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I have a 07 kxf450 that I use for hairscrambles. My question is how much should the fork tube should be above the triple clamp I have right now 10mm showing I think stock they are about 7mm but I am still having some Issues withtight corners through and around the trees. I don't mind getting some head shake as It is very rare that I get into 5 gear most almost all of my riding is in 2nd and 3rd. but how high can I go before I start taking away from the bikes basic features. I am a b class rider around 200lbs I have my front compr at 2 from fully soft and 8 rebound from fully soft

thanks for any input the bike still seems to want to steer wide

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Did you try the 08 engine mount mod? More adding the spacers to the 07? I am asking because I am about the same size and speed as you and do the same riding and want to know if it helped.. Only real difference is suspension valving, but im at 10mm or so with sag @ between 100-102.

What tire sizes are you running? I went 1 size more narrow on the front and back and it helped some.. I started that quite a few years ago probably in 08.. I am now going back to the 120 width rear tire and leaving the narrower front tire gonna see what thats like.

Another thing i did was trim about .5" off of each end of the stock renthals.

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I am only like 5mm lower than the first line on the fork so I will try going down another 4mm and give that a try I like to run about 107 to 110mm of sag so this makes sence my why my bike does not feel balanced when riding what conserned my is after I set my sag and balanced the clickers evan to stock setting when I stand next to it and push down on the foot peg the bike should come down evanly but mine the rear comes down much more than the front. Which got me to thinking that I have to much rear sag. But I like how the rear feels when riding mostly when log crossings and other obsticals it feels planted and doesn't bounce to much from side to side. So I did not want to mess with that. I will try adjusting the forks more. I don't want to jump in and get a revalve right off the bat without trying to make the stock valving work It might be good enough for me. I'm running mx51's on the bike 120s I would like to try a norrower tire and more enduro oriantated tire when mine Is wore out

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I am only like 5mm lower than the first line on the fork so I will try going down another 4mm and give that a try I like to run about 107 to 110mm of sag so this makes sence my why my bike does not feel balanced when riding what conserned my is after I set my sag and balanced the clickers evan to stock setting when I stand next to it and push down on the foot peg the bike should come down evanly but mine the rear comes down much more than the front. Which got me to thinking that I have to much rear sag. But I like how the rear feels when riding mostly when log crossings and other obsticals it feels planted and doesn't bounce to much from side to side. So I did not want to mess with that. I will try adjusting the forks more. I don't want to jump in and get a revalve right off the bat without trying to make the stock valving work It might be good enough for me. I'm running mx51's on the bike 120s I would like to try a norrower tire and more enduro oriantated tire when mine Is wore out

Yeah, that's too much sag. The bike will never turn till you get to 102 or less.

If your rear is soft, then the fork angle is constantly changing as the rear suspension goes down faster than the front.

Adjust your low high speed compression setting out 1/8 turn, and regular compression in one/two clicks. Get your sag right, your rear compression right, then work on fork height. You want the fork to be as close to the first line as possible for neutral handling. You'll never feel the fork position till you get the back under control.

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I'm with Krannie. 107+ mm of sag is just wrong. Dont think of sag as a firm/soft adjustment. Firm or soft is controlled by your spring rate and damper settings. Sag is about controlling turning behavior.

To turn properly with 110mm sag, your fork caps would have to be hitting your bars.

I'm also doubtful about you having your fork comp clicker near full out. On the 06 and 07 forks, there is usually a narrow range on the comp setting which gives the most plush ride.

I wouldn't worry too much about "when I stand next to it and push down on the foot peg the bike should come down evanly". Even if you had the low stiction 09 or later forks, I still think that's an inaccurate check for anything.

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I run 100mm and it turns better than 110 thats for sure.. It was about 110-112 whenever i first bought it...

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thanks guys i'll start over with my forks near the fist line and adjust my sag to102 and go from there i'll keep you guys in the loop on how its going thanks again

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Krannie - The 102mm sag you are refering to , is that with the rear wheel off the ground that you take the first measurement , and then when sitting on the bike in full kit , tak ethe second measurement ?

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Krannie - The 102mm sag you are refering to , is that with the rear wheel off the ground that you take the first measurement , and then when sitting on the bike in full kit , tak ethe second measurement ?

How to adjust sag;

Bike on stand, rear wheel off ground:

- Measure 'un-loaded' sag distance (axle to fender for example)

Bike off stand, no one on bike:

- Measure 'static sag' (axle to fender again, less previous measurement should = 20-25mm)

Bike off stand, rider on seat, both feet on pegs, slide up to 'attack' position:

- Measure 'race sag" (axle to fender again, less first measurement should = 100mm)

Adjust spring pre-load to achieve the above numbers.

If you get a Race Sag of 100mm, but the static sag is too big (like 30mm) then your rear spring is too stiff. You need to change the spring.

If you can get a Race Sag of 100mm, but the static sag is too small (like 10mm) then your rear spring is too soft. You need to change the spring.

Note that any compression of the rear spring of over 15mm, is going to cause binding of the spring as it compresses.

Note that for every .4 kg change in the rear, you should match the front with a .025 kg change.

Go to www.racetech.com for an 'auto-calculator' of front and rear spring rates.

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