boiling gas

[MikeB]

I have noticed that I have more power at the beginning of the trail ride. I do long steep hill climbs and steep descents. On the descents the bike stalls and I have a hard time pop starting the bike. I noticed the power loss because I can do a wheelie when I first start off but by the end of the day it has no bottom end. I was wondering if I was boiling my gas. I just read about how pro riders put heat shielding on the bottom of their gas tanks. Has anyone had any problem with this or is it that I’m just weaker at the end of the ride and can’t do a wheelie. I weigh 220 and it may just be more than my bike can handle.

Any thoughts

MIKEB

 

[JoshP]

2 Stroke? 4 Stroke? If it's a 2 smoke it may just be getting bogged down and needs to be cleared out a bit. I used to have a hard time with my KDX and it turned out to be jetted really rich and not enough air so by the end of the day it had no power at all.

 

[MikeB]

sorry for the lack of information. The bike is a two stroke. When I get to the flats I really clear it out, but with no luck.

 

[gasgasman]

Probably fuel trapped in the carb vent lines.
They have to run straight down for draining.

 

[GMP]

There is no way a GG 2-stroke will get hot enough to boil fuel in the tank. Check your float level as well as the vent lines. Split the vents, run two up/two down. Whats youur jetting? Other rich/lean symptoms? Does the bike run hot/boil over?

 

[MikeB]

Im not sure of my jetting. I had it calculated by LTR. They sent me the kit that was for my elevation. I dont know if it is running rich or lean. I would guess thats a good thing. I checked my plug and all looks good. As for the float... that may be a posibility. How would I know if it needs to be up or down more? Also tell me more about the vent lines. They all just go straight down. I have seen some people vent them to the air box. Is this what was ment?

Thanks for the help.
keep it comming

 

[iancp5]

Ok if you just fitted a jet kit blind I think the best thing is to tell us what the bike is: 125, 200, 250, 300, 450 and what the jets are; pilot, main & needle inc notch.

This is where I upset everyone. LTR seems to recommend very rich settings for some bikes. It is also possible an order got mixed up and you have the wrong kit.

 

[JoshP]

What gas to oil ratio are you running, along with the oil you are mixing with. Also what is the air screw set to, since I had a similar issue on my KDX and after jetting it wasn't perfect until I set the air screw to 2 turns out (Damn Kawa's).

 

[MikeB]

My bike is a 99 mc250. im going to check the jetting in the morning. Ill let ya know whats what.

 

[MikeB]

For the gas... I used amsoil dominator. I used it 50 to 1 ratio. Run on 91 pump gas. In Idaho that the best you get unless you get race gas. As for the air screw it is out 2 and 1/4 turns out. I belive that is what LTR recomended.

 

[MikeB]

Okay I just found my jetting information. The main jet is 172 and the slow jet is 42. The clip position I was told to set in the #3 postion (center) but I moved the needle down on notch. (leaner) The air screw as stated earlyer is about 2 or 2 1/4 out. My elevation is between 5000 to 6000 feet. I also do some dune running. I heard it was better to run it rich when your out there.

I cant think of any other information that I have.

Take a loo

 

[rockyroad]

With a 172 and needle in that position, sounds lean. If you have a 175 or 178 try one w/ needle in middle. This is assuming float is OK.

 

[FFRDave]

I do not know