igniter box vacuum hose

[forestfarm]

Could someone explain the operation of the igniter box and where it gets it vacuum supply?I am having some intermittent issues with poor performance which i thought was a carb problem and issues with high idle rpm and the bike was maintaining rpm after the throttle is released but when i disconnect the vacuum line to the igniter box my performance problem is present all the time but the high idle issue is gone and the rpms no longer stay up high when the throttle is released.I want to trace back the vacuum line to it and see if i have an issue there before i swap out the box with another igniter box.Any info would be helpful.At this point i am certain its not a cable or idle screw adjustment problem.It is directly related to the igniter box and/or its vacuum supply.Thank you

[Avidrider62]

Wow, welcome to the issue I had/have with my 87 with a 95 engine. The vacuum line comes off number 1, left carb. You'll see the vacuum port , bent upwards. I ran the bike with the hose off and on. Everyones said " you have a vacuum leak". Well, no I didn't, verified with acetalyne gas. After warmed up, rpm's hung high. Cold engine, it needed the CDI advance. So, rolling down the road, I'd reach down and disconnect hose. Performance a little loss, but no more rpms' hanging when clutch pulled in.
I even used my 1248 ignitor from my other bike, no change. Here's what I did. I put a vacuum tee between the filter/valve and ignitor. On the t branch, a little hose and a short dry wall screw (coarse thead). This allowed less vacuum, just enough to be happy.
I bought the $30 valve, removed the vac "t", it seemed to help alittle. It hangs, but drops slowly. Carl Leo was scratching, tying to fig this out. I think some engines, after a quite a few thousand miles, develope diff vaccums. I have a picture of what I did, pm me with email address, I'll send it along.

[HarryL]

My 03 Voyager did the exact same thing. It had a high rough idle which would only idle normal when I would pull the vacuum hose off the ignitor. Carl Leo also advised me to add an adjustable vacuum T to limit vacuum to the ignitor. I used a small plastic adjustable valve from my old vacuum carb sync set and was able to adjust the vacuum to idle normal without losing any performance. I've been running that way for over a year now.

Harry in SA

[Lucasind]

why not post it here....so we all can see

[ekap1200]

Not sayin this was the cause , but I had one in here with the same issues and it turned out to be the sync was Way Off. Just sayin.
Gene K.

[Avidrider62]

Yes, bad sync can do it. I balanced both bikes, same way. So I ruled that out. Posting pics here, I hate it because i can't upload from computer, photobucket is in my means, just a PITA to me.

[Lucasind]

Yeah.....photbucket is a PITA............but after ya get used to using it .....it goes faster and faster to make a photo feature post !.....................tony
( heck ...I even made a recent post ,using tinypic)

[forestfarm]

Thanks for the replys.When I disconnected and plugged the vacuum the vacuum line to the igniter,my warmed up bike no longer had the high wandering down to where it belonged idle.It was like it should be.open the throttle rpms up,close throttle rpms down.But,when riding the bike it had horrible performance,it was like I lost a cylinder.i will try the leaking t connection after I trace the vac line back to the carb.I would like to try another known good igniter box but I have no guarantee the boxes for sale on ebay are any good.Most of the bikes they part out look really nice.Perhaps what took them off the road is this same ridiculous issue.When my bike is cold it runs fantastic,pulls strong through all the gears.Once it warms up it starts intermittent engine stumbling and the rpms stay way up high between shifts.i would really like to know the cure for this.My bike has a lot of good miles left on her,looks fantastic.I cant wait to get it sorted out.I rode it 150 miles last Sunday and I expected it to die on the road at any second,we limped it home.It wouldn't run in 5th gear for more than a few seconds before it started stumbling,had to downshift and get the rpms up high and it would clear up intermittently.it is hard do describe but it just totally takes away my confidence it it.I need to get it sorted out.If anybody has a known good igniter box they would like to sell or loan to me for troubleshooting purposes please pm me.Thanks in advance

[Avidrider62]

Also, ignition coils fail on demand, meaning, higher rpm's. At least in cars they do. Another CDI, ignition box won't change it. I have 3 extra to work with, still no difference

[Avidrider62]

Also, these bikes has had bad ignition switchs. The wires get pinched, cut, or shredded at the neck of the steering column. That could cause intermittant power loss.

