Can 4T's load up on fuel? By glavey (Read 469 times)

[glavey]

When I had (and actually still do have, but never use) a nitro RC car with a .15cc 2T engine, it can and would load up on fuel if left to idle for longer than say... 15 seconds.

I think I had a similar experience yesterday with my 4T scoot at a stoplight yesterday. I must have been idling for about 30 seconds and when I went to take off, the rpms momentarily dropped a bit low for about 1/2 to 3/4 of a second. That normally never happens. Did my scoot load up on fuel while at idle?

Here are the details on my scooter; Taotao ATM50-A1 w/ 139qmb, 72cc bbk, pod-type filter, 35 idle jet, 88 main jet, needle clip one spot below top.

[cyborg]

i would think it was a delay in fuel delivery because of the carb,,,no accelerator pump ,you get the occational lag,,,then the surge of power when the needle lifts out and delivers fuel when the diaphragm pulls on the slide,,,it doesn't happen all the time just here and there randomly

[Bashan]

Yeah, I agree, it's more a function of the CV carb design rather than "loading up". In fact the CV carb helps prevent those types of things. One of the main characteristics of a CV carb is giving the right amount of fuel under a wide variety of throttle settings, it just takes a minute for the needle to adjust to the vacuum. The hesitation you get when you dump the throttle on a slide carb is actually called lean stagger. When the slide is popped open the vacuum drops precipitously and there's actually a dearth of fuel, not an excess. A CV carb will do this to a lot less of a degree. It will tend to do it after you've been sitting and idling because it takes a second for the vacuum to build back up in the slide. Blip the throttle a couple times while you're waiting and it won't do that.....Mr. Hole Shot.

[glavey]

Ah, ok. Thanks. Would gently rolling on the throttle instead of going right for WOT have any effect on this?

[Bashan]

Yep, it would stop it.