bike want s to go

[garysnooker]

when i switch the bike on it some times lunges forward this as happend 3 or 4 times i made sure the pedals did not move on the bike before i switch on

 

[Nealh]

Does it have a throttle fitted ?

 

[vfr400]

when i switch the bike on it some times lunges forward this as happend 3 or 4 times i made sure the pedals did not move on the bike before i switch on

it might help to say which bike!

 

[garysnooker]

Does it have a throttle fitted ?

Hi yes its a thumb throttle

 

[garysnooker]

it might help to say which bike!

it a Kudos Tornado

 

[Cancunia]

Try holding on one of the brakes when you switch on. The brake sensor should stop the surge, but if it doesn't, the brake will help.

 

[garysnooker]

i did try that but i got a error on the display

 

[vfr400]

Can you be more specific about when it happens. There's no logical way it can do it just by switching on. Do you have to touch something first or move the bike? What sets it off?

 

[sjpt]

Try holding on one of the brakes when you switch on. The brake sensor should stop the surge, but if it doesn't, the brake will help.

i did try that but i got a error on the display

On our (different, XF07) machine you get an error if you hold the brakes during switch on, but it goes away when you release the brakes. You could try that. It may well not work on yours, and if it does you may still get a surge, just delayed till you release the brakes and the electrics kicks in.

Can you be more specific about when it happens. There's no logical way it can do it just by switching on. Do you have to touch something first or move the bike? What sets it off?

I guess that could happen if the throttle is independent from the PAS and the throttle is not properly returning to the off position.

 

[snafu]

Removed

(Posted in wrong thread)...

TTFN
John.

 

[Nealh]

Disconnect the throttle and switch on, if no surge then you will have a wire fault likely on the throttle signal line. The fault is likely a broken or intermittent wire contact, wet has got into the throttle or could be bridging a pair of pins if a waterproof connector.

There are only two options for the bike to lurch and that is PAS or throttle these are the only two drive systems.

 

[vfr400]

I guess that could happen if the throttle is independent from the PAS and the throttle is not properly returning to the off position.

It can't happen. The controller won't give power after switching on until it sees a zero thottle situation. It's a safety feature to stop what OP is describing. We need more info instead of making wild and incorrect guesses.

 

[vfr400]

Try holding on one of the brakes when you switch on. The brake sensor should stop the surge, but if it doesn't, the brake will help.

The controller also checks the brke switches at startup. If a switch is on, it'll give an error code.

 

[Cancunia]

Perhaps disconnect the throttle & PAS from the controller & then see if it surges?

 

[Nealh]

Perhaps disconnect the throttle & PAS from the controller & then see if it surges?

It won't the controller needs an input signal for it to do so, so either one from PAS or throttle. The obvious and most likely one to cause an issue is the throttle.