Let’s talk WP Aer 48 Fork

Edited Date/Time 5/9/2020 10:44am
I bought a 2019 Ktm 350 sxf. Super fun bike and I get more comfortable on it with each ride. I’m about 180 lbs C rider. I am struggling to find Confidence in the corners with this bike, the front end seems to want to dance around. I’ve been messing with air pressure and lower pressure seems to help. The bike is amazing in choppy areas as it soaks everything up and feels great. Any setup advice or settings that have worked well for you?
|
NeedMoto
Posts
700
Joined
8/6/2015
Location
Lincoln, CA US
5/7/2020 9:30am
I just bought a 2020 FC 350 a couple weeks ago. 183 pounds, about the same speed. Initially my front end was vague, not very planted. Once I started dialing in the balance, playing with the shock settings, it is now great!

I ended up with 1 turn out on high speed comp on the shock, 104 sag. 15 out on compression, 13 out on rebound.

Forks 148 psi, 14 out on comp, 11 out on rebound.

One of our tracks has a couple of high speed 4th gear sections with some chop near the end and starts making slight dog leg. Several other buddies mostly complain about wicked head shake near the end of that straight. They all have steering dampers and still can't calm there bikes down. They just need to experiment more on there settings.

My bike get's through it with zero head shake. My buddies rode mine, and commented same thing, no head shake.

Absolutely love this bike, and that's coming off of a 19 KX450.
5
2
Hammer 663s
Posts
2321
Joined
6/2/2016
Location
Forest Grove, OR US
5/7/2020 9:41am Edited Date/Time 5/7/2020 9:42am
I bought a 2019 Ktm 350 sxf. Super fun bike and I get more comfortable on it with each ride. I’m about 180 lbs C rider...
I bought a 2019 Ktm 350 sxf. Super fun bike and I get more comfortable on it with each ride. I’m about 180 lbs C rider. I am struggling to find Confidence in the corners with this bike, the front end seems to want to dance around. I’ve been messing with air pressure and lower pressure seems to help. The bike is amazing in choppy areas as it soaks everything up and feels great. Any setup advice or settings that have worked well for you?
Multiple threads on this in Tech Help. Some guys seem to find settings that work, some of us couldn't. Many options to address depending on your budget.

https://www.vitalmx.com/forums/Tech-Help-Race-Shop,42/AER-conversion-mx…

https://www.vitalmx.com/forums/Tech-Help-Race-Shop,42/Advice-Needed-AER…

https://www.vitalmx.com/forums/Tech-Help-Race-Shop,42/19-ktm-150sx-tech…

Hammer

1
AJ565
Posts
2081
Joined
3/12/2012
Location
San Antonio, TX US
5/7/2020 10:16am
Some of your problem might be the rear spring. At 180 I think your a little heavy for the stock spring. If I remember right it comes with a 4.3 and at your weight you should be a 4.7 per racetech's site. Getting the shock right will help it hold the rear up and get more weight on the front end which will help your issue.
3
tek14
Posts
4592
Joined
1/26/2014
Location
Vantaa FI
5/7/2020 10:22am
Stiffer rear spring and slow down rebound in AER forks.
2
1

The Shop

Brent
Posts
5308
Joined
8/16/2006
Location
Party in Temecula, CA US
5/7/2020 11:34am





This is the best thing I have ever done for my KTM 350 . I cannot express to you how much difference a modified AER fork makes to front end stability. Kreft and Jeremy Wilkey are both offering similar mods.

You weigh the same as me, and I found the 45NM shock spring helps hold my fat ass up better, the bike corners far better than it did with the stock 42 Nm spring.
1
Hammer 663s
Posts
2321
Joined
6/2/2016
Location
Forest Grove, OR US
5/7/2020 12:05pm
Brent wrote:
[img]https://p.vitalmx.com/photos/forums/2020/05/07/425781/s1200_IMG_0470.jpg[/img] [img]https://p.vitalmx.com/photos/forums/2020/05/07/425782/s1200_IMG_0471.jpg[/img] This is the best thing I have ever done for my KTM 350 . I cannot express to you how much difference a modified...





This is the best thing I have ever done for my KTM 350 . I cannot express to you how much difference a modified AER fork makes to front end stability. Kreft and Jeremy Wilkey are both offering similar mods.

You weigh the same as me, and I found the 45NM shock spring helps hold my fat ass up better, the bike corners far better than it did with the stock 42 Nm spring.
What are you all in $$$ on the Kreft? All in on the Lucky Gen 1 I was about $2k shipped.

Hammer
1
5/7/2020 12:15pm
Brent wrote:
[img]https://p.vitalmx.com/photos/forums/2020/05/07/425781/s1200_IMG_0470.jpg[/img] [img]https://p.vitalmx.com/photos/forums/2020/05/07/425782/s1200_IMG_0471.jpg[/img] This is the best thing I have ever done for my KTM 350 . I cannot express to you how much difference a modified...





