General Dirt Bike Questions

anderson750 said:
When you hold the carb upside down with the bowl off is the float all the way down or does it sit level and if you push on it lightly it goes down and springs back to its original position? There should be a spring associated with the float needle that keeps tension on it.
Click to expand...
Is the float needle the small metal piece that looks like a tiny weight hanging off the other end of the float? It fits in a small hole? I don't remember seeing a spring anywhere but I will pull my carb back out this morning and find out.
 
anderson750 said:
When you hold the carb upside down with the bowl off is the float all the way down or does it sit level and if you push on it lightly it goes down and springs back to its original position? There should be a spring associated with the float needle that keeps tension on it.
Click to expand...
If I hold the carb upside down with the bowl off the float just falls in to the carb with no spring. If I turn it the way it sits in the bike the float follows gravity and falls til it is stopped. No springing back if I push on anything and no spring in sight. I tried starting the bike forever last night and a little this morning. So the bowl should be full. When I took the bowl off today it was almost bone dry. Yes my gas was on and gas in the tank.
 
The spring mechanism is internal to the needle. If you look at the top where the tab for the float sits there is probably some type of pin in the center that is spring loaded. The picture I linked was probably not for your carb. To clarify in regards to that picture I am not talking about the long spring next to the needle.
 
I took a couple pictures for reference. The first one is a picture of my float needle? The second one is of the inside of the carb. There larger hole is where the float needle goes down in. Is there supposed to be anything else down there in that hole? Is that where the spring goes?

IMG_0799.jpgIMG_0800.jpg
 
Last edited:
Checked the pin, it springs back just fine. i rechecked the accelerator pump after I put some fuel in the bowl. Turned it twice and after that it would squirt gas every time. So that is in working order also. I got everything back together installed it all back in, got some fuel running to the carb, hit the magic button and it fired right up...................for 2 seconds!:mad:

I turned the fuel screw a little at a time to about 4 turns. Fired up finally and stayed running. Idled perfect, didn't skip a beat. Then I tried to give it a little throttle and it bogged. Tried a few more times and it would still bog. Then I eased on it for a few seconds and it revved great, but only in the mid range. If I tried to rev it in the low end it would bog. I let it idle a little longer (this is for about 2 minutes). Revved it again, it bogged so I let it idle some more but after about 4 seconds it just died. I tried restarting it for about 10 minutes to no avail.

I'm finally getting somewhere, I just don't know where. :confused:
 
Have you checked the float height setting? Your manual should describe how to measure and set it. Not sure it's your problem but it can definitely screw things up if it's off.
 
Greg said:
With it's 4 speed transmission? Not sure why you would want to try that. An EXC would MUCH better to start with.
Click to expand...

The SXF has the same problem as a CRF450R or YZ450F. Its a track bike. Can it run trails....it can but you will work riding it. You really want an EXC or XCW or put a Rekluse on it if the price is right on the SXF. Buy the right bike for how your going to ride.
 
I have my 250 xcf which I'm happy with. I had a guy offer me his Ktm for my yfz quad. That's the only reason I considered it at all. Thought it would be nice to have a 450 and 250 but if it won't have the best results then ill pass on it. I keep having plenty of trade offers. Just trying to find the right one.
 
You must log in or register to reply here.
Back
Top