Questions for you landboarders out there. I need to eliminate speedwobble at "high" speeds. Nothing extreme, but think like 25 mph and more. I have a trampa with Scrub Channel trucks (it's in my avatar). The springs/dampers are set on the middle of the three holes. Inside the springs are green (medium) Trampa Dampa's.

I want to adjust the stiffness of the truck to further minimise speedwobble. It's already a hundred times better then my skate trucks used to be, but i can always use less wobble. I can do two things:

- Put the springs/dampers on the outside of the three holes. Since they're further away from the center line of the truck, there will be more resistance, meaning i'd have to push harder on the heel- or toeside to steer the board.

- Replace the green Trampa Dampa's by red ones (Stiff), keeping the springs/dampers on the same middle setting. The added stiffness should increase resistance, once again making me need to push harder to (accidentally) steer the board and make it wobble.

What i want to know is: what's the difference between the two options? I can't imagine they have the exact same effect and feel to the board, there has to be some difference. I just can't figure out what it is without actually ordering a set of Dampa's, borrowing a bench vice to open my trucks up, and trying it all out. So i'm doing the next best thing: asking you guys. Which option would be best for eliminating speedwobble?

By the way: i know people are going to tell me to "just lean back into the kite more", and that's fine when riding 90 degrees against the wind direction using a depower kite. It's not an option however, when riding straight downwind ("chasing" the wind) in 45 knot winds using a custom 1.4 square meter two liner kite that can do 4 loops through the powerzone each second.

Noone seems to know? :puzzled:

gear adjustment won't really help the problem.

while riding at higher speeds , move forward with your weight shift to your froward foot. this is an ON TOP relaxed stance (hips forward as well). very much an up right position, kite tension is present and should have room to add speed with VERY little power. to check things, head /body should be almost over front trucks.

weighting the FRONT TRUCKS can increase the stability and reduce chance of wobble.

oh! be ready to lay(fall) back and power through wobble should it arrive. speed kills!

there you go .

I am not really a truck specialist but you could consider de-wedging your trucks (reducing truck pivot angle)...board will be less maneuverable but also less wobble prone...

Quote:

Originally posted by Pulsar What i want to know is: what's the difference between the two options? I can't imagine they have the exact same effect and feel to the board, there has to be some difference. I just can't figure out what it is without actually ordering a set of Dampa's, borrowing a bench vice to open my trucks up, and trying it all out.

It's not a matter of difference, it's a matter of degrees.

On a channel truck you have 3 adjustments.


1. You can swap out the elastomers (eggs on MBS, polyurethane shocks on GI, and Dampas on Scrub/Trampa).
   
2. Vary which hole you mount the spring/elastomer assembly in.
   
3. Tension or detension the compression on the spring by adjusting the hex bolt.
   

They all do the same thing... adjust turning resistance. The difference is that 1 is a coarse adjustment, 2 is a medium adjustment, and 3 is a fine adjustment.

There are great number of thread on SurfingDirt about reducing wobbles by taking the spring out entirely and going with one of the higher durometer (harder) Dampas/eggs. Depending on the truck, tophat, and elastomer. some folks have been very pleased with the setup.

All that being said, go back to the scenario you described:

Quote:

Originally posted by Pulsar It's not an option however, when riding straight downwind ("chasing" the wind) in 45 knot winds using a custom 1.4 square meter two liner kite that can do 4 loops through the powerzone each second.

45 knot = 51.7850752 mph.... in pretty ballistic winds a 1.4m two line kite is hauling you downwind. As it sweeps through various parts of the wind window it is going to be exerting pull on you at different angles. Sometimes the pull is going to behind the board and sometimes is it going to be in front of the board. Depending on the kite's actually position in the wind window the amount of pull is going to be slightly different even if the wind is fairly constant. Wobble is pretty much the only end result you could get.

This is above and beyond whatever surface irregularities you are riding on are adding to the mix.

ATB,
Sam

it's not the trucks dude,it's you. I agree somewhat with Phree, but I put my weight on the rear truck.I get the best result by tightening the muscles in my leading ankle. I have a Scrub Quasar w/ channel trucks and it gets speed wobble like mad.I now also have a Trampa w/ VerTiGo trucks and green dampas and I have yet to get speed wobbles on it. Spring stiffness may be the real culprit here.

my channel trucks are totally loose with a bunch of slop. i can easily at 30 mph no trouble at all in a relaxed forward stance. kinda like "hang ten" on a long surf board but with side canter.

a friend who has decent atb skills and pro level kitesurf skills can ride my board but gets wobble at about 10mph and truly unable to ride it at speed because of the super loose trucks and lack of controlled balance stance. watch some long board downhill skate board guys , dead straight runs they standing on the front trucks .

WG - your right, either one LOADED dominates the truck and forces a true track , front or rear works but one has to be loaded, if you are centered they will try to collide!

Some pretty diverse advices inhere. Thanks for the input, i'll be trying a few things!

I can find eggs and the matrix pro bushings, but the adjuster screws aren't listed anywhere. My trucks blew up and I couldn't recover all the pieces. BTW I have the standard non alu matrix so I'm not sure if the pro bushings will fit. The mbs spare parts kit was the only source I saw with 1 adjuster screw and I need two. Damnit. Spare parts or a new set of trucks for a next shock wave ?

It could just be a part that MBS hasn't assigned a SKU # to. Best bet is to contact an MBS dealer directly and they should still be able to get you a price quote for it.

German MBS dealers can be found half way down this page:
http://www.mbseurope.com/stockists/

ATB,
Sam