Starter Update

[mtotguy]

Just curious but why not replace the negative cable also? Or is the negative cable a larger gauge to begin with?

Because the negative cable is very short compared to the positive. It grounds to the chassis. Then the entire chassis and everything bolted to it (engine and starter) are grounded.

 

[titanrcr]

Because the negative cable is very short compared to the positive. It grounds to the chassis. Then the entire chassis and everything bolted to it (engine and starter) are grounded.

I thought the ground wire was also a long cable. I may upgrade my wire also, original is #4 gauge.

 

[yamahaguy]

In DC electronics the electrons flow from the negative side to the positive side. Even if the negative cable is slightly shorter It requires both a negative and positive cable to make a complete circuit. If the gauge of the cable is truly undersized for this application then both should be changed out

 

[mtotguy]

I'm not an electrician by any means but this is the way I understand it... The problem here is voltage drop. Voltage drop occurs over the course of any circuit. The longer the run, the more the voltage drop. Larger conductors have less voltage drop over the same distance than smaller conductors. The chassis makes for a very large conductor. So there is less voltage drop on the negative side due to the good chassis conductor. On the other hand the positive side does not have the good conductor that the chassis provides to the negative side so the cable needs to be larger. Maybe??? I know that among the car builders I associate with the practice is to use a very large positive cable if there is a long run from the starter to the battery.

 

[yamahaguy]

I totally agree with you the chassis or motor does make for an excellent conductor But you still need a cable from the battery to the chassis grounding point. I'm not bashing what you did I think it's an excellent idea I just believe that both cables should be changed If this is truly a under sized wire issue.

 

[mtotguy]

Yeah like I said I'm not an electrician. I guess it is possible that there is some improvement to be had by changing only the positive cable. Changing both might result in an even greater improvement. Or it's entirely possible that my improved starting has nothing at all to do with the heavier cable and everything to do with the EVO reflash.

 

[yamahaguy]

Yeah like I said I'm not an electrician. I guess it is possible that there is some improvement to be had by changing only the positive cable. Changing both might result in an even greater improvement. Or it's entirely possible that my improved starting has nothing at all to do with the heavier cable and everything to do with the EVO reflash.

We have two 2015's, Maybe I will do a cable upgrade on one of them. Would be a good side by side comparison.

 

[bbquadrider]

One cable would help lower the circuit resistance but I would have like to know the original voltage drop as to how much it helped

via big bad phone

 

[mtotguy]

One cable would help lower the circuit resistance but I would have like to know the original voltage drop as to how much it helped

via big bad phone

There's the explanation! The larger positive cable covering 5 feet of the circuit lowers resistance in the entire circuit. Less voltage drop. Like he says though...since I didn't check voltage before and after we don't know how significant it is.

 

[bbquadrider]

I may do a drop on mine...curious now lol

via big bad phone

 

[cannondale27]

Me too. Keep forgetting.

 

[swampcat]

Me too. Keep forgetting.

Hey while you are forgetting things can you post up the diagnostic side of the gauge ? Sorry about the starter cable issue, all the Cats of this same design all start.

 

[cannondale27]

Hey while you are forgetting things can you post up the diagnostic side of the gauge ? Sorry about the starter cable issue, all the Cats of this same design all start.

Yes. Sorry. No riding plans this weekend just putting it back together so will get it done.

 

[cannondale27]

I have to disagree with your opinion on this. I'm guessing you are on the original ECU flash? What I have experienced is a kickback from too much timing advance. Engine cranking and comes to an abrupt stop. As your explaining a missfire of one cylinder and failure of the next cylinder to fire on it's power stroke what is causing the engine to come to an instant stop? In that situation the engine would just continue to crank, no reason for it to stop cranking. If I knew that the new ignition module from Dynotec was capable of altering the timing below 500 or 1000 rpm I would go ahead and retard it a few degrees just for starting and leave everything else the same. Maybe someone with the module could try this so we would know whats really going on. Also keep in mind that just because an engine fires a few degrees BTDC does not mean it will detonate or knock.

If ignition timing were to far advanced why would they start and crank fine most of the time? The mapping is to lean at startup on some sleds. Now don't get me wrong here. I can say some sleds the timing very well may be off or change as you are cranking because of some glitch in the programming. It would be interesting to data log a bad starting sled. And to answer your question. I have the 15 reflash in mine and have never had a kickback with 14 or 15 flash. But the sleds definitely vary in run quality and that is a issue Yamaha needs to address.

 

[Curtis Chambers]

There is no zero awg (gauge) in Canada anyway. Could be 1/0 here don't think you will see any voltage difference in about 15-20 feet at 12v at this size of wire