Carb is a year old . Had it sonic cleaned . Runs great , but can't get the mixture right at idle . No matter what jet I put in I always end up with one turn out . I've used from a 25 down to 17.5 and all sizes between . I have also used 97 and 98 needles with the same results . There is no leaks at the manifold at all three gaskets . Any ideas ? Or do you think the is carb bad ? BTW 98 FLSTS
Check your float setting.
thanks . I'll give it a try tonight .
Float setting is .710 which is pretty much dead on . Any other suggestions .
Quote from: Ironheadmike on July 22, 2019, 07:47:04 AM
Carb is a year old . Had it sonic cleaned . Runs great , but can't get the mixture right at idle . No matter what jet I put in I always end up with one turn out . I've used from a 25 down to 17.5 and all sizes between . I have also used 97 and 98 needles with the same results . There is no leaks at the manifold at all three gaskets . Any ideas ? Or do you think the is carb bad ? BTW 98 FLSTS
My 2000 Heritage with Mik42 has 22.5 and 97 needle center clip and is running really nice, a little on the rich side but awesome road manners.
Bike is 95" and Andrews 26's
Stock exhaust system with drilled out mufflers.
I wanted to play with it for a little better gas mileage (38) but afraid to touch it!
JHMO
:missed:
Right now I'm running the same setup .
Quote from: Ironheadmike on July 25, 2019, 03:47:15 AM
Right now I'm running the same setup .
Everything else being equal, I would guess a bad passage in the carb, either blocked or bad from the beginning.
I've had carbs over the years that I could never get right. I keep them for parts
:nix:
You're turning an air screw so as the engine gets hotter it Should idle better with more air, are you fully warmed up? If warmed up then I'd suspect the engine is getting the air mixture from somewhere else like a leaky intake seal.
It is strange that the symptom is constant with different slow jets, that would point to the fuel passage between the jet and bore.
Do you have a legit Mikuni? is it stamped with the bore size ie; "42 or 45" on the side. There's a lot of cheap copies out there now.
it's a Genuine Mikuni . I bought it from a local dealer who I have been doing business with for over twenty years .
i look forward to the solution
I usually start at this point on a 88 or 80
22.5 pilot, 1 turn out - usually end up with a 20 in a Evo though from memory as it has been a while
-98 needle, clip 2nd notch from top
165 main
#50 acc pump
How different is yours from these?
Check Your Choke plunger, The Rubber seal on the end of it, Not Sealing or missing.
I'm running a 20 jet , 50 nozzle , and a 98 needle and 1 turn out . The bike runs fine . A little flat on acceleration . getting about 32-33 mpg . And no matter what jet , 17.5 -25 it runs at about 1 turn out . I ordered another carb and now I'm debating on finding a new manifold , But again there are no leaks .
Check the choke plunger at the end of the choke cable. I've had HSR's come in from customers that assumed the stock plunger was the same as the Mik HSR. Stock plunger pin measures .328" The Mik plunger pin is longer. :wink:
John
It has the Mikuni plunger
You know that the idle mix screw works backwards on that carb?
It is an adjustable air bleed not a fuel needle.
Turn it out until it misfires then turn it in until it smooths out and RPM peaks, this will give you a lean best mixture.
Do this on a fully warmed up motor (50 miles)
I just went out and checked mine, it is at 2 turns. I have no idea what is inside the carb, I have not touched it in ten years.