Ok here's the deal. I have the Laser full system, K&N drop in. I am running #20 pilot's, 62.5 mid's, 137.5 mains. The bike starts idles and runs great until I hit 10k rpm under hard accel. then it is like somebody hits the kill switch. I just shift at this point, but I was wondering what the expert's think this could be. It has pretty much done this ever since I put the pipe/filter and jet kit on. I gave up on the DynoJet kit because I could never get a roll on dead spot out of it. I have checked my floats and adjusted them accordingly. I am assuming this is a main jet problem because of the high rpm or is it something non jet related? I will try and change the mains tomorrow to see if it helps. Any ideas welcomed. 

Nope, mains should do it.    But, after peak hp that's what it feels like.

Quote from: Jason on June 17, 2006, 09:35:46 AM
I gave up on the DynoJet kit because I could never get a roll on dead spot out of it. I

? What does that mean? I just ordered a Dyno kit for my 95? I have a full V&H and KN Lunch box.. do you think I will have trouble?

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Yeah, you're near redline at that point. That's normal. If it kept pulling hard at 10, I'd ask what year's R6 motor you had in that GS fame.

Dave 

Quote from: Jason on June 17, 2006, 09:35:46 AM
The bike starts idles and runs great until I hit 10k rpm under hard accel. then it is like somebody hits the kill switch.

There's your problem.  Too much testing.  You see, you were supposed to report back only that the the bike starts, idles and runs great and everyone with reservations about DIY jetting is a dunce!  

I can think of two conditions that can make power drop off precipitously at 10k:  Valve float and rich jetting.  Since redline is >11k I'd go back to the stock MJ's and see if the condition persists.        

You forgot to mention fuel starvation.  I'm running into that now on my 95.  40 pilots, 125 mains, stock pipe, stock air filter, 2 shims, 3 1/2 turns.  No more stumble, turn off the choke after about 20 or 30  seconds and ride away.  Top end is responsive, good roll on.  But now, when you roll it on in the higher gears, it takes right off, when you let off and roll back into it, there is a hesitation, just for a second.  I am almost sure it is fuel starvation.  I am going back in there to check the floats again.  And the tanks stays on prime.  When using reserve or the main tank, the carbs will run out of gas after a long high speed run.   Any other suggestions?

Quote from: corndog67 on June 17, 2006, 07:21:16 PM
But now, when you roll it on in the higher gears, it takes right off, when you let off and roll back into it, there is a hesitation, just for a second.  I am almost sure it is fuel starvation. 

Nope.  Too fat Corndog.  Back off and dial it on <stumble> = rich.  Back off <surge> = lean.  By shimming the needles you have run afoul of the law of unintended consequences.     You should remove a shim, and there's no reason for the oversized mainjets on an otherwise stock setup.  Again, DIY jetting does not stand up to this close scrutiny.   

Quote from: scottpA_GS on June 17, 2006, 10:24:56 AM

Quote from: Jason on June 17, 2006, 09:35:46 AM
I gave up on the DynoJet kit because I could never get a roll on dead spot out of it. I

? What does that mean? I just ordered a Dyno kit for my 95? I have a full V&H and KN Lunch box.. do you think I will have trouble?

I can tell you that the setup they list did not work for me. I had a dead spot after I would let off and roll back in the throttle in the mid rpm's. This has been said to be a rich condition. I changed the needle clip's down and up to try and figure out if it was lean or rich, but it never took the dead spot away no matter what I did. I changed mains up and down and it never went away. I tried to compensate lean and rich on evey circuit I could and it didn't work for me. I am at about 1,500 ft. elevation.

Quote from: My Name Is Dave on June 17, 2006, 11:51:53 AM
Yeah, you're near redline at that point. That's normal. If it kept pulling hard at 10, I'd ask what year's R6 motor you had in that GS fame.

Dave

Yeah, I know the power flattens out at about from 9k-10k  rpm ,but I never had a probem making it to 10k before. It will actually start to stumble around 9,500 rpm at times. I am not sure if it is lean or rich.

