Bike climbs out of ruts

Braaaphole
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Spring, TX US
4/24/2018 2:03pm Edited Date/Time 4/28/2018 7:59pm
I've been on this KTM 350 for a couple of months now and I consistently struggle to keep the bike in a rut. It seems like the front end always wants to climb up and out of the rut. Sometimes I get it right and can hammer on the throttle, but most of the time not so.
I don't know if this is a setup issue or technique, but it's an issue I didn't really have on previous bikes. Suspension is all stock AER forks and shock. I changed the rear spring to get it right for my weight. Sag is at 100mm and I can't get it down to 105, seems I went just a touch too stiff on the spring. Forks are raised to the 2nd line.
That said, rear end 5mm high shouldn't cause it to climb up out of the ruts. I'd expect that to transfer more weight to the front wheel and keep it planted in the rut a little better.
I'm considering raising the forks a couple of mm in the clamps to see if that helps. Any other suggestions?
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SoCalMX70
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4/24/2018 2:19pm
As a lifelong slow guy who's been spending a lot of time working on ruts lately... Try getting really far forward. Then try getting further back in the same turn. Try both a couple times, see what happens. You can adjust your setup based on which way felt better and get yourself back to a more comfortable position.

5mm sag can certainly make a difference. I'm on a completely different bike (YZ250), but I find the magical 100mm to not work for me at all. 105 and even 108mm feels great in all corners, berms and ruts alike... And YZs aren't known for their cornering prowess. Yes, more sag seemingly makes no sense for the front end climbing out, but it worked for me!

Maybe it has something to do with the bike not settling well (in your case, too stiff a spring), I don't know. Suspension is voodoo magic to me, so I just try stuff one setting at a time, and continuously record my results.

Basically, if biasing the chassis setup to heavily weight the front wheel isn't working, try going against convention and see if you get results.
4/24/2018 2:28pm
Lightly drag the front brake. Just enough to put pressure on the caliper piston.
AJ565
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San Antonio, TX US
4/24/2018 2:35pm
Look into the Ride Engineering steering stabilizer that uses the Showa unit from a Honda. It helped a lot on my '18 KTM.
slipdog
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Nor Cal, CA US
4/24/2018 3:10pm
What are your fork pressures and spring rate?

The Shop

MxKing809
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Fantasy
158th
4/24/2018 3:49pm
Look farther ahead
KMC440
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4/24/2018 3:54pm
Applying too much throttle in a burst while in the rut?
Also it sounds like this isn't a problem you're having exiting corners, more on rutted up straights... ?
Forty
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Saint Paul, MN US
4/24/2018 3:55pm
Bring that outside elbow up. Bike will drop right into that rut.
Denn700
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Shreveport, LA US
4/24/2018 3:58pm
I had the same issue and bought a Pro Circuit link arm. I could run whatever sag I wanted and it helped in the turns.
Forty
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4/24/2018 4:00pm
Forty wrote:
Bring that outside elbow up. Bike will drop right into that rut.
Oh. Straight Ruts! Practice. Practice. Look past em and practice.
make1go
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BF
4/24/2018 4:04pm
could be as simple as your tyre not working for your style
Mia
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US
4/24/2018 4:31pm
Drag the front brake
Knoby
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Wichita, KS US
4/24/2018 4:45pm
All good advice and pretty much what I learned from watching Semicks' videos. It's all about technique - look ahead, weight forward, elbow up, drag the brake if you have to, throttle out
jchek779
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San Juan Capistrano, CA US
4/24/2018 5:18pm
Slow down the rebound.
rjw141
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Fantasy
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4/24/2018 5:19pm
Lightly drag the front brake. Just enough to put pressure on the caliper piston.
This will help tons in my experience^^
Braaaphole
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Spring, TX US
4/24/2018 5:28pm
All good info, appreciate the replies. Just to clarify, it's in the corners I'm having the issue.
I'm running 156 psi in the forks and the shock spring is 5.2. I'm 215lbs and the suspension feels really good to me. A little harsh up front in a lot of chop, but that's just a trait of the AER forks from what I understand.

I have a race this weekend, so it will be difficult to go out and try different techniques but I'll see what I can get in during practice.
kkawboy14
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4/24/2018 5:35pm
Head more forward along with the front brake.....it can only wheelie if your to far back!
skypig
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Caloundra AU
4/24/2018 5:39pm
If you “can’t get 105mm sag”. I’d suggest the spring might be more than a little stiff. What static sag figure are you running?
The relationship between the two figures is a good indication of spring suitability.

If you have little to no preload, or your static sag is more than 40mm your spring is too stiff.

Might not be what is causing the subject concern however.

I’m crap in ruts because I’m old, terrified and unskilled. (But my suspension is perfect, and sprocket bolts torqued.)
KurtJ99
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Fantasy
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4/24/2018 5:40pm
I have more problems in left turns that right turns in ruts which make no sense. But same general issues with sag and setup. Tires don't really make a difference. It's all about settling in. I've messed with difference fork springs, shock springs, sag, fork heights. Fork heights seem to make little difference. Springs and sag make all the difference and it's what I mess with the most. Dragging the front brake a little helps.
c0ncEpT
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4/24/2018 6:42pm
MxKing809 wrote:
Look farther ahead
Agreed 100%.

Camp332
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Zoo Jersey US
4/24/2018 7:37pm
All quality advice here fellas. It hasnt been mentioned yet, so I would always increase my bench press, as a result I could push down harder on the bars bro.
Paw Paw 271
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Benton, LA US
4/24/2018 8:03pm
Change the rear spring to get the correct sag numbers.

Paw Paw
SoCalMX70
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Thousand Oaks, CA US
4/24/2018 8:07pm
The other thing I thought I'd mention is rebound... If it's too fast in either/both ends you can forget about the bike wanting to settle in. My uneducated guess would be that along with the shock spring being too stiff (again, related to not letting the bike settle in).

For the forks, you can start going in/stiffer on the rebound until it feels like its actually knifing inward/inside the rut, then back it out a bit. Obviously this may screw with how your bike handles other obstacles and you'll have to find a happy medium, but it's something to try.
dv12.com
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4/24/2018 8:14pm
Lightly drag the front brake. Just enough to put pressure on the caliper piston.
Like he said...
SoCalMX70
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4/24/2018 8:16pm
Well, doesn't get anymore knowing than that ^
Piston Slap
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4/24/2018 8:35pm
dv12.com wrote:
Like he said...
This guy would know best of all. . :-)
Meister
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Canton, OH US
4/24/2018 8:47pm
I battled this bad on my 14 yz 450. Both ends wanted to. My findings we're my forks rebound was too fast and springs too soft. I was low in the stroke and rebound was really not letting it settle that far down in the stroke.. The rear was completely related to the stock tire. I got rid of the 120 n went back to a trusty 110 and it sat right down in the ruts perfectly.

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