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Handling Question

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As my riding and cornering improves, I find that my bike starts handling differently, and I have to re-dial in my suspension setting.  I guess that is a good problem.  I am hitting bermed and flat corners a ton faster now, and I have noticed a handling problem.  I am not sure what to descibe it as...perhaps a type of oversteer.  Here is what happens:

  • Medium to fast bermed corner, or even flat corners
  • I enter standing, on the brakes (more rear bias...to help the bike hang out a bit), leaning the bike in, hips back and low, head over the clamp.  The classic aggressive corner entry positio
  • I transition to sitting forward, fade off the brakes, leg out and high, increase the lean, and immediately roll onto the gas.  I dont coast.  Coasting freaks me out...it is so unstable.
  • The first 10-15 feet after I sit are great...then as I roll on the gas more aggresively, the front starts to pull in.  The front comes down off the berm, the bike starts drawing an arc tighter than the berm.
  • Straighteing the bars does not really work, as the bike will just lean more, and I may lowside.
  • The solution with a properly handling bike is to just add more gas...and push back out against the berm
  • But that does not work.  If I add more gas...the front just pulls in more, the bike draws an even tighter arc, and the rear hangs out a bit more
  • Finally, it gets so bad that I have to reduce throttle and stand the bike up
  • This happens both directions, soft dirt, sand, loam, grippy clay, loose dry...even hard pack

The normal broad stroke setting changes would be to increase sag, or lower the forks in the clamps.  But those changes will also impact entry more than I want to.

 

Clicker changes for oversteer would normally be:

  • Less fork compression damping
  • More fork rebound damping
  • More Shock compression damping (I have found this to be the most effective in the past...especially in soft dirt)
  • Less Shock rebound damping

Adding shock LS compression damping is out.  The rear is already borderline harsh in chop.  Adding any compression also starts to take off my jump distance.  The rear will not load the spring as much...so I get less jump face rebound, and start coming up short.  I just can not add any more rear compression damping.

 

Also, if you increase fork rebound damping, the front tends to want to keep turning when you exit a corner.  I would think that increasing fork rebound damping might not work in my case.

 

So take more shock compression and more fork rebound off the table....

 

I am not sure what to try....Perhaps minute changes in multiple areas will be the way to go...

  • Add a tiny bit of sag (say 1mm static)
  • Lower the forks a tiny bit in the clamps (1 mm +/-)
  • Soften the forks a click
  • Reduce shock rebound damping a click

Suggestions are appreciated....

Edited by Blutarsky

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There was no need to write beyond your first paragraph. Going faster typically means you need to raise or firm up the fork, and/or lower the rear (more sag) . You end up loading the front more often needing firmer front. Then in fast corners you get on the gas earlier so the front disconnects too often, needing a lowered rear. Plus in fast rough straights you need more stability. It makes perfect sense to change your setup as you develop more riding speed.

You might have it backwards regarding adjustments for oversteer.

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There was no need to write beyond your first paragraph. Going faster typically means you need to raise or firm up the fork, and/or lower the rear (more sag) . You end up loading the front more often needing firmer front. Then in fast corners you get on the gas earlier so the front disconnects too often, needing a lowered rear. Plus in fast rough straights you need more stability. It makes perfect sense to change your setup as you develop more riding speed.

You might have it backwards regarding adjustments for oversteer.

 

Thanks.  I checked my clicker settings.  I have been playing with them, and I think I got a little lost.  The fork was indeed soft on compression and very slow on rebound.  I think the fork may have actually been packing down.  Does that make sense?

 

You description of what goes on as you start to ride faster makes complete sense.  Thank you.

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You're welcome.

Just in case I confused you, when I wrote the word raise, I meant raise the front end. So fork tubes lower. Or more spring pre-load or firmer springs.

Yes those clicker settings you used could cause the fork to pack down and bike to over steer. Nasty setup that one.

