Stumped - I picked up a 97 Ultra that was burned. Fixed all the wires and lines and crap. Had a friend come over and match the carbs up with a ball tester. Starts and runs good. Tooling around the yard is fine. Jumping on it is fine. The problem starts when I'm running a little harder and really gasing on it...Like on a straight road. Now the engine shuts down. Then I stop and start it again. Then the same thing happens. Only had it once where I could not pull the cord. Took the belt off and turn the motor by hand cause when I pulled the cord the hole sled went backwards. Just don't have any idea why the motor shuts off at a higher speed!!
This thread is also in HIGH TECH DISCUSSION FOR THE PERFORMANCE TUNER > ENGINE MODIFICATIONS/ENGINE BUILDING. Didn't seem to be getting to much action over there so I put it in this place... let's hope for some good answers!!

is your coolant topped off well?

is your coolant topped off well?[/b]
Yep..... check that befor taking off. Its funny, I can gas on it enough to raise the front end up but on the long straight away she will just die!

Sounds like it's running out of gas, either from the tank not being vented, a fuel pump problem, or maybe a kinked gas line.

Sounds like it's running out of gas, either from the tank not being vented, a fuel pump problem, or maybe a kinked gas line.[/b]
Well I will go thru and check that out... I have 5 acres. I can tool around my yard for 30 minutes or more and have no signs of any problem. That is the weird thing. But those above would not cause the motor to be hard to crank over. Sometimes that has happened. Once it has shut down??

do you have a crank or main bearing going?

do you have a crank or main bearing going?[/b]


I was thinking the same thing, there might be some oil going in, but not enough, and the high speeds might be getting a bearing to lock up.

I'm with Tifa, my first thought would be a crank bearing, but, my experieince is once they go south, it's always hard or impossible to crank the engine. Could be a mild siezure of a piston, you may may have an out of round clylinder, that when cool works ok but once the engine warms up, the piston will stick ( sieze) in the bore. Once it cools down it loosens up and you can crank it again. Either way, looks like you are loooking at a tear down. :(

Heck -- I just put it back together... I had someone tell me that maybe not enough gas getting in. That on the full , its not getting enough in there to fire and that might be a reason for it shutting down.
(NewfieBullet) was this what you ment with the gas, also?
I guess I could pick up a few gaskets and tear the top off and look at the pistons. What about electcal wiring? This sled was running good till it cought on fire. I bought it from the insurance company. There really was no wirers that were bare. Just replaced the fuel tubes and oil tubes. The sled was a friend of mine so I know how it was working before.

You don't need to replace any gaskets. You can pull off the Y-pipe and have a look at the piston skirts, Or you can pull off the head and take a look at your cylinder walls.
Now of that will tell you is you've got a crank bearing going though.
And yes, it sounded to me like it wasn't getting enough fuel for sustained wide open throttle operation.

but when you said it was hard to turm over it means something is locking up. did you prelube everything?

Stumped - I picked up a 97 Ultra that was burned. Fixed all the wires and lines and crap. Had a friend come over and match the carbs up with a ball tester. Starts and runs good. Tooling around the yard is fine. Jumping on it is fine. The problem starts when I'm running a little harder and really gasing on it...Like on a straight road. Now the engine shuts down. Then I stop and start it again. Then the same thing happens. Only had it once where I could not pull the cord. Took the belt off and turn the motor by hand cause when I pulled the cord the hole sled went backwards. Just don't have any idea why the motor shuts off at a higher speed!!
This thread is also in HIGH TECH DISCUSSION FOR THE PERFORMANCE TUNER > ENGINE MODIFICATIONS/ENGINE BUILDING. Didn't seem to be getting to much action over there so I put it in this place... let's hope for some good answers!![/b]

Just a long shot, but my 96 Ultra has a little kill switch pin in the throttle assembly which allows you to start the engine, but then shuts it off when the throttle is squeezed. Mine won't let me run at any speed, but maybe yours is just engaging at a higher throttle squeeze. Just a thought and a quick thing to check.

Good Luck.

Just a long shot, but my 96 Ultra has a little kill switch pin in the throttle assembly which allows you to start the engine, but then shuts it off when the throttle is squeezed. Mine won't let me run at any speed, but maybe yours is just engaging at a higher throttle squeeze. Just a thought and a quick thing to check.

Good Luck.[/b]

I never heard of that before but I can check into that. Just had it in the garage checking to see if its the fuel system. Need to secure the sled a little more I don't need it going thru the wall and into my living room... but that is one way to get the room redone... lol
Was gasing it over and over again but don't see any signs of lack of fuel up to the filter but nothing so far.
Thanks for the info.....

thats just the throttle safety. i wanna know what you mean by hard to turn over after it quits. im thinking definately mechanical not electrical.

Sounds like the fuel supply is somehow inadequate, could be a flow rate problem: junk in the lines, or jetting, but whatever it is, I think you're very close to toasting a piston or more. Dying at high speed and getting a "tight" engine is consistent with a lean/starving overheat problem. I guess it could also be a problem with inadequate warm-up and too much sustained load on a less than temp stable cylinders and pistons. The warm-up problem should not be related to running out of fuel though.

Is your pump OEM?

Sounds like the fuel supply is somehow inadequate, could be a flow rate problem: junk in the lines, or jetting, but whatever it is, I think you're very close to toasting a piston or more. Dying at high speed and getting a "tight" engine is consistent with a lean/starving overheat problem. I guess it could also be a problem with inadequate warm-up and too much sustained load on a less than temp stable cylinders and pistons. The warm-up problem should not be related to running out of fuel though.

Is your pump OEM?[/b]
Yes its OEM. The plugs are on the rich side. I broke down all three carbs and cleaned them (garbage tie and all). I can start it on a cold start in a few pulls. I let it warm up about 15-20 minutes before I do anything. It will stay running that hole time.

(TIFA 5 2000) == what I mean by hard to pull over is that, on a flat road I went to pull the cord and the hole sled came with. It did that twice. The third time it started.

The only thing that I havent done is drain the tank and flush that. Unless something blew thru the lines. That wouldn't be the first time. Had a piece of plastic about a 1/16 in a needle before.