Bonneville America Forums Forums Technical Forums General Tech Another cutting out bike...ugh.

My bike has seldom failed me beyond a bad battery....but today...I go to take my friend (who had not ridden a motorcycle in about 30 years, until recently) for a late afternoon ride, he was going to ride on the freeway for his very first time heading over to Washington. He has been practicing a lot and was excited; he has been getting more and more confident around town. We go over the route, some expectations and signals if he has any issues (he has a 78 KZ650). I tell him to just follow me and I'll stay right at the speed limit.
I don't know if my bike got angry that we were under 70 MPH or what. We are moving along fine and then I thought I ran out of gas. It seemed early but no big deal reached down switched to reserve and continued on my way...oooops no...the bike dies a few moments after that. The tack is bouncin' all over the place. I pull over, it starts right back up we start to take off and it dies. After several tries and I realize as long as I kept the revs under 4000 it was fine, but if I revved the motor for a short length of time it would just die, I'd coast wait for the oil light and start if up again. Eventually, I was able to keep it under the revs. we got to where we were going and back home with no more issues. I did try to see if I had pinched the breather hose again. That was my first thought....but the tach would act all crazy right before it would die so I got back and checked the battery it was exactly at 12.8 when running and 12.6 with the key on. I suspect something electrical. Any ideas? Oh and most times when it restarted it backfired.

My friend, by the way said it was more of an adventure than he was expecting. He was just happy we made if there and back in one piece.

OH NO! Not now... especially NOW! I'd send you my spare CDI if I could (because it's a surefire way to rule in or out your existing CDI) but I just lent it to Marty who also has been having problems. Dang! What could it be? Check out connections to both coils... just that. You don't need to pull the tank, just reach under and make sure ALL the connectors on each coil are good. Let's hope it's as simple as that.

Sounds very similar to my problem...turned out to be my coils. Hope you get sorted soon.

seems to be allot of that going on these days. the 4k thing is a bit different though, had the bike gotten wet or anything before the ride? check your fuses too, pull them out make sure there are non on the edge of going (brown burnt spots and stuff)

will the bike stay over 4k rpm when in neutral or just when riding it will die? something could be clogging the main jet? Check spark plugs and wires? Check battery cables and make sure they are all tight. Hopefully someone else will have something for ya buddy.

not good.

I thought my problem was fuel at first but the fact that it just died made me think it was more of an electrical prob, I also remember reading somewhere that most fuel problems are electrical!...Could it be that the coils crap out when the bike is reving harder because of increasing the output? Edmspeedmasters point is good...be interesting to see if it dies when in neutral @4000. Good luck

I'll try revving it in Neutral when I get home and see what happens. I'm sure the neighbors will be pleased.

From what I've been reading, it does sound like the coils. I guess if they overheat they cut out, which in theory should happen if I'm revving it in Neutral, but why I was several miles down the road when it happened before they got too hot and crapped out.

I wondered if it was similar to yours Stephen. Your post was the first thing that came to mind on the side of the road.

If I hadn't noticed the tach, I would have never thought about it being electrical.

The tach pulls info form the coils via the CDI. Makes sense the tach would go nuts if the coils started crapping out.
Coils can still take time to reach a certain operating temp.

Wish I had time or lived closer. Id love to help you with this so it cost you as little as possible.

Think Cascade would let you borrow a set of coils for a few days to test with?

I've been reading how to test them with a multi meter, so I was going to try that tonight. If they appear bad, I'll call Cascade in the morning. They usually have them in stock, I've been told. Marty has offered to send me his spares along with Keiths ProCom to check if need be. I thought I may ask Laurie if I can borrow hers to check if possible.

My real issue is I'm on vacation as of Tuesday the 8th and will be back one day before I'm supposed to leave for your house.

What should our coils read? I've read 3-5 ohms for most bikes, is that correct?

They may read fine until they get to temp then they might crap out.
Take the spares from Keith and Marty. At least you'll have them on hand in case one or the other really craps out and you'll be able to return the unused parts in a couple weeks.

Have you bypassed your side stand switch? That might be worth a quick do just t be sure.

My rear brake light wasn't activating due to some water and crud that got under the boot and disintegrated the connection. Luckily it was a part the dealer had on hand and it was cheap. Just goes to show don't rule out the simple stuff.

Hey Brent... I'll leave it up to you and Marty if you want to borrow my Procom which you are most welcome to. Not sure how soon it would get to you what with the border and customs and such.

Thank you Keith,

Marty PM'd me with that same idea. I told him to go ahead and send it. It certainly wouldn't hurt to have with me and I can bring it back to you. I'm taking the bike in to have the coils and igniter box coil? replaced tomorrow. The mechanic who has always worked on my bike said coils have about a 6 year life span.
They know I need it for the trip. So that is good. It's nice to be on good terms with your shop. Hopefully they know how much I appreciate them.

Brent whats the update man, you good?

My bike cut out and died a few years ago and I thought I was stuck along the road. Turns out it was the 30 amp main fuse. The fuse was fine but a little corrosion had occurred between the fuse and the fusebox. I slid it in and out several times to clear the corrosion and it was fine. When I got home I put some dielectric grease on all the fuses.

Thanks Larry, yep, I bought some new fuses just in case and went through each one and replaced anything dodgy looking. Though all tested well.

No news yet, I'm supposed to find out tomorrow. Thankfully, they know I have a deadline. I'm glad I have a good relationship with my dealer. The same mechanic has been working on my bike for serveral years. He told me there should be no reason he can't get it running.

We'll see....

I'll update tomorrow.

Brent,tomorrow was yesterday,whats the scoop?

Please say it's good news.

Paging Brent.....Paging Brent

Maybe he's on his way,or walking home

I've been on vacation with the family...I pick up the bike tomorrow. They say they got it sorted out. I was on the road but the explanation was a bit vague. I'll know tomorrow morning (Tuesday). I will see if I make to Z's tomorrow night.

I got the package Marty. Thank you.

good to hear Brent, see ya soon.

I rode it home this morning, and it seems good. All in all even though the battery was reading good it was somehow discharging at higher revs. A new battery sorted it out. That's three in three years. I'm happy it's acting normally again.