250 RoketaSlowly loses speed after 5min run, then runs again By gatordawg (Read 433 times)

[gatordawg]

My '08 Roketa 250 clone runs really fine up to 50mph or so until I get about 3-4mi from the house and it slowly starts to lose speed, sorta slowly bogs down. It didn't completely stall and still idled fine as I started to panic about how I'll get it home but then after a min or two will then go another mile or so and repeat the process. Seems like it's starving for fuel at hwy speeds so maybe a fuel pump starting to fail?

Is there a link with a few pics to replacing the OEM fuel pump or diaphragm and where to get parts? Any other thoughts on what it may be?

There are no other symptoms, avg engine temps, no odd noises.

Thanks in advance for your help.

Mike

[atlfotos]

Have you ever had the valbs done?

[cyborg]

Check the fuel tank venting ,,,run it till it starts to act up then pull over quickly and crack the tank cap,,,if you hear air sucking in the venting may be partially blocked,,,or what you said the pump may have enough life at idle to fill the carb bowl then when riding under throttle it's not working well enough to "keep up"