speeds at all, at least I didn’t see any.

On his own test he did, he took the wattage on the cranks, which wouldn’t be accurate as the power loss isn’t in the drivetrain, it’s in the suspension, this power wouldn’t go through the cranks.

Not sure if he cleared any of this up, but I stopped watching there.

[Delta Bikes]

12 minutes ago, thebob said:

Chain forces, braking forces, weight transfer, terrain to name a few. If suspension only moved cause of rider power output then explain DH bikes

DH bikes aren’t for climbing.

Rider output isn’t the only factor, but on a flat climb it’s definitely a major factor.

[thebob]

I just went to the extreme example with a DH bike. I'm always blown away by how the local scene seems to vilify suspension movement whilst pedaling. It seems to me that the thinking hasn't moved on from the 90's when dual sus emerged and it was thought they would never be efficient enough for XC racing with pedal bob being pointed to as a major thief of watts. 

[Yyyy]

21 minutes ago, AkwA said:

When it comes to the tests, the first 2 he shows, they do not indicate speeds at all, at least I didn’t see any.

On his own test he did, he took the wattage on the cranks, which wouldn’t be accurate as the power loss isn’t in the drivetrain, it’s in the suspension, this power wouldn’t go through the cranks.

Not sure if he cleared any of this up, but I stopped watching there.

He does show time it took to cover the distance.

 

[ChrisF]

10 minutes ago, thebob said:

I just went to the extreme example with a DH bike. I'm always blown away by how the local scene seems to vilify suspension movement whilst pedaling. It seems to me that the thinking hasn't moved on from the 90's when dual sus emerged and it was thought they would never be efficient enough for XC racing with pedal bob being pointed to as a major thief of watts. 

 

I do believe SCOTT got it right with the "dual lockout" system. with THREE settings, i.e. Open, traction, locked.

 

Tar and smooth compacted gravel the "locked" setting just feels right.

 

The "traction" setting WORKS for uneven climbs.

 

Obviously "open" for having fun along the trails.

 

 

 

Disclaimer - this is based purely on "feel" over many rides including trails, gravel and tar. 

 

When going along smooth tar there is only ONE reason a bike "bobs", rider energy input .....

 

[Delta Bikes]

 

1 minute ago, YaseenEnos said:

He does show time it took to cover the distance.

 

Yes, but the way he measures the watts isn’t accurate as the loss isn’t in the drivetrain.

[Delta Bikes]

16 minutes ago, thebob said:

I just went to the extreme example with a DH bike. I'm always blown away by how the local scene seems to vilify suspension movement whilst pedaling. It seems to me that the thinking hasn't moved on from the 90's when dual sus emerged and it was thought they would never be efficient enough for XC racing with pedal bob being pointed to as a major thief of watts. 

Technology has come very far, modern forks and shocks are really good when it comes to loss through the suspension.

There is still a loss, the power to compress the fork/shock comes from somewhere and is mostly lost. Even if it comes from your body mass, this is still power lost. Think how it’s more difficult to climb stairs than walk on flat. It takes energy to lift your mass.

[TheoG]

28 minutes ago, ChrisF said:

 

I do believe SCOTT got it right with the "dual lockout" system. with THREE settings, i.e. Open, traction, locked.

 

Tar and smooth compacted gravel the "locked" setting just feels right.

 

The "traction" setting WORKS for uneven climbs.

 

Obviously "open" for having fun along the trails.

 

 

 

Disclaimer - this is based purely on "feel" over many rides including trails, gravel and tar. 

 

When going along smooth tar there is only ONE reason a bike "bobs", rider energy input .....

 

Its not a Scott thing, its a previous gen Fox thing, my Rocky Mountain also have it and the previous Bianchi Methanols also had it.

[DieselnDust]

ah the old youtube= science..

35 minutes ago, AkwA said:

 

Yes, but the way he measures the watts isn’t accurate as the loss isn’t in the drivetrain.

I think you're confusing rider power output vs how that translates to speed.

All he is suggesting is that the suspension in the open position doesn't add to the riders physiological load and this is true. There are many times I forget to firm up my suspension and just leave it open. It doesn't feel any slower and the Watts are the same as when the suspension is firmed. Standing and pedaling there is a noticeable difference in feel but not Watts.

If you want to measure power at the contact patch to determine if there is any power loss through the suspension and drivetrain then yu'd need a rolling road or chassis dynamometer.

 

but since forward speed on a flat road is unaffected I'd place my bets on Dylan's side of the fence. Where the lockout makes a huge difference is out of the saddle efforts like sprints and climbs. Limiting the slackening of the seat tube is also a benefit of lockout at the rear and a reason I prefer separate lockout devices for the front and rear of the bike

Edited October 12, 2021 by DieselnDust