If you have reasonable feel for a race dirt bike's behaviour, you'll probably find a narrow range on the fork rebound clickers that works best for you. Worth experimenting to find it. When in doubt, go faster on fork rebound and keep the comp on the firmer side. That'll connect the front tire better. Then keep your weight more often forward, trust the bike and go faster. But, and there are many buts ... in soft sand it's better to slow down the rebound and firm up the comp, on both ends.

The challenge is that all the adjustment variables are interrelated. I mean springs, damping, and even how one end of the bike effects the other. Keeping simple records can save much time in the long run.  When you think the testing is hard work or wasting time, just remind yourself that you will save a truckload of riding energy when the bike is working properly for you.

Edited by numroe

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I had my forks and shock revalved by a multi-time state champion and past 500cc natl. number holder... told him I didn't want plush, just what works and I like to jump big stuff, LOL... first thing I noticed was that the front wouldn't dive going in like I was use to. BUT, over thelast few months of getting faster and gaining confidence the front is diving better, and seems to gain responsiveness as I push it. I don't think having suspension a step or two ahead of where your at is a bad thing as long as your progressing. deeper dive carves a tighter arc than less dive.. JMHO. oh, and my bottoming resistance is spot on. I like the mild black scuff under the front and rear fender.

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You're welcome.

Just in case I confused you, when I wrote the word raise, I meant raise the front end. So fork tubes lower. Or more spring pre-load or firmer springs.

Yes those clicker settings you used could cause the fork to pack down and bike to over steer. Nasty setup that one.

If you have reasonable feel for a race dirt bike's behaviour, you'll probably find a narrow range on the fork rebound clickers that works best for you. Worth experimenting to find it. When in doubt, go faster on fork rebound and keep the comp on the firmer side. That'll connect the front tire better. Then keep your weight more often forward, trust the bike and go faster. But, and there are many buts ... in soft sand it's better to slow down the rebound and firm up the comp, on both ends.

The challenge is that all the adjustment variables are interrelated. I mean springs, damping, and even how one end of the bike effects the other. Keeping simple records can save much time in the long run.  When you think the testing is hard work or wasting time, just remind yourself that you will save a truckload of riding energy when the bike is working properly for you.

 

I knew you meant to lower the forks in the clamps (raise the front of the bike up).  I have a large bermed figure 8  test track which I can do both flat corner, and berm corner testing on.  I do almost all my set up on this turn track.  I have found that when you really get things dialed for the turn track....the bike works fine everywhere else (jump, chop, braking bumps, etc).  When testing on a turn track...I can feel very minute changes... 

 

I think I may do the following:

1.  Add 1mm static sag.  I am now 27mm and 103mm on my YZ250F. Take it to 28 x 105.  I have done that before..and can feel it.

2.  Go back to the baseline Enzo set up (Forks 10 out 10 out, Shock, 10LS out, 1.25 HS out, Reb 7 out), and come up with a whole new set up with the new sag setting.

  • Set fork rebound 1st.  Add rebound till bike noticilby wants to keep turning when exiting corner.  Back off 2
  • Add fork comression till it starts to get harsh in chop and braking bumps.  Back off 2
  • Add shock rebound till it starts to pack down in chop and bracking bumps.  Back off 1
  • Add shock compression till it just starts to get harsh in chop and braking bumps.  Back off 2
  • Jump a single to flat to test bottoming.  Add HS till the rear is noticibly stiffer in bottoming.  Back off 1/4 turn.
  • Re set the shock LS compression after dialing the HS.

After I get this done...I have my new baseline. At this point, I make clicker changes to address specific handling issues with the new baseline.  I think that knowing how to set up a suspension is one key to going fast.  I have had cases where I was riding  sand track...and struggling...then I remembered....add a LOT of compression each end....rear especially.  I have literally done that...and knocked 5s off my laps times...going from tentative to completely confident. 

