attex superchief 500 troubleshooting help please

[mototrix36]

Just got this 72 attex superchief. Ran rough and wouldn't idle when I got it, tuned it up after that it ran great just like I would think it should but only lasted for 2 days with roughly 2hrs run time and than it started bogging, not idling, would require excessive choking (sometimes) it also seemed like it would run 10x better when first started up but only last a couple minutes of riding and the problems would only arise or worsen once the engine fully warmed up. Since then I've not been able to get it running right. Currently trying to solve some sort of fuel /fuel pulse pump issue. Currently not getting any fuel to the carb even with a brand new exact replacement pump. The compression in both cylinders is 125ps(supposed to be about 147psi at my elevation) with engine cold although I noticed one cylinder is getting a lot more fuel than the other. I'm guessing the reeds are pretty shot and probably falling apart and causing that but first I need to get fuel back to the carb to get her running. Tomorrow I am going to replace all the fuel lines with new proper fuel line and filter with fingers crossed that will solve the no fuel problem. Otherwise I'm already starting to dread the infamous leaky crank seals. I plan on testing that by spraying a little ether around each side of the crankcase to see if the idle surges. This motor is fun and pretty fast but I've definitely come to realize how difficult it is to find any parts or information on this chaparral g50b motor.

Any insight to these problems or references that may help out would be really appreciated.

[BrettandCheyenne]

They can be very finicky but the fun out weighs the issues. Sounds like the same problem I had with my super chief. Ended up being a piece of dirt getting sucked up in the float bowl of the carb. Would sit over night and settle, after a bit of riding it would clog the jet. Was old debris in the line even tho the tank was cleaned. I do believe the pulse line length from pump to crank case plays a part in how well it pulls aswell. Could be mistaken on that but maybe shorter the better.. Also played around with the carb slide by raising the needle on the throttle assembly. Sounds like she's starving for fuel running the choke. Make sure your exhaust is tight no leaks and good air filter aswell. Not sure what fuel mix ratio your running but also may be too lean or too rich of a mix. Hope it's something simple... Good luck and let us know!

[johnedwardketch]

all above said by youu and the other guyy is correct but also try to open up the little breather hole in the fuel cape if that gets slightly clogged it will dirupt the integrity of the entire fuel flow from the tank it very small but you be surprised the diffrence at times??? that solution will make it has to breath air just like when you pour oil outta of a oil can...you got to have a back side air port for flow

[johnedwardketch]

also try the mixture jets there crucial for ideling one is one and a half turns vs the other at 3/4 of a turn

[Toys4Me]

Do a compression check after the engine is warmed up. I had a JLO that would run great until it warmed up and turned out to be piston slop.