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Fork height question..


mak595

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OK, so my ktech 0.9 springs have arrived with my oil so after the weekend, i'll crack on and get them fitted, im also installing a 07 ZX6r rear shock.
 
With the ZX shock being 10mm longer than the stock shock and the stiffer fork springs, whats the general consensus regarding fork height, flush with the yokes or 5mm (or more) protruding ?? 
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I just got my upgraded fork cartridges installed and professionally setup yesterday by Barry at KFG Motorsports/GP Suspension in Auburn. Keep in mind I also have a Penske rear shock with ride height adjustment.
After adjusting the spring preload to set proper sag, he increased the ride height on the shock about 5mm, he said it was for 2 reasons, first to lessen acceleration squat and second to increase a forward weight bias for more sporty cornering (which I like).
If you dont have a ride height adjustable shock you can tackle the other end and raise or lower the forks in the clamps a few mm at a time. I would definitely ride it flush first under varying speeds and conditions to see how you like it (you are changing alot at one time). When I first got my bike I didn't like the flighty feel of the front end at speed or under acceleration. (a lot of that I blame on the stock suspension) so I raised the forks 10mm in the clamps and the handling improved immensely, for me.
If you are getting stiffer springs, your front end may already feel a little taller (mine did) since the bike isn't settling as much in the stroke with the weight of bike and rider, so you may be just fine leaving them flush. But dont be afraid to experiment a few mm at a time, you cant hurt anything.

***2015 Candy Red FJ-09***

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First, set fork and shock rider sag from 1/3 to 1/4 total travel. Might as well start with fork height close to middle. Test ride, careful to check to make sure you do not get into a wobble situation. Front end too high, or two low at the extremes can cause wobbles. Once you get close, ride around an average corner at average speed. If the bike tends to turn sharper, and you have to keep correcting the bike outwards to compensate, lower the forks / raise the front end. If the bike does not turn sharp enough around the corner and you tend to keep correcting the bike inwards, raise the forks / lower the front end.
 
 
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I just got my upgraded fork cartridges installed and professionally setup yesterday by Barry at KFG Motorsports/GP Suspension in Auburn. Keep in mind I also have a Penske rear shock with ride height adjustment. After adjusting the spring preload to set proper sag, he increased the ride height on the shock about 5mm, he said it was for 2 reasons, first to lessen acceleration squat and second to increase a forward weight bias for more sporty cornering (which I like).
If you dont have a ride height adjustable shock you can tackle the other end and raise or lower the forks in the clamps a few mm at a time. I would definitely ride it flush first under varying speeds and conditions to see how you like it (you are changing alot at one time). When I first got my bike I didn't like the flighty feel of the front end at speed or under acceleration. (a lot of that I blame on the stock suspension) so I raised the forks 10mm in the clamps and the handling improved immensely, for me.
If you are getting stiffer springs, your front end may already feel a little taller (mine did) since the bike isn't settling as much in the stroke with the weight of bike and rider, so you may be just fine leaving them flush. But dont be afraid to experiment a few mm at a time, you cant hurt anything.
Auburn... CA?

'15 FJ09

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K-techs are labeled in N/mm last I remember. So it's 9.0N/mm (or it says 8.8 on the side which is equal to 0.9kg/mm). with you on the bike, you have 30mm shorter than max? And you've got the preload turned all the way in (clock-wise?) Turn that preload out (ccw) till you get a whole lot closer to 40mm.
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K-techs are labeled in N/mm last I remember. So it's 9.0N/mm (or it says 8.8 on the side which is equal to 0.9kg/mm). with you on the bike, you have 30mm shorter than max? And you've got the preload turned all the way in (clock-wise?) Turn that preload out (ccw) till you get a whole lot closer to 40mm.
Ok, measured the fork with front wheel off ground, chrome fork measurement is 150mm, to get to 120mm (30mm rider sag) the preload is fully wound down, (no lines showing) with me sat on the bike, does that make sense? 
 
 
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> does that make sense?
yes, but no. why would you turn the preload to max? unwind the preload the whole way and remeasure sag, and pay mind to stiction. You want to get down to 115-105 with teh ideal target right around 110.
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stiction is a function of component alignment (triples, fork tube, axle) and seals. Greased seals will have less. SKF's should have a lot less. "dry" OE seals probably stick more than you'd like. If the numbers look high, I recommend loosening the axle pinch completely, and the upper triple and 'ramming' the bike into a curb or vertical wall straight on - or otherwise compressing the front without using the brakes. If that sounds a bit naff, (i'll give you that) then "just" snug the top triple pinch bolts (leave the axle pinch loose) and go for a short ride where you have the opportunity to 'hit' a few decent pot holes (eg. 1" deep).
 
Then dismount carefully (try not to put bike too far off vertical), put it on centerstand and then torque the top triple and axle pinch. See if things improve.
 
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