Author Topic: Help I can never get this damn thing to run (Read 3768 times)

blake10722 · « **on:** October 20, 2005, 05:59:07 PM »

Ok so here is the story. I bought a 1992 gsf400 bandit for around 580. it turned over but did not run when I bought it. I bought new carbs as some nuckel head had drilled out the old ones ( I think he was trying to install some type of jet kit) I rebuilt the new crabs but them in the bike and bought a new battery. great the bike runs. my friend killed the battery and charged it with a 1 amp charger for five hours. when he went to take the charger off he arched the battery or hit the frame or soemthing. All I know is that it sounded liek a rifle shot. since then the biek started once teh next day but will not start again. I have fuel and good plugs the carbs are fine. teh problem is that I have spark but very little. the battery is cracked and no good at all. I am gettgna new batery but have a very questions.

so my question is this. do you think it is the battery? I don't as the bike is turning over well and ther is some spark. I think it is either the coils, CDI or a short in teh harness from acid leak. I have bought new coils and am going to put them on along with a new battery. Do you think this will do it or shoudl I start lookign for a CDI box. ? does it sound like it is the CDI they blew? Thanks for any advice or help.

stripes1976 · « **Reply #1 on:** October 20, 2005, 07:43:21 PM »

if you had blown the cdi you would have no spark at all as the coils wouldnt fire! My advice to you is bin the battery and put a new one on! If the battery has had it you will struggle to get a spark anyway!
Until you have a decent battery there is no way of finding out if there is anything else wrong!

in your post you say the battery is cracked?

blake10722 · « **Reply #2 on:** October 20, 2005, 07:58:10 PM »

ok so I just got the new battery and will see what happens. The battery I am replacing did actually crack. I could not believe that the damn thing actually did split along the top and down the side. Must have been overharged. I HAVE BEEN TOLD THAT YOU WILL SOMETIMES GET SPARK EVEN WITH A BAD CDI BOX. also when I went to start the thing the battery was cracked but I did not know and I had it hooked up to my car via jumpers. so don't you think that EVEN THOUGH THE BATTERY WAS CRACKED THE BIKE WAS GETTING ENOUGH JUICE SINCE IT WAS TURNING OVER STRONGLY AND WAS HOOKED UP TO MY CAR? Again thanks.

stripes1976 · « **Reply #3 on:** October 20, 2005, 08:25:25 PM »

the cdi's on these things can be very delicate and jumping from a car can damage the cdi. I would personally make sure you have a good battery before you start.
remove all four plugs making sure you know which lead is which. put the plugs into the leads and check you have a spark on all 4.(this way your battery doesnt take a hard time trying to turn over with the plugs in.
Then the next thing to check is that you are getting fuel through to you engine.Have you checked this? Once you have determined you have sparks and your plugs are clean. check your air filter is clean and your exhaust is blocked/damaged.
what has happened since the bike was last running?

Maniac · « **Reply #4 on:** October 21, 2005, 12:02:26 AM »

First of all, it's not a CDI. It's a Digital Igniter. Whats the difference? One is a microcomputer (Similar to the spark control box in your car), the other isn't.

If your battery exploded, I'd be grabbing a continuity tester and running down the wiring harness. Have you checked your fuses and relays yet? There is an ignition relay right next to the battery, if it's not working then the DI and the rest of the bike won't get proper power. Yeah, it's possible that the Digital Igniter is bad, but I'd think you'd have seen smoke with that kind of pop.

If it is bad, you are going to be fighting an uphill battle to find a new one. There are some posts that detail how to possibly fix them, it depends on whats blown.

Before we start buying stuff to replace ('cause it's expensive), we should be trying to figure out whats bad. Check the simple stuff first. Check the operation of all the switchs, don't forget about the sidestand ignition cutoff switch as well. Best done with a cheap $10 radioshack continuity tester

Racerruss-ducati · « **Reply #5 on:** October 21, 2005, 11:00:47 PM »

Quote

All I know is that it sounded liek a rifle shot.

