Exactrep Coils

[jayterrence]

I have a question.......
My bike was running exactly like it had a bad coil, Yamaha wanted too much money so I ordered the Exactrep version. Thats where the problem began.... the Exactrep coils are hard wired, you have to put a boot on, also you have to salvage the wiring and solder it on to the new coils!!! This was supposed to be a simple fix that has now turned into a whole new project.
Has anyone done this exchange??? Please don't mention going to COPs, not doing it cause I am already invested! Old coils have cracks in them along the bottom.....And to add insult to injury, I have the pricey Nology wires that match my bikes color, look killer....but noooooooo.....I got to use the ones that are hard wired into the new Exactrep Coils.....Frustrating. Still have to check the spark plugs and make sure one of them didn't crack, but they are new, and once again the high end Eridium plugs to boot. Anyone out there have some advice, I am all ears.
Thanks

 

[Fire-medic]

You should see this:

 

[MaxMidnight]

How did you diagnose that the coil(s) were faulty?
Assuming they were then the simplest solution would be to buy the appropriate Hitachi connector and terminals and fit the appropriate half to the new coils.

 

[jayterrence]

How did you diagnose that the coil(s) were faulty?
Assuming they were then the simplest solution would be to buy the appropriate Hitachi connector and terminals and fit the appropriate half to the new coils.

I video taped the bike during a ride, twice back to back at a red light on a hot day, the bike at idle started to misfire and then stall. It would start right up no problem every time, then repeat. I took it to my tech, and he suggested coils but check plugs and wires, plugs are new and wires are as well so I kind of set those to the side and investigated the coils. The above video I have seen before, and I am now going to back track and have a look at the plugs and wires to see if anything went wrong with their install last spring. I will try and post the video.
View attachment WhatsApp Video 2024-01-21 at 11.52.53 AM.mp4

 

[Radioguylogs]

It does sound as though it was suddenly switched off- it does make it seem more like an ignition problem than a fuel problem.

In addition to suspecting the coils, maybe make sure the kill switch and the kickstand switch are clean? The ignition controller box might also be on the list of suspects?

 

[jayterrence]

It does sound as though it was suddenly switched off- it does make it seem more like an ignition problem than a fuel problem.

In addition to suspecting the coils, maybe make sure the kill switch and the kickstand switch are clean? The ignition controller box might also be on the list of suspects?

The kick stand and its switches are all clean.... this only happens when at running tempurature!! Other than that it runs smooth as silk out on the road, moving, but in stop and go traffic it starts to act up.

 

[MaxMidnight]

Electrical problems are normally caused by a bad connection or a component failing due to heat.
If it was a bad connection then I'd expect the problem to be either intermittent, i.e. not easy to reproduce or when it stops it won't start again.
Same with heat related issues, if this causes a component to fail then it is usual that you need to let things cool down before they will work again.
Whilst it makes sense to ensure that the HT system is in good condition, arking is most likely to cause a misfire rather than the engine to cut out.
Easiest way to check this is to observe in a dark space (NOT enclosed!)

When did the bike last get a full service, i.e. plugs changed and air filter cleaned?
Not a particularly smooth idle, have you balanced the carbs recently?
If the tamper proof plugs are out what are the idle mixture screws set at?
(Helpful hint: Use a good fitting screwdriver and not the one used as a chisel and paint stirrer, and do not force the screws if they are reluctant to turn. Sometimes a sharp tap on the end of the screwdriver will free them or some penetrating oil overnight.)

First rule of diagnosis: Make sure that the basics are right.

 

[Fire-medic]

We probably can rule-out a bad pick-up coil because those will go 'open'/not showing the proper resistance when it gets hot, and the bike can crank but won't start. Heat is usually the issue w/them.

Give the box time to cool down & it will run again usually.

I think an issue w/the ignition box sounds likely. Contact Sean Morley [email protected] for his electrical traveling kit. You swap out your ignition box w/the one in the kit & see if that fixes the issue. If it does, you pay only for that part, and return the kit.

