That @#$%^&!!! KZ650!

Before I got my Dyna 4 ohm coils I was using Kaw 4 ohm's. I was going to my daughter's. stopped to give the bike a bath. Bike fired up and ran great until about 50 miles just at Chaparral when it started cutting out. I limped in and it cleared up. Checked the plugs, they were fine so I continued on my way. Did it again but when I'd slow down, it would pick back up. I kept going, pulling leads, it clearing up over and over. It would run good then start this SHT again. Finally made it there and pulled the coils. I carried a spare just in case. I found some water had made it into the HT lead on the coil itself. The wire end had green crap in it. I cut off 1/4", put them back on and ran them until I got my Dyna's.


Usually it's something stupid like that.
Steve

swest wrote: Before I got my Dyna 4 ohm coils I was using Kaw 4 ohm's. I was going to my daughter's. stopped to give the bike a bath. Bike fired up and ran great until about 50 miles just at Chaparral when it started cutting out. I limped in and it cleared up. Checked the plugs, they were fine so I continued on my way. Did it again but when I'd slow down, it would pick back up. I kept going, pulling leads, it clearing up over and over. It would run good then start this SHT again. Finally made it there and pulled the coils. I carried a spare just in case. I found some water had made it into the HT lead on the coil itself. The wire end had green crap in it. I cut off 1/4", put them back on and ran them until I got my Dyna's.

Usually it's something stupid like that.
Steve

I tried heating the coils and the ignition with my girlfriend's hair dryer. She wasn't happy about that! Didn't notice any difference.

I've decided to start at the top/beginning and work my way down. The tank looks like crap, and needs to be addressed, regardless, so I've pulled it off and I'm going to treat it with muriatic acid. I've ordered a new cap, and have a line on an NOS petcock.

Once the tank, fuel cap and petcock are resolved, they can all be eliminated as causal. Then I'll see where I stand.

Someone on KZ650.info said Dyna Green coils were for CV carbs, only, and would "drown" a bike with pumper carbs. I've never heard that before. I've asked him to elaborate.

seanof30306 wrote:
I tried heating the coils and the ignition with my girlfriend's hair dryer. She wasn't happy about that! Didn't notice any difference.

Sounds like my wife. I haven't seen a difference between happy and mad for years.

I think she just must be happy being mad. :laugh:



Sorry, couldn't resist.

GPzMOD750 wrote:

seanof30306 wrote:
I tried heating the coils and the ignition with my girlfriend's hair dryer. She wasn't happy about that! Didn't notice any difference.

Sounds like my wife. I haven't seen a difference between happy and mad for years.

I think she just must be happy being mad. :laugh:



Sorry, couldn't resist.

Yup. A guy my age knows there are two responses in any situation:

a) "You are ABSOLUTELY right, Honey".

or

b) "I NEVER want to have sex again".

seanof30306 wrote:

swest wrote: Before I got my Dyna 4 ohm coils I was using Kaw 4 ohm's. I was going to my daughter's. stopped to give the bike a bath. Bike fired up and ran great until about 50 miles just at Chaparral when it started cutting out. I limped in and it cleared up. Checked the plugs, they were fine so I continued on my way. Did it again but when I'd slow down, it would pick back up. I kept going, pulling leads, it clearing up over and over. It would run good then start this SHT again. Finally made it there and pulled the coils. I carried a spare just in case. I found some water had made it into the HT lead on the coil itself. The wire end had green crap in it. I cut off 1/4", put them back on and ran them until I got my Dyna's.

Usually it's something stupid like that.
Steve

I tried heating the coils and the ignition with my girlfriend's hair dryer. She wasn't happy about that! Didn't notice any difference.

I've decided to start at the top/beginning and work my way down. The tank looks like crap, and needs to be addressed, regardless, so I've pulled it off and I'm going to treat it with muriatic acid. I've ordered a new cap, and have a line on an NOS petcock.

Once the tank, fuel cap and petcock are resolved, they can all be eliminated as causal. Then I'll see where I stand.

Someone on KZ650.info said Dyna Green coils were for CV carbs, only, and would "drown" a bike with pumper carbs. I've never heard that before. I've asked him to elaborate.

