28mm pwk jetting 4 a ported 4mill

[qboronyrican]

well i double checked with him on the subject and gave him the info ...carb size, temps, elevation ect. and thats what he said both times.....he's a known builder(kevin herr) so i think he knows what he talking about so i went and ordered them.....if they are wrong, what will it cause the bike to do....run rich, lean and @what throttle position...so i know what to look for??/

[JKJK]

You will be looking for new needles. :biggrin: Sorry i had to say that.I believe Kevin is an excellent builder+he made a honest mistake.

[qboronyrican]

if they are wrong, what will it cause the bike to do....run rich, lean and @what throttle position...so i know what to look for??

[JKJK]

I don't know how to explain this any clearer.Using those needles in the 28's,will be like putting telephone poles in place of toothpicks.There will be no room left for fuel to flow threw your main jets assuming they even fit.

[KEVSWS6]

Sorry that is my fault! 28 will take the JJH needle. What needle did those come with. I'm so sorry I got that wrong. Wasn't paying attention. Give me a ring I'll set you up.

[burleybanshee]

I have close to the same engine setup as you do. Had 30oko's on it. Dialed it in with a dyno sniffer and the 158 mains should be right there with a 50 pilot to a 52 pilot. The pilot was in between due to the stock needle, i did not have ones to fit the 28-30 which take a smaller size than its bigger brothers.

 

Yes the bowls run dry, open up the inlet holes on the fuel neddle and it will take care of that problem.

 

I loved those carbs, but they are a little small for your setup and you can make more power with 33 or 35 imo. I did not notice a lose down low when i switched to 35's. All depends on your pipes, reeds and porting, but i didn't loss response and have more top end.

[qboronyrican]

I have close to the same engine setup as you do. Had 30oko's on it. Dialed it in with a dyno sniffer and the 158 mains should be right there with a 50 pilot to a 52 pilot. The pilot was in between due to the stock needle, i did not have ones to fit the 28-30 which take a smaller size than its bigger brothers.

 

Yes the bowls run dry, open up the inlet holes on the fuel neddle and it will take care of that problem.

 

I loved those carbs, but they are a little small for your setup and you can make more power with 33 or 35 imo. I did not notice a lose down low when i switched to 35's. All depends on your pipes, reeds and porting, but i didn't loss response and have more top end.

 

 

if i get jjh needles will the bowls still run dry and if so how do you open up the inlet holes on the fuel needle???

[burleybanshee]

athe correct needle has nothing to do with why the bowls run dry. Take the float off and the needle will come with it. Look at the tube that it slides in. there is a hole in the side that the fuel flows through and into the bowl. Take a drill bite and find the correct size. Then go up two sizes in your drill bit set and open up the holes. I forget the size to open to, use some common sense please. If your drill bit set only has 5 then don't go up two sizes, i'm talking about a 1/16 or so bigger may 3/32 bigger than what it is, not an 1/8 or larger. Should correct the problem.

[qboronyrican]

is this necessary if all i do is ride open trails and some dunes .....is this a drag racing mod, needed for all out wot racing?

[burleybanshee]

It only happened when wot dragging, never letting off and by the time hit 4th, started to run out. Regular duning no, but why not open up the holes and correct the problem so you are not limited, you don't want to starve the engine under load, dragging or trails, engines go boom that way.