help diagnose this | GTAMotorcycle.com

help diagnose this

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Dsquintz

Well-known member
ok so coming home on friday I got caught in the rain storm and parked my bike about 5 minutes from my house while it blew over. when I started the bike back up it wanted to stall on me. once i got going the bike was real jerky and i felt a huge loss of power. every couple minutes on my slow ride home i would feel power come back on. This led me to think that due to the severe wetness that the bike was misfiring on 1 or more cylinders.

So I figured because it's wet maybe the wires arent the best shape and should be replaced. after letting the bike sit and hopefully everything dried off since friday night I tried starting it today and it would fire up but was bogging out and when i would give a little throttle to keep it from stalling out i could tell it was still wasn't firing on all 4 cylinders.
I havent had an opportunity YET to check the plugs/wires to make sure none are loose and the wires aren't cracked. but im trying to figure out what else I should be looking at once i get the tank off if I cant see anything wrong with the plugs/wires.

Thanks :)
 
You know that once u drop your bike it will run rough, right?

Just run it for a bit and it should settle itself out.
I remember when I dumped my bike I had to ride home with a rough engine and busted knees. I even felt the blood trickling into my jeans
 
The bike never dropped. Sorry to clarify I was waiting for the rain to stop where I said "blow over"
 
at some point, we're kinda gonna need to know what sort of vehicle we're talkin bout here...

You hinted that it's a 4 cylinder... so that narrows it down to a few thousand bikes/yrs.
 
Not sure if this wil help, i don't know your bike, but,...something easy...
Run the bike in the dark and watch for jumping / leaking sparks from your ignition leads (may need to rig up a fuel sytem of sorts with the tank off....a long feeder hose to the tank on a stand / shelf beside the bike)
This might help identify exactly where the ignition leak is....assuming it is an ignition leak from the high tension leads / coils.

I've used this method quite a few times on various vehicles and i like it cause it shows me the exact location of the leak which enables me to fix just that only...(not replace all leads and coils)
 
check under the cover where the pick up coils are, you might find water in there, then check all connections igintion related.
 
Thanks for the replies. I'm going to get into it tonight and see where I sit with it. From the sounds of it last night I may have to replace a coil. Had it running last night and it seemed to only be firing on 2 cylinders until it stalled out.
I hope it's not my coils. shop I called has em on backorder for 2-6 weeks :s
 
Doubt it is the coils most likely condensation. Pull each spark plug wire from the plugs and blow them dry and the put a good dollup of dielectric grease inside the boot. This should fix it.
 
taximan62 said:
Doubt it is the coils most likely condensation. Pull each spark plug wire from the plugs and blow them dry and the put a good dollup of dielectric grease inside the boot. This should fix it.
Click to expand...

This.

Don't stop at just the spark plug wires though. Whenver i have bikes apart or even semi-apart i always pop every connector i can and put in some dielectric grase then reconnect everything. It does wonders to make your bike a bit more weather-tight.
 
There should be a drain hole through the side/front of the head leading to each spark plug. Over time bugs crawl into the holes, turn crispy the next time you ride, and eventually plug the drain hole. Then when it rains and water seeps into the spark plug recess, it fills up rather than drains. The spark plug will be drowning, and that cylinder will usually start to cut out. Make sure the drain holes are clean, and use dielectric grease on the spark plugs.

Edit: Do this before you pull the plugs, otherwise you may end up with a puddle of water draining into your cylinder when you turn the plug out.
 
It's probably wet plugs. Pull them and dry them and it'll run fine.
 
So I got into it last night with my buddy whos a mechanic. before he came i tore into it myself and noticed the plug well for cylinder 3,4 had puddles of water in them. when I pulled the cap off the plug the amount of water in #3 was almost to the top of the spark plug. took some compressed air and blew all the water out of every cylinder and just wiped off the caps and ran the motor hoping the heat would dry things out. didnt work lol. so we got into it a bit more and started pulling plugs out. looked like #2 wasn't in the best shape and had some black gunk on the leads going into the head. didn't seem like gas so we wiped it off and checked the wire connection to the cap. the wire actually pulled right out of the cap rather easily which didn't seem right and the ends of the wire were a little black.
We left it at that and just put the plugs/wires back in and going to tackle it tonight.

on katriders.com someone suggested to cut about 1/2" of the wire to get some fresh wire going down to the cap lead. there was also a clicking noise so we think something is grounding to soon. I think it's only missing on one cylinder(sounds like #2) now because when everything was dry it was still running funny but when we wet #1 and #2 wires/cap/coil it bogged down. combined with the loose cap connection on #2 i think this is where the problem lies or at least part of it.

On the topic of the drain you mentioned. Where about is this located on the cylinder head?
 
Dsquintz said:
On the topic of the drain you mentioned. Where about is this located on the cylinder head?
Click to expand...

I can't tell you exactly (I don't own a kat, but all bikes I've owned have had drain holes, and I had your exact problem with one of them), but being an inline 4 with a forward cant to the motor, I'll say they're on the front side of the head so the drain can be on the low side. There should be one for each spark plug hole, so look in an area perpendicular to each spark plug maybe an inch or two down from the top. The drain hole would roughly line up with the bottom of the spark plug well (obviously, otherwise it wouldn't drain the water). They're generally the diameter of maybe a pencil, or even a bit smaller. You may have to look closely between the ridges, etc. in the head to find them. Some pipe cleaner is generally used to clean them out, or you could use compressed air to blow them out. Keep your plugs in, clean the drain hole, blow any crap out of the spark plug well with compressed air that might have ended up there before you remove the plugs and add dielectric grease to them.

Edit: Found this at katriders.com: http://katriders.com/vb/showthread.php?t=113125

It's f'n impossible to get a decent picture of the hole! It's very small, and in between two ridges on the head. I took 3 pictures hoping that one of them would show it clearly, but none of them do. If I have the tank off again sometime soon, I'll just pour some water in the plug well and take a picture of it coming out. Anyway, if you really want to find it, just shine a bright flashlight at the head, right where the exhaust port is and you'll see it. It's about 1/16" or so.

Quote:
Originally Posted by 1BadSvt
Mine does this also. I had no idea there was a drain hole. How does it drain? I just do see how it could i can't wait for the pics!

If your plug wells are clean, you can see it inside the plug well towards the front. That little hole leads out the front of the head, so it can drain as needed.
 
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Ya I found the drain holes and blew it out best I could from the plug well.

Turns out the wires on 3, 4 were grounding to something in the engine causing the misfire. Right now IRS running on all 4 with some careful placement. Didn't bother checking 1, 2 since it was 10pm last night and I was exhausted. I'm wondering if there's anyway to patch the wire from the exterior to help preven this in the future. Maybe wrap some rubber hosing around the wire?
 
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