2-3k stumble at wot. Need help

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wonderimg if that's from the type fuel in your area....is it algee growing or looks like crap gas?
 
Looks like buildup from bad gas to me....like it evaporated...and that was the residue left over..
 
Well, I got bored and decided to check my plug wires tonight. The right rear one has clearly been arcing. It's cracked and dry rotted like crazy. Whenever the cops arrive, I guess I'll get to start over on tuning the damn thing. Makes me mad, because the bike was running flawlessly before I installed the jet kit. I guess I prolly disturbed it in the process of pulling the carbs. It sure picked a hell of a time to start acting up, but now at least I'm pretty sure I've got it whooped. Never felt a misfire except at wot 2-3k rpm. I guess it's just time, and I'll have peace of mind with the new setup.
 
Well cops on and working. Absolutely no difference except cruise speeds leaned out. I decided to try a 165 in the paj2 spot, and it helped with that. Still had the wot 2-3k problem, so I put the needle at 1.5 clip. Helped a little. I then changed the main down to a 155, and now its hit 10.5 to 1 wot 2-3k. The cruise is now in the 18-1 range, and the smaller paj2 is still in there, and mixture screws are 4.5 turns out. I'm guessing the pilot fuel jets are partially clogged causing my issues with cruise, but I still can't explain why the rich problem still exists wot 2-3k. Seems like a clogged pilot fuel jet would make it too lean in that range if anything. The only thing I haven't tried is swapping back to stock needles, and I don't really see how that could help it.
 
Carbs completely disassembled and cleaned. Found nothing wrong. Put back together, still the same. I swapped down to a 160 paj2, and it still took about 4.5 turns on the mixture screws. I'm a hair leaner than 17 on the floats from experimenting on the rich problem. I tried putting stock and stage 7 springs in, and not much difference, so needles not pulling early. Could the CDI box be causing this? Some electrical problem?
 
So, I've got a dyna 3000 on the way. I've also bypassed the rectifier harness plugs, and am going to run it straight to the battery. That should eliminate pretty much all electrical possibilities. Past that, valve adjustment? I've read that the valves on this thing usually tighten up when they get out of adjustment. I would assume that would cause more vacuum and pull the needles early? Still just brain storming.
 
Front left head pipe right before the bend that goes under the bike.

I would relocate it further back so it reads more than one cylinder. If I had a 4-1 I would make it read all four.

You can drive yourself crazy with too much data as well. At some point getting an overall average reading and trusting that you've set all carbs up the same is enough.

Also, I don't know about your WB but in mine there is a "smoothing" function that softens the response so it doesn't drive you nuts.

I don't really pay much attention to my WB at all under 3000rpm.
 
I wouldn't worry Much under 3k if it wasn't so drastic. 10-1 is just too damn much, and it bogs down pretty bad. Then when it does make it to 3k, it smokes the tire. Given, my tire is about ready to be replaced, but if it did grip, I believe the front wheel would lift. It's almost like revving and dumping the clutch when it hits 3k.
 
Well, I put 162.5 mains in, and swapped back to stock needles (looks to be right around 13-1 7k and up). The trouble spot is now only dipping to 11-1 or so. I did put a shim on the needles, so I'll prolly need to take that out, and maybe play with the springs a bit. It's way better right now, and somehow, the stock needles took care of the pilot circuit being lean. I was needing around 5 turns on the screws to make it cruise at a decent afr, and now I'm about 3 turns out. The stage 7 needles are apparently too aggressive in my case. I'll update if I ever get it all dialed in.
 
Well, I put 162.5 mains in, and swapped back to stock needles (looks to be right around 13-1 7k and up). The trouble spot is now only dipping to 11-1 or so. I did put a shim on the needles, so I'll prolly need to take that out, and maybe play with the springs a bit. It's way better right now, and somehow, the stock needles took care of the pilot circuit being lean. I was needing around 5 turns on the screws to make it cruise at a decent afr, and now I'm about 3 turns out. The stage 7 needles are apparently too aggressive in my case. I'll update if I ever get it all dialed in.

Great post, seeing positive progress with some documentatikon of where you were, what was done to get where you are now, and the results of the changes...This kind of stuff really helps all of us...

Thanks
 
Well, I've now tried factory pro needles, and its even worse with those. I also swapped the paj2's back to stock. I have new emulsion tubes (mine look great to me, but maybe i just cant see it) and o-rings, and jet block gaskets on the way. I have the stage one needles in right now, but haven't tested em yet. I'm feeling good about them though since they're so close to the sock ones, and they can be fully adjusted. If all this fails to work, I'll be waiting til winter and adjusting the valves (gonna be doing it anyhow). I'll update tomorrow when I test drive it and realize it's perfect. ;)
 
Oh ya cool cool. Sure is great acing a dude like Sean around to help.

So the stg 1 are running better for you now...coool
 
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