Thanks. I'll post back with results

 

ahh.. So the Hi flow AP's are discontinued. Since that screw is not the AP adjustment, you recommend a carb clean/rebuild, or just roll with SS?

 

As Farm Shop noted, the accelerator pump is not adjustable.. So I looked up Keihin parts diagram to see what he was stating and it does appear that it's a fixed connection.. Unless some one can post a pic stating otherwise, I was wrong in my other statement.

 

There is more than 3 models of Keihin Carb.. I will dig one up...But... the one with the Plastic "cam" on the other side... you can see exactly how it works...
the early one was direct to the Butterfly "cam"..ie not adjustable.. Like I said... the Least expensive Carburetor available at the Time!!!

No I lied... it is still on the side shown... threw me because there is not a screw in the one shown..
the screw should be at about one oclock, just outside the blue circle.. either removed on purpose, or "adjusted for full stroke" and the Screw fell all the way out..


Gotta have Hi volume Pump????? even tho 98 HRFB is not using one on the HSR at all!!
98HRFB's Bike is Obviously "Tuned"

 

[QUOTE=Racepres;18682003]There is more than 3 models of Keihin Carb.. I will dig one up...But... the one with the Plastic "cam" on the other side... you can see exactly how it works...
the early one was direct to the Butterfly "cam"..ie not adjustable.. Like I said... the Least expensive Carburetor available at the Time!!!

No I lied... it is still on the side shown... threw me because there is not a screw in the one shown..
the screw should be at about one oclock, just outside the blue circle.. either removed on purpose, or "adjusted for full stroke" and the Screw fell all the way out..




Gotta have Hi volume Pump????? even tho 98 HRFB is not using one on the HSR at all!!
98HRFB's Bike is Obviously "Tuned"[/QUOTE]


Yes it's is Racepres and I know you know Johnjz, it's his loaner stroker motor and I must say it's very smooth and powerful.... Great guy.. Next year my 96"er should be completed and back in frame.. can't wait..

 

I switched to an s&s and will never look back but it all depends on what you are looking for. I've had good luck getting a keihn butterfly tuned in on sportsters and big twins running stock air box and exhaust.

but once you change air cleaner or exhaust I really haven't had a lot of success. But not saying it cant be done. In my experience once you get enough fuel in the idle circuit so it doenst pop on decel the off idle and midrange ends up way rich.

 

I find pop on decel is usually exhaust related... if the damn EPA cap/Plug has been removed from the idle mixture screw..

and 98HRFB; the keihin is equipped with a screw for limiting the Acc pump stroke... If it has that big ole Plastic "cam" on it... the one pictured is Missing... resulting in full acc pump stroke!!

 

As long as you have that carb, you will have a hesitation. They never really ran very good.
Replace it with an S&S E or even a later model Keihin CV carb, you’ll thank yourself.

 

On a Stock Motor!!! I call BS and too distracted to learn to Tune the Thing... A/F is A/F... the Carb Nor the Bike know how you got there... hell an S&S Super "B" is Nothing but a Bigger Linkert!!! while an "E" is more like a Big Bendix.... Not a long Stretch to a Ka-Sneeze ... either
While we are here in the EVO section... I will say that the Manifold that the Butterfly Carb was on, is problematic... If one really wishes to "Modernize" an early Evo, the newer intake Manifold, with a Modern carb....ie CV, and now you have made a real Difference!!!!!! You are certainly correct on that account!!
May surprise folks how many of those early manifolds develop problems, then an aftermarket Carb is installed...and the Problem magically disappears... Stop and think.... Did that Magic carb come with a Different Manifold??? At least new seals??

 

Thanks Everyone. I'm going to rebuilt carb, clean and replace all gaskets. It ran fantastic until Accelerator Pump diagram gave out. Maybe I didn't replace it right. lol Either way I'm going to give it a go. If I can not fix it, I will purchase new SS Carb. I owe it to the bike, myself and you all to give it a shot. Thanks for the help. I'll post back sometime this winter when I get all the fixens done and share how Carb turned out.