Pro SX/MX setup adjustments, chassis etc.

ProjecTMX
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ProjecTMX
So I'm just a spectator of the sport, grew up watching since I was little. So this question might come across rather basic but I just want to understand what the riders are talking about when they mention setup adjustments, specifically chassis. I understand the basics, clicker adjustments, fork height, sag. But when riders, mechanics, or commentators speak about chassis adjustments what exactly is being done from a technical stand point. I assume they are talking about engine mounting and ways to make the chassis flex differently or not at all. What are some of the ways riders/mechanics go about adjusting chassis and how does "said adjustment" specifically change the character of the bike?

Jon
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imoto34
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imoto34 1/28/2017 11:38am
1/28/2017 11:38am
They don't move the engine or do anything with the frame that would change the way it flex's. Those guy's you watch on TV show up to the track and for the most part don't have to do much of anything but small tweaks here and there. Oil levels/ air pressure/ tire changes and a click hear and there can make the difference in the riders confidence sometimes more then the actual physical change. Pro's have most all big changes done during testing and not at the race track.

And maybe for Bagget, some extra attention to the clutch tonight.
rubarb
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rubarb 1/28/2017 11:43am
1/28/2017 11:43am
imoto34 wrote:
They don't move the engine or do anything with the frame that would change the way it flex's. Those guy's you watch on TV show up...
They don't move the engine or do anything with the frame that would change the way it flex's. Those guy's you watch on TV show up to the track and for the most part don't have to do much of anything but small tweaks here and there. Oil levels/ air pressure/ tire changes and a click hear and there can make the difference in the riders confidence sometimes more then the actual physical change. Pro's have most all big changes done during testing and not at the race track.

And maybe for Bagget, some extra attention to the clutch tonight.
Doesn't appear you answered Jon's question...?
GregDVT
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GregDVT 1/28/2017 12:32pm
1/28/2017 12:32pm
Different motor mount materials, sometimes they will drill them out a bit. They also adjust footpeg height and subframe height for the smaller guys.
scott_nz 1/28/2017 12:39pm
1/28/2017 12:39pm
also add in Triple Clamp offsets, and internal suspension valving, linkage ratios,

as for how it changes the ride, its all about the rider feeling comfortable,

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imoto34
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imoto34 1/28/2017 1:32pm
1/28/2017 1:32pm
rubarb wrote:
Doesn't appear you answered Jon's question...?
Hard to do considering the question is how does "said adjustments" change the characteristics of the bike.

It would take many hours to actually explain how each of the small adjustments reflect on the track to someone that isn't familiar with actually riding moto and them understand it.

When the OP is watching races from the couch and hear's anything about changing bike setup, it is mostly all minor things like changing the suspension a click or two but the OP said he know's the basics like changing clickers. The large changes typically aren't happening at the race track.


I may have missed it, but it doesn't appear you answered Jon's question. Cool
motokiwi 1/28/2017 3:53pm
1/28/2017 3:53pm Edited Date/Time 1/28/2017 4:28pm
Things that may or may not be considered a chassis adjustment:


Adjusting the wheelbase by adjusting the chain back / forward as far as possible.

Gearing could be considered a chassis adjustment sometimes when they are not so concerned about the ratio but are trying to get the bike to handle better thru whoops etc.

The order they torque the engine mount bolts in can produce different handling.

It wouldn't surprise me if teams like ktm had heavier parts they could insert into the lower areas of the chassis (e.g linkage / fork stanchions / footpegs) to make up weight and lower the center of gravity.

Rigidity of the triple clamps.

Torque setting on the swing arm main pivot bolt.

Steering head tightness?

Different frames with different amounts of gusseting in different areas for more / less rigidity.



hillbilly
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hillbilly 1/28/2017 4:21pm
1/28/2017 4:21pm
Static sag and race sag is not like you setup a bike for outdoors. Least it wasn't before this generation of air and tech.

Run over stiff spring and make the bike not top out and jump the quad,landing wherever,ask RC. He never gave 2 shits where he landed.
BobPA
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BobPA 1/28/2017 4:37pm
1/28/2017 4:37pm
hillbilly wrote:
Static sag and race sag is not like you setup a bike for outdoors. Least it wasn't before this generation of air and tech. Run over...
Static sag and race sag is not like you setup a bike for outdoors. Least it wasn't before this generation of air and tech.

Run over stiff spring and make the bike not top out and jump the quad,landing wherever,ask RC. He never gave 2 shits where he landed.
Slightly off topic, but pertaining to your observation. Did you notice all the kids now try and scrub off jumps with no landing....for example gravity cavity. Ricky one was of the last who would just hold it wide and send it to the flats off anything. Now it is all about the scrub, when I bet a lot of the times holding it open and launching to the flat is faster.
hillbilly
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hillbilly 1/28/2017 4:50pm
1/28/2017 4:50pm
hillbilly wrote:
Static sag and race sag is not like you setup a bike for outdoors. Least it wasn't before this generation of air and tech. Run over...
Static sag and race sag is not like you setup a bike for outdoors. Least it wasn't before this generation of air and tech.

Run over stiff spring and make the bike not top out and jump the quad,landing wherever,ask RC. He never gave 2 shits where he landed.
BobPA wrote:
Slightly off topic, but pertaining to your observation. Did you notice all the kids now try and scrub off jumps with no landing....for example gravity cavity...
Slightly off topic, but pertaining to your observation. Did you notice all the kids now try and scrub off jumps with no landing....for example gravity cavity. Ricky one was of the last who would just hold it wide and send it to the flats off anything. Now it is all about the scrub, when I bet a lot of the times holding it open and launching to the flat is faster.
I was sitting in Atlanta the practice KW broke that femur. What they were doing was unreal. Watched RC case it ever way you could. Just a few did it in practice. It was not jumped in the night program.

