problem

[fastkatana01]

i was riding my 600 yesterday and let go of the handlebars for a sec and it started shaking is that normal or what or what can cause that i think the wheel is out of balance or something

[deanocinq]

welcome to the tank slapper!! you can get then by wheelying or by letting go of the bars, when the bar start to shake then hits the tank hence tank slap alot of bikes do this nothing wrong with bike my mate had a tl1000 and he cured it with a steering damper and stickier tyre on the front

[rexazz2]

is the wheel straight?
Is tire pressure right?
Did you happen to be in one of those slots in asphalt , they love to put them in bad spots on highway exits

[cameron]

my kat has never suffered from this i can drop the bars at 70+ and no shaking. i would check the tire, rim and then the ballance. my friends kat was doing this because of a worn front tire? but i dont think you should accept this a normal unless you were on a crappy riding surface?

[fastkatana01]

thats what i thought

it does it at low speeds and not as bad at higher speeds

[locco]

and take a look at front suspension settings.i have bought my kat about a month ago.and the front was disturbing me at the low speed mostly then i figured out that front suspension setting are different left was 3 right was 2.
i made them both 2 and it is ok now

[fastkatana01]

where is the settings at

[Kfreak]

Top of the front forks.

[The CyberPoet]

On some bikes, ones with particularly steep fork angles, this is a common problem due to the inherent design (more flickable = less stable); this is why a steering damper is a common upgrade to such bikes. The Kat is not one of those bikes, and front wheel shimmy / head shake is something that should quiet down if induced from outside (such as going over a big bump and landing the wheel pointed other than the direction of travel) by the nature of the Kat's design -- long wheelbase & relaxed fork angle.

Since yours is occurring at speed, the problem lies in the wheels or tire(s). General rules to help troubleshoot:
(A) If the oscillation occurs less than 2 to 4 times a second at cruising speed, it's called a weave, and that's typically a misaligned rear wheel, or more rarely, very badly cupped rear tire or bad rear wheel bearings.
(B) If the oscillations occur more than 4 times a second (high speed shake), that is coming off the front wheel. The usual reason is badly cupped or scalloped front wheel (Dunlop's & Michelin's are particularly susceptible to this for some reason), bad wheel bearings, or wheel simply out of balance. Very rarely is it because of a warped front rotor.

Here's some pics -

Scalloping on the Kats (both pics also show heat-rot cracking in the grooves):

Cupping on the Kats:


Generally, scalloping and cupping both typically happen because the tire pressure is too low for the actual load weight, although rubber formulation & groove size/design play a heavy factor as well.

Cheers,
=-= The CyberPoet

______________________
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[eviilil0ne]

my kats been down twice and i have 0 shake at any speed .. definately something to look into

[Zepp]

I would want to get that figured out asap. The last thing you want to do is have something cause a serious tank slapper.

[md86]

And to add , mine has been down ..... more times than I care to count . Mine don't do that when I let go of the bars . Most likely suspect is cupping . Been there , seen that (not DONE ) .

[thetable]

Cupped tires, bad wheel bearings, loose head bearings.

[loudnlow7484]

If the oscillation occurs less than 2 to 4 times a second at cruising speed, it's called a weave, and that's typically a misaligned rear wheel, or more rarely, very badly cupped rear tire or bad rear wheel bearings.


Cheers,
=-= The CyberPoet

This would have been nice to know about 8 years ago.......

My old GSXR750 would start to weave around 120 mph..... Like it was going through a slalom or something.... it was "doing the snake". By the time it got to 140 or so, it was really scary feeling..... I never did figure out why it did that. Guess it's better that way; it kept me under 120 most of the time!

[GPon2whls]

Thread revival! I've got the same problem as the op but when i let go it starts to jerk back and forth really fast and hard first time i took my hands off to adjust my sleeve on a nice road and when i was reaching back to the bars they started to go crazy but i caught it perfectly and didnt wreck or anything but it did it again on a later day the same way again i cought it before it made me wreck or loose control. My tires are 6 months old and this happened when they were new and later. Could the wheel be put on crooked or something like that? could it be the fork settings also? i can check the fork out tomorrow in the light but also wondering what other things it could be. I've got a local bike club(some work at a bike shop that i'm sure could help too) to help me out if there's other possible things i should look for (I'm not to motorcycle-mechanically savvy)