 

[wayne billings]

To Jayterrance I am not the best to diagnose electronics, but after listening to your video, it seems to me that is Fuel and or air. I hope it is an easy one P.S. Check to see if spark plugs are drippy wet when it dies.

 

[MrMAX1985]

I video taped the bike during a ride, twice back to back at a red light on a hot day, the bike at idle started to misfire and then stall. It would start right up no problem every time, then repeat. I took it to my tech, and he suggested coils but check plugs and wires, plugs are new and wires are as well so I kind of set those to the side and investigated the coils. The above video I have seen before, and I am now going to back track and have a look at the plugs and wires to see if anything went wrong with their install last spring. I will try and post the video.
View attachment 92719

I have been chasing this exact problem for the past summer! I had hooked up a oscilloscope to the inputs on the ignition box and could not find an issue with pickup coils when it would happen. I found if I would put the choke inrichener on a little bit when sitting at a stop light the engine would not cut out. Only happens when putting around town (engine warms up to the little dot) and then go to let the clutch out when taking off it will stall if I don't catch it. If I bring rpms up to 1500 before letting out clutch it will not happen. Pulled carbs off this winter and found a couple of small holes in diaphragms where they fold. I am very interested what you find!

 

[jayterrence]

I have been chasing this exact problem for the past summer! I had hooked up a oscilloscope to the inputs on the ignition box and could not find an issue with pickup coils when it would happen. I found if I would put the choke inrichener on a little bit when sitting at a stop light the engine would not cut out. Only happens when putting around town and then go to let the clutch out when taking off it will stall if I don't catch it. If I bring rpms up to 1500 before letting out clutch it will not happen. Pulled carbs off this winter and found a couple of small holes in diaphragms where they fold. I am very interested what you find!

Interesting, a friend of mine suggested a vacuum leak!! I just had the carbs synced and tuned 1 day prior to all of this......MMMMMMMMMMMM!!

 

[CaptainKyle]

Have you checked the voltage out put on this bike ? You could be running in circles because of low voltage.

 

[Fire-medic]

Kyle is correct once again, if the electrical system is not working properly, the ignition isn't either. It needs a full 12V to do its job. Check output going into the battery at various RPM's.

Refer to the shop manual for directions on checking it:

https://dn790009.ca.archive.org/0/i...ice-manual/yamahavmaxvmx12-service-manual.pdf

 

[jayterrence]

Have you checked the voltage out put on this bike ? You could be running in circles because of low voltage.

I have not..... I have checked the plugs, they are good, the wires are new and check out, I am going to do a check on the coils to make sure I am getting at least 3 to 5 oHms on each, the front ones are exposed but still a bitch to get out so ill just check them via the plug. I was going to replace the battery with an AGM, I will look into checking out the charging/voltage output, thanks for the help guys....chasing ghosts sucks.

 

[wayne billings]

jayterrance It does suck but you have a lot of ghost busters here. You will find it. some times it is more than one thing. I find that a brief distraction sometimes helps.

 

[jayterrence]

jayterrance It does suck but you have a lot of ghost busters here. You will find it. some times it is more than one thing. I find that a brief distraction sometimes helps.

I spent the day today going through the whole electrical. Tested plugs, wires, coils!!! Surprisingly nothing seemed out of the ordinary!! Till I got to the battery, low level, old, some corrosion, also found some corrosion on the plug wire, and in the coil itself.. maybe

 

[wilks]

Anymore nowadays if I’m having electrical issues with ANYTHING I’m going battery first.

I’ve had numerous vehicles where issues ended up being battery related.

 

[Fire-medic]

If you get another battery a lithium-ion battery, though it costs more is a good investment.

 

[CaptainKyle]

I spent the day today going through the whole electrical. Tested plugs, wires, coils!!! Surprisingly nothing seemed out of the ordinary!! Till I got to the battery, low level, old, some corrosion, also found some corrosion on the plug wire, and in the coil itself.. maybe

Like said these bikes need good voltage for everything to work right ! (Kiss) keep it simple sam ! Check the easiest stuff first and avoid a lot of work.

 

[MaxMidnight]

First rule of diagnosis: Do it in a logical manner, take measurements and don't guess.