If I read the Mikuni data correctly, the 9EBY01-50 is richer.

 

Also what is the difference between a needle jet and a jet needle

For example, Needle jet: P4, Jet needle: 9EBY01-50

I purchase the needle jet P4 and was surprised to see the tube the needle slides into (well) and not the needle. I changed the needle jet from the stock P8 to the P4.

 

The needle jet is like a cylinder bore for the needle, except in this case you want some clearance obviously. There's a balancing act between the needle and needle jet that affects fuel flow/tuning.

 

Thanks for the help. I'll order the correct needle. While I have your ear, I have a considerable amount of poping when the RPMs are falling and throttle is closed. I'm thinking the new needle would help with this. Idle air adjustment?

 

My header glowed when I first installed. Here's what did (aside from carb setup in my sig):

1) double checked joints were sealed properly on exhaust, including where header attached to cylinder

2) went back in and re adjusted my timing...mine was a touch off, even after I thought I had it correct when it went back together

3) burped and refilled my coolant with moto-ice

4) clipped the jet needle 4th from the top (I'm figuring my setup was a little too lean)

Seems to have made a difference, doesn't appear I have any more glowing and engine runs smoother...gonna keep an eye it when it gets hotter tho...

 

There is also a good tuning manual for the HS40(I think?) that is similar to the 36 and identifies all the needles and what they do...

Can't find the link right now tho

 

Dash:
This one?
http://www.mikuni.com/pdf/hs40_manual.pdf

 

That's the one!

Thank you!

 

Thanks for the link, that will help for the set up. I'm sure after I get the correct needle evert hinges will be good.

How many turns out did you guys set your idle mixture screw? It's tight to get in thee so a base point would help.

 

How did you re-time your bike?