Starter amps

[ST98]

Does anyone know how many amps the apex starter uses?

 

[Tork]

Well a battery like the Yuasa 14 series can deliver over 100 CCA (cold cranking amps) Nothing in the system can resist that down with the thick cables and all. Yuasa does not give cca but other manufacturers so, so my most accurate guess is 160 amps. The starter motor has to be able to handle all the juice the battery can throw at it.

 

[LazyBastard]

Actually Tork, its the other way around. The battery has to give the starter all that it wants.

 

[Tork]

Actually Tork, its the other way around. The battery has to give the starter all that it wants.

Trouble is it is hard to answer ST 98's question.

This info is for a 3 liter motor

If you've gone through all the items above and the starter is still acting up, its time for a little bit of re-design. From the factory on certain years, the starter solenoid is operated directly off the ignition switch. Over time the switch contacts can wear, the wiring and connectors can age and increase in resistance, etc. A solution is to use a relay to power the solenoid. Use a standard 30A headlight relay, wire the relay coil to the ignition switch and then use the relay contact to power the solenoid. So now the ignition switch only had to supply a milli-amp current to operate the relay and the relay supplies the higher current required by the solenoid (which in turn supplies the 100s of amps needed by the starter motor itself).

In a perfect world yes the starter motor draws what it wants. But on a cold day when the system is taxed the most and highest amp draws are needed, it sure seems to me that the battery is the limiting factor. So by the different speeds the motor will turn, depending on the charged state of the battery, I still say that the starter motor can handle everything that the battery can throw at it.

[/quote]

 

[ST98]

Amps

The cable that goes from the battery to the starter should be the limiting factor shouldn't it. Meaning a prolonged turn would melt the sheath off to small a wire thus part of the 30 seconds. Maybe I didn't ask the right question. What is the size of the wire that goes to the starter from the battery?

 

[Tork]

Re: Amps

The cable that goes from the battery to the starter should be the limiting factor shouldn't it. Meaning a prolonged turn would melt the sheath off to small a wire thus part of the 30 seconds. Maybe I didn't ask the right question. What is the size of the wire that goes to the starter from the battery?

That is what a 1/4 inch or more of stranded copper. It is bigger than wire I work with that takes 400 Amp 460 AC volts. I really think the limiting factor is the solenoid but more how long the motor can take it.. But this is not generated current, it is lead acid battery wich can only give you so much for so long anyway.

Why are you asking? Project planned? Sometime that will help you get the info you need

Ok figured it out maybe. Jumper cables?

 

[LazyBastard]

You have to also consider the fact that if it is very cold out, the battery will NOT be as strong. In a battery you have a chemical reaction, which is very strongly dependent on the temperature. For every 10 deg C increase in temperature, the reaction rate DOUBLES.

 

[fxr]

amps

hey tork i,m staying out of this. i,m just saying thanks for the heads up on the booster cables. i ordered a set the other day. now that we have all this storage on the new apex i need stuff for the front storage bag

 

[ST98]

My apologies

My apologies for not posting why I wanted the information. I was looking for the smallest wire I could use for jumper cables. If I used the amount of amperage and then used the appropriate sized wire for 30 seconds without melting the sheath I figured I could make a small set of jumpers. I was going to do a little math and all I needed was the draw amps. I certainly didn't mean to cause any problems. Thanks for the info.

 

[Tork]

Re: My apologies

My apologies for not posting why I wanted the information. I was looking for the smallest wire I could use for jumper cables. If I used the amount of amperage and then used the appropriate sized wire for 30 seconds without melting the sheath I figured I could make a small set of jumpers. I was going to do a little math and all I needed was the draw amps. I certainly didn't mean to cause any problems. Thanks for the info.

Oh heck no problem all you did was nicely ask a question. I was trying to stay focused on the info you wanted which makes sense because it is your thread . I finally suspected jumper cables, let me post a link for you then I will explain why.

[edit] I highly recomment these, well made and they are fused.
fused is very important! These are compact and yeah the wire is not nearly the same size as the battery cables. So here is how you use them.
Hook them up to another vehicle, or battery. Wait 3-5 minutes before you attempt to start, that way not so much current draw at one time.
They are like $20. By the time you buy the wire, clamps etc you havent really gained anything making your own.
http://www.upstart-inc.com/

BTW starter amp draw is not really an issue with jumper cables. The battery acts as a buffer (capacitor also) so the jumper cables dont take the full hit of the amp draw anyway. So big wire is not a must have especially if the cables are fused.

