In need of serious help!!!

[ImCannibal]

So I got my Max all buttoned up after doing a bunch of work after the accident last year, and it started sputtering then lost power and left me stranded... Sean diagnosed it as the r/r so I did the r1 r/r upgrade plus the crimp delete, now it's doing it again.
I took it out for a test ride and it seems to be losing spark at around 4k+ rpm. I have no idea what could be causing this but it starts popping and shooting flame like it's only intermittently getting spark. My voltage is reading fine at the battery, and I'm not sure what this could be... maybe a bad v boost controller?

 

[Traumahawk]

How long did the bike sit without starting?

 

[ImCannibal]

3-4 months.
I had to replace the stator cover, the front end, the radiator, and a few other things as they showed up.

 

[Traumahawk]

I'm wondering if its time to do a shotgun on the carbs? At eureka springs....I was so lean that I would throw a lean flame with a pop out of the exhaust. It was also intermittent.

A shotgun fix it.

http://vmax.lvlhead.com/tips/shotgun.htm

 

[ImCannibal]

It idles fine, just the higher rpm range where it wants to die altogether.

 

[KDIMD]

Check the plugs. I had a problem at 4k and sometimes hard to start. Turns out I just needed to clean the plugs.

 

[Traumahawk]

Mine sounded fine at idle too....and it basically happened overnight.

 

[ImCannibal]

I'm gonna post a video of what it's sounding like now that I've cleaned out the carbs and it won't start at all. I'll check the plugs tomorrow since it's dark now.

 

[ImCannibal]

https://youtu.be/k1mKvARwkOY

 

[Traumahawk]

After you do a shotgun....etc...I had to give it a LOT of choke to get it started.

Like 3/4 choke.....and it starts with 1/2 in cold weather. so I was surprised at how much it took......but with the choke it will start.

 

[Traumahawk]

This person had the same issue after a shotgun

http://www.vmaxforum.net/showthread.php?t=35727

 

[ImCannibal]

That video is with the choke fully open on my bike.

 

[Traumahawk]

Whats the volts on the battery? When mine would drop to 10 volts....the engine would turn over fast....but wouldnt start. I learned that the hard way one night.

 

[ImCannibal]

Voltage was fine before I did the shotgun, I killed the battery trying to start it. Once it drops below 11v I give up and recharge the battery. I'm going to check the cold/hot resistance on the pickup coil tomorrow, see if it has anything to do with the stator that was attached to the cover I used to replace the old one. I'm also going to check the plugs, and re apply contact grease to all the COPS boots and connectors just to make sure.

 

[ImCannibal]

An odd thing happened when I tried to start it with the air box off, that was very revealing. Those loud pops you hear coming from the motor are actually a pressurized discharge from the carbs, shooting up and out... doesn't seem healthy at all.

 

[Redbone]

Are your plug wire routed properly? Mine did something akin to this when I had the front two wires crossed doing the COPs upgrade.

 

[95spfldmax]

Will it fire up if you prime it first? If it does, fuel starvation. If it doesn't, most likely ignition related?

 

[customizedcreationz]

You have to narrow down whether its fuel or spark.

If you just did something with the ignition, I would say that is probably where the problem is. And vice versa, if you just did the carbs, well look there. If you did the two together... well make a check list and go through it.

Its obvious your getting spark and fuel, just possibly not good enough to start. I would check the plugs and wires to make sure you have them on correctly as Redbone stated. I know its stupid, but we all have done it.... and sat there and scratched our heads thinging something major has happened. I bought a 78 Z28 350 4spd off a kid.... he rebuilt the motor and put the wires on wrong. I took a chance and brought it home check the wires and bingo, three of them out of place.... swapped them and vrooom!!!! Made a healthy profit off that car.

Retrace your steps on the cops. Fuel related is more time consuming to pull apart I would say, but its very easy when you find the problem. Doing the shotgun again might be a good quick way of checking what's happening and eliminating that quickly.

I hate when problems arise after the bike was running fine, but I enjoy the Doh..... it was this.... I blew a main fuse twice for some reason I dont remember and scratched my head on it till I found out it was the fuse. And then found out it was a hot wire that broke and arced.

Good luck.

 

[Irtron]

Are your plug wire routed properly? Mine did something akin to this when I had the front two wires crossed doing the COPs upgrade.

+1.
in the video it sounds like the timing is out of line.

 

[customizedcreationz]

Usually popping through the carbs is timing and backfiring through the exhaust is carb related.