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Npdh

Monkey
Apr 29, 2007
141
0
Running an air shock upside down on bikes like the Pitch ?

We couldn't have a good argue if (theory) there is a noticiable difference but i did felt them not quite similar on little tests around the block.

Does anyone know something about this ?
 

Npdh

Monkey
Apr 29, 2007
141
0
Running an air shock upside down on bikes like the Pitch ?

We couldn't have a good argue if (theory) there is a noticiable difference but i did felt them not quite similar on little tests around the block.

Does anyone know something about this ?


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tacubaya

Monkey
Dec 19, 2009
720
89
Mexico City
Upside down has less unsprung mass, but lettuce be cereal the difference must be minimum.

If you mount it normally you will have float fluid lubing the air seal constantly, dirt being pushed away from the seal and better reach of adjustment dials.
 

Npdh

Monkey
Apr 29, 2007
141
0
Upside down has less unsprung mass, but lettuce be cereal the difference must be minimum.

If you mount it normally you will have float fluid lubing the air seal constantly, dirt being pushed away from the seal and better reach of adjustment dials.
Yes. I did realize about the lubing , but the difference that i felt isn't about lubing or anything like that. It was more like a feeling of how the shock compress in both positions. On the upside down position i felt it like i had more control on how the shock bounced into the mid travel and reafirm this cornering on the bike. It did felt a lot difference from my point of view. Like that i could go on the travel without feeling the same return of the suspension.

Note: this is not a thread about the best position of the shock on the frame. It's just a quick question for understanding a little more about everything that affect suspension

My question is, is there something that i'm missing or is just physcologic
stuff...

Thanks !
 
Last edited:

Sandwich

Pig my fish!
Staff member
May 23, 2002
21,031
5,921
borcester rhymes
likely psychological...there shouldn't be any difference upside down or rightside up outside of lowered unsprung mass, which may be very slight, or better sealing and lubrication.

personally, I'd go for shock body-up, as it'll last longer/seal better/run smoother and unless you're going for all-out race performance, that's more valuable to me.
 

time-bomb

Monkey
May 2, 2008
957
21
right here -> .
As long as you run it vertically it shouldn't matter which end is up, you probably won't notice a difference either way. However, if you try to mount it horizontally, the results could be disastrous. ;)
 

Npdh

Monkey
Apr 29, 2007
141
0
Yeeah , then it must be just psychologic stuff. But ( i will try again today ) in the moment that i tried it it was for me a obvious difference. I'm not an engineer an i only
understand the basic concepts that affect suspension, so that's why i asked here.

I will do it again tho.

If anyone have a answer a little more on the mechanic side it could be great !!
 
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marshalolson

Turbo Monkey
May 25, 2006
1,770
519
Upside down has less unsprung mass, but lettuce be cereal the difference must be minimum.

If you mount it normally you will have float fluid lubing the air seal constantly, dirt being pushed away from the seal and better reach of adjustment dials.
going to say not true on the unsprung mass argument on an air shock without reservoir. all the damping is at the rebound/slider side, the air can is the lightest part. you want that at the top to minimize unsrpung mass. which also happens to be the way you want the shock oriented for seal protection and lubrication, and adjusting the compression knob.

so long story short, as pictured is wrong for every reason you could think of.
 

tacubaya

Monkey
Dec 19, 2009
720
89
Mexico City
going to say not true on the unsprung mass argument on an air shock without reservoir. all the damping is at the rebound/slider side, the air can is the lightest part. you want that at the top to minimize unsrpung mass. which also happens to be the way you want the shock oriented for seal protection and lubrication, and adjusting the compression knob.

so long story short, as pictured is wrong for every reason you could think of.
If you place it normally, the link must push an air canister, piston and all the dials through the oil. If you place it like in the picture posted, the linkage just pushes the shaft downwards while piston and other stuff remains static.

 

Kevin

Turbo Monkey
If you place it normally, the link must push an air canister, piston and all the dials through the oil. If you place it like in the picture posted, the linkage just pushes the shaft downwards while piston and other stuff remains static.

Ive allway wondered about this.
Isnt this just theoretic bs and even if it isnt so wouldnt you be able to make up for this with a fart less or more pre load? :s
 

tacubaya

Monkey
Dec 19, 2009
720
89
Mexico City
Ive allway wondered about this.
Isnt this just theoretic bs and even if it isnt so wouldnt you be able to make up for this with a fart more less or more pre load? :s
Yep, once you calculate the forces that the link applies to the shock you realize the unsprung mass shiat is retarded.

On forks it may be a different story tho..
 

Kevin

Turbo Monkey
Yep, once you calculate the forces that the link applies to the shock you realize the unsprung mass shiat is retarded.

On forks it may be a different story tho..
Why would it be different on forks?
You set up a fork the way it feels good and u adjust it acording to how it feels no matter how much the unsprung weight is.
The end result is the same on any fork or shock...

I might be confused but I would love to know if im missing something...
 

tacubaya

Monkey
Dec 19, 2009
720
89
Mexico City
Why would it be different on forks?
You set up a fork the way it feels good and u adjust it acording to how it feels no matter how much the unsprung weight is.
The end result is the same on any fork or shock...

I might be confused but I would love to know if im missing something...
Um yeah but.. examine this extreme scenario. You hit a bump with X force. According to Newton, the bump hits your wheel with force X as well. This force will try to move the wheel up. If the lowers are very heavy (remember, extreme scenario) the force X will not be able to move the lowers up in relation to the stanchions and no shaft speed, thereby no damping force, will be developed. This will result in the wheel just following the contour of the trail and the whole system (fork and handlebars) too. If the lowers are very light, the force will produce shaft movement, thereby damping and your hands will feel less feedback.