That was the hydrogen, that your battery puts off when either charging or discharging, exploding from the spark. You and your friend are lucky you didn't get some acid burns, especially in your eyes!!! Quick note on jumper cable safety, always hook the good battery up directly to the jumper cables and the other positive to the dead battery positive and last hook the negative cable to the dead machine away from the battery on a frame or engine bolt. Reverse this sequence once the dead vehicle is started. This will prevent generating sparks around a rapidly charging or discharging battery that is producing a lot of hydrogen. It is also highly recommended to wear safety glasses when working on batteries, they will explode if a spark is generated.

I gotta go with the other guys on fixing the known bad parts first (battery) before guessing at anything else. It is possible the cracked battery has an internal short that can be overcome by a car battery for cranking, but may still be effecting the igniter box, not allowing a hot enough spark. I don't think the electrical system on the bike is so touchy to be damaged by a simple accidental ground by jumper cables. Maybe crossed jumper cables, but not a quick spark like you described. It will be interesting to know what you finally find to resolve it. Keep us posted.

blake10722 · « **Reply #6 on:** October 25, 2005, 12:49:34 AM »

ok so I got a new battery and replaced the coils. still no luck. I am getting spark. but I am not sure if it is enough to ignight the fuel? if it is not the battery and not the coils and I am getting fuel and spraying starter in the cylinders regardeless then it can only be the black box or the plugs. I have shown the plugs to my friends and they say they look fine. they are dirty from the starter fluid but seems to be fine. I got a spark tester and am getting spark up to 20 ( I forgot what the units of distance are) but it is a very thin blue spark. Please help I am losing hope here. damn my friend.

Red01 · « **Reply #7 on:** October 25, 2005, 12:54:50 AM »

Have you run a compression check?

blake10722 · « **Reply #8 on:** October 25, 2005, 01:16:48 AM »

well I sort of have. I have just left the plug in but not screwed in and when I cranked it is poped up and then fell back in. I did not do this on purpose of course. but yes I do believe I have compression. I have decided to go out and get new plugs and then if that does not work I will get a new cdi. I also am working under the asumption that if I have a short the bike will start but that it will jsut drain the battery.

Red01 · « **Reply #9 on:** October 25, 2005, 01:37:53 AM »

Your compression could still be high enough to move a plug, but too low to support a start.

Before you buy a new black box, check the threads on fixing the one you have, or if you feel that's over your head, send it off to Carmo and get it fixed.

blake10722 · « **Reply #10 on:** October 25, 2005, 02:13:44 AM »

well if it is the compression then I am phucked. also what about my question with the short and what about how much spark I should be getting.
Thanks a bunch

Red01 · « **Reply #11 on:** October 25, 2005, 07:21:26 AM »

The sparks look depends some on the style of plug. Not being intimately familiar with the B4, I'll let B4 owners answer that, but thin & blue is not usually good. Fat & blue, or white (thin or fat) will usually be enough to fire. If your compression is good, the thin blue spark may not be enough to jump when in the high pressure of cylinder that's supposed to be firing.

Maniac · « **Reply #12 on:** October 25, 2005, 09:37:58 AM »

Quote from: "Red01"

The sparks look depends some on the style of plug. Not being intimately familiar with the B4, I'll let B4 owners answer that, but thin & blue is not usually good. Fat & blue, or white (thin or fat) will usually be enough to fire. If your compression is good, the thin blue spark may not be enough to jump when in the high pressure of cylinder that's supposed to be firing.

Yep, thats pretty much it right there. A plug can have spark, but it's next to impossible to see how the plug is actually working when inside the engine. If in doubt, replace! They are cheap and I've seen several people on this board (myself included) who dropped good time and money trying to troubleshoot a problem that ended up just being a bad plug or two.

For best results, get all 4 at once. If you can, get a spare set as well and carry them around on the bike with a sparkplug wrench.