This is the best thing I have ever done for my KTM 350 . I cannot express to you how much difference a modified AER fork makes to front end stability. Kreft and Jeremy Wilkey are both offering similar mods.

You weigh the same as me, and I found the 45NM shock spring helps hold my fat ass up better, the bike corners far better than it did with the stock 42 Nm spring.
What are you all in $$$ on the Kreft? All in on the Lucky Gen 1 I was about $2k shipped.

Hammer
I went all in and it was about $1,900 after shipping, but I had to get a new spring, added the xtrig, and got the microfinish.

Cutting those item out would bring it down to $1,450 shipped.
Hammer 663s
Posts
2321
Joined
6/2/2016
Location
Forest Grove, OR US
5/7/2020 12:23pm
I went all in and it was about $1,900 after shipping, but I had to get a new spring, added the xtrig, and got the microfinish...
I went all in and it was about $1,900 after shipping, but I had to get a new spring, added the xtrig, and got the microfinish.

Cutting those item out would bring it down to $1,450 shipped.
And that's an AER air fork, right? Not a coil/oil conversion? I looked hard at this but chose MX Tech in the end,

Mike
austin_bo
Posts
549
Joined
12/1/2018
Location
Medford, NJ US
Fantasy
228th
5/7/2020 12:23pm
I think the manual recommends 155 lbs of pressure in the forks, but don't be afraid to go lower. I'm about 170 or so with gear on and was running around 150 lbs. I took a riding lesson with a pro and he commented that the bike kept standing up on me in the corners. I told him what air pressure I was running and he said that was way to high. He was around 180 and said he ran 138 lbs of pressure. I went down to the same and never looked back. I'm 18 clicks out on compression and like the rebound at the stock setting. Also went 1 3/4 turns out on high speed compression on the rear, and around 17 clicks on low speed. As long as you have the stock settings in the manual to revert back to, don't be afraid to go crazy. Just make sure you change one thing at a time so that you realize what you're adjusting.
5/7/2020 1:14pm
as you didnt mention it and i assume you might not have ignore all the info above and first check you sag
Brent
Posts
5308
Joined
8/16/2006
Location
Party in Temecula, CA US
5/7/2020 1:24pm
Brent wrote:
[img]https://p.vitalmx.com/photos/forums/2020/05/07/425781/s1200_IMG_0470.jpg[/img] [img]https://p.vitalmx.com/photos/forums/2020/05/07/425782/s1200_IMG_0471.jpg[/img] This is the best thing I have ever done for my KTM 350 . I cannot express to you how much difference a modified...





This is the best thing I have ever done for my KTM 350 . I cannot express to you how much difference a modified AER fork makes to front end stability. Kreft and Jeremy Wilkey are both offering similar mods.

You weigh the same as me, and I found the 45NM shock spring helps hold my fat ass up better, the bike corners far better than it did with the stock 42 Nm spring.
What are you all in $$$ on the Kreft? All in on the Lucky Gen 1 I was about $2k shipped.

Hammer
1915.00 for everything, I supplied a new 45Nm spring.

You can save a couple hundred of you don't do the mircofinishing, but I figured why not get the whole package.

I'm glad I did, this is the closest to Factory suspension that I'll ever get to.
5/7/2020 1:28pm
NeedMoto wrote:
I just bought a 2020 FC 350 a couple weeks ago. 183 pounds, about the same speed. Initially my front end was vague, not very planted...
I just bought a 2020 FC 350 a couple weeks ago. 183 pounds, about the same speed. Initially my front end was vague, not very planted. Once I started dialing in the balance, playing with the shock settings, it is now great!

I ended up with 1 turn out on high speed comp on the shock, 104 sag. 15 out on compression, 13 out on rebound.

Forks 148 psi, 14 out on comp, 11 out on rebound.

One of our tracks has a couple of high speed 4th gear sections with some chop near the end and starts making slight dog leg. Several other buddies mostly complain about wicked head shake near the end of that straight. They all have steering dampers and still can't calm there bikes down. They just need to experiment more on there settings.

My bike get's through it with zero head shake. My buddies rode mine, and commented same thing, no head shake.

Absolutely love this bike, and that's coming off of a 19 KX450.
For those of us thinking of going to 350 from 450, what is your feedback? Some say a 450 is easier to ride because you can be more lazy, and some are saying a 350 is easier to ride.
Brent
Posts
5308
Joined
8/16/2006
Location
Party in Temecula, CA US
5/7/2020 1:51pm
For those of us thinking of going to 350 from 450, what is your feedback? Some say a 450 is easier to ride because you can...
For those of us thinking of going to 350 from 450, what is your feedback? Some say a 450 is easier to ride because you can be more lazy, and some are saying a 350 is easier to ride.
I'm lucky enough to own both a 19 450 SXF and the 18 350 SXF.

