#553

[gixxer6]

It will now run a fairly consistent 7,000 max rpm.

Doesn't sound right.  Looked in the service manual and it should be running around 8200-8300 max rpm.  Have you checked your clutches or checked to make sure the slides are opening all the way?

I built the primary clutch for this sled.  It is all stock with all new bushings.  I did take it apart to double check everything was still in place. 

I don't recall what all was done with the secondary.  It's been awhile since I have messed with this sled.  I will take a closer look at it. 

Thanks for your input. 

[kawhead]

if you see an improvment with smaller jets/cooler temps it leads me to think leaner will help....sounds like you are getting extra fuel somewhere....

[gixxer6]

Update: 

I dropped another 20 points off the mains.  It isn't perfect, but it's ALOT better.  It'll pull almost full RPM.  It'll bog off the line, then pull the skis, up til about 7,800 RPM, then it'll slowly gain RPM up to around 8100.  Which is still a little low, but at least I know I'm on the right track.  I'm going to drop the needle one clip, and maybe the main another 10 points.  I'm a little confused why others are running 350 mains, and I'm all the way down to 310's???

[Trucker]

You are running with and airbox right? I had 340's with velocity stacks and its was a bit rich. with and airbox i ran as low as 270's

[gixxer6]

You are running with and airbox right? I had 340's with velocity stacks and its was a bit rich. with and airbox i ran as low as 270's

Ahhh...  That explains it.  Thank you.

[gixxer6]

Trucker,  Do you remember what pilot, needle, and needle jet you ran when you had the airbox on?  Thanks. 

[Trucker]

Same and only once because it ran crappy with it.

[gixxer6]

Ran crappy with it?  The airbox??? 

[Trucker]

yes it ran crappy with the airbox so i just used the velocity stacks

[gixxer6]

Trucker, were you running 38's or 39.5's? 

I switched my airbox for velocity stacks and installed 350 mains.  It is WAY better.  Thanks again for the info.  Here is where I am at: 

350 main
2.5 slide
6DH2 middle clip
Q-0 needle jet
40 pilot

It runs fairly good, but isn't quite right yet.  I'm going to try a fresh set of plugs, the current plugs have been through the ringer while jetting it.  They've been fuel soaked countless times. 

I don't like the extra noise with the velocity stacks.  Anyone every try running a gutted airbox???

[Trucker]

I had 39.5's and yes the extra noise is annoying. go bax to using your airbox but make sure its cleaned out good inside and try smaller jets until its right.

[gixxer6]

New plugs installed.  Its sluggish off the line, but after the first 10 feet it pulls hard and runs a good 8,300 rpm.  The plugs look light brown, but it was REALLY cold when I ran it.  The 350 mains should produce a nice chocolate brown in warmer temps. 

Any ideas why it'd be sluggish out of the hole?  Maybe they're all a little sluggish??? 

I am toying with the idea of rebuilding the stock Keihins, just to get a baseline of what stock performance is. 

[wildwolf]

Air screw and pilot jet affect off idle performance. My 550 cats had the same carbs with #35 pilots and about 1/2 turn out on the air screw. Might be worth a try?  The air screw is very sensitive to small adjustments but really cleans up the bottom end.

Good Luck

[wildwolf]

Air screw and pilot jet affect off idle performance. My 550 cats had the same carbs with #35 pilots and about 1/2 turn out on the air screw. Might be worth a try?  The air screw is very sensitive to small adjustments but really cleans up the bottom end.

Good Luck

Me again, screwing in the air screw makes it richer-out leaner(more air) you have 3 turns of adjustment. The ideal setting is about  1 - 1 1/2 turns out putting you in the middle of the adjustment for that circuit. Just keep changing the pilot jet until you get to that.

Kevin

[Kawasaki Powered]

Just as a baseline, I cleaned the stock carbs on mine last night. I then took it out and put a few miles on it as I am heading to a vintage ride with it today. It runs very strong pretty much right off the line. It will spin the track off idle. The problem I'm having and maybe it's just old technology but off the line she pulls hard and rocks out nicely. After I get to a nice cruising speed of about 30 or so then punch it, it's a little boggy until the motor ramps up again. I believe mine is a clutching issue with a sluggish backshift. I've never had my secondary apart so I don't know if I would benefit from a clean up or if this is what to expect out of old technology.
As a side note, I have talked to many who say that they could get their 550 running good with the Mikuni's but never quite as good with the stock butterflies. That's why I have stuck with the stockers even though they are a pain to take apart and clean and are harder to find parts for.

Robb