[uKER]

I have a 2013 and it has already happened to me a couple of times that while trying to perform a quick launch, if I give it too much gas when changing gears, the front end will wobble.
The wobble is not severe and I've had no problems getting it back into control, but it is kinda worrying anyway.

I'm by no means an experienced rider, as I've only had the 636 for about 6 months now, so I'm asking you guys, is this expected?

In case it's not, is there anything I should check?
Just for the record, I'm on TC1 and full power.
Due to the situation, I haven't been able to check the display, but it crossed my mind that the wobble could come from the intermittent effect of TC.

Any input is welcome.
Thanks in advance!

 

[Jperez]

Thats what is normaly reffered as a tank slapper.

Under hard acceleration, grip the tank with your legs, apply minimum but even pressure on the bars. Or get a steering damper.

 

[uKER]

If it's normal I guess I'll have to learn to avoid and/or handle it.
I was worried that there was something wrong with the bike.
Thanks for your reply, man!

 

[richyo]

On top of what Jperez already said, you might be slightly bringing up the front wheel off the ground/un-weighting it hence the wobble?

 

[40acres]

Definitely NOT normal unless you're accelerating so hard that you're lifting the front wheel off of the ground. I've seen issues like this happen with broken/cracked motor mounts and/or bad steering stem bearings. The bearings would have to be absolutely trashed for this to happen though. It might be worth checking those two items.

 

[RJ2112]

As Jperez said, the most likely reason for the wobble is due to you holding the bars too tight. It is natural to grip very hard with your hands and arms to hold your position on the bike..... but twisting the throttle means that you do this unevenly. That means the front wheel is at an angle to the direction the bike is moving as the front wheel is being lifted off the ground by the acceleration.

When you chop the throttle to shift, the front wheel comes back down and makes contact with the road..... that angular displacement means it tries to come back in line as weight is transferred back to the front wheel.

First thing(s) to check would be the condition of the front tire, the condition of the forks (-- are they leaking, or bent?), then moving into the steering bearings as 40Acres has said......

If everything at the front of the bike is as it is meant to be, that leaves your technique as the most likely culprit that remains.

If you have the front suspension set up very stiff, you are more likely to have issues with head shake. If the front wheel cannot track the ground, and bounces off of it, you will have control problems.

 

[uKER]

Decrease of weight to the front wheel is a possibility, but I thought TC1 didn't allow power wheelies to happen. Does it?

Thanks to everyone for the tips!

 

[Off Camber]

Yes, even with TC 1 and full power, you can still get wobbles. As long as the front wheel is turning at the same rate as the rear, the front end will still lighten, and if you are giving the bar inputs the front will wobble.

 

[Brevillance]

You have to remember that TC only helps prevent power wheelies, it cant beat physics. You apply power, the weight shifts back, heavy hands on a lightened front end will give wobbles. TC will prevent a 12 o clock meetings with the pavement, but it wont be able to keep the front planted. Just work on moving weight off the hands ?

 

[Petrolsexual]

If you are hard on the gas, especially if you are using the clutch and whacking the throttle open and closed, you are throwing the motorcycle's weight backwards and taking load off the front. Then the bars are going to go whatever direction you are pulling them. I'm betting you are seeing the same thing as in this video only originating from ham fisted gear changes rather than hard drive off of corners . http://youtu.be/6o5UYJttK5Y

A good example is at about 1:22 coming off the corner.

 

[insan3guy]

Lean forward and ease off the bars

 

[Raven]

Have you had your suspension adjusted? I used to get tank slippers until I adjusted my suspension. I rarely get them anymore and when I do they are small and the bike quickly sorts itself out. Suspension is a big part of the equation. If it's not set up right your rear maybe compressing to much under acceleration, which in turn will allow the front come up easier. Same goes in the other direction, too light a setting on rebound upfront can prevent the front from maintaining contact with the road.

 

[uKER]

If you are hard on the gas, especially if you are using the clutch and whacking the throttle open and closed, you are throwing the motorcycle's weight backwards and taking load off the front. Then the bars are going to go whatever direction you are pulling them. I'm betting you are seeing the same thing as in this video only originating from ham fisted gear changes rather than hard drive off of corners . http://youtu.be/6o5UYJttK5Y

A good example is at about 1:22 coming off the corner.

Yeah, that's probably it. It doesn't go into a tank slapper because the wobble isn't strong enough to wobble the whole bike.
It's more like that light, brief wobble seen in your video.
And yeah, I'm probably going too hard on the throttle.

Have you had your suspension adjusted? I used to get tank slippers until I adjusted my suspension. I rarely get them anymore and when I do they are small and the bike quickly sorts itself out. Suspension is a big part of the equation. If it's not set up right your rear maybe compressing to much under acceleration, which in turn will allow the front come up easier. Same goes in the other direction, too light a setting on rebound upfront can prevent the front from maintaining contact with the road.

No, I have not.
I would like however to check that I'm using proper settings.
Will have to look for the suspension's recommended values and see what I'm working with.

Sorry that I'm not quote-replying to everyone that has replied, but all of your input is very much appreciated.
This topic has turned out to be really enlightening.

Thanks again to everyone.

 

[MegaTechPC]

TC1 will sort out power wheelies but in my experience the front wheel will still come up before power is reduced. In higher TC modes the wheel won't come up at all (but power delivery is very choppy). Try to keep the front wheel straight when it lifts and you shouldn't get the wobble.