Power Kite Forum

Squirrelly handling on ATB

InvertedForce - 11-4-2010 at 08:47 PM

So, I decided to get comfortable on my ATB before going kiting with it and totally destroying myself.

I took it down to a local bike/jog path and everything was working great on the pavement. Board rolled smooth, turning was easy and stability was excellent barring my inexperience. We made it about 1 mile in and there was some grassy hills and crushed gravel paths. Feeling the need for speed with my new-found excitement in board sports, I gave the hill a whirl. First few passes were scary, but no problems. Up until this point, I had mostly been kicking with my right foot and my left foot was always inside the binding. Because I was constantly kicking to keep my speed up, I got used to keeping my right foot out of rear binding and closer to the middle of the board.

Since I know this changes balance and control, I figured I would try putting my back foot into the binding after pushing off towards the hill. Foot went in smooth, and I started to pick up speed. Up until this point, I probably never got going any faster than 10 or 12mph. However, this run, I started to HAUL down the hill, but to my amazement, I felt comfortable with it. UNTIL... the board started shaking violently. The handling got really squirrelly and it felt like somebody COMPLETELY loosened my trucks and they were just bouncing around. The trucks are attached firmly to the board, so thats not the problem.

Its hard to describe exactly what it felt like, but perhaps somebody has had a problem similar to this? The most I can figure is the trucks are tightened differently or not oriented correctly? Would this cause tracking problems? Perhaps a slight deviation would only be noticeable at higher speeds? I've tried just rolling the board with nothing on it, and it rolls pretty straight, so I don't think thats the problem.

Any insights?

Board is GI AK103 with skate trucks. I'm 5'10, 250lbs.

Thanks fellas.

dylanj423 - 11-4-2010 at 09:30 PM

its called "speed wobble" vibrations due to movement cause it... putting pressure on one foot (i like the rear foot) helps smooth it out.... it happens at higher spededs... the pull from a kite also gives you something to lean back against, which also helps with wobble

im afraid its not avoidable completely...

just try not to panic when it comes, and remember to put weight on your rear foot

Kamikuza - 11-4-2010 at 09:48 PM

Tighten the trucks more or put in firmer springs or the elastomer sticks, if it got channel trucks but if you're going to use the board for the kite it'll then be too stiff maybe ...
Speed wobbles ... you gotta punch through that, man - go FASTER :lol:

stetson05 - 11-4-2010 at 09:58 PM

I am not a fan of speed wobbles. I actually have two boards and one can really carve but it wobbles at speed. The other is much stiffer and harder to turn but it never seems to wobble, at least at the speeds I hit.

Kamikuza - 11-4-2010 at 10:47 PM

There's your answer ;)

arkay - 12-4-2010 at 01:27 AM

Yup, stiffer trucks will get lessened the wobble, but will sacrifice turning. the first time I felt the wobble I was going down a paved street. I someone kept it oscillating and shaved speed. Freaky the first time for sure.

InvertedForce - 12-4-2010 at 05:47 AM

Yeah, I thought I was going to be tossed off the board the first time! Thanks guys for your knowledge! It certainly helps to know Im not the only one with that problem. So faster and with a kite is key? Check!

Kamikuza - 12-4-2010 at 05:53 AM

I was joking about "punching through it" ... have no idea if going faster is the key :dunno:

My Kava has two positions for the springs and polymer/elastomer inserts ... I bought it with all the things installed so didn't know any different.
My first days riding were on a beach in NZ and I went as fast as I possibly could :lol: being ignorant of well, everything ... silky smooth ride, no wobbles!
Brought the board to Japan, then Nick the kiteboard guru tried to ride it and couldn't get it to turn :lol: so I pulled the polymer things and now use just the springs. I can turn to toeside no problems and have yet to get speed wobbles - but I doubt I go that fast and anyway, the board on it own weighs 13kg :lol: it's like 13 ply or something mad ... I have no fear about standing my fat arse on the board and breaking it - unlike my Scrub that says "Max 90kg" on the bottom :shocked2:

PHREERIDER - 12-4-2010 at 07:05 AM

dude, you need a stouter board.

(not sure of your board details), but

AK 103 comes with skate truck style and not so good for big guy needs, at speed the accelerated mass will break! the pivot point style truck just aren't man enough for the job.

you need big channel style trucks, springs or cubes . if that's what you have then king pins may be broken.

more board as well you will break that 103. i have one and @200lb. i consider it quite fragile. good for a cruise, and easy riding but rough stuff NO WAY

PHREERIDER - 12-4-2010 at 07:22 AM

the "punch through" stuff works , but i'm cruising at 25mph or so ,wobble shows up and immediately add full power, powerslide through and regain, jump or transition.

now if you not use to doing those thing @ fairly hi speed then lean back heel side powerslide it out and slow to regain. wheel weight oscillation i think is a factor, but hard to say.

InvertedForce - 12-4-2010 at 10:00 AM

I was told the AK103 is a good board for a bigger guy and a beginner because of it's wider stance with the bindings. Suppose I was to start looking for a different board, what would be a good place to start without breaking the bank? The GI was priced right at just over $150 for a brandy new board. Some of these $450 boards look out of my range as a beginner.

What do you suggest, Phree?

arkay - 12-4-2010 at 10:39 AM

I have an AK103, and I can bottom it out pretty easy. I keep to crusing and simple transitions or I fear I'll crak in in half :) I had the bionic yellows, and they are too soft for 200lbs on sand. I plan to move them to the reds, which will give more stiffness.

Insect00man - 12-4-2010 at 12:05 PM

Quote:
Originally posted by dylanj423
its called "speed wobble"


It's evidently an artifact magnified as a result of neuro-muscular compensation in attempt to maintain balance. A little bit like "sewing machine legs" sometimes experienced by rock climbers.

So, riders experiencing it need a faster CPU and faster/stronger motor-neuron system :smilegrin:

Alternatively, the effect can be reduced by dampening the frequency and amplitude at which the board/suspension moves and requires the rider to rebalance...

Stiffer egg-shocks helped for me.

Also found that carving more and going straight less helps to eliminate the effect.

PHREERIDER - 12-4-2010 at 12:32 PM

for cruise and carve the 103 is fine on smooth flat surface, but add lumpy field stuff it 'll just get beat up and crack mount plate or truck pivot. its more of long board conversion. with well controlled landings it gonna work for a while, but i can tell you i drop a few flights and drop like a rock and that board want do it long for a big guy

used 106 GI

used core 16 MBS

better for your size

InvertedForce - 12-4-2010 at 03:09 PM

Thanks! I'll start checking it out. MBS would be better of the two, no?

PHREERIDER - 12-4-2010 at 05:36 PM

mbs might be hard to find can't remember the replacement model

GI 106 more likely to find around $150-200 that's a guess, not sure, newer series may be more