[Ohiorider]

420 Rancher surges on takeoff. However, if you shift to neutral and back to first, it runs perfectly. Happens, and fixes the problem 100 % without fail. That would seem to be something electronic getting reset. Was surprised to not see this in any of the "surging" threads i read.
Anyone know what causes this. Thanks.

 

[retro]

Year and model please? If you have an EFI motor its possible that you have a sensor issue. Likely a dirty/wet plug... you might find a copy of the service manual HERE.

Welcome to the forums!

 

[Summers]

Did you ever figured out what the cause of this issue was? My 2010 420 Rancher ES is doing the same thing, and I can shift to neutral and back and all is good.

 

[Mechanicmatt]

Did you ever figured out what the cause of this issue was? My 2010 420 Rancher ES is doing the same thing, and I can shift to neutral and back and all is good.

Does this only happen when you start in gear?

 

[Summers]

I checked and yes it only does it if I start it in gear.

 

[Mechanicmatt]

OK. It'll be the brake lever not sitting back onto the brake light switch. It could be the pivot bolt sticking. Try pushing the brake lever forwards when you start it to see if that's the cause.

 

[Summers]

Ok I’ll try that and let you know if that works. Thanks

 

[Summers]

That was it. Can you explain to me how that switch causes the surging? Because I never would have thought of that being the issue. Thank you for your help, I appreciate it.

 

[BHM]

OK. It'll be the brake lever not sitting back onto the brake light switch. It could be the pivot bolt sticking. Try pushing the brake lever forwards when you start it to see if that's the cause.

Have not tried this yet but certainly sounds like it could be the issue. My bike has been doing it for a while and now that I think about it, I have trouble with the brake lever getting stuck. Thanks for the suggestion!

 

[Mechanicmatt]

That was it. Can you explain to me how that switch causes the surging? Because I never would have thought of that being the issue. Thank you for your help, I appreciate it.

When starting in gear the engine won't rev up for safety so if you start it with full throttle it doesn't just take off on you. When the brake is released it signals the ecu to say you are setting off, meaning you're in control. Naturally you wouldn't let go of the brake if you were panicking.