Viper "flat" feeling after rebuild


Always always always only do/change one thing at a time. But yes, I always leave the PTO richer. Cheap piece of mind. I don't care that it is running rich.
 
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Check the pulse line from the pump to the engine looking for gas. I just had a SRX700 and a Phazer suck gas through the fuel diaphragm and into the engine within a week of each other.
 
I checked the pulse tube, and was dry. I ended up with 147.5-150-150 with 45 pilots. Air screws 2 turns out, and needles at 3.25. I rode 100 miles today and ran really good. The DCS light did come on at times... not sure why. PLugs looks good to me. The piston wash doesnt make sense though. It has been 230 miles since the rebuild and the wash is still barely there. Ideas?20190307171209.jpg20190307_171409.jpg20190307171236.jpg20190307171304.jpg
 
For cracks? When I did the rebuild the pipes got wire brushed and painted. Everything looked good. I will double check though
 
For there to be no wash like that the PTO has to be rich right? The other 2 seem rich as well based on the wash?
 
Yea any ideas are welcome. It is odd that the plug looks ok. They read a little rich, but not wet looking. I would think that if that cylinder was so rich it wasnt making any carbon that the plug would be black and wet.
 
why would you unhook the vents from the airbox? you get better more consitant performance of the vents hooked to the airbox. put the vent hoses back where they were stock, then use the appropriate jetting, 47.5 pilots and likely 160-162.5 main jets and see how it runs with proper jetting. I don't ever take fuel away from a engine with mods like triple pipes, etc. and expect it to run good...…...
 
I just picked up 160's and 162.5's to try that. I guess i didnt know there was a difference as long as it was jetted correctly. Aaen recommended not hooking to the box, which is why they were like that. I will give that a try. Not sure if i will be able to anymore this year :( It ran great when i rode last week in about 20 degrees. Just odd that there is still not wash like i expected.
 
So did you leave the Opticool headgasket in? That was a Bender Racing fix but their pipes ran at 8500 rpm's where the highest spike was with the CDI box. I think the Aaen's run at 9000 rpm's if I remember correctly...? One thing I do remember with some of his pipes is he seemed to build some forgiveness in them and they tended to run rich.

I ran the Simon's CPR pipes one season on mine and they also were 9000 rpm pipes. As Mr Viper would point out most did something with the heads on these being the staggered compression they came with stock wasn't the most optimum for piped ones. I ran an aftermarket Speedwerx one piece head on mine with removable domes so I could set the compression even across the board. Others ran the Mega Power one piece heads and some just had their stock head re-milled.
 
Yes the opticool is still in it, and i am running 8900-9100 rpm. The places that cut the stock heads around me, are not doing it anymore. I have been keeping an eye out for an aftermarket head, but haven't seen anything worth buying. It looks like you can still send the head to Bender to get it milled, but is 175 bucks, and after dealing with them on the opticool i dont know if i would send them my head. I will keep an eye out for a milled, or aftermarket head. Or if anyone has one let me know! thanks.
 
and resize the chambers? it isnt something special they need to know? just make all the cylinders the same as the center and mag is stock?
 
Darn I had a spare head I threw out a few years ago. I asked on here if anyone wanted it. It was from a blown up Viper but I figured it could be machined out for a deal like this.
 
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