I'm having an issue with the sled not wanting to rev past 3k-3500. its an 89 EX570, i ran it with the belt off and same thing ( i know i shouldnt run it with the belt off but I had to see what it was doing) it idles just fine, i just cannot get it to rev up and it starts bogging, i've read all the other bogging threads and couldnt find anything with my set up. i've gone through the entire machine and this is what I've got.
145-150 psi on both cyls,
all new fuel lines, fuel pump, fuel filter, fuel tank has been cleaned.
PSI single pipe,
SX style y-pipe with the 20mm removed.
38mm flatslides from a 94 Vmax 600.
Comet 108c clutch.
the problem is within the carbs or possibly the clutch. the sled sat for 3 or so years before I restored it and i don't know if the clutch could be seized up or not, but you'd think it would still be able to rev with the belt off correct? I'm pretty sure the TORS is functioning. i disconnected the throttle switch to check it and it would kill everytime i hit the gas. to me that tells me that the carb switch is operating correctly. I've got 160 mains, is this way too much fuel? 50 pilots and i'm not sure what the clip position is on the needles. stock mains for the vmax 600 is 156.2, stock mains for a exciter SX with flatslides is 155. i jetted up because of the pipe but could I have gone too far up? would the mains even affect anything besides WOT? i need all the input I can get on this, going up north in a few weeks and i'd like to have time to play in the snow before i take it on a trip. I may ditch the old 108c and go for a different setup, i'm sure its long worn out by now. any recommendations for a good primary on this thing? THANK YOU
145-150 psi on both cyls,
all new fuel lines, fuel pump, fuel filter, fuel tank has been cleaned.
PSI single pipe,
SX style y-pipe with the 20mm removed.
38mm flatslides from a 94 Vmax 600.
Comet 108c clutch.
the problem is within the carbs or possibly the clutch. the sled sat for 3 or so years before I restored it and i don't know if the clutch could be seized up or not, but you'd think it would still be able to rev with the belt off correct? I'm pretty sure the TORS is functioning. i disconnected the throttle switch to check it and it would kill everytime i hit the gas. to me that tells me that the carb switch is operating correctly. I've got 160 mains, is this way too much fuel? 50 pilots and i'm not sure what the clip position is on the needles. stock mains for the vmax 600 is 156.2, stock mains for a exciter SX with flatslides is 155. i jetted up because of the pipe but could I have gone too far up? would the mains even affect anything besides WOT? i need all the input I can get on this, going up north in a few weeks and i'd like to have time to play in the snow before i take it on a trip. I may ditch the old 108c and go for a different setup, i'm sure its long worn out by now. any recommendations for a good primary on this thing? THANK YOU
extreme4max4rules
New member
when u get the revs to 3500 did u try flipping the choke to see if it takes off or starts to load up on fuel, how strong is ur spark, u may have ignition problem or fuel related, ive got a exciter with over 14,000 km which is over 10,000 miles . when is the last time u did crank seals, if uv got a bad seal u will not build crank case preesure which is needed for good vacume to run ur fuel pump, to check ur crank seals to see if they are good get ur self a can of starting fluid or we call it either, while the engine is running at 3000 rpm spray the starting fluid at the crank seal on the pto side and mag side if the engine picks up rpm when u spray it thier then u have bad crank seals, just my 2 cents Al LARSON
i flipped the choke and it loaded up with fuel, it starts on the first pull even when it sits a few days so i don't think its a vac problem, but i'll check the seals. can they be done without splitting the case?
try raising your clip 1 notch on your needle.(lean the midrange) i believe you are too rich in the midrange. i would also put the 155 mains in, dont forget you do not have a sx engine(wilder porting that needed morefuel)so the 155 should be closer to what you need with stock engine with pipe combo.i believe you are too rich! how does your plugs look now?but remember just do 1 change at a time so you know you are headed in the right direction. i would do needles first.