[chevyman1]

Yes, bad sync can do it. I balanced both bikes, same way. So I ruled that out. Posting pics here, I hate it because i can't upload from computer, photobucket is in my means, just a PITA to me.

What kind of sync gauges did you use, if you used the one with 4 separate vacuum gauges on it make sure that there isn't a bad gauge.

[forestfarm]

I used the Motion Pro carb synch tool.I correctly calibrated it prior to use per the instructions.I was very methodical in my approach to this task.I am a toolmaker by trade.Are your spare igniter boxes proven to be good by being run on another motorcycle?I have the manual and it has a page on testing the box with an ohmmeter across several of the pins,there is a corresponding chart as to what the value ranges are on good unit.There must be a way to verify the correct operation of the vacuum sensing mechanism on the igniter but I don't know it yet.Im sure there is somebody out there with intimate knowledge on the subject,as these boxes are on all Kawasaki 1200 motors.I will email a contact I found in Florida who has a carb rebuilding service for the Concourse bikes.Maybe he has seen this same problem.Thanks

[Avidrider62]

Yes Chevyman, Motion Pro, paid about $80 shipped.

[Avidrider62]

[forestfarm]

I like the picture .I will definitely give it a try .I could install the tee then make a plug with a small diameter hole ,will start at .03 instead of a sheet rock screw.The price of a new unit is pretty steep at $540.Im afraid to buy a used unit from an ebay parts cannibal.It could very well have the same issue.It has to be with the box itself.I don't see how the bike could be making too much vacuum for the igniter requiring a controlled leak to make it behave.Its all part of my Voyager learning curve.

[Avidrider62]

Steve from Shudabeen Engineering started this repair awhile back. He used a carb small pilot jet. A heavy grade drywall screw allows air in, ie..less vacuum. Our small pilot jets are about the same. As I said, I have 3 other ignitors, trying to do a process of elimination. All test pointed back to the engine vacuum. My 2 voyagers, have 49k and 55k miles

[forestfarm]

mine has 46k miles.Its my first 4 cylinder Kawasaki.My last was an H1 triple in high school.The voyager is a big bike but it has incredible power and smoothness.I will make my own pilot jet out of brass tomorrow night to see what kind of change I get with this setup.I will let you know.If it works out I will send you one so you can put that screw back in the box.I did email Steve a description of my bikes operational quirks but have not yet heard back from him.

[Avidrider62]

I spoke to Steve, he's telling me idle curcuit passeges can be clogged, causing rpms to hang when in neutral.

[forestfarm]

Thanks.I will pull them off and go thru them.Im to check the air valve tomorrow morning to ensure that its opening and closing.Im not so sure if it has any effect on the performance but its something I need to rule out as a culprit.I tried the leaky vacuum hose trick to the igniter today with a .03 vacuum leak.The cold engine would hardly stay running even with the enrichener on .I yanked that right off and connected the hose and it started right up fine.The rpms don't hang when the bike is relatively cool.By the time I get out on the highway for a few miles is when it starts its problems.If I don't get anywhere with checking the air valve and its plumbing I will probably pull the carbs next week.I wanted to flush out the cooling system,looks to be filled with coffee with cream.I also bought new brake pads.They will go on too.Then I will do the carbs as I must wait a few days for the kits to arrive.I was going to send them out but I shouldnt have any trouble doing them myself.Thanks for the info.

[forestfarm]

Thanks.I will pull them off and go thru them.Im to check the air valve tomorrow morning to ensure that its opening and closing.Im not so sure if it has any effect on the performance but its something I need to rule out as a culprit.I tried the leaky vacuum hose trick to the igniter today with a .03 vacuum leak.The cold engine would hardly stay running even with the enrichener on .I yanked that right off and connected the hose and it started right up fine.The rpms don't hang when the bike is relatively cool.By the time I get out on the highway for a few miles is when it starts its problems.If I don't get anywhere with checking the air valve and its plumbing I will probably pull the carbs next week.I wanted to flush out the cooling system,looks to be filled with coffee with cream.I also bought new brake pads.They will go on too.Then I will do the carbs as I must wait a few days for the kits to arrive.I was going to send them out but I shouldnt have any trouble doing them myself.Thanks for the info.