Carb Help

[rocky2by]

Need a little help with my carb setup. I did send the carb and head off to RB Designs, and that made a huge difference, great low end, great top end, and it also smoothed out the whole power band. But the transition from early- mid to top is still not to great, it's kind of dull, or boggy then a hard blast through to the top, then the top end is soooo... smooth and pulls very strong once you get to it. He set the carb up with a Pilot jet #42 a Needle clip postion #CEK-3 and a Main jet 178. Any help with the the Mid range would be great.
Thanks, Steve.

[coopernicus]

Altitude and temps would be helpful, type of carb (AS1 or AS2), as well as motor size and year. I found the RB-D recommended pilot, needle, and main absolutely did not work at 5280 ft (about 1700m) and higher.

Eric

[Jakobi]

And what have you tried thus far?

If the PV opens too soon, or too late it can cause a dip in the midrange power.

Jetting wise, the 1/4 to 1/2 throttle range is the clip position. Does it still pull well, just slowly? or does it kind of fall flat in the midde? Try going a clip position richer and seeing how that effects the power.. If its worse, go back the other direction.

As above, if you want recommendations re various OEM needles and setups you'll need to provide more details re the bike, alt, fuels etc.

[rocky2by]

Thanks for posting guys, My bike information is 2013 EC300 I have not adjusted anything since I received it back from RB, I am running Klotz 2T oil at 50/1. In the mid-range the bike still pulls, just VERY slow and flat feeling, I have not messed with the air fuel screw either, as I thought it is more of a jetting issue. I really like this bike a lot and hope to get it running correct.
The stock setup was N1EK, Pilot jet42, and the main was a 175, I will also check what the plug is looking like.
Thanks, Steve.

Originally Posted by Jakobi

And what have you tried thus far?

If the PV opens too soon, or too late it can cause a dip in the midrange power.

Jetting wise, the 1/4 to 1/2 throttle range is the clip position. Does it still pull well, just slowly? or does it kind of fall flat in the midde? Try going a clip position richer and seeing how that effects the power.. If its worse, go back the other direction.

As above, if you want recommendations re various OEM needles and setups you'll need to provide more details re the bike, alt, fuels etc.

[Jakobi]

Are you sure it was an N1EK and not N1EF? If so the factory has made a change. The problem with that particular needle is that the straight section is so short you are really only on it for a moment.

I'd recommend either and NEDJ/NECJ (suzuki) or N3EJ/N3CJ (Ktm). You should be able to source all 4 needles for less than $50 total if you shop around. Pilots in the range of 172-178 should have you close. A 40 and 42 pilot should have you covered.

[roverhybrids]

I haven't figured out the holygrail for the RB ASII carb, but I changed the RB mod'd slide back to a standard #7 notched slide and that fixed the mid bog.
I think I have the N3EJ#3 w 40p and 178m. I needed a 38p for 4000ft ele in the summer with temps in the 90'sF.

[rocky2by]

Ok yes, it did have the N1EF needle stock. I'll look through my needle options and jets that came with the bike and what Ron included, I'll also pick up the other needles to have on hand. I did want to add that I'm at about 1800' feet where we live and mostly ride from sea level and up to about 4-5K feet, I'm glad I'm getting around to learning about setting this carb up, just been kind of lazy about having to do it. Also is there a good diagram of this carb?
Thanks, Steve.