stock jetting for aftermarket exhaust??

benztech · Full Member Joined: Sep 01, 2009 Posts: 62

My 75' came with a kerker 2-1 exhaust. I'm not running the megaphone as it fell off on the highway about a month ago. Sad

So basically I have just pipes and nothing else. (I run the stock airboxes with new filters from mikesxs)

I got the PAMCO, new advance springs, timing is set and valves are in spec.

here is my issue. I get a 2500rpm dead spot. bike will sputter till about 3k and then she'll pull out of it. the bike will start first kick, idle all day, but I get that dang dead spot and I feel a lack of power going WOT. I also getting backfires going WOT and letting off the throttle. following the carb guide, everything is stock in the carbs and set to factory. I bought an NOS carb rebuld kit and it came with a float guage and I set the floats correctly.

i'm assuming I need more fuel, but when I pull the plugs they look rich. any info would be great.

FYI, I have lambda gauge and i'm tempted to rig that sucker to my bike.

schtipp

try moving the c-clip one slot leaner on the needles

yamaman

Was it running well before your exhaust dissapeared?

Some set ups are just untuneable, fix you exhaust first!

woodman · Full Member Joined: Oct 12, 2008 Posts: 256

leaner ?

gordo

woodman, try bringing the needle up a notch. The stock pilot jet work's through the whole rpm range, but on the transfer stage(about 2000-2500rpm) is when the diaphragm's start to lift. And above like5000, your running on all three, pilot,slides full open, main jet. I would try one notch richer first. If it gets better, go one more. And vise- versa. But as yamaman stated, you should get a muffler,for your own ear's sake.

woodman · Full Member Joined: Oct 12, 2008 Posts: 256

Schtipp said to make it leaner, raising the needle is richer {lowering the clip}, raising the clip, is leaner {lowering the needle}, I agree with you

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