Edited by Blutarsky

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Have you tried dialing out some HSC on the rear?  If you sag and fork position are otherwise good, that maybe reduce your in-motion ride height enough to accomplish your objective.  I would try that first since it's easy. 

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From the first post that was made I'd simply try two clicks out on the front rebound , decreasing the fork rebound damping . that would definitely help the over steering problem . Body Language plays a big role as well along with throttle control . Maybe your a little too far forward ?  or it can be a poor traction problem in which case you might want to  soften up the low speed comp a couple clicks or 1/4 turn out with high speed and see if that helps the rear or increase Rebound damping  . You could increase you sag too . Just what ever works best for you through trial and error .

Edited by xxcody2gunsxx

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Made quite a few changes during a night session last night.  Dialed in a mm more static sag, and a mm less fork height.  Worked into a new baseline with quite a bit more front compression, and a little bit less from rebound.  The front pulling on on exit is better, but I now have a problem when I transition to sitting aggresively.  A few times the damned bike just went straight and the front plowed at that phase.  I was slower with the new settings....  Solved one issue...but traded it for another.  Perhaps I should just learn to live with the original issue and overcome it with technique (sliding my seated position back on the bike as I exit...) 

 

Riding a sandy track tomorrow...so all these settings are out the window.

Edited by Blutarsky

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Ignoring the sand tracks, which for sure need different setup, chances are good that if you work at it, you will find a setting that does everything pretty darn well everywhere.

 

Using written words, it's real difficult to help with this stuff.

 

To guess at what's going on, you perhaps need to fine tune your new setup, and actually learn to adapt to it. For example learn to seriously load the front tire much earlier going into turns.  Not go back and adapt to the old soft front and raised rear. Or maybe go half way in-between.

 

When you transition into sitting, just before aggressively taking a corner, the suspension usually unloads (extends) a lot or completely, on both ends. At that point you often need fast enough rebound on both ends to maintain some tire contact and control. The springs also need to be supple enough at full extension, which is why you need firm enough springs, and adding preload is not the answer. An example of why having enough static sag matters.

 

Another thought is that if you went too firm on the fork (comp damping, spring or oil volume), then when you do move your weigh forward, you wont get enough front end suspension/wheel travel, so the bike becomes unsettled and at some point it blows wide out of the corner. So generally you either have to ride faster or soften the front end, but fine tuning the suspension and it's just easier to ride at any speed.

Edited by numroe

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That's why you should only do one change at a time so you know what caused what. Maybe a couple clicks less rebound on your forks would have been enough.

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That's why you should only do one change at a time so you know what caused what. Maybe a couple clicks less rebound on your forks would have been enough.

One change at a time is good in theory, and best most of the time.

 

But sometimes, and I think surprisingly often, to save time in the long run, it's better to completely through out the old setup, in with the new and tweak it. Just got for it. Shoot from the hip with both guns blazing. ;)

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One change at a time is good in theory, and best most of the time.

 

But sometimes, and I think surprisingly often, to save time in the long run, it's better to completely through out the old setup, in with the new and tweak it. Just got for it. Shoot from the hip with both guns blazing. ;)

 

This was exactly what I did today.  I wanted to work to a whole new set up...

 

Did no go to the sand track.  Dialed all day long at my friends place on our turn track...one thing at a time.  My starting point was the new baseline I came up with Thurs eve.

 

The new baseline set up was really difficult as I started to ride hard.  Terrible washout/push with the front as I transitioned to sitting. Literally bars turned...bike goes straight...very light feeling in the bars when this happened.  SCARY.  Also no grip in the rear on high speed corners after I get the bike to take a set.  Dialed and dialed and christ...wouldn't you know it...I ended up right back where I started.  Fixed today's problems...but right back to the old problem....and the settings I came up with are very close to what I had when I started this thread.  Sheeesh.  The conclusion that I have come to is I need to learn to ride around the original problem...because I can not ride around the problems I had today...  I felt like an idiot who could not ride at all with the new baseline set up....

