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Aer48 psi interesting data any input welcome

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Fork sags

09 yz450f 
60 race
28 static ( is on the soft side but very plush)

18 yz450f ( stock springs )
27 static 
42 race

Ktm aer  

147psi
30 static
58 race

157
30 static 
 51 race

163psi
27 static 
48 race

Racetechs recommended psi for my weight 166psi

Static 26
Race47

which falls close to the 18 yz450f fork sag numbers, now is running the low pressures 145psi ect for the  450sxf loading up the rear and causing it to kick and now we are seeing all these aftermarket knuckles/ linkages ect coming into the market... would it be wise to run the higher pressure and valving the comp softer to suit?

ill will be testing this therory tomorrow

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Around 148psi is ok with 45nm, higher then that you need stiffer rear spring.

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I go on fork dive ,I adjust the pressure based on that ,then tune clickers for the rest

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Not sure whether I should ask here or start a new thread...

Just got a 2019 250SX with AER48 and the numbers you have posted here might explain my confusion last night when trying to set the sag. I always thought that fork sag should be the same as shock sag (~105mm). I had already set the pressure to what the manual suggested (75-85kg rider, I am 85kg) but the rider sag was nowhere near 105mm.

So, what should the rider sag be on the forks? I've had a look at the Racetech air pressure recommendations too, so maybe I should just go with those?

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You can't really do fork sag on an aer , the numbers don't really seem to compare to spring forks

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7 hours ago, mog said:

You can't really do fork sag on an aer , the numbers don't really seem to compare to spring forks

Thanks, so should I use the Racetech recommendation as a baseline to start from? 

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In the discussion on AER pressure and ride height you now have to keep in mind that the 2020 fork is going to have to run a higher pressure.

This is due to a softer pressure spring and smaller balance chamber volume. A step in the wrong direction to me.

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Thanks, so should I use the Racetech recommendation as a baseline to start from? 
Hard to say ,I use ktm settings and work from that , but my fork is still totally STD

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3 hours ago, mog said:

Hard to say ,I use ktm settings and work from that , but my fork is still totally STD

That will probably work ok for me as I am in the weight range for the PSI they recommend in the manual. My son is much lighter (he's on a 2018 250SX) so I'm also trying to find something that will work well for him. I'll just start with the Racetech recommendations and see how we go. I've already set the damping to "Standard" setting in the book. Once we've got some time on the bikes we'll try the "Sport" setting at the MX track, and probably the "Comfort" setting on the trails. Just want a baseline to start from for both MX and trails that isn't going to be completely shit.

Edited by pgalligan
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I think a serious thread needs to be started on this. Even when these forkes dive or bottom everything is so linear its hard to tell on the bike. Need pictures as im finding

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In order to get my TC250 to turn better I lowered air pressure from 153 all the way down to 125 psi, and I tried raising the forks in the clamps.  None of that helped it turn, but it did make the front end dive and feel skittish even on loose straight sections.  I ended up moving my bars forward and taking a link out of my chain to move the rear wheel forward.  It turns much better and I'm up at 147 psi again.  Racetech site says I should have 152 psi.

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To make it turn better, add rebound to the forks. Its pretty much what its for.

In order to get my TC250 to turn better I lowered air pressure from 153 all the way down to 125 psi, and I tried raising the forks in the clamps.  None of that helped it turn, but it did make the front end dive and feel skittish even on loose straight sections.  I ended up moving my bars forward and taking a link out of my chain to move the rear wheel forward.  It turns much better and I'm up at 147 psi again.  Racetech site says I should have 152 psi.

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2 hours ago, hondaman331 said:

To make it turn better, add rebound to the forks. Its pretty much what its for.

Oversteer=not enough rebound

Understeer=too much rebound

That wasn't my problem though.  I tried that and oil level and rest sag too.

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Oversteer=not enough rebound
Understeer=too much rebound
That wasn't my problem though.  I tried that and oil level and rest sag too.
Hmm. Maybe got to find a sweet spot. I was always under the impression rebound will hold your forks down in the stroke, more makes it turn sharper, less makes it stay up in its stroke and understeer.

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2 hours ago, hondaman331 said:
9 hours ago, mxaniac said:
Oversteer=not enough rebound
Understeer=too much rebound
That wasn't my problem though.  I tried that and oil level and rest sag too.

Hmm. Maybe got to find a sweet spot. I was always under the impression rebound will hold your forks down in the stroke, more makes it turn sharper, less makes it stay up in its stroke and understeer.

I think the key here is if the term dampening is/should be in the sentence when you define rebound".

More rebound damping = lower in the stroke, easier to turn

More rebound interpreted as opening rebound up, or faster rebound= opposite

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I think the key here is if the term dampening is/should be in the sentence when you define rebound".



More rebound damping = lower in the stroke, easier to turn



More rebound interpreted as opening rebound up, or faster rebound= opposite
More rebound damping is turning dial clockwise, in. It slows the rebound. Less rebound damping is counterclockwise, out, and allows freer oil flow for the spring to spring versus be slowed down. I know no other way to think about that.

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1 hour ago, hondaman331 said:
1 hour ago, AEES said:



I think the key here is if the term dampening is/should be in the sentence when you define rebound".



More rebound damping = lower in the stroke, easier to turn



More rebound interpreted as opening rebound up, or faster rebound= opposite

Read more  

More rebound damping is turning dial clockwise, in. It slows the rebound. Less rebound damping is counterclockwise, out, and allows freer oil flow for the spring to spring versus be slowed down. I know no other way to think about that.

Absolutely, but a statement like "more rebound" can be interpreted as either "more (faster) rebound", or "more rebound damping". There is where the confusion often appear.

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