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My cup runneth over
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Picked up a Turner 2005 product guide yesterday and was drooling over it this morning - BUT what's with the upside down placement of the RP3 on the Nitrous? Ruins the picture! Maybe it's necessary? Plus what's with the asymmetrical chainstay design? Never seen anything like it! I think there was some comment on it here last summer but never saw an answer.

The DHR picture shows it equipped with a Romic but the text blurb talks only about the DHX - odd!

Still going to cut it all up and pin to my wall!
 

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Bodhisattva
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Technically, the RP3 is mounted correctly on the nitrous and all the others are upside down. The theory is that the shaft end is lighter and thus offers less mass and resistance than the canister end. I have no idea if this translates to anything on the trail, but that's the theory.
 

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rmac said:
Plus what's with the asymmetrical chainstay design? Never seen anything like it! I think there was some comment on it here last summer but never saw an answer.
Foes uses it on their frames. I believe the reason is for increased stiffness and tire clearance.
 

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Technology is my friend.
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But this Nitrous is "right side up".

The Squeaky Wheel said:
Technically, the RP3 is mounted correctly on the nitrous and all the others are upside down. The theory is that the shaft end is lighter and thus offers less mass and resistance than the canister end. I have no idea if this translates to anything on the trail, but that's the theory.
On the other hand, it is interesting to note that Henry Horrock's Nitrous has the RP3 mounted conventionally, like every other bike. See the picture Larry posted yesterday:
http://forums.mtbr.com/showpost.php?p=855502&postcount=59
So, did it come from Turner that way, indicating they changed their minds, or did Larry flip it around?

While I see where mounting with the piston shaft up would reduce the mass of the parts that move when the suspension is active, the effect would seem to be minuscule. And it seems to me that mounting it that way would make it more prone to water seeping in.
 

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I don't do PC
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Roy said:
Foes uses it on their frames. I believe the reason is for increased stiffness and tire clearance.
I think it's for weight savings, Foes doesn't use an asymetrical chainstay but they do use a 68mm shell and manipulate the tubing down there for added stiffness. Here's a good shot of my FXR
 

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Bodhisattva
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The effect of shaft up or canister up is likely miniscule. However, if you're going for maximum performance, then the proper way to do it is shaft up.
I'm planning on thrashing Henry's new Nitrous shortly ;)
 

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Technology is my friend.
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Yeah, but who flipped it?

The Squeaky Wheel said:
The effect of shaft up or canister up is likely miniscule. However, if you're going for maximum performance, then the proper way to do it is shaft up.
I'm planning on thrashing Henry's new Nitrous shortly ;)
Your Honor, please instruct the witness to answer the question! :)

But Henry's is clearly mounted shaft down in the picture. So who did the deed? Larry, or Turner, and was it intentional?
 

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Bodhisattva
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I wasn't there when the Nitrous arrived & I didn't think to ask Henry since I don't think it matters all that much.
I suspect it came from Turner that way.
If you really want to know I can ask Henry next time I see him.
 

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No, that's not phonetic
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The remote canisters were not available for the DHR's DHX at the time of the catalog shoot, therefore the Romic in the pic.

Without milling a valve notch in the Nitrous rocker, you have to run the shock "backwards" and so "upsidedown" may have seemed preferable. Also the RP3 has a pretty fat head and it may have made contact with early/prototype Nitrous rockers (speculation) which is something they would have cleared up by production.

A LOT of bikes have asym stays. The only reason for a dropped drive-side stay (really the chainstay yoke) is for front der clearance. That's it. There is no f der on the other side so a straight run eliminates some material so saves weigh and is stiffer. Machining asym yokes (slanted, not like the FXR) would be too expensive but bikes using welded yokes can come up with any shape they want including asym (like on Kona, Yeti, et al.).
 

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The assymetrical stays have to do with clearance. On the non-drive side, the lightest, stiffest design is a straight line. On the drive side, the stay needs to be bent for chainring and tire clearance. Why do some companies use symetrical rear ends? Because it's a lot easier to make them the same.

As for the shock orientation: Mounting it so the res is stationary has always been the rule on big bikes. I'm not sure why it isn't on short travel bikes with air shocks. Asthetics perhaps?
 

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Yup

Thanks to the forum for the answers. DHX was quite special, and late. The Proto Nitrous rockers were not relieved for the air valve (dunno where that brain fart came from) . But the production shocks are placed as they are for easy access to the lever. Same for Flux and
Spot. The shock is under pressure so keeping the piston in the oil bath like motos of old is not an issue. Un sprung weight could be added to the mix but with a shock that weights close to nothing and has such a short range of movement, it's a moot point.
Big bikes are subjected to higher everything and they are much heavier so I try and take that into consideration. The lost puppy is the RFX Pack, (big change for 2006) RETURN OF THE RFX!!!! in name only) Seems to have been a stupid marketing move of confusion to re-name a perfectly well named bike. Anyway the shock on it is body up and the resy is subjected to moremovement.It has always been that way and if the resy was more swept I could flip it. But it's not, so I can't. Uhhhhh I quess I could say that the trail muck more easily falls away from the wiper making the seals last longer, yeah that's the ticket.

DT
 

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Back to Work

turnerbikes said:
Thanks to the forum for the answers. DHX was quite special, and late. The Proto Nitrous rockers were not relieved for the air valve (dunno where that brain fart came from) . But the production shocks are placed as they are for easy access to the lever. Same for Flux and
Spot. The shock is under pressure so keeping the piston in the oil bath like motos of old is not an issue. Un sprung weight could be added to the mix but with a shock that weights close to nothing and has such a short range of movement, it's a moot point.
Big bikes are subjected to higher everything and they are much heavier so I try and take that into consideration. The lost puppy is the RFX Pack, (big change for 2006) RETURN OF THE RFX!!!! in name only) Seems to have been a stupid marketing move of confusion to re-name a perfectly well named bike. Anyway the shock on it is body up and the resy is subjected to moremovement.It has always been that way and if the resy was more swept I could flip it. But it's not, so I can't. Uhhhhh I quess I could say that the trail muck more easily falls away from the wiper making the seals last longer, yeah that's the ticket.

DT
Yeah, yeah, yeah. Never mind all this shock mounting trivia. Get back to work bringing the Highline to market!

Soon!

:) :) :) :)
 
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