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Hooking up a capacitor on the DRZ400SM

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O.K. I'm having a brain fart I believe. All the starter hardware is off (wire harness to battery & starter, relay, starter, one way bearing off mag). Hooked up a Trail Tech 56-000 uf capacitor in line. Pos to +, Neg to ground (grounded to motor) but no spark:excuseme: Seems pretty simple, what the :ride: am I doing wrong ?

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Key and kill switch are on. No picture, sorry. Hooked the capacitor directly to the Pos cable going to the regulator/rectifier, ignition switch, speedometer and Neg to ground, ground goes right to the engine case.

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What am I missing here ? There is only 1 Pos cable and 1 Neg, what gives. No juice!!!!!!!

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Everything is hooked up, all I did was pull the battery, the starter relay & the wires going from it to the starter and the + side of the battery, the starter and the one way bearing. Put the capacitor in place of the battery and ..........................................? Nothing ?

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You're not going to have any juice in the capacitor until the bike is running to charge it first. Did I miss something here? :ride:

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You're not going to have any juice in the capacitor until the bike is running to charge it first. Did I miss something here? :ride:

He didn't say but he must have installed the kick start kit.

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Yeah, I got that part, thanks! :ride:

I just read it like there's supposed to be voltage on the capacitor as soon as the capacitor is installed; that's not the case.

The OP needs to check that the stator is putting out voltage, and follow the voltage through the wiring diagram until he finds out where it stops. Could be something mis-wired after the mod, could be a bad rectifier/regulator, kill switch, broken wire in a connector, loose connector (pin to socket), etc. Might want to disconnect that capacitor, check that there's no voltage on it, and then check that it's not internally shorted (ohms setting, AFTER checking that there's 0V on the cap; the ohms should read low, then go up as the cap charges from the ohmmeter battery, or just read some non-zero number depending on how much current the ohmmeter pushes on ohms readings...). If the cap is shorted, it'll pull the 12v to ground and the bike won't run.

Edited by davidl9999

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I didn't follow exactly but in the process of removing the battery and the un-used wires and cables - is the RR neg still connected to chasis ground? I would put the cap between the RR Pos and Neg (just like the Kickk start model) then assure the neg is also connected to the chassis ground. Red and orange wires all stay in place to the CDI. Should work.

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Alright, thanks for the response's. Had to leave for awhile with the kids and get autographs (SX in SF this weekend). So here's the deal, put the kick starter kit on the bike, took off all the starter related stuff. There was 2 red pos wire's from the battery, 1 goes to the relay and 1 goes to the regulator/rectifier, ignition switch and speedometer. There are 2 black ground wires, 1 goes to the engine case the other ties in all the other electrical things, horn, lights, etc, etc. The only wires I got rid of were the 1 red pos wire from the battery to the starter relay, the relay, and the wire from the relay to the starter. The 2 pin terminal connector for the starter relay is unplugged. At this point I took the pos terminal (regulator/rectifier, ignition switch and speedometer) and put it to the pos side of the capacitor. Took the neg terminal (goes to engine case) and put it to the neg side of the capacitor. No spark, if I just hook back up the battery, spark:banghead: I know its a brain fart, I just cant see it. What the :lol: am I doing wrong ? Thanks for all your help guys !:ride:

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Does the bike start without the battery connected (and without the capacitor connected)? If yes, then there's a problem with the capacitor (shorted). If no, then for some reason, your ECU (CDI) is looking for 12vdc in order to run. Not sure why - since the 2000 and up "E" had 12vdc to the ECU and the S and SM don't have that same wire - at least according to the model's wiring diagram, and because the charging coil should supply enough voltage as soon as the bike is kicked over - even if the engine doesn't fire.

Have you looked for voltage on the red + wire to the capacitor and voltage to the rectifier/regulator when the bike is kicked?

Another way to look at this is if the bike starts with the battery connected and you remove the battery and the bike dies, then the ECU is dependent upon 12v being on the red wire (which connects to the orange wire in the ignition switch if I remember right) and your charging system must not be working.

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Yea you need to do some basic troubleshooting to verify the stator is charging the battery. If the bike is running off the battery only then obviously it will not run with the battery disconnected. Put the battery in and run the bike and check if the voltage on the battery comes up.

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Just an FYI....

I put a cap in a street legal XR. It uses a 12v CDI like our DRZ's do. If the cap is dead (after sitting) I have to kick the bike hard a few times (key off) to get a surface charge in the cap so the CDI will fire the plug. Sure, the bike will run without the cap... but if you can't kick it hard enough to produce 12v instantly... then you have to get a charge in the cap first.

2nd FYI...

Most dirt bikes with a kick only starter normally run a high voltage CDI (+300v) and it's easy to get enough power (+100v) out of the source coil on a kick to make it fire. They also normally have separate lighting and ignition coils in the mag.

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Just one more thought to throw in. Is that capacitor polarized. Does it have a + on one side and a - on the other? You may want to check polarity.

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I hooked the battery back up and started the bike, pulled the + off the battery and it died. According to my manual (only checking the yellow wires from the alt) ohms should be between .5 and 1.25, I'm getting between .2/3 & .4 Started the bike and checked volts (again yellow wires only) and at about 5,000 rpm I'm showing a high of 18v and a neg of about the same depending on the wire combo I'm testing. Sounds like I need a new alt/stator ?

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