93 fzr 600 electrical issue

[hathaway16]

ok everyone im having a problem with my bike, it randomly wouldn't start one day and i don't know why. i started tearing it apart and doing some testing on it and first thing ive found is none of my plug caps have any resistance in them. ive tested the DVOM i used and it does work. wont even work on the beep setting. i will be testing more tonight. and does anyone know of common problems with these? i remember installing an r6 voltage regulator on it because it was charging at 16 volts.

[Bandon]

Are you saying that there's zero resistance, or infinite resistance? With the "beep" (continuity) setting, with zero resistance, you should hear the tone. With infinite resistance, you'll hear nothing, indicating a break in the circuit, or infinite resistance.

[hathaway16]

Yes infinite resistance(no beep) but after charging the battery it seemed to get spark, apatently the battery wasn't full. But it only runs on two cylinders, 2&3 don't change idle when unPlugged together but 1 or 4 kills it. Will swap coils and test carbs with starting fluid when I get out of work tomorrow

[GreyImport]

Dont forget to check the leads.....unscrew the caps and nip a small bit off the end so the caps have some "new" wire to screw into .

Maybe swap out a "working" lead with a non firing cylinder temporarily .
Swap the plugs around.

[hathaway16]

By leads do you mean the wire from coil to the plug? I'm new to coils on bikes as I wrench on cars all day. I'm going to swap coils and see if the miss moves, if not Cdi box it is or new Plugs but we will see tomorrow

[GreyImport]

Yea......Im just looking at the simpler things first.....and being old bikes anything is possible!

where the lead goes into the cap is, just pull back the little rubber cover and unscrew the the cap itself.
It will look something like this....



Swapping things around is the way to go

[hathaway16]

ya thats what i did in the first place, resistance from the screw part and the part the plug goes into had infinite resistance (no beep) havent checked the other ends, but i did spray starting fluid in the cylinders and it seemed to bog/rev up on all 4 so im thinking carbs but doing more testing soon

[HybridSport600]

This info below should answer any coil problems.
Check that the primary wiring (the small wires attached to the coils) attachment points are all clean and free of corrosion. While you are at this point you can also check the resistance of the primary and secondary sides of the coils with a volt/ohm meter.
Working with one coil at a time, trace the small wires (these are the primary wires), from where they enter the coil back to where they connect to the wiring harness. There should be two per coil (a solid orange or solid gray one and a red/white striped one). Pull these connections apart and clean with electrical contact cleaner if necessary. Protect the connection after cleaning by applying di-electric grease to the connectors. Pull the spark plug wires for that coil off the plugs. Measure the resistance across the wires coming from the primary side of the coil. It should read 1.5 ohms ± 10%. The Yamaha manual says these measurements are made at 68 degrees Fahrenheit (20 degrees Celsius). With those connections still apart you can test the resistance of the secondary side of the coil. Measure the resistance across the two spark plug connectors. This measurement should be 15k ohms ± 10% at 68 degrees F. (20 deg. C.). If either of these readings is infinite resistance or past the ± 10% mark, you probably need to replace the coils.
If the readings are marginal, you still may not be out of the woods. Usually either a coil works or it does not. The spark plug wires which I speculate are, more often than not, the real failure (and not the coils themselves). If an inspection of the spark plug wires shows visible damage such as cracking, checking, badly worn spots (from rubbing against something) or cuts in the insulation, they need to be replaced. Note: Even wires with no apparent damage can have failed. Such damage shows up as intermittent misses while running.
Electricity follows the path of least resistance. If it finds a path where it can arc to the frame or engine easier that going to the spark plug, it will. This path could be through a damaged spark plug lead. This can cause severe damage to the electronic ignition module or physical harm to you and/or your bike.
If the secondary leads are not damaged, there is another test you can do involves pulling the spark plugs one by one, cleaning them and checking the spark.
This is best done by two people and in dim light. One person will start and stop the engine and the other will control the spark plug and make observations.
Remove all spark plugs and connect it back to its spark plug wire boot one at a time. Hold the tip of the plug against a good ground on the engine. IMPORTANT: Be sure this is a good bare metal spot on the engine! Then, with the transmission in neutral, turn the key on and press and hold the start button while you observe the spark. It should be a good fat blue/white spark, and keep the firing spark plug away from the open spark plug hole. The sparking plug could ignite any air-fuel mixture forced out of the engine when you turn the engine over.

[hathaway16]

so i went out and bought 4 new spark plugs, gaped at exactly 30, check every one for spark and they were all pretty strong. after installing it all cylinder 1-3 seem to rev up when i spray starting fluid into them and cylinder 4 bogs down. im going to clean the carbs again and see what it does. also seems like all 4 plugs pulled 1 at a time will cause it to die down now

[hathaway16]

In case it helPs I've been having this problem since I first got the bike, it has always had a weird idle, either at like 800 or 3000. I let the bike idle for about a minute and felt the exhaust pipes, cylinders 3 and 4 were kinda warm and cylinder 2 was hot as hell. Didn't test cylinder 1 because the burn I got from cylinder 2. Oh and I've completely cleaned carbs befor and been cleaning carbs on my sleds for years with great success but pilot screws wouldn't come out they were seized and I need to replace them and the housings they are in if anyone's got a set of them for sale. And don't ever use ur palm to test pipes because I got a burn the size of a golf ball sticking up almost a half inch

[hathaway16]

so i think i figured it out. pulled the carbs apart again and cleaned the crap out of them. almost all of them seemed to have nasty crud in the hole for the main jet that seemed like it was an o-ring that got eaten by gas? do these have o-rings where the jets go in? ive never seen carbs that did and these seemed like they did, so i cleaned them all out and it seems to run better, rode it like 20 miles today in 40 degree weather and topped the tank off with ethanol free gas for winter. and does anyone know the main air fuel screw? 3 turns from shut? thats what they are at and i haven't looked into the service manual to check it. seems to pull nicely through the RPMs with just a slight hesitation at around 7k and idles smoothly at 1500 RPMs. all exhaust pipes are around the same temp now too

[HybridSport600]

Sorry, I should have read your earlier post better, if the exhaust temps are different by as much as you expect. then yes the jets being clogged will cause a lean mixture and can cause most the problems you listed as far as runability, how did the coils check out?

carb parts explosion below...

http://images.cmsnl.com/img/partslists/ ... 7_c6ff.gif

[hathaway16]

I looked at an exploded view of the carbs in the service manual and doesent look like there is one, coils were good. Bike does only have 8600 miles now

[HybridSport600]

good to hear the coils are good, the only o rings on the fzr carbs is on the needle adjusting screws, and the choke valve's. I would look into the harness that supplys the electrics to the coils and the igniter unit, I have seen many that have had overheated connectors, and almost all have the common corrosion on the contacts. May just be a intermitent connection loss, or the ground not tight. i replace all connectors with the weather pak connectors used on auto's. Link provided below. they come in any combination needed, and I would recamend the use of some dielectric grease in there as well.





http://www.ebay.com/sch/i.html?_trksid= ... &_from=R40

[hathaway16]

I'm a mechanic and specialize in electrical so I always watch connectors, the grime build up in the jets was clogging them. Connections look brand new no corrosion and I use the grease on them all, thanks for the info tho, now to rewire my Yamaha sled that got chewed apart by rats!!