Well fellas, I'm getting closer to dialing in my 720 and had a question on jetting. Right now I have a 145 main, 97 needle clip 2, 35 pilot, 50 accel. pump with shortened pump rod, 2.5 turns A/S. I think I'm pretty much ok if not a little fat up top but was wondering if anyone has gone leaner than 145 for the main? I'm at 2000' with temps in the 60's & low humidity. 3 gal. 100 octane with 2 gal. 110. Plug is still a tad rich & carbon builds up quickly on the exhaust flange. Bike also emits a nice puff of smoke when I crack the throttle open from idle (may be the accel. pump's effect). It's prolly all in my head about going smaller than 145?[img]i/expressions/face-icon-small-blush.gif[/img]

 

Does that pilot come that size stock for 45mm??seems lean..I run air fuel 1.5 turns out with good results, try to lean out needle all the way...It is hard to get a good plug reading with accelorator pump...I dial my bikes in with temp guage and..It may be the wrong way but at least youll know when shes runnin too hot.

 

Stock pilot was 40, 35 is still too fat even at 2.5 turns out on the A/S, going to try next step leaner soon as I get one. I had the needle (97) in the 1st clip but was worried about being too lean. How 'bout some feedback from all you 720 built guys out there? Maybe I need a leaner main because I have stock valves & mild cams (RWR sport) so I'm not flowing the same amount on top end as the folks with big valves & radical cams?[img]i/expressions/face-icon-small-confused.gif[/img]

 

I have seen 720s run with a 140mj at sea level and with your elevation it should be ok, just dont let her overheat that will cause bad probs. Im sure you know this. If you feel good about your needle placement and it still looks rich on plug, Definiatly go with smaller main, it should still pull hard on top with those sport cams and stock valves if dialed right. good luck.

In my history of jetting with needle in the middle position, when bogging on the big end It always helped when I went leaner on main jet.

 

You seem to have a grasp on these 720's, what kinda setup you runnin'?

 

i run 142 and plan a 140 soon

 

What valves / cams are you running? Am I way off or does it make sense about me having stock valves & mild cams, therefore not flowing as much up top & not needing as large a main? I'm not sure how many 720 owners are using stock valves & sport cams, but I can tell y'all this........what a torque monster! I mean this thing grunts off idle like a blown big block, especially with the accel. pump activated. Can't wait to get the 760 crank in there![img]i/expressions/face-icon-small-smile.gif[/img]

 

i have the big valves in mine.