It does feel like valve float. That would be exactly how I'd describe it, but why coincidentaly after I change pipe/filter/re-jet? I have ran it to 10K lots of times before no problems. I'll try to drop the mains tomorrow back to stock and see what happens.

bike should pull clean through to 11k
not har after 10k but still pull
peak HP is at about 10k

valve float...sounds like ball bearings in a tin can....even with ear plugs!!!!!!

10 K....MAIN JET ONLY

if you don't know.......
go up or down....2-3 sizes ...... pick one

better or worse.....
of worse....go the other way

Nope.  Too fat Corndog.  Back off and dial it on <stumble> = rich.  Back off <surge> = lean.  By shimming the needles you have run afoul of the law of unintended consequences.     You should remove a shim, and there's no reason for the oversized mainjets on an otherwise stock setup.  Again, DIY jetting does not stand up to this close scrutiny.   

Quote

Plugs are looking good.  I forgot to mention that recently, the bike is running the carbs out of gas.  If I pop the cap on the tank, they fill right back up,  I guess a venting problem. 

Before I put the second shim in, it was still a little lean off the bottom.  With the second shim, the rideability is much better.  I know what you're saying about the stock pipe and overrich mains, but right now, other than the rolling off, rolling on hesitation, it is much better than it was.  I will mess with it tomorrow and get back with results later.  Thanks.

I dropped the mains down one size to a 135 and it made it a lot better. Cold bike and 62* it pulled hard right up to redline. After the bike got warmed up good I could feel it start to choke out at abot 10,500, but it still pulls a lot harder up to that point. I think 132.5's are gonna be my best jet but I don't have any. Of coarse I ordered 135-140 from sudco when I ordered them figuring I would need atleast a 135. 

8f

Quote from: Jason on June 18, 2006, 05:59:12 AM
I dropped the mains down one size to a 135 and it made it a lot better. Cold bike and 62* it pulled hard right up to redline. After the bike got warmed up good I could feel it start to choke out at abot 10,500, but it still pulls a lot harder up to that point. I think 132.5's are gonna be my best jet but I don't have any.

So, 137.5 killed power, 135 is still too rich to pull cleanly through redline, and it's fair to say that 132.5 is the richest jet that will allow for glitch-free performance.  The stock mainjet size is 130 and should be fine (the richer jet will sap power when riding at altitude that much sooner).

I think there's a lesson here:  The OP has a Laser racing pipe and a K&N drop-in filter and the OP's trial & error jetting observations seem to indicate that no mainjet change was even required.  This runs counter to the conventional wisdom here which insists that, since stock jetting is borderline lean, a pipe & drop-in filter upgrade desperately requires larger than stock mainjets to feed the de-restricted flow of air.  The test results are in; a myth has been momentarily dispelled. 

you shouldnt be shifting at 10k you already past pek power, at 10k revs it drops to about the same as 8k revs
peak is at 9.2 you should shift at about then.
only my oppinion of course, ride it how ya want to

i pull redlines all the time    .... pulls hard threw every gear tell there .. well .. once i hit 5th it tends to not pull so much at all but ....... every gear before that

Quote from: hmmmnz on June 18, 2006, 12:10:24 PM
you shouldnt be shifting at 10k you already past pek power, at 10k revs it drops to about the same as 8k revs
peak is at 9.2 you should shift at about then.
only my oppinion of course, ride it how ya want to

Yes I agree. I do not normally ride it to red line. I was just doing it more for testing purposes. Actually when I'm riding it back and forth to work I'm shifting more around 6,500-7,000 to save gas.
I tried the 130 stock jets, but it just didn't pull as hard from 7k-10k probably a tad lean I'm sure so I put the 135's back in. I don't even think I'll bother with 132.5's. Like I said, it pulls great everywhere, but after it got up to 90* and the humidity kicked in I feel it start to bog at 10,500, but as mentioned before this is a useless part of the power curve anyhow. I'll stay a hair rich on the hot days and have perfect jetting anytime it's 65* or below