herndonp
TY 4 Stroke Guru
Is it also possible your water temp sensor is not reading correctly and keeping her on high idle because she thinks she is to cold. Like when you first start it up and she idles high. Just a thought.
Pete
Pete
newbb
Extreme
started and rode the sled today. sucks with the high idle but still is very ride able. Im going to mess with the TPS sensor angle once I get the correct star tools.
Shortly into my ride I realized my front shocks are completely shot/sacked. They sit all the way compressed and and stay that way. Ive had blown shocks in the past but these are blown so bad they do not rebound at all. Spring and shock all the way compressed. riding with zero front suspension is not fun.
I always thought the spring would at least hold the sled up? Or is that just with older yamaha 2-strokes because they are not as heavy?
Anyone have a pair of front 08 or 09 Nytro shocks they are looking to sell?
Shortly into my ride I realized my front shocks are completely shot/sacked. They sit all the way compressed and and stay that way. Ive had blown shocks in the past but these are blown so bad they do not rebound at all. Spring and shock all the way compressed. riding with zero front suspension is not fun.
I always thought the spring would at least hold the sled up? Or is that just with older yamaha 2-strokes because they are not as heavy?
Anyone have a pair of front 08 or 09 Nytro shocks they are looking to sell?
Beenba
TY 4 Stroke Junkie
The spring is what holds all the weight.
The shock is only there for dampening. aka once the spring starts to bounce.
If its stuck all the way down (and the spring is fully compressed or bottomed) it sounds like your shocks are so blown they are seizing up and holding the sled down (aka the force exerted by the spring is not high enough to overcome the force to move the seized shock) - hence why it sticks down. Either that or your A-arm bushings could be seized or springs fatigued.
The shock is only there for dampening. aka once the spring starts to bounce.
If its stuck all the way down (and the spring is fully compressed or bottomed) it sounds like your shocks are so blown they are seizing up and holding the sled down (aka the force exerted by the spring is not high enough to overcome the force to move the seized shock) - hence why it sticks down. Either that or your A-arm bushings could be seized or springs fatigued.
newbb
Extreme
Im pulling it apart tomorrow. Hope shock just needs a rebuild and my other linkage and spring is fine.
newbb
Extreme
Anyone have a pair of stock shocks for the 08 or 09 Nytro they want to sell? 17.5 eye to eye measure I think.
nate007
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Check to be sure your throttle cable is seated in the cam properly and that the throttle blades are completely CLOSED at idle. They're not like a car where they are cracked open at all to allow idle air, that's what the valve is for.
They do run a bit richer than an auto engine as well, so any air leak at all will cause a high idle. Check the throttle body boots to the head, the misc rubber plugs over the additional ports on the throttle bodies, and that the blades are closed. The main idle set crew is mainly there to keep the blades from sticking shut fromt the angle they close at, as well as minor idle adjustments, but generally shoudln't be messed with!
You've got an air leak somewhere.
There's several ways I can think of to check for an air leak while it's idling, but in the interest of safety, I'm hesitant to describe... Lol
I would try plugging the air temp sensor in, and with the airbox off, and the sled idling, put your hand over each throttle body and check to see if there's a vacuum, and/or if the idle drops.
To adjust the TPS, you'll need the proper torx bit and carefully loosten the two screws holding the sensor on the end of the throttle body. It's located on the left side. Looking at it from the left side, rotating it clockwise will lower the tps reading and counter clockwise will raise it. To move it the ammount you are saying you need to move it, the ammount will barely be noticable, so be very gentle. Might help to mark the sensor and t/b housing before you do so you know where you were when you started.
This would be a last resort though. If you've never moved it until now, that's likely not your issue!
They do run a bit richer than an auto engine as well, so any air leak at all will cause a high idle. Check the throttle body boots to the head, the misc rubber plugs over the additional ports on the throttle bodies, and that the blades are closed. The main idle set crew is mainly there to keep the blades from sticking shut fromt the angle they close at, as well as minor idle adjustments, but generally shoudln't be messed with!
You've got an air leak somewhere.
There's several ways I can think of to check for an air leak while it's idling, but in the interest of safety, I'm hesitant to describe... Lol
I would try plugging the air temp sensor in, and with the airbox off, and the sled idling, put your hand over each throttle body and check to see if there's a vacuum, and/or if the idle drops.
To adjust the TPS, you'll need the proper torx bit and carefully loosten the two screws holding the sensor on the end of the throttle body. It's located on the left side. Looking at it from the left side, rotating it clockwise will lower the tps reading and counter clockwise will raise it. To move it the ammount you are saying you need to move it, the ammount will barely be noticable, so be very gentle. Might help to mark the sensor and t/b housing before you do so you know where you were when you started.
This would be a last resort though. If you've never moved it until now, that's likely not your issue!
newbb
Extreme
But doesn't the fact that my 20 TPS reading in diagnostic mode at throttle fully closed indicate there is a problem with the TPS? Considering it should be at 16.
grizztracks
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The previous owner probably tried adjusting every screw he could find when the ISC went bad.
The idle screw is on the front of the throttle body (air box side) opposite of circled adjustment. It's a allen set screw with a jam nut. The sync screws are on top of each throttle body behind the vacuum line ports and have a recessed brass screw. Each sync screw allow air to bypass the throttle plate through a port in the body. The circled adjustment will open TB #1 (LH) if turned CW allowing air to bypass directly through the throttle body around the plate. It does not have any effect on TB 2 or 3 but if the screw is backed out CCW to far TB 2&3 will not fully close after being opened causing the throttle rpms to hang. The throttle override does not detect this because the TPS is on TB #1 only. I'm not sure of the proper procedure to adjust this screw but it's very delicate to set it correctly so little movements matter. TB #1 is very important in the setup because you sync the other two to it. The first step in syncing is to check vacuum level which if not correct then turning the screw in CW to open TB #1 blade will decrease vacuum and turning it out will increase vacuum.