Edited by Blutarsky

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Personally, I don't think you have a suspension problem, I think you have a technique problem.

Are your elbows up? Are you weighting the outside peg? And is your head leaning in toward the center of the corner? Or outward? It should be outward.

Lastly, put your forks plush with the top of the clamps if you haven't already, and you didn't tell us what bike you have, if you are riding a Suzuki, well it's a bike that wants to turn. But I still think it's a technique issue, as I have experienced a similar type of issue, but I asked one of my good friends who is a former pro to watch me and he said I was doing some things wrong.. Which was what I listed up top.

Edited by Black450R

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Personally, I don't think you have a suspension problem, I think you have a technique problem.

Are your elbows up? Are you weighting the outside peg? And is your head leaning in toward the center of the corner? Or outward? It should be outward.

Lastly, put your forks plush with the top of the clamps if you haven't already, and you didn't tell us what bike you have, if you are riding a Suzuki, well it's a bike that wants to turn. But I still think it's a technique issue, as I have experienced a similar type of issue, but I asked one of my good friends who is a former pro to watch me and he said I was doing some things wrong.. Which was what I listed up top.

 

I think you are right...but the problem is not any the very basic things you have discussed.  I think have those down.  Last time I spent a day with an ex AMA pro who does insruction...he said my sitting cornering technique apex out was "textbook".  My transition to sitting was pretty weak, however. (hard time carrying the rear brake when I go to sit...that dance where you lift the foot off the peg and just have your toes on the rear brake lever as you sit is hard for me....), As such, I recently spent a lot of time working on that...but it was on a pretty hard packed (but still grippy) practice turn track.  I think I have developed an over aggressive technique and I may be initially sitting too far foward sometimes.  It really works well just as I sit and roll on...but as I accelerate more....things start to get out of balance.  I think it is as simple as learning to let my body slide back if I feel the front pulling in.  Problem is I have a grippy seat...and it is easier said than done.

 

As for bike...

2006 YZ250F (bored and stroked out to 315cc with one of RPMs Ice Cube kits.)

Enzo suspension + sub tanks for 185# rider, outdoor MX

350cc oil level

.45 Front Spring

5.4 Rear Spring

Sag - 104 mm rider.  30-31mm static (Enzo recommended)

Forks +4mm over the stock setting (pretty common to go +4-6mm for 06-08 YZ250f's)

Tires M403/404 12-13 psig

 

The recommended ENZO baseline setting is

FC 10 out

FR 10 out

SLC 10 out

SHC 1.5 out

SR 7 out

 

I keep ending back in this range with the settings

FC 11 out

FR 5-6 out

SLC 6-7 out

SHC 1.25 out

SR 8-9 out

 

Basically, the settings I gravitate towards will tend to keep the front running lower (less compression damping, more rebound damping)...and the rear higher (more compression damping, less rebound damping). Adding shock compression is always the thing that I really really like.  Going from 10 to 7...I am a different rider.  The increase in grip is crazy.  The front adjustments are a lot more subtle...but generally reducing the fork compression and adding rebound at the same time helps aleviate the push/washout which occurs right when I sit.  When I get the bike all dialed in like this with this set up...the problem becomes exit oversteer where the front pulls in, drawing a tighter line.....which is not nearly as bad and scary of a problem as having the thing go straight when I sit...

Edited by Blutarsky

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I felt like an idiot who could not ride at all with the new baseline set up....

 

Oh well. By giving it a go, I hope it was fun and/or educational.

 

If you swap bikes with friends, then you'll often learn a lot of things much faster.

