Bike dying.

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KDIMD

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For a while, my bike would just die while riding. Would pull over to side of road, wait a minute and would start up again and go on without any problems. Then the last two outings, it got worse and would die after going a few kms. I adjusted the carbs, floats, needles and jets based on recommendations from a supercharge expert (I run the Holley 390 carb).

Then last night it did it again, and right after I engaged into gear. I then figured it must be my side stand switch so I cut the two wires below the connector and twisted them together and rode home, although it was having a lot of fits. I assumed it may be because the battery was low from constant starting and stopping.

1) Would a bad side stand switch kill the bike at random times (after engaging into gear and riding for a while)? Can I ride without changing out the sidestand switch, just leave the wires connected?

2) Will a low battery cause problems with the Dynatek 3000 module running properly?
 
Yes, #1 is possible but not likely.

#2 is also yes, as electronic ignition systems like a full 12 V to work properly. You might check your ignition pick up as they can go 'open circuit' (no conductivity) when warm. I've had 2 go bad like that in 25 years. Search on here for the ohms reading you should be getting w/the engine off.

You have the 1990+ ignition, a single pick-up sensor, & easier to source compared to the 1985-1989 two pick-up coil (sensor) system.
 
I had a KTM 450 SXF that had hot start issues. The pick up coil "ohmed" OK but I'd have to jump start it off a car if it stalled when hot.
I changed the PU and it worked fine after that.
Still finicky but started.
 
I have the COPs installed. Would that impact this?
 
No, the pick-up coil is what senses the position of the crank and tells the ignition, 'time to spark.' The electronic ignition then tells the appropriate coil, whether on-top of the plug, or the stock locations, to fire a specific plug.

When the p-u coil goes bad, it will become non-functional after warming-up, in my experience. Let the bike cool, and it works. But, intermittently.
I have the COPs installed. Would that impact this?
 
When you say 'dying' do you mean a sudden switch like cut which would suggest electrical of a drop of revs or power which would suggest fuel.

Forgive me if I am wrong but it seems that you are guessing at the cause.

Base you actions on facts i.e. you suspected the side-stand switch so first measure the voltage going to the switch, try wiggling wires and see if it changes. Next check the continuity of the switch if OK and the stand retracts correctly then don't waste time cutting wires which will need to be repaired later.
You suspect low battery voltage.
To cause the engine to die then the voltage would have to be low at the time it stopped and not after several attempts to start the bike.
If the starter turns the motor then it is unlikely to be battery or charging system but check this by measuring battery voltage (NB Not just after you have run the bike as this will give a false reading)

Guessing just wastes time and causes frustration.

Start by accurately describing the issue then work through in a logical manner and base actions on measurements wherever possible.

You may not find the culprit first time but you will know what it isn't.

Lecture ends........
 
Here's my 2cents.. hope it helps you to iron out this issue.
When my PU coil was showing its age, I could start the bike from a cold temp engine and it would fire up fine.
When the temp gauge started to rise about 1/2 the way till the red zone, I noticed that the bike would not sound as smooth as it did when 1st started.
When the temp gauge got close to 3/4 to the red zone, the bike would stutter badly, then eventually die completely. Of course I could not trust riding it during this time.
Note: this condition got worse as time went on, while gathering information as to what could be the problem.
Once I found the PU Coil connector, tested resistance when it was cold (it read close to specs), but, once the bike warmed up and died, I tested it again, and it read like an open circuit.
I picked up a replacement PU unit from regulatorrectifier.com. It's been fine ever since.

Good luck finding the issue.
 
Mine was doing something similar. A few months ago, I rode 2 hours to Dallas, then on the return home, it died about 5 times... in the dark... in the middle of nowhere in Texas. Not cool. But after letting it sit a while, it would start again and run fine for a few more minutes.
If you decide to go the "fuel" route, I would recommend 2 things:

1. Replace all rubber fuel lines and filter. The sharply bent hose going into the filter is known to develop holes and cuts that can allow the pump to suck air instead of fuel. I replaced mine with OEM to avoid kinking a standard hose.

2. Replace the fuel pump with new OEM. My old pump was failing - loud clicking sounds constantly with initial key on and during idle. I removed, disassembled, and inspected the pump, and it looked fine. But I purchased a new OEM pump anyway for about $200 from Ebay... just for my peace of mind.

After accomplishing those 2 things, my bike starts and runs perfectly every time. No more constant "clicking." Now when I turn my key on, there is only 1 or 2 clicks and it's primed. My V-Max is very dependable now, and my faith in it has increased substantially.
 
Thanks for all the suggestions.

A few months ago, the bike would just die at speed, about 150 kph. Like the engine was turned off. I coasted to the side of road and after a minute, it would start up and would die again at around 150 kph. Then a month ago, after riding a bit but not hitting prob 80 kph, it would do the same, just turn off. Again, would start right up. Then last week, just died as soon as I put it into gear. I figure this was a side stand issue as would idle fine until I put into 1st gear. I cut and twisted the wires together, and it was able to go into 1st gear but rode very rough with carb sputtering alot. Only reason I questioned the voltage is that I hadnt had time to charge the battery after all the stalls. I just put on my trickle charger and it was at 12 volts, so bit low.

I have replaced all new fuel lines (yes had a pinhole in the u shaped hose) and new filter. New fuel pump. I run a Supercharger and Holley carb so the vboost and yammy carbs would not be relevant.

Anyway, having my indie mechanic come by tomorrow and will check out the p/u coil and some other items. He is also replacing my front end with a Morley USD fork kit so hope to get the fuel issues resolved.
 

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