KW tried to jump from a lower takeoff and started endo,landing the 1st quad on the front then lauching the next still on the front. Probably the worst crash I ever saw indoors.

And that was when RC had that honda all laid down,weird looking,but didn't care.
ProjecTMX
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ProjecTMX 1/28/2017 4:56pm
1/28/2017 4:56pm
motokiwi wrote:
Things that may or may not be considered a chassis adjustment: Adjusting the wheelbase by adjusting the chain back / forward as far as possible. Gearing...
Things that may or may not be considered a chassis adjustment:


Adjusting the wheelbase by adjusting the chain back / forward as far as possible.

Gearing could be considered a chassis adjustment sometimes when they are not so concerned about the ratio but are trying to get the bike to handle better thru whoops etc.

The order they torque the engine mount bolts in can produce different handling.

It wouldn't surprise me if teams like ktm had heavier parts they could insert into the lower areas of the chassis (e.g linkage / fork stanchions / footpegs) to make up weight and lower the center of gravity.

Rigidity of the triple clamps.

Torque setting on the swing arm main pivot bolt.

Steering head tightness?

Different frames with different amounts of gusseting in different areas for more / less rigidity.



Thats interesting on the different frames and gusseting. So that leads to why I asked this question. I hear about chassis adjustments pretty often and read about teams making chassis changes to get better results for the rider. So my question was based partly out of curiosity to what they're actually changing and also being under the impression that the bikes had to be as close to production as possible. So "adjustments" could be made as long as it was within the limits of the production frame. (Example: Using offset engine mounts to change engine angles for desired feedback but still maintaining production bolt holes.)

I figured asking this would help me better understand why certain riders have a harder time figuring out setup's and answer my own questions to why fantastic rider's like ET3 have such issues when jumping aboard new machines. Also curious how Roczen found such a great setup for the RMZ and seemed to carry that over to Honda. Because after watching him on both brands it appeared the bikes handled and performed the same way. But I guess this could be a riders style as well.

I'm sure this conversation could go down the rat hole of beyond technical and eventually lead to me trying to find a rules book to better understand what is allowed and whats not. But I appreciate you guys chiming in and dropping some knowledge on me.
motokiwi 1/28/2017 5:12pm
1/28/2017 5:12pm
ProjecTMX wrote:
Thats interesting on the different frames and gusseting. So that leads to why I asked this question. I hear about chassis adjustments pretty often and read...
Thats interesting on the different frames and gusseting. So that leads to why I asked this question. I hear about chassis adjustments pretty often and read about teams making chassis changes to get better results for the rider. So my question was based partly out of curiosity to what they're actually changing and also being under the impression that the bikes had to be as close to production as possible. So "adjustments" could be made as long as it was within the limits of the production frame. (Example: Using offset engine mounts to change engine angles for desired feedback but still maintaining production bolt holes.)

I figured asking this would help me better understand why certain riders have a harder time figuring out setup's and answer my own questions to why fantastic rider's like ET3 have such issues when jumping aboard new machines. Also curious how Roczen found such a great setup for the RMZ and seemed to carry that over to Honda. Because after watching him on both brands it appeared the bikes handled and performed the same way. But I guess this could be a riders style as well.

I'm sure this conversation could go down the rat hole of beyond technical and eventually lead to me trying to find a rules book to better understand what is allowed and whats not. But I appreciate you guys chiming in and dropping some knowledge on me.
My theory is: Tomac is just little tall to be a champion. But once he gets his bike set up for his height he can go faster than anyone. It seems to take 2 years to get his bike set up for his height...

Info from: https://2tallracing.com/about-2tall/facts/

Riders heights:


Ryan Villopoto (173cm/5’8″)
James Stewart (170cm/5’7″)
Ryan Dungey (178cm/5’10”)
Ken Roczen (170cm/5’7″)
Justin Barcia (175cm/5’9″)
Justin Brayton (178cm/5’10”)
Andrew Short (180cm/5’11”)
Brock Tickle (180cm/5’11”)
Josh Hill (180cm/5’11”)
Chad Reed (180cm/5’11”)
Weston Peick (180cm/5’11”)
Mike Alessi (170cm/5’7″)
Nick Wey (177cm/5’10)
Eli Tomac (175cm/5’9″)
Joshua Grant (175cm/5’9″)
Matt Georke (180cm/5’11”)
Ivan Tedesco (175cm/5’9″)
Chris Blose (173cm/5’8″)
Jake Weimer (170cm/5’7″)

– Average height of AMA 450 champions in the past decade:

2013: Ryan Villopoto (173cm/5’8″)
2012: Ryan Villopoto (173cm/5’8″)
2011: Ryan Villopoto (173cm/5’8″)
2010: Ryan Dungey (178cm/5’10”)
2009: James Stewart (170cm/5’7″)
2008: Chad Reed (180cm/5’11”)
2007: James Stewart (170cm/5’7″)
2006: James Stewart (170cm/5’7″)
2005: Ricky Carmichael (168cm/5’6″)
2004: Chad Reed (180cm/5’11”)
2003: Ricky Carmichael (168cm/5’6″)
ProjecTMX
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ProjecTMX 1/28/2017 9:24pm
1/28/2017 9:24pm
Seems ET3 got it all figured out tonight!

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