engine spatter

GoldenMotor.com
R

Rusty1

New Member
Jun 12, 2012
50
0
0
U.S.A.
I have a 66/80cc Skyhawk and I'm well past my break in period . It runs beautiful during acceleration but as soon as I hit a constant speed I get engine spatter . I've done everything I can think of including spraying starting fluid around the engine to check for leaks to diagnose the problem with no success . Once in a while at W.O.T. it will smooth out and run like a bat out of **** . I absolutely love my bike and want to be able to enjoy riding it but at this point I'm afraid to take it very far for fear of doing some sort of permanent damage to it . ANYBODY HAVE ANY SUDGESTIONS ? I'm desperate !


Gotta show off a bit . its my 1st build and I'm kinda proud of it
 

Attachments

R

Rusty1

New Member
Jun 12, 2012
50
0
0
U.S.A.
I'm at 32 to 1 . I had thought that the heavy mix for the brake in period was the culprit but it hasn't changed and I've got a good chocolate milk color to my plug .
 
locell

locell

Member
Jan 16, 2010
215
0
16
mesa
hmm that was my first suspect, maybe something is vibrating loose at WOT and causing this. That can for sure happen.
 
biknut

biknut

Well-Known Member
Sep 28, 2010
6,632
411
83
Dallas
Very nice looking bike. You have a right to be proud.

Sounds like your bike has a common problem called 4 stroking. It usually happens up near top speed, most often caused by rich running.

Looks like you bike has a CNS carb. They're hard to get to work right. You'd probably be happier with a NT, or Speed carb. Buy a 66, and a 68 jet to go with it. Try the 68 first.
 
locell

locell

Member
Jan 16, 2010
215
0
16
mesa
ahh try this too - pull the top screw where your throttle cable goes into the carb. There is a barbed brass colored tube with a circlip on it. Try adjusting it up/or down see if that helps.
 
maurtis

maurtis

New Member
Dec 14, 2011
707
0
0
Kyle, TX
Uh, your motor is clearly marked 48cc, so you must be a troll!

heehee j/k...

If it was an NT carb I would say to check what slot your needle was on, but since it is a CNS carb, no idea.
 
2door

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
Start reading. > http://www.google.com/cse?cx=partne...=1407j587149j5#gsc.tab=0&gsc.q=CNS&gsc.page=1
There has been a lot written here about your carburetor. Read through some of this information and you might find an answer to your problem.

You said your engine is "well passed break in". How much is that. The little 2 strokers run better the longer you run them. One or two gallons isn't enough to get the most performance from them.
Good luck and keep us informed of your progress.
By the way, you've built a fine looking bike. Congratulations.

Tom
 
locell

locell

Member
Jan 16, 2010
215
0
16
mesa
if its 4-stroking because it is running rich, how can he lean it out? put more oil in the gas? run it with a hi-flow air filter? I thought all the carbs had those slots/circlip thing but i guess not
 
R

Rusty1

New Member
Jun 12, 2012
50
0
0
U.S.A.
Locell I just tried it . No help ! there is only 1 slot on the pin . No adjustment available . NEXT ? Lol .
 
R

Rusty1

New Member
Jun 12, 2012
50
0
0
U.S.A.
Lol maurtis . Although the law in these parts are a real pain in the butt they're quite easy to fool ! I've put at least 5 or 6 gallons threw it . It's my main source of transportation at the moment .
 
locell

locell

Member
Jan 16, 2010
215
0
16
mesa
Rusty1 said:
Locell I just tried it . No help ! there is only 1 slot on the pin . No adjustment available . NEXT ? Lol .
Click to expand...
hmm, maybe put a couple bottlecaps of oil in the tank to lean it out or run it with a hi-flow air filter. all the carbs Ive used had that cir-clip thing so I am not really sure. Are you in a high-altitude location? I know that can mess with things.
 
R

Rusty1

New Member
Jun 12, 2012
50
0
0
U.S.A.
I'm in Michigan so I wouldn't think that would be a problem . I still have the stock petcock valve on it . Is it possible I have a fuel flow problem ? One thing I forgot to mention is that after its warmed up I have a hesitation when I slow down or stop and throttle back up .
 
R

Rusty1

New Member
Jun 12, 2012
50
0
0
U.S.A.
Playing with the choke was the 1st thing I tried . It just causes it to bog and and run bad . I think I'm going to try to replace the petcock 1st and if that doesn't help it might be time for a better carb . If it is 4 stoking can it harm the motor ?
 
locell

locell

Member
Jan 16, 2010
215
0
16
mesa
hmm ya that sounds like a plan, Ive never run that type of carb before so im just grasping straws at this point.. good luck and keep us posted
 
R

Rusty1

New Member
Jun 12, 2012
50
0
0
U.S.A.
Thanks a bunch for taking the time to try to help locell . I haven't given up hope yet . It may take a while but I'll get it right sooner or later .
 
biknut

biknut

Well-Known Member
Sep 28, 2010
6,632
411
83
Dallas
locell said:
if its 4-stroking because it is running rich, how can he lean it out? put more oil in the gas? run it with a hi-flow air filter? I thought all the carbs had those slots/circlip thing but i guess not
Click to expand...
The needle only effects the mid range. This problem is on the top end. You have to change the jet for that.

I've read that some of the new CNS carbs don't have jets you can replace, or even needles you can adjust, which makes them junk. They're not jetted to run well, they're jetted to pass EPA.

None of the CNS carbs seem to be jetted right.
 
You must log in or register to reply here.
Top Bottom