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Do small fork height changes really make a difference on handling?

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Was going to throw this into suspension but since it's more about handling and this forum sees more activity I thought I'd try here. 

Mostly wondering is small, ie 5mm adjustments really make a noticeable difference in handling? When I bought my '17 kxf I raised the height to 7mm straight away before even riding. Handles fine, but I decided to try 10mm for the hell of it. I had a couple spills at the track last week that were more than likely rider error above all, but I started wondering if maybe it was just a touch too much for the kxf and would have caused some oversteer at all? 

I lowered them to 5mm to see if that makes a difference in handling. Granted I won't be riding the same track tomorrow, so obviously conditions will be different but I'm just wondering if the 5mm would even be noticeable much at all? Regardless I could try just playing around with it and see if I can find my happy spot 

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There are a few reasons to change fork height but one of the main reasons is due to the type of terrain your riding.   If I am in sand I lower the forks in the clamps and if I am in tight hard packed terrain I raise them giving me better turning ability.  Some people change them due to headshake or suspension balance.   

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I'm always changing my fork height and handlebar position.......I ride the same track but somedays I feel stiffer or looser body wise and what works for one day wont for the next.....I do it so much I got it down to a science and just eye ball the fork height and/or handlebar position while sitting on the bike to what I think will work....I'm usually right on after the adjustments......

I just recently got a set of handlebars with a straighter bend and that really made a difference.....turns are even easier than before and I thought it carved good before that.....

today I'm going out to ride and I bet it wont be what I like and ill find that sweet spot and all will be good in motoland......

good luck and have fun with it !!!!!!!!!!!

 

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I can feel a 1mm change in fork height. Of course, the difference is not night and day, but can still be felt.

I agree on having to check sag when changing fork height.

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The only thing I hadn't checked after changing the tube height was sag, but otherwise I think I definitely noticed a difference at the track I was at today. I generally like 108-110mm of sag personally, and since my sag was last set at 104 I figured I had to of been somewhat in that ballpark after lowering the tubes. Wet, sloppy, rutted out corners and it felt pretty good all day. I think if I had left them at the height they were at I would have been loose as hell in turns today.  I changed bar position as well, next step will be trying a different handlebar bend. Although I've never had an issue with head shake on either kxf I've had, I did notice a difference in straight line stability as well and the way it tracked through the loose stuff. 

Was tempted to go even a couple mm lower, but there's always next week. 

Edited by Dolamite

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here's one to ponder: does raising or lowering fork in clamps put more or less weight on the front end ? while accelerating or braking?

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3 minutes ago, highmarker said:

here's one to ponder: does raising or lowering fork in clamps put more or less weight on the front end ? while accelerating or braking?

More when your forks are lowered, and yes for both... 

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fork height.JPG

 

 

No doubt raising or lowering the rear end (sag) also changes the same parameters.

Edited by mlatour
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Just now, mlatour said:

No doubt raising or lowering the rear end (sag) also changes the same parameters.

Well, yes and no, it is different, as you are steepening the swingarm angle more than the change in angle of the bike from raising the rear. Raising/dropping the front, and raising/dropping the rear have very different effects. Not just swingarm angle, but you are of course moving the cog the other way too.

Edit; You also alter where the linkage sits in its progression curve when you mess with the rear. Lowering the front will stiffen it (less leverage to flex the forks). Both lowering the front and raising the rear also effect the dive/weight transfer under brakes, the steeper the front is, the less it dives. The steeper the rear, the more it squats under brakes, and stands up under power (this is where the traction, or lack of comes from).

This is all stuff learnt from asphalt track bikes, but It will all still apply to dirt bikes too.

Edited by DEATH_INC.
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