Trouble Idling When Cold

[Mr Mojorisin]

Riding bud of mine has an 06 Apex with similar kms as you , he was having idling issues and stalling as you describe. Checked, adjusted and changed out multiple components, in the end a valve adjustment was the ticket, problem solved. (the valves were out of spec).

Same story for myself. Should have adjusted the valves at 15k miles in hindsight.

 

[musselman]

That looks perfect now. Did you try playing with the idle adjustment screw on your original set of throttle bodies? Carb sync?

I adjusted the idle and synced the original throttle bodies in the fall. I had to set the idle a little high around 1800 because if i tried for closer to 1500 the idle would drop to 900 after blipping the throttle and not come back.

I'm going to pull the cam cover off this summer and check the valve clearances just to be sure. I'm still concerned about the carbon buildup on some of the valves, would running premium fuel and riding slow cause this to build up?

 

[musselman]

Just wanted to bring this thread back up, sled still isn't right so I'm going to pull the cam cover next week and measure the valve clearance. I hope I find something out of wack, otherwise I am out of options. Most of the symptoms I'm experiencing do actually point to too tight valve clearance so will be interesting to find out what's going on in there.

 

[CaptCaper]

Similar problem here ('06 RTX) that just started this year. When cold, I start the sled but as soon as it fires I need to "tip" the throttle in just sightly to keep revs at 2K to keep the motor from stumbling. After 10 to 30 seconds the motor holds it's high idle state (approx. 2000 rpm's) until the warning light goes out and all is well for the rest of the day. I'm following the advice here closely.

I had the same thing on my last Attak. I adjusted the fuel mixture in the settings to 10. can't remember plus or minus but that did the trick for me.. since then it would never stall out..stumble just a bit then hold a good idle. This is in 10 deg F or below down to 20 below .

 

[renegademan17]

Thanks musselman for all the research, my sled 07 Attak was doing the same exact thing end of last year. I am leaning at the valve adjustment from the dealer and hopefully be corrected. Post back when you get your problem resolved!

 

[musselman]

I will find out this week, hopefully tonight if they are in spec or not. I can't figure out which way to turn over the engine though in order to do the check correctly. The manual says to turn the engine clockwise from the mag side, however this turns the engine backwards? I would think the engine should be turned in the running direction which would be counter-clockwise on the mag side. Can anyone help clarify?

 

[musselman]

Where I'm at now,

 

[steveg_nh]

Holy crap! You have to remove the frame section too? Wow. Please keep posting pics. Very helpful.

 

[musselman]

Holy crap! You have to remove the frame section too? Wow. Please keep posting pics. Very helpful.

Yah I think it would be pretty tight trying to work around it.

 

[maim]

clutch rotating counter clockwise is the same as rotating the flywheel clock wise when looking at the side of the sled/motor.

 

[musselman]

But I thought you are not supposed to rotate the engine backwards? If you rotate the mag side clockwise then you will be forcing the timing chain to push against the tension because it's rotating backwards. Can someone clarify?

 

[maim]

Looking at the flywheel you need to rotate it clockwise by the flywheel to keep the tensioner tight.

If turning the engine by the primary clutch, you need to turn it counter clockwise to keep the tensioner tight.

 

[musselman]

Ok, just doesn't make sense to me since you are rotating the engine backwards. According to the procedure for the R1, the engine is rotated clockwise from the timing chain side which happens to be the clutch side on the sled. That made more sense to me so that's what I followed. If that is totally wrong please let me know.

 

[musselman]

So my initial measurements are in, looks like all the intake valves are at the minimum spec. Most of the exhaust valves are below spec with one valve at 0.004" clearance (minimum is 0.008"). Going to pull the cams and check what shims I have in there so I can order new ones. I'm going to double check the measurements once more before though just to be safe.

 

[steveg_nh]

You adjust gap by changing shims? You can't just turn a nut onto of the valve and tighten it down? That's how my friend and I did it on his diesel marine generator. Do you have to pull the cam to adjust? Or is that something else, and I'm not connecting the dots here?