 

[Yammerhead]

Is there some type of fuse or overcurrent device in line with the starter? If there is, size the wire by that value. Can you see a wire size on the battery cables or jumper leads that come out the side?

Now, wire amperages are listed for continuous use. For jumper cables, the duty cycle is very short. The high current is flowing only for as long as you are cranking the starter, which should only be 10 to 15 sec at a crack. This short duty cycle means the wire doesn't heat up as fast as it would in a continuous operation. What this means is if the starter draws 50A while cranking, you could probably get away with a wire that has a published amperage rating of 30A.

The cables that Tork linked to are for re-charging batteries, not boosting. They have a 3A fuse in them they would blow if you tried to crank the motor before the battery was fully charged. Those cables are made with 16 guage wire, which is quite a bit smaller than I would want.

My spider sense tells me that #8 copper would be more than enough to boost your sled. Just a guess though. If it were me, I would match whatever the battery cables are made of.

 

[Sled Dog]

Yammerhead what you are saying is true but if you let it charge for 20 minutes like Tork was saying most of the starter draw would come from the sleds battery. I agree to do a direct boost bigger cable would be needed but then you are carrying bigger bulkier cables.

 

[Yammerhead]

Yammerhead what you are saying is true but if you let it charge for 20 minutes like Tork was saying most of the starter draw would come from the sleds battery. I agree to do a direct boost bigger cable would be needed but then you are carrying bigger bulkier cables.

Yup, you are both right as long as you have a healthy battery. If the battery doesn't want to take charge, then the starter is going to be pulling all of it's power from the other healthy battery via the cables. If you have a frozen or shorted cell in the battery, then the fuse in the cables will blow as soon as you crank the dead sled over. On one really cold day, I was going for a ride with a buddy who has an Indy 500 fulie. We went to start his sled and it was a no go. We openned the hood and could see the battiery was frozen. So we stuck a charger on it, gave it a few pulls, and it started. At first, the battery wouldn't take any charge and when we took the charger off, the sled went into limp home mode. He limped around the yard for a bit and as soon as the battery warmed up, it took some charge and away he went. I was surprised because I always thought once a battery froze, it was toast. Apparently not. Anyway, my point is that in this situation, if it was an electric start RX-1, we would not have been able to start it with 3 amp booster cables. The cables would have needed to conduct the full current draw of the starter (more than 3 amps) I would rather have the bigger bulkier cables an pay the weight and size penalty to have peace of mind.

Just my opinion though......

 

[Tork]

Is there some type of fuse or overcurrent device in line with the starter? If there is, size the wire by that value. Can you see a wire size on the battery cables or jumper leads that come out the side?

Now, wire amperages are listed for continuous use. For jumper cables, the duty cycle is very short. The high current is flowing only for as long as you are cranking the starter, which should only be 10 to 15 sec at a crack. This short duty cycle means the wire doesn't heat up as fast as it would in a continuous operation. What this means is if the starter draws 50A while cranking, you could probably get away with a wire that has a published amperage rating of 30A.

The cables that Tork linked to are for re-charging batteries, not boosting. They have a 3A fuse in them they would blow if you tried to crank the motor before the battery was fully charged. Those cables are made with 16 guage wire, which is quite a bit smaller than I would want.

My spider sense tells me that #8 copper would be more than enough to boost your sled. Just a guess though. If it were me, I would match whatever the battery cables are made of.

Well at least on the 2 strokes and pretty sure on the 4 strokes it goes solenoid to the starter no fuse or fusable link.
Yeah if you dont want to wait that 3-5 minutes (you dont have to wait until it is completely charged) you got to carry a big bunch of wire around which is something I dont want to do but that is just my preference. The battery cable and solenoid to starter is a lot thicker than 8 gauge but I agree 8 gauge would probably work.

But here is another problem. Typical charge rate on these Yuasa batteries is something like 1.6 amps. They do not like a big amp charge rate. That probably shortens the life of the battery.

I mean do what you are comfortable with. My situation is that I keep my batteries charged over the summer. So the plates never sulfate and it will hold a charge to an extent that it will never freeze and the people I ride with do the same. My father in law was buying batteries for all his sleds every year, I got 7 years out of a 97 sled that I just sold last year and the battery was still good.
If you or a friend you ride with dont maintain batteries, big cables are prolly best. For me the recharger cables work fine and it is like 3-5 minutes.

 

[Yammerhead]

Those battery tenders are a really great device. For these 4 strokes that rely heavily on good batteries, it should be the first accessory that an owner buys.

Who ever thought buying a set of booster cables could be so complicated!!