Jump-starting bikes?

[Mikkel]

As I left my office at uni today and got out onto the parking lot I saw this fella dragging his bike and of course asked him what was up.

He had a flat battery and we did what we could to jump start it - but to no avail. Unfortunately I didn't have any jump leads in my car or I would have given that a go.

So, I was wondering what is the best way to jump start a bike?
What gear? (Seemed that the wheel would just skid if we used 1st unless he was sitting on the bike and I pushed while run behind him - it was raining though!)
They do run on 12 volt I assume so using jumper cables with a car would be ok right?

[The Pastor]

I use 2nd or 3rd to push start bikes.

If you use first you kinda have to jump on it when you dump the clutch.

[kave]

I always jump start in 2nd, and I have had to do it a lot. You dont need a huge amount of speed to jumpstart either, normally I find that the equivalent of a slow jog is more than sufficient, it pays to get as much weight over your back wheel as you can to help traction.

[nodrog:Me]

As I left my office at uni today and got out onto the parking lot I saw this fella dragging his bike and of course asked him what was up.

He had a flat battery and we did what we could to jump start it - but to no avail. Unfortunately I didn't have any jump leads in my car or I would have given that a go.

So, I was wondering what is the best way to jump start a bike?
What gear? (Seemed that the wheel would just skid if we used 1st unless he was sitting on the bike and I pushed while run behind him - it was raining though!)
They do run on 12 volt I assume so using jumper cables with a car would be ok right?

2nd gear is a better option for push starting. and if jump starting a bike with a car i always use computer proof leads and never have the car running, just to avoid any damage due to voltage spikes.

[Swoop]

Pretty easy.

A nice downhill incline is best... pushing it to the top of the incline is not fun.
Check fuel is on.
Check kill switch!
Ignition on.
1st gear selected with clutch held in,

When heading down the hill, release clutch and hey-presto!

[Mikkel]

Thanks a bunch fellas!

[paturoa]

Second gear, clutch in (or neutral) until up to a good speed, the dump the clutch at the same time as jumping onto the seat to increase traction.

If it is an injected bike, with an electrical fuel pump (ie all of them) and a really flat battery, don't bother.

[The Stranger:Me]

2nd gear is a better option for push starting. and if jump starting a bike with a car i always use computer proof leads and never have the car running, just to avoid any damage due to voltage spikes.

Who's this using Gordies account?
A serious reply, no sarcasm, no inuendo or smut - WTF.

[Tank]

As I left my office at uni today and got out onto the parking lot I saw this fella dragging his bike and of course asked him what was up.

You know that he was probably stealing it right?

[xwhatsit]

As I left my office at uni today and got out onto the parking lot I saw this fella dragging his bike and of course asked him what was up.

He had a flat battery and we did what we could to jump start it - but to no avail. Unfortunately I didn't have any jump leads in my car or I would have given that a go.

So, I was wondering what is the best way to jump start a bike?
What gear? (Seemed that the wheel would just skid if we used 1st unless he was sitting on the bike and I pushed while run behind him - it was raining though!)
They do run on 12 volt I assume so using jumper cables with a car would be ok right?

No need for jumper cables, that's a pain in the arse. Got to find somebody else, a set of jumper leads, try not to fry your bike (bike reg/recs and CDIs seem to be pretty delicate, I've heard of these failing supposedly due to jump starting, YMMV).

I bump start my bike probably every 3 days or so, and certainly on every long ride. Once it's hot, there's no way you can start it off the kick until it's cooled somewhat.

Add to that it's a reasonably decent compression single (well, compared to ancient BSAs and GN250s), you've got to learn how to bump start properly.

I use 1st gear -- you may need it for the higher RPM it offers over 2nd gear if the bike is particularly stubborn. The issue with this is that especially with thumpers you will lock the rear wheel (as you found out). To avoid this, put the bike in gear and roll it back against compression until you can't go back any further. This means the piston is just after TDC; this way you'll get a full cycle and hopefully a spark before it hits compression again and the wheel locks.

In addition, if your bike is arse-light and a thumper like mine, the wheel will still lock (even in 2nd gear). So what I do is time the releasing of the clutch to when my arse crashes down on the seat side-saddle. Then carefully grab a bit of throttle after it cracks into life and swing your leg over the seat.

Way cooler than that electric-starter horseshit. Only girls and pansy-boys use them.

[skelstar]

Made some leads that are wired permanently to my batt and go up into the tail-section and end in two bullet style female connectors. They won't short. Made another couple of leads with male bullet connectors on one end, and a battery clip on the other - it sits in the tool compartment. Used them in anger today and it was FRIGGIN easy.

Love Italian V-twins.

[mdooher]

My ST2 (No kick and electronic ignition) has one of those cigarette type connectors. I normally connect my trickle charger to this. I have made up a lead that goes into this thing and has battery clips on the other.

I have also made up a similar connection for the wife’s GSX250 and since we normally ride together we can just mate the two bikes if one is in need of a pick up.

If you are going to use the cigarette lighter power connector for jump starting you need to upgrade the fuse. The wires do get slightly warm during the jump but that’s all

[NighthawkNZ:Me]

If its electronic ignition you need to have at least enough power to bring up the lights on the dash before you can jump start it... Else you will need to jumper leads.

I use 3rd or 4th to crash start, clutch in, push to speed, puff and pant... drop clutch while jumping on to give traction, give blurp on throttle... swear and curse... try again

[Mikkel]

You know that he was probably stealing it right?

Hehe, well he did have the keys... (not that keys can't be stolen)

One thing about this bike was that it was impossible to turn the headlight off (it was dim, but still on) when the keys where in the ignition.

Of course something else could be wrong besides a flat battery. We couldn't get it going that's for sure.

[pritch]

The ease with which a jump start can be done depends on the bike.

Little two strokes, you can do it seated with a sort of duck paddle. With big thumpers your arse needs to hit the seat from a great height just as the clutch drops.

(There speaks the sad voice of Brit bike experience :-)