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KTM Nose diving on whoops

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        I have a 2002 ktm 200 exc with modified suspension. I weigh 150 pounds without gear and I am an average C class racer.  In the front end I am running 2008 CC forks with 2013 cartridges Revalved by Protune. The triple clamps are Billet Aluminum at an offset of 18mm. In the Rear I was running a 2005 sx rear shock revalved by Protune. I have the suspension valved for woods riding rocks/ enduro. The fork springs are at a rate of .42 kg/mm and the rear shock is a progressive PDS-1, 70-91 kg/mm. I am running 120mm of rider sag and still get my front end to dive on whoops at high speeds. My front end oil level is at 300cc, I dont know if this is to little or not. My bike turns quite well and rides decent in single track, in high speed stuff it gets front heavy. Does anybody know what I should be doing to help stop this diving? When I add compression dampening to the front I get harshness in the front end with little improvement of the diving. Please let me know how I can address this issue and what changes I should start making.

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1 hour ago, vic2340 said:

        I have a 2002 ktm 200 exc with modified suspension. I weigh 150 pounds without gear and I am an average C class racer.  In the front end I am running 2008 CC forks with 2013 cartridges Revalved by Protune. The triple clamps are Billet Aluminum at an offset of 18mm. In the Rear I was running a 2005 sx rear shock revalved by Protune. I have the suspension valved for woods riding rocks/ enduro. The fork springs are at a rate of .42 kg/mm and the rear shock is a progressive PDS-1, 70-91 kg/mm. I am running 120mm of rider sag and still get my front end to dive on whoops at high speeds. My front end oil level is at 300cc, I dont know if this is to little or not. My bike turns quite well and rides decent in single track, in high speed stuff it gets front heavy. Does anybody know what I should be doing to help stop this diving? When I add compression dampening to the front I get harshness in the front end with little improvement of the diving. Please let me know how I can address this issue and what changes I should start making.

Someone correct me if I'm wrong but for the 4860 mxma cc wp forks oil spec is more like 375-390 I believe, with some people running 320-350 for enduro conditions. 300 seems like it "may" be a bit low. Are you bottoming the forks and notice excessive brake dive? If so, you may want to consider adding 10-20ccs of fork oil.

You could try raising the front end a few mms as well (lower forks in the clamp). 

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I was definitely thinking of adding more oil to my forks. I just didnt know if this would really help all that much or not. I definitely bottom at times but in the woods it is nothing excessive. I didnt run a lot of oil because I heard that my fork springs are supposed to be .40 kg/mm and I have .42kg/mm springs installed. My forks are all the way low in the triple trees by the way, up to the silver cap line. I will add 20cc of oil.

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Lean back and stay on the gas lol. Add oil. May have to compromise and add some comp damping, or maybe speed up the rebound? 

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On 9/19/2017 at 11:02 PM, vic2340 said:

I was definitely thinking of adding more oil to my forks. I just didnt know if this would really help all that much or not. I definitely bottom at times but in the woods it is nothing excessive. I didnt run a lot of oil because I heard that my fork springs are supposed to be .40 kg/mm and I have .42kg/mm springs installed. My forks are all the way low in the triple trees by the way, up to the silver cap line. I will add 20cc of oil.

Curious if you added oil and/or if you liked it better? 

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Either speed up the rebound of your forks or slow down the rebound on your shock.

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On 10/20/2017 at 0:36 PM, KtmNoob69 said:

Curious if you added oil and/or if you liked it better? 

After adding the oil the front end became a lot harsher and unpredictable. It definitely was a bad move and I went to 305 cc. It is a good oil height but this bike is just not a high speed bike I suppose, I dont know what to do, it is as good as I have gotten it so far though.

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On 10/20/2017 at 0:44 PM, YHGEORGE said:

Have you discussed this with Corey?

I have but Corey is just about the busiest person I have ever met and I feel terrible calling him to ask him for advice. I called about it once but after a lot of calls to try to reach him I think I forgot what exactly I had to tell him, he was telling me I think that it may need to have the valving adjusted again.

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On 10/24/2017 at 9:56 PM, Makaio said:

Either speed up the rebound of your forks or slow down the rebound on your shock.

Thanks I do notice that my rear end likes to kick out quite often and I get bucked hard over small logs and rocks. Next I will try to slow down the rear rebound, I hope this will help with my front end staying up as well. I think if I speed up the forks anymore they will be deflecting like crazy (I believe I tried with the result being multiple crashes). They are mediocre where they are and I dont think they can get much better without some serious thought and revalving. (the clickers dont really do a damn thing, they just make the front end total crap, or where they are now which is an odd harsh/ ok feel)

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On 9/20/2017 at 2:51 AM, tom02cr250 said:

Lean back and stay on the gas lol. Add oil. May have to compromise and add some comp damping, or maybe speed up the rebound? 

That's kinda my thinking. It's not a suspension problem more so than a body position/technique problem... 

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4 minutes ago, Monk said:

That's kinda my thinking. It's not a suspension problem more so than a body position/technique problem... 

I have been keeping this in mind and really trying, but at a certain speed it has its limits and the nose dive is weird and hard to prevent, its very fatiguing pulling up super hard and gassing before each whoop while leaning back hard. I remember when I first got the forks they were straight off of a 08 505 xcf sprung for 180 pounds. They were great on whoops, the front end was so light and cushioned the hard hits well. (small hits in single track were a different story)

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I would try slowing the rear rebound

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Go faster :ride: problem solved 

The faster I go the worse the problem becomes

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Any good suspension guy will tell you that tuning your suspension for rocks, roots and single track will sacrifice the capability in whoops and high speed stuff.  These are two opposite ends of the spectrum.  My bike was done by the best guy in this area and it's pretty good in both rocks and whoops but not excellent at either.  I've got it tuned for the best possible for both, leaning a little more toward rocks.  I've had bikes that were super plush in rocks but they sucked in whoops and high speed stuff.  My CRF450R was great for high speed, whoops and MX track but sucked in rocks.  There is no perfect setup for both.  Decide which you need more and then compromise on the other.  That said, you can get close for both.  It cost me $2,400 but I have the best set up I ever have and it was worth it in hindsight.  

Clicker adjustments can help.  More compression and higher speed rebound is better for whoops.  Less compression and slower rebound is better for rocks.  Body position and speed entering whoops is important.  Crouch down and get your butt over the rear fender and keep the throttle twisted to maintain speed.

If your bike kicks you sideways over whoops, you need to speed up the rebound (go out).  If your bike kicks up or deflects up/down and clanks over whoops, you need to slow the rebound down (go in).  Then you also have the high speed rebound adjuster on the rear shock.  For rocks you probably want it 1/2 turn from all the way in.  For whoops you want it closer to the middle or closer to all the way out.  Tuning with the clickers helps for sure but your suspension should be close after it has been done if it was done by a good shop.  I've had experience with good and bad.  Currently with my $2,400 suspension work I have not moved the clickers more than 2 clicks and it is excellent.

Edited by 4Sevens
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21 minutes ago, YHGEORGE said:

That HSC  info sounds weird/backwards to me.

You could be right.  It's one of the settings where I set it and forget it.  I'll have to check tonight.

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