Freeway stability -- will fork upgrade help?

[AlanDog]

So I have a larger windshield, 15x44 gearing and it's pretty sweet on the freeway... but when I'm riding with my friend, who is on a Vstrom 650, he is way more comfortable at freeway speeds, at least from what he tells me. Going 70-80 with gusts of wind pushing me around is stressful for me, I honestly feel less stressed on a twisty road. I've been riding for about 6 months, have logged about 5k miles, but have never ridden before that and have never ridden anything except my ninja 250 (2007). I also have new tires (GT501 rear, Metzeler Lasertec rear).

So will a fork upgrade help with bike stability at freeway speed? Any experiences/opinions on this? I'm thinking of doing the ex500 spring upgrade (I weight 180).

Thanks!

-Alan

[Alex]

I don't think increasing the stiffness of the front end will have anything to do with the bike's sensitivity to wind.

[alex.s]

tuck more?

[oblivion007]

tuck more

[Kevin2109]

Tuck more
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[Snake]

Lay on the tank.

[DEXSPEED]

minimize drag............................................................................ ............tuck more?

[EsrTek]

[setasai]

Do you feel the wind on your body or on the bike or both? The bike will catch some wind and no matter what you do, you need to counter that. If your body is catching wind and you try to stabilize yourself using your arms then you'll transfering that to the steering. Either way, the fork has very little to do with sideways gusts.

[clintalmighty]

Wider rear tire

[AlanDog]

It's funny now with the large windshield when I get down my helmet is almost touching the windshield and I get no wind noise. This is what I have http://www.mikesshields.com/images/euro4.jpg. It could even be part of the problem, since I have a bigger frontal area--although the wind that gets deflected would end up hitting me (in a normal position) anyways...

Looking for a practical excuse for upgrading my forks--help me out here!
I was just thinking the tracking as you get blown around might be better. If the gusts are causing the bike to actually rise and fall... I will probably end up getting these, so we'll see.

Thanks all,

-Alan

[alex.s]

Originally Posted by AlanDog

It's funny now with the large windshield when I get down my helmet is almost touching the windshield and I get no wind noise. This is what I have http://www.mikesshields.com/images/euro4.jpg. It could even be part of the problem, since I have a bigger frontal area--although the wind that gets deflected would end up hitting me (in a normal position) anyways...

Looking for a practical excuse for upgrading my forks--help me out here!
I was just thinking the tracking as you get blown around might be better. If the gusts are causing the bike to actually rise and fall... I will probably end up getting these, so we'll see.

Thanks all,

-Alan

if you want to spend money on your forks get emulators and proper rated progressive springs. a properly tuned standard fork will out perform an improperly tuned USD fork any day. the only reason USD forks are better (i'm assuming you want to upgrade to USD forks) is because of the reduced unsuspended weight making the wheel able to respond quicker on the way back down due to the reduced mass... as we all remember, acceleration = force/mass, so less mass with the same force = more acceleration, meaning the fork responds faster. unfortunately our frame and bodywork wasn't designed for it, not to mention you'd have to respring almost any USD fork in order to get it correctly sprung

or you could simply add preload spacers and up the oil weight

[CmichRider]

Shoot dood, at least you have a windshield. when I'm on the highway it feels like the wind is going to carry me right off the bike!

[AlanDog]

Originally Posted by alex.s

if you want to spend money on your forks get emulators and proper rated progressive springs. a properly tuned standard fork will out perform an improperly tuned USD fork any day. the only reason USD forks are better (i'm assuming you want to upgrade to USD forks) is because of the reduced unsuspended weight making the wheel able to respond quicker on the way back down due to the reduced mass... as we all remember, acceleration = force/mass, so less mass with the same force = more acceleration, meaning the fork responds faster. unfortunately our frame and bodywork wasn't designed for it, not to mention you'd have to respring almost any USD fork in order to get it correctly sprung

or you could simply add preload spacers and up the oil weight

Actually, I was just going to install the EX500 springs as a starting point (http://faq.ninja250.org/wiki/EX500_springs_option)... this is my idea of "fork upgrade" on my budget!

[alex.s]

if you're on a budget you might want to try adding preload spacers and upping the oil weight first. it may get you what you want and will only cost about $10

upping the oil weight will make the fork damping "stiffer" or "slower"

adding preload spacers will increase the spring rate per mm from a resting point at the cost of potentially reduced travel. it's a very cheap modification and the combination of the two can get you where you want to be without spending an arm and a leg. there is a bit of work involved but not really any more than you would need to do to replace the springs with 500 springs. you may want to try it before spending money on new springs since it's so cheap.

[AlanDog]

So I finally got around to installing the ex500 springs. I'm sort of cross-posting here, just trying to get more input.

Alex, you were right, preload and oil *level* make a huge difference in the feel. I decided to raise the oil to 160mm (10wt) and tried to keep the amount of preload the same (I had to make the spacers longer because the ex500 fork spring was shorter). Wow, very stiff, not what I was expecting b/c the ex500 spring is supposedly 0.58 kg/mm, way under the 'recommended' value of 0.80 from sonic springs or racetech (for my weight, 180 lbs).

So I removed 35 mm of fork oil (back to 195mm, near the 'correct' OEM level) and now it feels softer, but still stiffer than the stock springs. So good, this is a major insight into the fact that the air captured at the top of the fork is essentially an air spring, and so the more oil, the less air, the stiffer the feel.

But I have realized that in keeping my preload *distance* the same, I have actually decreased my preload sag, since it is a stiffer spring. So I'm going to take about 1 cm off my spacer.

I'm already a pro at removing the handlebars and taking out the top cover from the fork tubes, it really is a 10 minute job *if* you have the jaw puller/spring compressor ($10 at amazon), so now changing the preload or fork oil seems like no big deal... I guess that's what you were telling me!

And finally understanding these fork emulators. It's just a check valve to relieve compression dampening, effectively making your fork softer without degrading the rebound dampening. It all makes sense now!