Problems with fuel control

GoldenMotor.com

billragland

New Member
Aug 14, 2010
20
0
1
Springvale, ME
I purchased a Grubee kit and Micargi bicycle several months ago and have had very little good function. I have upgraded different things and brought it to a professional bike assembler but I still have problems with flooding and ignition. I have replaced all of the electrical components twice thinking that was the problem with no ignition. I have disconnected the kill switch and replaced it with an on/off switch interrupting the ignition circuit because it seemed that every time I used the kill switch, the perfectly operating motor on a ride would not restart and necessitated me walking and riding the bike too far for my disabled body to enjoy. I have replaced the carbureter with the speed carbureter available on the Spooky Tooth website. When it works with a 36 tooth sprocket it goes way too fast for my comfort and up any hill I've tried. I have left the fuel valve on for just 5 minutes and the engine fills with gasoline, which is very difficult to clean out. (Remove spark plug, carbureter, muffler and peddle for a long time with the clutch engaged.) I have done that twice now and the bike still will not start with a pullstart. When it is working, it starts with one easy pull every time and runs like a stallion. I am just getting sick of the extensive periods of time when it doesn't run. My expectation is that this will be my backup transport in case my car breaks down or my wife is away visiting relatives and I need to go get something. I would appreciate any suggestions. :-||
 
Last edited:

bairdco

a guy who makes cool bikes
Aug 18, 2009
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living the dream in southern california
your float may be sticking, or filling with fuel.

if it's sticking, it's probably the needle and seat. could be some dirt, little chunk of metal, rust, or something that's stopping it's movement. cleaning it out and inspecting it should solve that.

if the float itself is filling with fuel, you'll need another one.

the float level might be off, too. sorry, dunno offhand what it's supposed to be.

the weight of the fuel can easily overcome the pressure on the needle and seat, so make sure you turn your petcock off all the time.

as you know, a flooded engine won't start untill the flood recedes, so i doubt it's your electrics.

one more thing, if your carb is at an extreme angle, all of the above is compounded.
 

GearNut

Active Member
Aug 19, 2009
5,104
11
38
San Diego, Kaliforgnia
The float level is 21mm, as measured from the gasket surface of the carburetor body to the top edge of the float as it rests on the float lever. It is easiest to measure and adjust with the carburetor sitting upside down on a bench.
 

Kevlarr

New Member
Jul 22, 2009
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Mi
One thing to check is look at the float lever where the needle attaches to it, the two little tangs that engage the needle need to have a slight downward curve to them. If the tangs are straight they'll contact the carb body causing the needle to stay open.

Found this to be the problem with my flooding carb.
 

billragland

New Member
Aug 14, 2010
20
0
1
Springvale, ME
I was just reviewing this thread in response to my fuel problem and noticed I didn't thank everyone for their input. (I don't think I did) All of this was solved when my 2 cycle burned up due to gasahol and I went to a 4 cycle kit which solved all of those problems. The folks at EZMotorbike.com have supported their products that I received for over two years. I have still had challenges with bike mechanics, but not a bit of problem with ignition or performance, which has improved steadily throughout my use of the bike. I have probably traveled 3,000 miles up and down hills and the engine and drive system has operated flawlessly. Thanks again for all of your support for my 2 cycle 66cc.wee. destined for death initial build.

Regards,

Bill Ragland
Mainiac Motors.wee.
 

paul

Well-Known Member
Dec 23, 2007
5,547
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Kalamazoo, MI
welcome to the forum bill. great advice from the members to get your motorized bicycle running from the members, lots of good people here and we all learn from each other, please share what you learn, glad you joined us