Loss of top end Poo 600 IQ HO

G

G13

New member
got an 07 polaris iq 600 ho carb that has a top end of about 80. i am out of ideas with this thing and at this point will be making an insurance claim on it next year. ;) JK... anyway. the top rpm is 7900, it is stock gearing. replaced primary and secondary springs. rolers and weights are good, maybe need lighter weights to get rpm up but sled should still be faster then 80, it would do 103 when she was new. i have changed some carburation but even at stock the missing top end persist. what i have now is 410 mains with 40 starter jets, stock is 420 and 50's. does have a low end bog if i go to wide open throttle from stop. if i feather it goes just fine.

I was cleaning the ves valves and the cap that holds the guillotine striped out and the guillotine was just sitting down and never moving and actually had a chunk break off and fly into exhaust which i was able to retrieve. ordered new parts and thought for sure that would solve my problems but no, it did not. i am loosing my mind with this thing.

how do i test the exhaust valve solenoid? it ohms out at 13.9 and should be 15 so that should be okay. Should it be open or closed with the sled running. I can not blow through it with the sled not running. i realize it does close or shut till 6800rpm or so.

belt has 700 miles on it but compared to a new one i got and seems in good shape. same size and everything.

hope you guys have some ideas, i am out and getting tired of this beast.
 
P

Polarice

New member
What's the TPS like? I have an '07 600 HO and when I bought it used (from a reputable J'de'r (aka Dave B)) I had my service guy go through it. The tps was off, but more so the throttle itself was off. It's hard to say how long it was like that but it wasn't able to get full throttle.

I would check that. I believe that it will go somewhere around 95 on top end. We're not into topping out sleds but I know it's been past 90.

Hope this helps.
 
G

G13

New member
No can.
compression is good in both cylinders. i checked them after i noticed the broken guillotine.
The cable throttle itself opens the carbs up all the way. i have not read the what the TPS is doing.
 
R

rp7x

Well-known member
carb boots

make sure they are not ripped apart my were one of my valves lost a nut also , i have the vent after the solinoid plugged
 
G

G13

New member
ok
worked on it a little more this weekend and am officially ready to give up.
spark is good. ves bellows are good. cleaned the ves ports to the cylinder and valve. everything is now practically sparkling in te ves area. have yet to plug the end of the hose for the solenoid, maybe try that tonight before the snow is gone.
 
D

Dave_B

Active member
Polarice said:
What's the TPS like? I have an '07 600 HO and when I bought it used (from a reputable J'de'r (aka Dave B)) I had my service guy go through it. The tps was off, but more so the throttle itself was off. It's hard to say how long it was like that but it wasn't able to get full throttle.

I would check that. I believe that it will go somewhere around 95 on top end. We're not into topping out sleds but I know it's been past 90.

Hope this helps.
Click to expand...

When I had the sled, although he said the TPS and throttle were off, I had no top end issues. I'm not a WOT kind of guy but never had an issue hitting 90+ per the speedo on a nice hard packed trail even after I put an 1.25 track on it. I did run 93 octane in it as much as possible. Don't know how much effect that had but... I think you have other issues going on.

Dave
 
C

cpaum

New member
The bogging out at take off can be anything. Looks like you checked the motor out pretty good. There are a couple easy things to check and make sure you double check.

Is your belt good? What belt are you running? Check your motor mounts? Take a marker and mark a line on the Sec. clutch. Make sure you are getting it to shift all the way (opening up) when you are riding it. If you see marker that's where the shifting stopped. Also mark it on the prime to make sure it is closing all the way so it will shift. If the marker is gone on the prime and not on the sec. You have a belt problem, mount problem or your clutches are not spaced correct.

How tight do you have your track? If a track is way to tight you will loose top end fast. But wouldn't explain the bog.


AIR BOX. Make sure everything in the air box is clean and not restricking air flow.

You said this was a 600 hi carb sled. Where are the needles at?

Make sure your pipes are clean and a mouse didn't go up and place nuts inside.




If everything is good there. Please explain the bogging a little better. How bad is the bog?
 
G

G13

New member
its not like i need to go 90+ either but the mid range pull is missing as well. it is not the same sled she was new.

i will have to try the marker trick - good idea
Track is actaully pretty loose, i put on a 1 1/2 ripsaw about mid season, yes sled has been boggy all year and last year for that matter.
needle clip is second from the bottom. 410 main jets, 420 are stock. newer sleds are running 400's with clip up one higher.
airbox is good and exhaust is good, i dug out the part of guillotine from the bottom exhaust box.

the bog is only if i go to WOT from takeoff it feels like a rich stumble but i'm not expert, it is worse if i choke it.
i always run the higher octane, 91 is what is around here.

hope it isnt the crank seal. to test that, can i just spray carb cleaner or something around the seal.
 
A

acatzl550

New member
G13 said:
its not like i need to go 90+ either but the mid range pull is missing as well. it is not the same sled she was new.

i will have to try the marker trick - good idea
Track is actaully pretty loose, i put on a 1 1/2 ripsaw about mid season, yes sled has been boggy all year and last year for that matter.
needle clip is second from the bottom. 410 main jets, 420 are stock. newer sleds are running 400's with clip up one higher.
airbox is good and exhaust is good, i dug out the part of guillotine from the bottom exhaust box.

the bog is only if i go to WOT from takeoff it feels like a rich stumble but i'm not expert, it is worse if i choke it.
i always run the higher octane, 91 is what is around here.

hope it isnt the crank seal. to test that, can i just spray carb cleaner or something around the seal.
Click to expand...

yes spray carb cleaner or starting fluid around the seal by the clutch, but if it doesnt affect the engine, it could still be the mag side seal, and you will have to find the hole in the crank case to spray it in there to get behind the stator assembly
 
G

G

Guest
Put a new belt on it. You might be making this too complicated. Pol has known issues with belt glazing. 700 miles is not new anymore.
 
D

dakota

Member
if you exhausted all of the issues with clutching and engine, you should looked beyond. is something dragging excessively in the drive train. Raise the lower end and grab the secondary. how much drag do you have when you try to turn the secondary. does the track turn freely. Loosen up the track so you can spin each of the wheels to be sure you don't have wheel bearings dragging. i've seen bad jackshaft bearings and or bearings in the skid cause a lot of excessive drag, certainly enough to hurt acceleration and top speed.
 
C

cpaum

New member
What do the plugs look like? Are they running rich or lean? How many feet above sea level are you. Also let me know what the clutches are doing after you try it.

You might have a fuel mixture problem. Which we can adjust on the carb.
 
G

G13

New member
pretty sure MN is less then 2000 feet above sea level. plugs have been black and rich and now with the warm weather and rain we are getting now a plug test is a mute point i am thinking.

i will do marker test hopefully tonight, kids has baseball practice already, but carb setup i want to almost rule out since i set it to stock and the problem persisted. I am more and more thinking it has to do with missalignment of clutches or somewhere there abouts. i must admit to that when i took off the secondary i may have missplaced a space washer. any advise on how that could be tested for alignment or how the secondary should sit.
 
indy_500

indy_500

Well-known member
missing a washer in the secondary will not make it lose top end. Could lose some snap if a lot of washers were missing.
 
R

rp7x

Well-known member
poor clutching

it would be like going up hill in high gear, not very good , if you have a nother secondary try it first
 
M

mikeh906

New member
There are two small air lines to the air box, make sure they are still connected. I had one fall off and my sled ran like your describing.
 
You must log in or register to reply here.
Top