Cold stumble

[DarkKnt]

Most of us are familiar with it; drive off before the bike is fully up to temperature and it will stumble slightly when brought off idle. My bike has pretty much always done this, and I will usually let the bike warm prior to pulling away. I've noticed lately that it is much more pronounced than it used to be. It runs flawlessly when fully up to temp, but will actually require feathering the clutch sometimes to prevent a big "lurch" if I am in a hurry and don't let it warm up. All regular service (plugs/oil/filters) is up to date and everything is stock. 85K km's. I think I'll run some fuel system cleaner through it and see if that does anything, as I have never done that to this point. I usually use Chevron fuel, which is reputed (falsely?) to contain excellent detergents, so thought that injector additives weren't necessary. The fuel system is the only thing I can think of that would change over time. I got over 60K km's out of the original plugs and only changed them out of boredom. These ones have less than 25K so don't think they are the issue.
Anybody have any wisdom on this?

In the meantime, I guess I'll just let it warm up!

[Sorcerer]

Have you done the ECM reset?

[DaWadd]

Myself, the ECM reset cured it for a very brief time(days) but always came back. I know when its going to happen so I just roll on the throttle a bit harder. Only real solution is let it warm up. Guhl reflash supposed to work but they won't do it anymore.

[DarkKnt]

Have you done the ECM reset?

Haven't recently, no. I'll try that again.

[DarkKnt]

Myself, the ECM reset cured it for a very brief time(days) but always came back. I know when its going to happen so I just roll on the throttle a bit harder. Only real solution is let it warm up. Guhl reflash supposed to work but they won't do it anymore.

Has Guhl stopped doing the ECM altogether?

[DaWadd]

Yes. No more reflashes on ecm’s with a vin I hear. It’s on their website.

[willtill]

Interesting. Wonder why?

ECU FLASHING
ECU modifications for any vehicle with a VIN number or registration are not supported. Please do not send any ECUs from any vehicles that have a VIN number, have had a VIN number or any vehicle that is or can be street driven. This includes ALL motorcycles. Any motorcycle ECU sent to us will not be modified and will only be returned at the owner’s expense.

Disclaimer- All Guhl motors products are for closed course racing use only and are not legal on public roads.

[F6Dave]

Interesting. Wonder why?

ECU FLASHING
ECU modifications for any vehicle with a VIN number or registration are not supported. Please do not send any ECUs from any vehicles that have a VIN number, have had a VIN number or any vehicle that is or can be street driven. This includes ALL motorcycles. Any motorcycle ECU sent to us will not be modified and will only be returned at the owner’s expense.

Disclaimer- All Guhl motors products are for closed course racing use only and are not legal on public roads.

The EPA knows what's best for us.