80 XT500, 36mm WhiteBros Mikuni, K&N, Jetson race - Too Rich for my blood.. ;)

[JPinLA]

Does anyone have any experience with this White Bros Carb kit? 36mm Carb..KN Filter.

I've got an XT headerpipe and TT rear pipe with a Jetson Race - Supertrapp Knock off type muffler (from an XR600)...

Installed the carb got it to fire on the 3rd kick (took two to suck in the fuel it seems) but at idle and everything above, it's running way too rich.

It idles but as I click into the needle jet range - it's blubbering and surging - if you hold the throttle open, it's as if you're opening and closing the throttle as it loads up... (I also put in a purolator fuel filter, but I'm going to swap that out with a smaller motorcycle type "disk" filter as this thing has a huge gap of air in it and I'm wondering if that's contributing to the surge...

On the main jet, full open, the sucker sings, it's just that the blubbering beast - (oily gassy plug and black sooty rings on the exhaust) is far too rich below..

I moved the needle clip up to lean it out one notch - but haven't ridden it yet as it was kind of late to terrorize the neighborhood with that beast.. (Still have one left should I need to go leaner)

I thought about going up two notches on the needle, rather than one to save time, but I hope one is enough...

Also - the factory recommends a bp-6es (colder plug) and on the earlier models, it came with a bp-7es, the original owner had a B8ES in there and it ran fine in the stock configuration, prior to carb / exhaust / K&N mods... What do you guys run here?

Thanks in advance!

JP

(Sorry about the dual post, I made a mistake --- figured this would be a better place.. ?

[Wayward Son]

what is the complete current jetting?

[JPinLA]

Eddie, Good morning! Thanks for getting back to me so fast -

The carb comes with one size (I believe) over and under in little bags..

Main jet - I "think" a 230 is in there, as I have a 220 and a 240 for adjustments

Pilot - I have a 3.0 and a 37.5 - so would that mean there's a 3.25 to 3.5 in there?

Needle - I have no clue.. as the spec sheet doesn't state out of the box what's in there.. (runs to net to see if I can search for some info on the factory needle..)

[JPinLA]

I should add, that this kit came from Mark over at Thumperstuff - so perhaps that may give you some insight..

[JPinLA]

One more thing - The bike, when I got it - had the b8es plug in it (I believe this is a "colder" plug than the bp6-es as the thing has run for years on that plug - do you think going back to it would be a bad thing?)

**Update -

Moving the clip up one notch on the needle helped.. but it's still feels "fat".. The surging may be a direct result of that freakin' fuel filter, (*it's practically empty when you look at the clear plastic, so I'm thinking it's too much..) so I picked up a smaller, disk type one that hopefully will work better.

Checked the plug riding up the street at mid throttle - killed the engine - still black, see beginnings of brown, but still looks too black to me...

Picked up a BP7-ES as well - Should I run with this cooler plug?

As soon as it cools down, I'll go up one more notch (so I'll have reached the max on the needle.. ) hopefully that will be okay.. and close enough to toasty brown / light tan..