ive read about people bump starting there bikes when the battery dies, but ive only seen it done on little 50s. this action has always made me ask how it works and what the "proper" method is to do it. i assume its similar to push starting a manual car.

 

This is required very often at our track events, as race/track bikes sit for periods of time in trailers and batteries just don't last that great when bikes sit a lot.

If a bike is totally dead (not even dash function) you're pretty stuck. But it takes almost no amperage to simply make spark plugs fire.

Hopefully you have someone to push you as you sit on the bike, but you can still do it solo in a pinch. We put a bike in 1st gear with the clutch pulled in, key turned to "on". When you're going as fast as you can run, you pop the clutch while giving it gas. It's going to bog (almost like it's running on too few cylinders) but you give it enough gas to make it not stall (not a handful of throttle, just 2000-3000 rpm sort of). If it starts bucking, you can pull in the clutch a bit and gas it hard to get the rpm up.

Depending on the compression, a bike can be easy or horribly difficult to bump start. Two stroke 125/250 bikes with 11:1 are easy. 12:1 is so so. Any race bike with high compression pistons (13-14:1) are nearly impossible and need a starter motor.

Does that help a bit? Not a perfect technique to it, but it works if there's even a little bit of juice left, just like a manual-shift car.

 

thanks for the info. thats pretty much what i was wondering?

 

It's sometimes a bit easier to start in second gear and try to make sure to get some weight on the rear tire as you let the clutch out, otherwise the back tire will just lock and skid without firing the bike.

Good Luck

 

Get it in the highest gear you can. It will make it easier. If someone doesn't believe me I will explain it if you would like.

 

As Stonecold34gixxer mentioned getting weight on the rear tire, as I am pushed and I'm letting the clutch out I bounce down on the seat all in one action. Works most times

Big twins are a royal pain in the @$$ to bump start.

Cheers

 

I agree with transamlt1man comment, Keep in mind Your bikes chager is not intended to charge your battery from dead, its meant to keep your battery in a good charged condition. Doing this repeatly is hard on your bike and from experience it will cost you $$$ in the long run, just buy a proper charger(trickle charger) or a new Battery.

 

Yes your bike charging system is just ment to keep it at full charge and not ment to charge a battery completly. This could damage it after time. Same with cars