I love both bikes, but they use different riding styles. If you like to lug the bike and short shift, then the 450 is for you, but you can feel the centrifical force of the motor in the turns more than the 350.

Even though there is only 1 LB of difference, it feels like it is more when you ride the 450.

If you like to rev it out and like a light feeling 250 style bike, then the 350 is the choice. I ride the 350 more than the 450 because I like the light feeling, although I miss the low end of the 450 in slow corners.

The 350 makes almost as much HP as the 450, but only in the upper range of RPM.

I know on rough tracks like Glen Helen, the 450 wears my ass out pretty quickly, the 350 I can ride a lot longer, and it is a lot more fun to ride.

If you watch Cole Seely's YouTube comparison video between the 350 and 450, listen to his RPM's on both bikes.

I am very interested in trying the Vortex ignition for the 350, if it gives me some more low end for the 350, then it would be the perfect bike for me.
2
crc245
Posts
1089
Joined
10/29/2007
Location
Yorba Linda, CA US
5/7/2020 2:12pm
I bought a 2019 Ktm 350 sxf. Super fun bike and I get more comfortable on it with each ride. I’m about 180 lbs C rider...
I bought a 2019 Ktm 350 sxf. Super fun bike and I get more comfortable on it with each ride. I’m about 180 lbs C rider. I am struggling to find Confidence in the corners with this bike, the front end seems to want to dance around. I’ve been messing with air pressure and lower pressure seems to help. The bike is amazing in choppy areas as it soaks everything up and feels great. Any setup advice or settings that have worked well for you?
Get a baseline PSI, set it, and forget it. Then, play with your clickers (like everyone does with "normal" spring forks). Wouldn't be surprised if you end up about 140-144lbs, 20-24 comp, 10-14 out on your rebound. AER are also sensitive to fork height changes, so that's a tuning option as well. Also, 13.5/14PSI in that stock MX3S usually works better than 12-12.5PSI.

On the shock: If you're at 100-105mm for sag, don't forget to check your free-sag number (this will let you know if a stiffer spring is in order). In on the HS also helped keep the 19' from G-ing out, which also keeps more weight on the front of the bike.


Once you get it sorted, should handle quite well. Enjoy!
5/7/2020 3:19pm
I had a similar issue with a 19.5 FC450, still sorting with clickers here and there, but I will say having the correct rear spring for my weight/speed set at 103mm of sag made a huge improvement. I also went in on HS comp on shock, bike still stable and the vaugeness I used to experience tracking through a rut was decreased a lot.

I came off riding KYB SSS for better part of 9+ years, so has been a major adjustment, though I enjoy that chassis a lot more than I did on my previous YZ250s that felt wooden in comparison.
1
5/7/2020 11:17pm
mxa and some vitards hated air forks. But then ktm got air forks! Now, these guys like the air fork? How convenient. I guarantee you, once ktm gets an aluminum frame, and they will, mxa will say well now the aluminum frame is the best and steel sucked. Watch
6
kkawboy14
Posts
11494
Joined
6/5/2015
Location
TX US
5/8/2020 3:29am
mxa and some vitards hated air forks. But then ktm got air forks! Now, these guys like the air fork? How convenient. I guarantee you, once...
mxa and some vitards hated air forks. But then ktm got air forks! Now, these guys like the air fork? How convenient. I guarantee you, once ktm gets an aluminum frame, and they will, mxa will say well now the aluminum frame is the best and steel sucked. Watch
I loved air forks!
1
erik_94COBRA
Posts
951
Joined
7/21/2016
Location
Houston-ish, TX US
5/8/2020 4:40am
Have a 19 Husky FC350. After Enzo revalved front and rear it’s working very good. The only minor complaint now is that the air forks don’t offer quite the same level of front end feel/grip, and the confidence to go with it. Revalve was under $500.

Lots of spring fork options if corner feel is really missing for you.
GoldenKTM
Posts
165
Joined
1/29/2017
Location
WI US
5/8/2020 4:54am
I felt the same thing with my 2017 250 SX and played with air pressure and it got a little better but in the end I bought a race tech spring conversion that was re-valved for my weight and its a much better fork now. If you have the money its worth spending.

Waiting patiently for the day ktm goes back to spring forks.
1
JB 19
Posts
4205
Joined
3/8/2009
Location
Marion, OH US
5/8/2020 5:49am
I just bought a 2019 350 SXF. I've done a lot of experimenting with the set up and there is a very wide range that these forks and even the shock will work in. I'm 145 pounds and a vet A level rider. For moto so far I have found that 144 psi 22 out on compression and 14 out on rebound works pretty good. For me more air and opened up compression clickers were better. Too little air made them rigid in braking bumps.