The idle screw is on the front of the throttle body (air box side) opposite of circled adjustment. It's a allen set screw with a jam nut. The sync screws are on top of each throttle body behind the vacuum line ports and have a recessed brass screw. Each sync screw allow air to bypass the throttle plate through a port in the body. The circled adjustment will open TB #1 (LH) if turned CW allowing air to bypass directly through the throttle body around the plate. It does not have any effect on TB 2 or 3 but if the screw is backed out CCW to far TB 2&3 will not fully close after being opened causing the throttle rpms to hang. The throttle override does not detect this because the TPS is on TB #1 only. I'm not sure of the proper procedure to adjust this screw but it's very delicate to set it correctly so little movements matter. TB #1 is very important in the setup because you sync the other two to it. The first step in syncing is to check vacuum level which if not correct then turning the screw in CW to open TB #1 blade will decrease vacuum and turning it out will increase vacuum.
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newbb
Extreme
Adjusting that screw out ward will lower the TPS reading in diagnostic mode?
newbb
Extreme
and is it possible to adjust that screw without removing all the body plastics and gas tank again?
nitris223
TY 4 Stroke Junkie
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You might have to do it by feel. I don't think you can see it from the side. maybe with the secondary off you might be able to see it.
newbb
Extreme
looked at it today and thaT little screw is really hard to get at with gas tank on. ugh
Does that little screw adjust the idle for sure? I looked at it and the way it swings downward when throttle is pulled almost seems like it would adjust Wide open throttle. It swings forward....its not a stationary screw. I cant see it very well though so I could be wrong
Does that little screw adjust the idle for sure? I looked at it and the way it swings downward when throttle is pulled almost seems like it would adjust Wide open throttle. It swings forward....its not a stationary screw. I cant see it very well though so I could be wrong
nitris223
TY 4 Stroke Junkie
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Did you have your throttle bodies out when you changed the isc or did you leave them connected. I haven't had a close look at the throttle bodies and the parts diagram doesn't show what I think is there. Your throttle cable it gets threaded into a bracket at the top of the throttle bodies. When it goes through there does it go onto a cam type wheel . It should be quite similar to a set of rack carbs that were on the older triples. When you pull on the throttle that cam rotates to open all three butterflies in the throttle bodies. The screw in the front either adjust the idle or it synchronizes the butterflies . But there still has to be some sort of idle adjustment or the butterflies have to stop up against something inside the throttle body to keep them from completely closing. I hope you can follow what I am thinking. Like I said in a earlier post I had a high idle issue last year and it was corrected with the jam nut and cable threads where it goes into the bracket. I think there is something wrong with the adjustments on the cable to be honest. There is adjustments up near the throttle block also I think. I know you said you tried adjusting them with no change but it might be worth another look. I would have a good look where the cable connects to the throttle body also.
Try disconnecting the throttle cable from the flipper and see if it will start and idle. If it idles lower or won't stay running then it is in the cable adjustments. I think you could do this so long as the throttle lever stays closed to make contact. If it runs and idles high maybe just try loosening the jam nut on the bracket and screw the cable nut in and out.
I wish you were closer , I want to dig into this bugger and get it fixed. I know you will not want to do it but if it was mine I would pull the air box out completely and remove the gas tank again and start looking at the throttle bodies and cable operation while you are pulling the throttle.
Try disconnecting the throttle cable from the flipper and see if it will start and idle. If it idles lower or won't stay running then it is in the cable adjustments. I think you could do this so long as the throttle lever stays closed to make contact. If it runs and idles high maybe just try loosening the jam nut on the bracket and screw the cable nut in and out.
I wish you were closer , I want to dig into this bugger and get it fixed. I know you will not want to do it but if it was mine I would pull the air box out completely and remove the gas tank again and start looking at the throttle bodies and cable operation while you are pulling the throttle.
newbb
Extreme
I have the throttle cable set all the way loose and still no change in the 20 TPS reading or idle.
Im going to pop the gas tank off again and mess with the idle screw thing on the throttle bodies.
Could the sled be set up for different elevation?? causing the high idle??
The clutch does engage at 3100 rpms
Im going to pop the gas tank off again and mess with the idle screw thing on the throttle bodies.
Could the sled be set up for different elevation?? causing the high idle??
The clutch does engage at 3100 rpms
nitris223
TY 4 Stroke Junkie
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newbb said:
The tps reading may change with the idle screw. As for idle set for different elevations , no. There is a sticker on the side of the sled saying the idle to be sat at 1500 rpm +/- .
Clutch engagement is set by the primary spring and weights. Mine engages at 2900 with a OPO spring and 14.5 rollers. 3900 with a GWG spring and 15.6 rollers.
Did you try starting the sled with the cable unhooked from the lever. Unfortunately you are going to have to try all the suggestions being offered to try and rule out some of the components. Trying to diagnose a sled over the net is tuff and these 4 strokes can be a little more intimidating then 2 strokes. Lot more stuff going on . I wonder if there is any TY'er close by that would be willing to come by and give you a hand. God knows we are all over the place and could even be next door neighbors.
Hell if it wasn't for the other stuff I have to work on , I feel like tearing mine apart to see if I can simulate your problem. I am at a loss as to what more to tell you to check.
Do you have any buddies that have the same sled or are mechanics. Maybe a second set of eyes and some fresh brain power might help. You are probably getting so frustrated that you think your head is going to pop.
Do you have a local dealer or any dealer you could call that might give you some help without wanting you to drag it in.
