4k stumble!!!! Im stumped!!!

[Vmaxattacks]

Are you certain you do in fact have the stock slide springs? The reason I ask is because I had at one time a set of Cobra slip-on's [insert flame comments here!] and I made the mistake of buying their "jet kit"..what a POS!
It was actually a re-packaged Dynojet kit made for them similar to the stage 1. I drilled the slide holes too but I also had put in their supplied slide springs. They are a bit shorter than the stockers. Anyway, after dealing with all of the general bad running issues (I too had a cough & stumble) and lost HP, I put all of the stock jets back in and I put the stock cans on after drilling the end caps. I experienced a hesitation much like you described. I got a new set of slides and the problem resolved itself!
Maybe the increased diameter bypass hole in the slides are causing you some grief...maybe the springs too.
Just a thought.
BUd

 

[65fury]

Hey there, you positive they are stock springs(about 8-9 inches i believe) I didnt drill the slides or do anything that was the PO and so far thats what seems to be causing all my grief, the slides open to quick. So im gunna throw some lager PAJ2s in(180s) and see if that helps lean it out, Im also going to probably end up epoxing my slides and redrilling them to the correct size. since making the slides open slower is making it run better.

Jason

Are you certain you do in fact have the stock slide springs? The reason I ask is because I had at one time a set of Cobra slip-on's [insert flame comments here!] and I made the mistake of buying their "jet kit"..what a POS!
It was actually a re-packaged Dynojet kit made for them similar to the stage 1. I drilled the slide holes too but I also had put in their supplied slide springs. They are a bit shorter than the stockers. Anyway, after dealing with all of the general bad running issues (I too had a cough & stumble) and lost HP, I put all of the stock jets back in and I put the stock cans on after drilling the end caps. I experienced a hesitation much like you described. I got a new set of slides and the problem resolved itself!
Maybe the increased diameter bypass hole in the slides are causing you some grief...maybe the springs too.
Just a thought.
BUd

 

[vmax626]

I had the same problem with my bike and it turned out being that the slow pilot jets inside the jet block under the small rubber plug were the wrong kind.
The right ones are supposed to look like a straw but the ones I had were more like a sprinkler head (closed at the top and a bunch of holes on the side) so we replaced them with 42.5`s abd the bike ran like a beast , no more stumble and power all the way up tach from bottom to top end.You`ll have to take your carbs apart again but it`s worth looking into.
Good luck,
<<Dave>>unk:

 

[65fury]

Well actually after pulling the carbs apart the second time i checked all my jets and I made sure i had all the correct and stock jets. I still have the stock 37.5 in there:biglaugh: Since going larger on that jet what do you gain? 42.5 is a bit bigger than 37.5 just curious, now that ive played with these carbs so much in the past 2 weeks im interested in playing with more jetting(after my trip) and seeing what happens. thanks

jason

I had the same problem with my bike and it turned out being that the slow pilot jets inside the jet block under the small rubber plug were the wrong kind.
The right ones are supposed to look like a straw but the ones I had were more like a sprinkler head (closed at the top and a bunch of holes on the side) so we replaced them with 42.5`s abd the bike ran like a beast , no more stumble and power all the way up tach from bottom to top end.You`ll have to take your carbs apart again but it`s worth looking into.
Good luck,
<<Dave>>unk:

 

[65fury]

Well i jb welded the holes and redrilled new ones using a 3/32 drill bit, went for a ride and my mids still dont seem right, my bottom end definantly pulls harder but then my top end will actually stumble at 6k when i whack it. I get popping from teh exhaust when down shifting also. If i open vboost(its controled by a switch now) the mids dont get any better and if i choke they still dont get better, this leads me to believe the slides are still opening to fast causing a rich midrange?? Im gunna try a larger PAJ2 maybe a 175 or 180. Any other ideas??

jason

 

[vmax626]

I am running the Marks pipes header system with Seans muscle jet kit.
My mains:162.5
p.a.j.#1 ::100
air correctors
p.a.j.#2 ::170
Diaphrams drilled.
stock needles shimmed w/ 2 washers
pilot (slow jets) ::42.5
A/F screws 3 1/2 turns out.
air box top cut and high flow k & N filter
installed by Sean Morley.
float bowls set at 17mm.
<<Dave>>unk:
I have extra jets ..165, 150, 155, 157.5, 147.5. all are mikuni`s.

 

[65fury]

Hmmm i like your setup, well ill probably put the 165 mains back in after my trip, but the 155s work fine for now, after drilling out a spare set of 170s for my PAJ2 drilled out to probably a 175.5 my midrange stumble is slowly getting better so im gunna drill them out just a hair more and see what happens. Altho i feel like my topend isnt plling as hard and seems to ome on later than before... any ideas why?? thanks


Hey dave wheres ontario at??

jason

I am running the Marks pipes header system with Seans muscle jet kit.
My mains:162.5
p.a.j.#1 ::100
air correctors
p.a.j.#2 ::170
Diaphrams drilled.
stock needles shimmed w/ 2 washers
pilot (slow jets) ::42.5
A/F screws 3 1/2 turns out.
air box top cut and high flow k & N filter
installed by Sean Morley.
float bowls set at 17mm.
<<Dave>>unk:
I have extra jets ..165, 150, 155, 157.5, 147.5. all are mikuni`s.

 

[Vmaxattacks]

Hey dave wheres ontario at??

jason

35 miles east of Los Angeles

 

[65fury]

hmmmm small ride:biglaugh: Ill check on my route to Texas and see if im heading thru there on my way back, BTW what does going larger with the PAJ1 do fo ryou??? low end, mids??? thanks

jason

35 miles east of Los Angeles