Someone on KZ650.info said Dyna Green coils were for CV carbs, only, and would "drown" a bike with pumper carbs. I've never heard that before. I've asked him to elaborate.[/quote].....HORSEHOCKY :woohoo:
I have 33mm Mikunis on mine and the bike hasn't drown yet in 20 years. I'd still like to see pics of the plugs.
Steve

I do think coils as well as the symptom (loss of power) appears to be drooping two cylinders. To be satisfied, just get both new, that rules out that problem in the future. 2nd, you may find phosphoric acid better than muriatic as it is less caustic and easier to dispose. Also if left too long the acids will expose every rust pinhole you ever had in the old tank. I used KBS Gold Standard coating and the stuff was great. R

rrsmsw9999 wrote: I do think coils as well as the symptom (loss of power) appears to be drooping two cylinders. To be satisfied, just get both new, that rules out that problem in the future.

Man, I absolutely HATE the idea of replacing the coils in the hope that MIGHT resolve the issue.

Spark plug caps can be bad too. Check for corrosion on the ends of the leads and you can bypass them with a paperclip while testing. I'll ask again, pics of the plugs?
Steve

Well coming up the 15 on my way to my daughter's I went on reserve. It took forever for it to recover. I opened the gas cap while riding and that helped but still it was starving for gas. I stopped at the local dirt bike shop and got two new fuel filters. Shoulda done that last month. And cleaned out the vent. "Can't talk to you without talking to me". :lol: Clips soon.
Steve

seanof30306 wrote:

rrsmsw9999 wrote: I do think coils as well as the symptom (loss of power) appears to be drooping two cylinders. To be satisfied, just get both new, that rules out that problem in the future.

Man, I absolutely HATE the idea of replacing the coils in the hope that MIGHT resolve the issue.

Swap the wires over on the coils, if the problem swaps over to the other 2 cylinders, you'll know its the coil...

I really should have changed the filters when was I down the hill.
Steve

UPDATE:

In our last episode, I'd decided to start working from the top down, starting with the tank.

I found a new cap on ebay for 38 bucks, so I got one.



Next I pulled the petcock. The strainer was all clogged up with crap. Got Turbo Rick to rebuild the petcock. He said the spring was bad. It's smooth as silk now.



The crap in the strainer was tank coating that was coming off. I needed to not only clean out the rust, but to strip off the old tank coating, too. I treated the tank with muriatic acid twice. Then I cleaned it out twice with acetone. Finally, I put the Red Kote to it.

The Red Kote directions say it should cure in a day, or so, but, if you can still smell it, it's not cured yet. I let it cure for nearly a week, setting it out in the sun every day. I could still smell it, but I figured if it ain't gonna cure in a week, it ain't gonna cure.



I put the tank back on the bike, and replaced the fuel filter. The old one was a lot harder to blow air through than the identical new one, so there was definitely a problem there, too.

I put gas in the tank, and she fired right up. I gave her a good 5-minute warm-up, and hit the road.

I slowly worked up in speed till she was wide open. I held it there for a good 5 miles. No problems. I then put her on the highway and rode 40 miles at 5,500 rpm. At least, I think it was 5,500 rpm. My Bob Harrington Z-Resto-rebuilt tach bounces from about 4,500 to 6,500, so I just kinda round it off. The speed was 75. At least, I think it was 75. My Bob Harrington Z-Resto-rebuilt speedo bounces between 65 and 85, so I just kinda round it off.

She ran like a champ. The only thing I noticed was, after 40 miles at 5,500 rpm, she idled at about 2,800. After about 10 miles of around-town riding, it started to fall, but it was a good 20 miles before she was idling at her normal 1,400 rpm..

I took her out again last night. She ran well, with the exception of an intermittent flutter while riding down the highway at 4,000 rpm. At least, I think it was 4,000 rpm. My Bob Harrington Z-Resto-rebuilt tach bounces from about 3,500 to 4,500, so I just kinda round it off. It's real steady at idle, though.

Anyway, as soon as It started, I headed home. Long experience has taught me to get that @#$%^&!!! KZ650 to the barn when she starts acting up.

I'm thinking there might be a little tank lining-gunk left in the carbs. I've had one other thought, though. It seems odd to me that there was no fluttering on Tuesday, but it did it on Wednesday. I considered what might have been different between the two nights. I have pods on her, and the wind was really blowing last night. I wonder if the intermittent fluttering I experienced could have been a stiff crosswind blowing across the pods and leaning the mixture out?

It's even windier tonight, so I'm not going to test it out tonight.