I also did quite a bit of testing in off road woods since that's mostly what I race these days. 135 psi and comp and rebound opened almost all the way up really allowed them to settle and conform to the terrain in the woods.

The thing I like about the AER forks is that I think I can set them up for moto or off road racing. They have a huge range of workability, but you have to make drastic changes with the clickers and air to see what they are capable of.
1
1
mark_swart
Posts
2410
Joined
11/2/2011
Location
Chapin, SC US
5/8/2020 7:48am
I'm a +40 B rider and have been pretty happy with my AERs on my 17.5 FE 450. I run the air pressure in the 142-146 range depending on the track and conditions. The stock pressure is way too stiff for most riders. I'd say double check sag and experiment with the air pressure before you start spending money.
mx510
Posts
1974
Joined
2/26/2011
Location
Gig Harbor, WA US
Fantasy
1707th
5/8/2020 10:21am
Dancing around? Have you tried tightening up the stem nut a little bit?
1
TeamGreen
Posts
29092
Joined
11/25/2008
Location
Thru-out, CA US
5/8/2020 11:07am
mxa and some vitards hated air forks. But then ktm got air forks! Now, these guys like the air fork? How convenient. I guarantee you, once...
mxa and some vitards hated air forks. But then ktm got air forks! Now, these guys like the air fork? How convenient. I guarantee you, once ktm gets an aluminum frame, and they will, mxa will say well now the aluminum frame is the best and steel sucked. Watch
kkawboy14 wrote:
I loved air forks!
I have a set of PC valved SF1s that are superb.
RCF
Posts
546
Joined
4/1/2008
Location
PA US
5/8/2020 1:20pm
I just fixed my kids air forks.

1
TeamGreen
Posts
29092
Joined
11/25/2008
Location
Thru-out, CA US
5/8/2020 1:22pm
RCF wrote:
I just fixed my kids air forks. [img]https://p.vitalmx.com/photos/forums/2020/05/08/425968/s1200_0508201131a.jpg[/img]
I just fixed my kids air forks.

Do you adopt 50sumthins?
4
Tuna
Posts
1582
Joined
4/3/2017
Location
CA
5/8/2020 1:49pm
RCF wrote:
I just fixed my kids air forks. [img]https://p.vitalmx.com/photos/forums/2020/05/08/425968/s1200_0508201131a.jpg[/img]
I just fixed my kids air forks.

Lucky kid. Not everyone has the kind of money to do that.
1
1
Hammer 663s
Posts
2321
Joined
6/2/2016
Location
Forest Grove, OR US
5/8/2020 1:54pm
RCF wrote:
I just fixed my kids air forks. [img]https://p.vitalmx.com/photos/forums/2020/05/08/425968/s1200_0508201131a.jpg[/img]
I just fixed my kids air forks.

I read someone that indicated the Ohlins are too flexy with the steel chassis. He felt that they'd been designed with an alu chassis in mind, not steel, so the flex was setup differently. So he preferred to stay with the WP tubes and convert as that didn't change the flex characteristics. But what do I know. I'm too slow probably to notice any difference.
TeamGreen
Posts
29092
Joined
11/25/2008
Location
Thru-out, CA US
5/8/2020 2:17pm
RCF wrote:
I just fixed my kids air forks. [img]https://p.vitalmx.com/photos/forums/2020/05/08/425968/s1200_0508201131a.jpg[/img]
I just fixed my kids air forks.

Tuna wrote:
Lucky kid. Not everyone has the kind of money to do that.
Aren't Ohlins pretty fairly priced?
RCF
Posts
546
Joined
4/1/2008
Location
PA US
5/8/2020 2:21pm Edited Date/Time 5/8/2020 2:33pm
RCF wrote:
I just fixed my kids air forks. [img]https://p.vitalmx.com/photos/forums/2020/05/08/425968/s1200_0508201131a.jpg[/img]
I just fixed my kids air forks.

Tuna wrote:
Lucky kid. Not everyone has the kind of money to do that.
TeamGreen wrote:
Aren't Ohlins pretty fairly priced?
I got a little lucky I guess ohlins had a sale Dean Burke still had two sets of the reduce priced Forks left, I believe normally there 3300. I have a flow shock coming to and he revalves them for free.
1
Tuna
Posts
1582
Joined
4/3/2017
Location
CA
5/8/2020 3:39pm
RCF wrote:
I just fixed my kids air forks. [img]https://p.vitalmx.com/photos/forums/2020/05/08/425968/s1200_0508201131a.jpg[/img]
I just fixed my kids air forks.

Tuna wrote:
Lucky kid. Not everyone has the kind of money to do that.
TeamGreen wrote:
Aren't Ohlins pretty fairly priced?
A lot cheaper in the US than Canada. Just the inserts here are $2k.
1

Post a reply to: Let’s talk WP Aer 48 Fork

The Latest