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800
New member
No, no, if it's not the TORS, it is just way too rich in the middle, the 600 carbs are for a reed valve engine with a boost bottle, they are going to be way richer than the SX carbs, SX carbs had a much leaner needle for the piston port motor, not to mention the SX made 15 more HP than the EX, if it is so bad that it does this on the jackstand and its not the tors, drop the needle all the way down, with like 152.5 mains and see if it gets better. I may have the needles for that, I stripped a buch of those carbs way back when.
i'm a bit confused, ramblin man says raise the needle to lean the midrange and 800 says drop it to lean, which way is it? also 800 are the SX needles physically different than the needles used on the 600? or is just the clip position different? I did use this setup on another 89 exciter I had but i think those carbs were from an SX, so the settings were probably closer to what i needed than the VX600 settings.
800
New member
yes the sx needles are different so are the nozzles, from a 600 carb.
Who's right? Only you can tell by testing it on the jackstand, but like you said, when you played with the choke it dropped hard.....it's rich, drop the needles all the way, if its better you need the correct parts.
Who's right? Only you can tell by testing it on the jackstand, but like you said, when you played with the choke it dropped hard.....it's rich, drop the needles all the way, if its better you need the correct parts.
i won't have time to play with it today before work but the yami dealer is right across the street from the dealer I work at so i'll just order the correct nozzles needles, and probably a couple main jet sizes and hopefully i'll be able to get her dialed in tomorrow. thanks for the help :thumb:
well i just ordered all the SX goodies for the flatslides, needles, nozzles, main and pilot, even got some new choke plungers and springs to rule that out. at just over $100 for everything hopefully i can get it running better, and if i have to i can dial it in with clip changes and some minor jetting changes.
You Need To Go Back And Read It Again, I Did Not Say Raise The Needle! I Said Raise The Clip!!
ramblnman said:
yes i realised this after i posted, raising the clip effectively lowers the needle causing the midrange to be leaner, and vice versa corret?
extreme4max4rules
New member
u are rich for sure and 800 is right on with the different needles at 155 mains i think thats rich to , but u have a interesting combo but once u get the right jets im sure its going to rock , Al Larson
well the needles finally showed up, but BOTH were damaged in transit. the ends have a slight bend to them like they were somehow tweaked.... looks like i'll probably be out for the last two weeks of the season.
800
New member
what are the numbers on the sx parts, I should have them in my drawer of needles and nozzles.
Tell me this am. I'm going on vaca for a week Thursday.
You had 600 carbs? check the numbers but I think they both had 2.5 slides, or the sx had 3.0's, really taxing my memory now.
Tell me this am. I'm going on vaca for a week Thursday.
You had 600 carbs? check the numbers but I think they both had 2.5 slides, or the sx had 3.0's, really taxing my memory now.
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9EL02 is the jet needle number but cant tell you what the slide cutaway was
800
New member
the only way I think you can tell the slide number is in the service manual, I'll have to go dig it back out.
800
New member
well it's a 9EL2 in the 3rd clip, does not list the nozzle, and I can't believe I don't have any, got a dozen 500/600 needles Z3/Z4, the slide on the SX is a 3.0, the long slide, the 500 has a 3.0 and the 600 has a 2.5, 95 and 96's had the short slide.
What you need to find is an actual set of 8AY carbs, I'll see what I can find in the am.
What you need to find is an actual set of 8AY carbs, I'll see what I can find in the am.
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located a set of needles, they are the 9EL2's, not sure what the nozzle was, but it was the SX nozzle. i didnt write it down before i installed them. whats the difference in the slides? is it going to cause a problem if i have the vx600 2.5 slides? so what else was different between the 8AY carbs (SX version I assume) and the 94 600 carbs? just the internals? I now have everything set up to SX specs, pilot, main, needle, nozzle except i'm just learning the slide's are different.... i'll be starting it up probably tomorrow sometime. Just getting my handlebar situation figured out. if i get all the little bugs worked out we're taking it up to hurley for a little weekend fun on the 28th. i hear the snow up there is still decent.