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Discussion Starter #1
Guys I have a new KTM 690 SMC and even when I do hard nose wheelies I am only able to use about the first 2/3 - 3/4 of my fork suspension travel. It kind of feels like it is hitting hydraulic lock and the last 3-4" is not being utilized.

I've never set up an SM before. Should it be like every other bike I've set up and under the most extreme use it should use all of the available suspension travel? Of course this would cause considerable dive.

I've already softened the compression damping considerably but this has made no difference in the amount of total travel used only the speed at which it is all used up.

Should I just pull some oil out of the forks? How much to start with?

Thanks for your advise.
 

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if you bought it new, dont take any oil out but you could check the level just to verify it's where it should be. I'd put a zip-tie around one of your lower fork tubes and after some hard riding, check and see where the zip-tie is so you can see exactly how much travel you are using. The compression slows down the velocity; your spring rate might actually be a little high for your weight. I'm not positive on how KTM sets up their new street bikes but im sure there is probably something inside to prevent a harsh bottoming that might alarm a street rider. If the suspension feels good/working like it should I would'nt tear it apart but I would set sag and tune it from there.
 

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Discussion Starter #3
I use to spend quite a bit of time setting up roadrace suspension but it's been years so I've been down the roads before. My questions are specific to how 'Tards are set usually set up.

The bike is a brand new 2008 KTM (see my sig).

I already did the zip-tie trick, that's how I know I'm not coming close to using all of the suspension at this time.

I'm very familiar w/ compression adjusters, thanks though!

I'm definitely not hitting the bottoming cone as that if at the very bottom of the travel, not 4" higher up.

The suspension does not feel great, it feels like it is hydraulically locking (which is probably exactly what it is doing!)

My question is really just this : On a 'Tard should I be utilizing ALL of my suspension travel under hard riding conditions? If so I will remove some oil.
 

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I saw the signature and i've seen used 08's for sale. Great, since you do know what your feeling, i guess the next step would probably be to check oil level and possibly pull some fluid out and see how it feels/works.:bike: On the race bike on an all pavement track...I'd say no, you wouldn't use 100% of travel. It would be similar to a road race suspension in the sense that you dont want to bottom out to keep the tires under the bike and still transfering information to the rider. I use all of the travel on my race bike but this includes some hard/bad landings from jumps.:eek: Hope this helps?:thumbup:
 

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Street riding is not really hard riding for a motard bike no matter how fast you are riding. Streets don't have jumps for one thing. I don't use full travel even on a roadrace track. These bikes have lots of travel compared to a sport bike and if you are so plush that you are using full stroke the thing will be pitching like crazy and the resulting geometry fluctuations will make it really weird to ride during throttle transitions. Short answer No.
 

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Maru is pretty much correct. The long travel of the bikes means you will not and should not be hitting the lower 1/4 of travel unless hitting a huge hole or jump.

HOWEVER- if the feel at where it is stopping is harsh- then you have issues. First thing I would check is alignment and make sure the tubes are not binding at that point. If that does not reveal anything, I would make a trip to the dealer and see what they think.
 

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Totally agree with cstem and he brings up something i did not even consider because it is so automatic with my own stuff. These bikes have long forks and if they are not parellel and they usually are not on the ones i have checked, they need to be. Loosen the non brake side of the axel clamp, even spread it with a screwdriver if you have to and cycle it a few times through its travel with the brake andthen tighten down the clamp. Make sure the lower tripple tree clamps are not over tourqed.
 

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The amount of air space at the top of the forks affects how far the forks can compress. You can take out some oil to find out how that affects the suspension travel. I can't tell you how much oil cause I don't know how much is in there but I'd think maybe a half inch would be a good place to start.

If it doesn't work, put the oil back or take out more. It is all experimentation. Just keep in mind that taking out oil is going to increase brake dive.
 

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I would make sure the fork is not binding as mentioned. Next i would put some time on the bike because these forks do seem to loosen up some after breakin. You might try turning the compression adjusters out a bit. If that doesnt do the trick try increasing the airgap but only after some seat time and only if the fork is not binding and you find it still too stiff. The air spring provided by the air gap is very progressive. this helps with dive under intense braking. if you go to far with the air gap, you may find the bike pitching too much under braking. When these things pitch they lift the rear wheel under barking. Don't forget these bikes are Tall!
 

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I run my bike on the street some, Husky 450smr, and with my track settings, it hops and skips all over the place on bumpy New England back roads. On my bike, most of that goes away with some adjustment on the compression bleeds. As you have noted, this will not affect total travel to the degree that air gap adjustments ( oil level) but i guess what i am getting at is not to get too hung up on making use of all the aailable travel. These things are diffferent animals than a normal roadracer due to their heritage.
 

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Very good point on checking the forks for binding. I have seen this alot, from something as simple as the axle dragging slightly while pushing it through the fork lower bracket. Fork oil level is supposed to be 100mm plus or minus 20mm. If you have ever seen a fork dyno chart for air gap, bottoming resistance is pretty progressive. If your forks feel good in general just firm too early in the stroke, I wouldn't be afraid to pull 10mm oil level out and see how it feels to you, but I would definitly check for binding first. One helpfull trick is to take the amount of oil that you pull from the fork and put in a small sample bottle and mark it for level, so if you decide to put it back in, just measure that amount and add it back to the fork. That way you dont have to pull the springs out or anything, just loosen the caps, lower the front end and dump away. Not a huge thing, but it saves a little time if you are making multiple adjustments.
 

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Discussion Starter #12
Street riding is not really hard riding for a motard bike no matter how fast you are riding. Streets don't have jumps for one thing. I don't use full travel even on a roadrace track. These bikes have lots of travel compared to a sport bike and if you are so plush that you are using full stroke the thing will be pitching like crazy and the resulting geometry fluctuations will make it really weird to ride during throttle transitions. Short answer No.
Thanks guys. You guys were all really helpful. This post in particular really answered my question.

Thanks again!
 
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