Engine Trouble 80cc cutting out at higher rpms HELP

[scorpion1]

These will work?

 

[Street Ryderz]

These will work?

You may want to try a #68 #67 #66 rather than jumping 5 at a time.

 

[gary55]

Ugh............... now I'm into jetting. I cant really find any jets under dellorto clone. Anyone have a link and the size range i may need?

Like Ryderz says, the 65 will probably be to small. The #s he is suggesting are probably closer to what you need. Scorpion's right on the 5mm. Sickbikeparts sells them and are dellorto jets. The ones on eBay are often mis-sized.

 

[crassius]

still thinking that fixing the float on the carb that worked is a good idea

 

[gary55]

So reply # 7 you let it set for several months. Then you started it and it ran like s**t. Ok gummed up carb. Then you changed the carb and it still still ran like s**t. Dellortos run rich. Then you see a leaky float in the original carb. Clean the original nt carb, get a new float and your back to where it was when it was running good.

 

[Jroge1523]

I had the same problem then 2 weeks later my magneto died got a new havent that problem since you might have a weak spark or carberator jet has became loose

 

[scorpion1]

Rejetted to a 68, no help, new NGK plug tried at 3 different gaps, no help, new "performance" ignition, no help, i guess magneto check next, also will pull the head, no leaks btw. Lastly may be an offset Woodruff key to retard.

 

[scorpion1]

Rejetted to 66. no help.

I then RETARDED the timing by reducing the width of the woodruff key by almost half the width..............ran WORSE!!!! Wth???

IS THE TIMING SUPPOSED TO BE ADVANCED FOR BETTER TOP END??? *I'm reading both ways on the internet????????

I'm about to give up

 

[crassius]

dunno, stock motors seem to work well for me when I don't screw around with them - but, if you've already changed the key, then why not turn it around to advanced and see what it does?

 

[scorpion1]

dunno, stock motors seem to work well for me when I don't screw around with them - but, if you've already changed the key, then why not turn it around to advanced and see what it does?

Yep, my thoughts exactly. Its just so odd, and frustrating. I read in several places that a 2 stroke wants advanced timing at high rpms and a 4 stroke wants retarded. Too much info out there to know what is right.