A quick question on the Edelbrock carb jetting. When running WOT for 10-20 seconds, through all gears, at the top of 5th gear it stops pulling and starts cutting out. I know it is not the rev-limiter. It only does it after 10-20 seconds of WOT riding. All other times it runs great. The plug checks out as a tan/brown color on the insulator material, with a dark/black color on the base ring. There are some small yellow deposits on the ground strap. I am running TORCO 110 leaded gas.

My question is, is this cutting out because I am rich or lean? WOT in 1st, 2nd, 3rd gear runs great. Is the bowl running dry and causing a lean condition, or is the engine heating up after the long run and causing a rich condition?

Thanks for any help or tips you can give!

RR1

 

If you are not lean popping on decell, you may be too rich..It is hard to get a good plug reading with SOME high octane.On a mikuni carb without accelorator pump i have had a top end bog due to running too rich [felt it more when hitting the whoops]..if you have stock compression i would not recomend running 110 octane, it may not be burning right if motor calls for lower octane..it might be burning too fast or too slow, but i may not be 100% right in this case .J.M.O.check temp frequently if possible and try to jet a bit more lean to see if it stops your problem..or try lower octane..Good luck

 

If you have the stock 9.2 or 9.4 CR, whatever it is, 110 will most likely slow you down and cause your motor to run poorer than it should. You only need that octane if your motor needs it. If you know this info already then I apologize. Not everyone does.

 

You've modded your motor with higher flowing carb,exhaust, new cdi, so you are probably getting more rpm than you did before. A stock Warrior will float the valves at extended rpm runs,it is possible you will need aftermarket valve springs to handle the freer flowing,higher revving motor you now have. That way the springs won't oscillate at high rpms and cause the miss and loss of power at the top end with extended high rpm speed runs.

 

Call Rob or whatever his name is at Barnum's Pro is my only suggestion. He should have the most experience.

Do let us know what happens though!

 

too hi of octane...

 

Thanks for the info guys. As far as the gas goes, for normal trail riding I usually use 92-94 octane pump gas, but whenever I race I use real racing fuel. It is more consistent and pure than the crap out of the pump at the gas station. Also, the lead in it acts somewhat as a lubricant for the cylinder and valves. In the future I will be running VP Ultimate4 race fuel. It is a 92 octane, leaded, oxygenated gas. I doubt that my problem is the gas, but I will try some pump gas to see if it happens to fix the problem.

It doesn't seem like the valves could be floating, either. Nobody has ever told me that I need to run stiffer springs with a Stage 1 cam. I think if it was a problem, then someone I talked to would have brought it up. I am not getting "More RPMS than before". I could easily hit the rev limiter (9000rpm) in 1st-4th before. I can still hit it in 1st-4th, and the valves don't float then. I only have the problem after 10-15 seconds of high speed, high rpm operation. The way I understand it, when the valves float, it happens above a specific RPM, irregardless of how long you've been at that RPM. I may be wrong, but that's how I thought it worked.

I kind of thought it may be a little too rich up top, so I will try using the next needle size lower. Have any Edelbrock users had to go above the 21E needle?

Thanks again for the help.

RR1

 

I thought when you actually dyno tuned your Raptor, they went back to the 19 needle. I would definitely give that a shot again.

 

Check your float level and see if they are where they should be. If they're too low then you could be running out of fuel as you suggested. Just for the heck of it... check your fuel line for restrictions...... you never know!

 

RAPTORRACER1- I know you probably dont want to hear this again but with stock compression or anything lower than 11:1 you will definitely lose performance if you run 110 octane fuel.i know from experience because i went through the same symptoms as you are having at high rpms and the problem went away when i went back to 92 pump gas.the higher octane fuel will act very similar to running too rich if your motor doesnt need it so i would at least try the 92 and see how it works.let us know if running the 92 pump gas solves your problem because i for one am pretty confident that it will.