3/4 throttle = full throttle on 1997 XP

[SheaMolt]

my 1997 xp ran great yesterday, got it around 52 mph on glass water. Today, it fired right up, i drove it out and opened the throttle. I was going 20 mph for a second, and then i felt it kick in and it went about 40. I then drove it over to were water was glass, and most i could get was about 40. When i was driving it back home, i put the throttle at 3/4 and got 40, then put it up to full and nothing happened(No sounds whatsoever, engine sounded just like it did at 3/4). When i entered the canal it seemed like the 40 was slowly turning into 35.

I checked intake and nothing was stuck in it.
Compression as of the other day was around 150 psi

please help

tomorrow I'm going to clean the plugs (black right now)
and put more gas in it (just about at reserve.)

 

[JJinSC]

Have you checked the RAVEs? If they don't slide it acts like you are describing.

 

[SheaMolt]

The RAVE valves were just cleaned last week.

 

[scooper77515]

I agree with the RAVE sticking.

Clean them suckers up and make sure they slide up and down freely, or you get exactly what you are talking about here.

 

[JJinSC]

The RAVE valves were just cleaned last week.

Then take the plastic caps off and make sure that the bellows did not slip off of the skirt and that the bottom of the bellow is seated and sealed properly. I had one do this after reinstalling all new parts last year.

 

[SheaMolt]

i just went outside with a flashlight, and they slid up and down flawlessly. could the o-ring on it be bad? i replaced them but they were not the exactly the same size

 

[timmyboy76]

do compression check...."black plugs"

 

[SheaMolt]

Will try tomarrow. The other day i did get 150 in both cylinders, what could have happened?

 

[SheaMolt]

anyone ?

 

[timmyboy76]

smoked a piston, and/or just dumped the ring.

 

[SheaMolt]

is that common? and what if i get good compression?

 

[timmyboy76]

possible. If compression good, then I'd pull the carbs. Maybe something float'n around, and finally found the carb, or fuel selector...

 

[SheaMolt]

Well, i just rebuilt the carbs with SBT's rebuild kit. I have been needing to clean the fuel filter after every ride though.

 

[timmyboy76]

that crap in the filter,..some of it, could be in the internal filter of carb...pssible also, that your needles are leak'n/stick'n.

 

[scooper77515]

I just got back on here and noticed that you and I posted at the same time about the RAVEs, Sorry.

Cleaning the fuel filters after each ride?

Still running gray lines and they are deteriorating, maybe?

 

[SheaMolt]

When i took the carburetors off, i took a fuel line the had gas in it, and cut into it, and it looked like it just came out of factory.

 

[SheaMolt]

Alright, i just went to check compression, and got 150 PSI in the back cylinder, and 145 PSI in the front cylinder.

Also, when i got back, i realized the fuel tank was just about at the reserve tank. Could a low gas level make it run slow for 20 minutes? or would the engine just bog down and die if it ran out of gas?

 

[timmyboy76]

maybe...didnt think "these years" had limp mode, though.

 

[JJinSC]

A 97 xp will run until it is out of gas. No limping.

 

[timmyboy76]

A 97 xp will run until it is out of gas. No limping.

thought that..

 

[timmyboy76]

Had Sportster,..went thru/cleaned carbs, xcellerator pumps..etc. Ran awesome, for sh**-load of outings. Then it ran like crap. Pulled the line from xcellerator, and what you know, had this brown/stringy sh**, all throughout it, and pump...?

 

[JJinSC]

I might have to take that back. Thinking back to about 12 years ago, the only time I ever had to run on reserve. It did seem like I had to limp part the way back. How can we find the answer to this? I am curious now.

 

[SheaMolt]

Alright, if i could drive i'd probably go down and get some more gas for it, but seeing as i cant, should i just stick on reserve and see how it does? i'm afraid there might be a whole bunch of crap on the bottom of the reserve.

 

[SheaMolt]

Alright, last night i tried it and it was still only topping out at about 40. One thing i noticed was the back spark plug looked nice and brown, but the front one is looking black. Could this just be because it's not going faster at full throttle, but it's pumping more oil?