Kymco UXV 500 Replacement CDI Box 30400-LEE8-900

[CThacker]

I am having trouble with my Side x Side starting.
Everything has been updated as far as the Engine, however now something seems to be draining the battery when I try to start it up.
It is pulling so much off the battery that the starter isn't getting enough juice and the battery drains fast.
I have eliminated the accessories like the fan and lights, pulled fuses and disconnected their Relays.  Only thing left I can think of to check is the CDI Box or if there is a voltage regulator somewhere.
The CDI Box is CDI Box 30400-LEE8-900 however I cannot find a replacement.  I am thinking maybe a different model number may work but I cannot find a cross reference sheet anywhere.  The single piston timing is good, new starter, it has good gas, new battery, new cam shafts.

Does anybody here have any experience in the CDI's? Again, this is a Kymco UXV 500 4x4 and I am thinking this may be the problem.

Thanks!

[CROSSBOLT]

You may not want to hear this but the Kymcos 300 cc and larger, in my opinion, have marginal starting systems. Stated more accurately, the ECU (Engine Control Unit) stop producing spark when the buss voltage drops below 9.5 vdc. I have measured this with an oscilloscope as well as fooled around with these systems since 2004 which means I have an opinion that seems close to the real truth!

I got tired of my DT300i and UXV500i being so marginal on starting. The 300 got a better battery (shoulda sprung for a Yuasa!) and put a bigger battery in the 500. The Lawn & Garden that went into the 500 has aged out and needs a replacement. Probably get a small car battery next.

The biggest thing seems the sitting doing nothing, parked in the barn and carport is the killer. Ride every day or even once every three days and should be the normal quick start characteristic of Kymco EFI. I THINK that stupid clock is what is sucking the life out of the scrawny batteries.

I am tempted to do several things and eliminate the constant drain of that clock and anything else. A Master switch would do that....

[Ruffus]

@CThacker welcome here!
Echo 100% what CROSSBOLT writes. Had the same experience with bigger KYMCO engines.
My cure was:
-removing all corrosion from ground points
-eliminating "guzzlers" like digital clock, etc..
-additional plus cable from battery to startermotor
-change to a 30 amps LiFePo4 battery

[CThacker]

With my oversized jump pack, it can start so yea maybe it is just a crap design on the battery and ECU....
I think a Master switch may be the best option.  A buddy of mine actually suggested that as well. Kind of like some boats.
I might be able to put multiple batteries (I have spare small ones) in there instead of buying a new larger one.

Heck honestly, I want to sell it and get something better, but who's going to really buy it until I figure this out.  LOL
Thanks for the advice CROSSBOLT and Ruffus!!! I will give it a go and clean the grounds the try the master switch with separate power lines to start it.

Wish me luck!

[CROSSBOLT]

With my oversized jump pack, it can start so yea maybe it is just a crap design on the battery and ECU....
I think a Master switch may be the best option.  A buddy of mine actually suggested that as well. Kind of like some boats.
I might be able to put multiple batteries (I have spare small ones) in there instead of buying a new larger one.

Heck honestly, I want to sell it and get something better, but who's going to really buy it until I figure this out.  LOL
Thanks for the advice CROSSBOLT and Ruffus!!! I will give it a go and clean the grounds the try the master switch with separate power lines to start it.

Wish me luck!

No such thing as "luck," boy! Good, solid, well thought out GUESSES, maybe...! Har, har!

Let us know how you hooked up that master switch!

[Ruffus]

As CROSSBOLT says:
this switch and a grown up battery might be the solution.
For the switch: take one with at least a 150 amps capacity, otherwise it's shortlived.

Since I know my clients, only install something proof like (pls see pic).

[CROSSBOLT]

As CROSSBOLT says:
this switch and a grown up battery might be the solution.
For the switch: take one with at least a 150 amps capacity, otherwise it's shortlived.

Master switch in light aircraft use a starter relay that is rated for continuous activation. On these machines we could do it like in light aircraft and just interrupt the non-start buss that goes to the fuse block which is a 30 amp circuit.