Carb adjustment/ breaking in

Brotus · Nov 25, 2012

So I have been lurking in this forum since I saw someone riding a MB but have just now gotten around to posting.
I put a BGF 66 on my Wally World nel lusso and have run almost a gallon thru it. It was running ok, a little rough but I got the mixture dialed in so it will 2 stroke good thru the midrange but when it gets toward the top end it throttles itself down almost like a governor.
I was fine with this until I ran out of gas and at the last moments of starvation the engine really ripped!
This made me think it was running rich( plug looks ok, little dark) so I have been playin with the mix screw and moved the needle one setting leaner but its runnin the same.

My question is- is it too early to start adjusting? Will the post break in mix solve my problem?

Also I have experience with single cyl dirtbikes and small engines but not much 2 stroke exp.
any thoughts, suggestions??
Thanks

2door · Nov 25, 2012

They will continue to run better the more miles they accrue. You need to keep in mind that at WOT the needle isn't a factor. Fuel delivery above about 3/4 throttle is dertermined by jet orifice size. By the time you go to WOT the needle is out of the jet.
I'd give your engine some time before being too concerned. Anywhere from 2 to 300 miles is needed for complete break-in. After that you can begin to experiment with jets and other ways to increase performance.

Tom

Venice Motor Bikes · Nov 25, 2012

2door said:
They will continue to run better the more miles they accrue. You need to keep in mind that at WOT the needle isn't a factor. Fuel delivery above about 3/4 throttle is dertermined by jet orifice size. By the time you go to WOT the needle is out of the jet.
I'd give your engine some time before being too concerned. Anywhere from 2 to 300 miles is needed for complete break-in. After that you can begin to experiment with jets and other ways to increase performance.

Tom

I concur 100%! (^)

Brotus · Nov 25, 2012

Roger that, ill just just keep riding her and get a feel for the engine- it's a really strange running little guy. Then again the whole bike is doing things it's not designed to do lol. Thanks for giving me some peace

of mind for the next 300 mi!

maniac57 · Nov 27, 2012

Brotus said:
Roger that, ill just just keep riding her and get a feel for the engine- it's a really strange running little guy. Then again the whole bike is doing things it's not designed to do lol. Thanks for giving me some of mind for the next 300 mi!

Forget all your previous two-smoke experience. These little motors are unique! Just because it LOOKS like a japanese motor doesn't mean it runs like one...My Suzuki RM sneers at my MB when I park them together...and then cries when I take the MB every day instead.

Brotus · Dec 15, 2012

UPDATE. Tore down the carburetor with the intention of adjusting the float arms to stop the bogging. I got a little surprise when i opened the float bowl and the brass jet had rattled itself out and was loose in the bowl! Got it snugged in there and threw some formagasket on the manifold when installing it. BINGO runs like a little weed wacker now. however my spark plug seems to be either melting the plastic on the ignition wire or there is oil coming from the top? its torqued and seals good but theres some black fluid oozing out from under the ignition wire?!?!?! help?

maniac57 · Dec 15, 2012

Brotus said:
UPDATE. Tore down the carburetor with the intention of adjusting the float arms to stop the bogging. I got a little surprise when i opened the float bowl and the brass jet had rattled itself out and was loose in the bowl! Got it snugged in there and threw some formagasket on the manifold when installing it. BINGO runs like a little weed wacker now. however my spark plug seems to be either melting the plastic on the ignition wire or there is oil coming from the top? its torqued and seals good but theres some black fluid oozing out from under the ignition wire?!?!?! help?

Nothing a new plug won't fix. Make sure it's tight. You need a spare anyway...

Search

Carb adjustment/ breaking in

Brotus

New Member

2door

Moderator

Venice Motor Bikes

Custom Builder / Dealer/Los Angeles

Brotus

New Member

maniac57

Old, Fat, and still faster than you

Brotus

New Member

maniac57

Old, Fat, and still faster than you