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I think you are right...but the problem is not any the very basic things you have discussed. I think have those down. Last time I spent a day with an ex AMA pro who does insruction...he said my sitting cornering technique apex out was "textbook". My transition to sitting was pretty weak, however. (hard time carrying the rear brake when I go to sit...that dance where you lift the foot off the peg and just have your toes on the rear brake lever as you sit is hard for me....), As such, I recently spent a lot of time working on that...but it was on a pretty hard packed (but still grippy) practice turn track. I think I have developed an over aggressive technique and I may be initially sitting too far foward sometimes. It really works well just as I sit and roll on...but as I accelerate more....things start to get out of balance. I think it is as simple as learning to let my body slide back if I feel the front pulling in. Problem is I have a grippy seat...and it is easier said than done.

As for bike...

2006 YZ250F (bored and stroked out to 315cc with one of RPMs Ice Cube kits.)

Enzo suspension + sub tanks for 185# rider, outdoor MX

350cc oil level

.45 Front Spring

5.4 Rear Spring

Sag - 104 mm rider. 30-31mm static (Enzo recommended)

Forks +4mm over the stock setting (pretty common to go +4-6mm for 06-08 YZ250f's)

Tires M403/404 12-13 psig

The recommended ENZO baseline setting is

FC 10 out

FR 10 out

SLC 10 out

SHC 1.5 out

SR 7 out

I keep ending back in this range with the settings

FC 11 out

FR 5-6 out

SLC 6-7 out

SHC 1.25 out

SR 8-9 out

Basically, the settings I gravitate towards will tend to keep the front running lower (less compression damping, more rebound damping)...and the rear higher (more compression damping, less rebound damping). Adding shock compression is always the thing that I really really like. Going from 10 to 7...I am a different rider. The increase in grip is crazy. The front adjustments are a lot more subtle...but generally reducing the fork compression and adding rebound at the same time helps aleviate the push/washout which occurs right when I sit. When I get the bike all dialed in like this with this set up...the problem becomes exit oversteer where the front pulls in, drawing a tighter line.....which is not nearly as bad and scary of a problem as having the thing go straight when I sit...

Well sounds like you are trying to work toward a solution.. Raise the forks in the clamps and See what that does for you.. Try to make the transition from standing to sitting as smooth as possible and get on the gas sooner to take the weight off the front wheel and rear steer the bike around the apex. Those older yzfs are super stable down straights but don't like to turn. Good luck!

I just realized that you are at 104 sag and only 30-31 mm of static? I would try and get that static number in the 40mm range otherwise you need to change rear springs. Something isn't right there with that measurement and I would call Enzo to get their reasoning.

Edited by Black450R

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I had to use a offset axle to get my 06 yzf to turn well

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Well sounds like you are trying to work toward a solution.. Raise the forks in the clamps and See what that does for you.. Try to make the transition from standing to sitting as smooth as possible and get on the gas sooner to take the weight off the front wheel and rear steer the bike around the apex. Those older yzfs are super stable down straights but don't like to turn. Good luck!

I just realized that you are at 104 sag and only 30-31 mm of static? I would try and get that static number in the 40mm range otherwise you need to change rear springs. Something isn't right there with that measurement and I would call Enzo to get their reasoning.

 

Not sure where you come up with 40.  The generally accepted range is 30-40.  40mm static would be a pretty stiff spring at 104mm rider sag.  I have seen no one recommend a spring that stiff at my weight.  I have also seen guys with the 06-08 bikes run static as low as 27...  I rode on our turn track and fast figure 8 for about 4 hours today.  Worked around the original problem by putting my leg in sooner...and standing sooner.  Well standing is not quite the word.  If you watched me..you would think I was sitting...but my but was just hovering above the seat exiting the corner.  By moving fore and aft with my body exiting the corner...I can adjust.  Forward...and the bike draws a tighter arc...back...and it opens up.  Basically...use technique to get around the original problem.  Exhausting to ride this way...but it works. 

 

Spent some time riding my buddys KTM 450 that was valved by Dicks Racing for off road / hare scrambles type stuff... holy moly that thing handled...but it was like riding a down pillow.  Took it off a small jump a few times...jumping a little furthe each time.  At about 50'....I bottomed it out front and rear.  But it was sure fun on the bermed figure 8 track.  

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