Unusual Sensation at 5k rpm on highway ~75mph.

[hootmon]

I had the Dyna-jet kit in my Project 96 Magna with 100 main jets and 42 pilots, with K&N, and Supertrapps, worked GREAT! 

And a sweet bike it was.. Of course in the FASTEST color I might add.. (same as mine)

[tedkraus]

Interesting stuff, carbs seem fairly complicated. I know at the low end I am running maybe a tad lean with some slight popping on decel, but I just switched the plugs and they were very sooty. So I was thinking it was rich, but from what you guys are telling me it almost sounds lean. I am not sure why I put the DJ096 in vs the DJ100, I think it was the local mechanics recommendation.

How long till I should pull a plug and read it, its been maybe 150 miles. Also maybe it could be a carb synch issue because I have very little idea of how close they are at the moment?

Thanks!

[Greg Cothern]

Decel pop in moderation is normal.  In excess its lean.  Non existent is too rich.

[tedkraus]

Yeah Greg, I think my decel pop is very moderate. But the question then is how long should I wait until pulling and reading a plug. I honestly think the bike is rich through most of the range except 5k based off this discussion.

[Greg Cothern]

Best is to find a dyno day at a local dealer and get them to sniff it while your checking HP #'s.

But if you do not want to go that route I would say couple hundred miles.

[Chad in Michigan]

Hello everyone! It has finally been nicer in MN! I noticed something odd on the interstate today wondering if anyone has some input.  Around 5k rpm cruising in 5th gear if I "hit the gas" so to speak the bike momentarily seems to pull hard, bog and pull hard again... If that did not make sense let me explain one more way, when I go WOT at 5k rpm in 5th the bike seems to rapidly accelerate, hesitate for a second and than accelerate again.  This all happens in just a second or two,  and I am not trying to refer to the typical dead spot at 5-6k rpm. I cannot recreate this problem below 4800rpm or above 5200pm, if I go WOT at those RPM it just pulls like it should with no unusual sensations right through 5k with no problems.  I can also recreate this problem in other gears like 4th and I also think 3rd. ( I get pulled back initially, pushed forwards, and then pulled back again all in a very brief time frame in my opinion under 2 seconds)

Extra info : I have been running 91 octane, with a small dab of seafoam the past few tanks, the bike idles fine after 10 seconds or so (50-65F outside), and there is no "surging"  when not under stress like in neutral.  The bike has K&N filter, cobra pipes, and has a cobra jet kit.  Also for those who helped me previously the coolant system continues to be fine after the winter problems you guys helped me with earlier no loss of fluid smoke etc.   

Could this be the jetting? Carb synching? Chain (seems good tension to me)? Gunk in the carbs from winter still?  Clutch briefly slipping and catching again? Also I am at about 14.5K miles?

Happy Riding!

maybe it is a little rich at midrange? when those jet kits first came out, the instructions had you set the needle clip position too high and resulted in a muddy midrange.

[tedkraus]

1) problem no dynos at any dealership etc within 170 miles...

2) im not sure I want to go richer on the fuel mixture as the plugs are all ready starting to soot up. About 300 miles after install.  Im honestly very confused if the surge at 5k was main jets are lean why are my plugs sooted up? Most of my miles are 55mph+ country roads.