SkullDuggery's Carb Jetting, Opinions Welcome..

[SpecOps13]

Finally getting somewhere. Few more fixes and this bike will be GTG...


Below's a picture of where my current settings are running as far as an average, plug reading. I currently have 147.5 mains, stock needles shimmed 0.034. Air / Fuel 3 turns out.. Everything else in the carbs is stock. K&N Air Filter, stock air box. Exhaust is a Kerker 4-1 with 2-1/4" core of my design.

IMO this is about as lean as I'd ever run a bike. Just wondering if it may be a good thing to pop the 150 mains in??? What do you guys think??

 

[KJShover]

Finally getting somewhere. Few more fixes and this bike will be GTG...


Below's a picture of where my current settings are running as far as an average, plug reading. I currently have 147.5 mains, stock needles shimmed 0.034. Air / Fuel 3 turns out.. Everything else in the carbs is stock. K&N Air Filter, stock air box. Exhaust is a Kerker 4-1 with 2-1/4" core of my design.

IMO this is about as lean as I'd ever run a bike. Just wondering if it may be a good thing to pop the 150 mains in??? What do you guys think??

It couldn't hurt. At one point I was running :

Kerker w/carbon can and 2" comp baffle
Stock box w/ K&N
a/f 3 out
Needles shimmed .020
150 mains
440' elevation

It ran just fine with great mpg. But noticeable difference when I made the jump to Morley's jet kit. Still get great milage, c'ept now a more beefy midrange.

 

[SpecOps13]

Added: I uploaded the picture that should have been in the 1st post all along. Wife was rushing me for Supper and I forgot it to start with...

Thanks KJ. Bike runs well, I'm running Non Ethanol. Going to 150's would darken the plugs up some and allow for use of Ethanol in case I get out too far. I think it'd be lean on Ethanol right now, here at Zero Altitude.

 

[[email protected]]

If its running good id say leave it. 147s are pretty normal with aftermarket exhaust. The porcelain being white may not be a big deal depending on you school of thought regarding plug reading. Some say porcelain color some say base of threads. Either way, if you aren't surging from being too lean, run it. I've heard Sean say more than once these bikes like it lean.

JMO

 

[SpecOps13]

Mike, It's good to hear different thoughts. The bike runs good right now. My thoughts were that it was a little too lean. I'm really up in the air about doing the 150's...

 

[Blurr]

I don't know how helpful it is but my completely stock bike plugs I pulled out this morning look just like the one third from the left. Did you use a flash to take the picture?

 

[SpecOps13]

Flash, Yes. Have to in my garage or the picture wouldn't turn out... That 3rd plug is the right rear plug...

Thanx for the input. Yamaha has factory settings Lean for Emissions and EPA... Atleast I know it's safe as lean as it is...

 

[KJShover]

To me, they don't look lean as far as jetting goes. They look pretty good.
A little a/f tweaking would put a little more tan in them puppies.

 

[SpecOps13]

Amazing how fast pictures can explain something to perfection...:biglaugh:

Thanx for taking the time KJ. Guess I was thinking these VMax's needed the plugs to run darker.
The plugs on my 94 are a Light Golden Honey Color and the Air / Fuel is almost a flat 14:1 all the
way. Sean said it would make more HP if it were richer... Good idea to fatten the A/F Screws out
a little farther and/as they are running fairly even, to maybe 3-1/2 turns???:ummm: I'll do that, check and see.

Thanx,
Dave

 

[CaptainKyle]

Leave that poor bike alone & ride it:biglaugh:

 

[SpecOps13]

I went ahead and turned the Air / Fuel Screws out another 1/2 turn. The plugs are just a tiny bit darker so, I'll do what Kyle suggested,,,, Ride.... :rofl_200:

Still got a damn shift shaft leak.....