Between work, bad weather and a cold I finally got my wego 3 installed and ready to get my bike tuned. Its not staying on permanently, just until its tuned.

 

Let the fun begin!

Record some of those runs and I'll see if I can help you. What carb are you running?

 

I got a Hillside stage 2, w8, mikuni hsr 42, d&d fatcat

 

Should be a runner, be aware of changing idle AFR with the air screw affects the AFR's on the low jet in low rpm range with the Mikuni unlike a CV. Said WTF a couple of times until I figured out that i tweaked the screw with no jet change and AFR's was changing in the low rpms.

 

right now it has a 25 pilot, 165 main and the needle clip is in the center position. I had a small indy shop dyno tune it so I'm not sure how many turns they set the air screw at. I think theres more to be had out of it.

 

Heres my dyno sheet

 

Can see the first run was lean and some loss, final run is getting into 14.0-14.1 which is still lean. Run your Wego into the upper rpm's to make sure the real world riding reading is the same, the O2 sensor closer to the exhaust port may read more accurate than up the pooper unless the dyno operator used the same O2 bung.

Graph drop in the early rpm's is the accelerator pump hitting and then cleans up, not a bad thing to control detonation at throttle roll on. Running down the road in cruise the needle controls the AFR, found 13.8 to be the best cruise AFR with 14.2 gets some more mpg, I'll take a slight amount of mpg loss for peace of mind on a 98 degree day and that is the 13.8.

If the graph is accurate compared to the Wego a good chance of needing to richen the big jet by 1 for the WOT higher rpm's will get a little more out of it. With the accelerator pump hitting and known good high rpm's AFR at 13.2 range, bump the timing up and ride it again, timing pulled back is loss of power, with safe AFR's you can bump it until a slight rattle is heard on throttle roll on and pull the timing back, full power is just on the edge of detonation. Advancing the timing can lean AFR's .1 per 1 degree of advance so that is why you need to run it after any timing adjustment.

The Wego is a great tool but don't overthink it, a carb isn't a precise measuring devise, it is a controlled drip.

LowriderHarold and Mr3horsepower ran the Wego and can add some real world riding tuning advice on a warmed up Evo.

Something else is the 2-1 is doing it's job, no torque dip at 3000, just a slight fall off from the accelerator pump slightly rich, wouldn't mess with that

 

nice....wish I had a wide band with data logging...I'm stuck relying on reading plugs.

 

Buy one tighta$$ or sell a kidney, you have to stop and take more **** breaks but it still gives you enough time to tune a engine.

 

Know nothing about a Mikuni, so I'll sit on the sidelines for support.
Helped a few buddies with CV's & S&S, but no slide carb. I'll watch & learn.


Ride Safe,
Harold