RooiPhilip
Race Dog
Right. Let's get to the point.
I am very happy with my KTM. The suspension on that thing is out of this world, but for two specific instances.
Loaded up with two 45L panniers (Camping gear, food and brandy) at the back, and 6L fuel. Nothing major with regard to weight, no pillion.
Suspension setup: Set to Sport setting, with increased rear spring preload (set to fully loaded setting)
Then for some reason, I experience a weave at speed 130-140+ kph. Bike tracks straight, no problems. Then you get a bump, or uneven tar, and it goes into a headshake/weave of unprecedented magnitude. It is like experiencing a tankslapper on dirt. Just more scary at 150 kph on Tar. Fucking ENOUGH. It's gonna be sorted now!
So I took my front preload down a turn, to be spot on for fully loaded setting as per the KTM manual.
Shakes are better right. The frequency of the shake is decreased. Therefore it is less sensitive when going into this shake/weave, but when it does, the amplitude is a bit higher(read more violent).
So I increase rebound damping on the front by 3 clicks. Now the forks are more plush, as is expected, steering feels more numb, which initially is good, because it takes even more to get it into that tankslapper feeling. But then, when it does, you fucking shit yourself proper!
Then I decrease the rebound damping to sport, and take it two clicks lower, as to harden the front up. Now the suspension is harder, but it goes into the weave easier, much easier, but somehow it feels less threatening.
Now my question becomes. How in the fuck do I get this thing stable on tar, with panniers, at 150 kph + ??? ?
I have no problems on dirt, since you rarely exceed 120/130 kph. But when you do, and the dirt is compact, I get the same sensation. It is completely fucked. I don't enjoy this anymore. :dousing:
I don't want to fit a steering damper. You may want to ask why? The thing is, on gravel/sand/sand highway, even loaded up, I like how the steering behaves when the terrain becomes unruly. How the front drifts when crossing the middleman in a dust highway, and how it misbehaves in the sand. The response from the terrain is incredible and very manageable and continually predictive. That is why I ride. Controlling those situations are brilliant! I don't want to go numbing those responses up by fitting a steering damper. Nor do I want the option.
What I want, is a suspension setup solution to cure this problem of mine, and to understand why it happens, so if next time when I am loaded even heavier, I can adjust it myself until it is perfect, which as of now, I am unable to do.
Failing that, go for a suspension upgrade. I have been reading the threads dedicated to upgrades, and if I don't find my solution in the suspension setup, I shall go that route. But let's try the cheaper option first.
Just some technical aspects before you ask.
It's not the knobblies. I have fitted two different pairs on knobblies, and one set of street tyres, and it happens similarly.
It does not occur when the panniers are not fitted, even when riding pillion it seems not too bad. When it is only me on the bike, there is no problem whatsoever.
I weigh as of this morning 109 kg.
Can any of you wise dogs shed some light? Or failing that, just propose some theoretical solution that I can try?eepwall:
I am very happy with my KTM. The suspension on that thing is out of this world, but for two specific instances.
Loaded up with two 45L panniers (Camping gear, food and brandy) at the back, and 6L fuel. Nothing major with regard to weight, no pillion.
Suspension setup: Set to Sport setting, with increased rear spring preload (set to fully loaded setting)
Then for some reason, I experience a weave at speed 130-140+ kph. Bike tracks straight, no problems. Then you get a bump, or uneven tar, and it goes into a headshake/weave of unprecedented magnitude. It is like experiencing a tankslapper on dirt. Just more scary at 150 kph on Tar. Fucking ENOUGH. It's gonna be sorted now!
So I took my front preload down a turn, to be spot on for fully loaded setting as per the KTM manual.
Shakes are better right. The frequency of the shake is decreased. Therefore it is less sensitive when going into this shake/weave, but when it does, the amplitude is a bit higher(read more violent).
So I increase rebound damping on the front by 3 clicks. Now the forks are more plush, as is expected, steering feels more numb, which initially is good, because it takes even more to get it into that tankslapper feeling. But then, when it does, you fucking shit yourself proper!
Then I decrease the rebound damping to sport, and take it two clicks lower, as to harden the front up. Now the suspension is harder, but it goes into the weave easier, much easier, but somehow it feels less threatening.
Now my question becomes. How in the fuck do I get this thing stable on tar, with panniers, at 150 kph + ??? ?
I have no problems on dirt, since you rarely exceed 120/130 kph. But when you do, and the dirt is compact, I get the same sensation. It is completely fucked. I don't enjoy this anymore. :dousing:
I don't want to fit a steering damper. You may want to ask why? The thing is, on gravel/sand/sand highway, even loaded up, I like how the steering behaves when the terrain becomes unruly. How the front drifts when crossing the middleman in a dust highway, and how it misbehaves in the sand. The response from the terrain is incredible and very manageable and continually predictive. That is why I ride. Controlling those situations are brilliant! I don't want to go numbing those responses up by fitting a steering damper. Nor do I want the option.
What I want, is a suspension setup solution to cure this problem of mine, and to understand why it happens, so if next time when I am loaded even heavier, I can adjust it myself until it is perfect, which as of now, I am unable to do.
Failing that, go for a suspension upgrade. I have been reading the threads dedicated to upgrades, and if I don't find my solution in the suspension setup, I shall go that route. But let's try the cheaper option first.
Just some technical aspects before you ask.
It's not the knobblies. I have fitted two different pairs on knobblies, and one set of street tyres, and it happens similarly.
It does not occur when the panniers are not fitted, even when riding pillion it seems not too bad. When it is only me on the bike, there is no problem whatsoever.
I weigh as of this morning 109 kg.
Can any of you wise dogs shed some light? Or failing that, just propose some theoretical solution that I can try?
eepwall:
