Minarelli vertical stage 6 racing problem

[Downsouthdio]

Hopefully someone can give me some good info.. I feel like ive tryed everything..setup is stage 6 racing cylinder,stage 6 racing crank, yasuni c16,ct mani ,oko 19mm..thing idłes beautiful.. Compression is at 125.. Now ive tryed different heat range plugs ngk 7-9.. Different jetting combos pilot and main..different base gaskets also,, heres the thing.. Idles fine any throttle its sounds like detonation and backfires out the exhaust.. No matter what ive changed around.. This backfiring and not being able to go anywhere over 1/4 throttlle has not changed.. Any ideas guys?

[paulpauly7]

i have a similar problem but a afo5e malossi bore 120compression ported block ct 24oko tried a range of new plugs different jets i changed the stator and pick up the coil the cdi i even bolted the engine in to another bike that ran fine so i know the electrics on that one work well i change fuel i change carbs i change intakes i changed exhausts and still same problem idles great anything over 1\4 throttle and it back fires farts and * around i even took off the bbk and fitted the stock 50cc cylinder no change oh and i split the cases put in new bearings and seals and case gasket still no change *

[Downsouthdio]

Yup sounds exactly like my problem.. Idk what else to do.. Ive tryed what seems to be, everything

[paulpauly7]

baka any thoughts?

[Downsouthdio]

This kit came with a few different base gaskets.. Pretty much tryed every combo.. Just seems like its drowning in fuel.. "Fourstroking" and backfiring out the exhaust..i spent all day today trying differnt things,, no affect on it..

[kingkamehameha]

What is your needle clip set at and how do the reeds look? Did you check out our carb float needle and the sear to make sure its all clean and working properly? What kind of oil ratio are you mixing? Did you do a leak down test?

[paulpauly7]

ive changed to several different known working carbs i switched to a brand new ct intake as well l.I noticed tonight that while riding and at like 10mph farting spluttering and back fireing if i lift the cap off the sparkplug and move it away slowly it starts to clear up to almost perfect (its hard to hold it and go wot at the same time) as soon as i plug it back on bluurrrrrr backfire backfire bluurrrrr its back to being a peice off poo the spark would be jumping about a inch from the inside of the cap to the end of the spark plug.Ive changed x3 coil packs leads insulator caps and multiple new spark plugs and different gap settings


Sorry for jumping into you thread but your problem sounds the same as mine and im out of ideas

[kingkamehameha]

Did you inspect your stator to make sure the woodruff key is in straight? Sometimes during assembly the people dont get the mag on straight or the key is old. Everytime i put a block together i always use a brand new key and also a brand new drive face. How does the stator and pickup look is there any corrosion? Are your grounds all clean and tight

[Downsouthdio]

Needle for me is on the bottom clip .. The thing is with mine, nothing ive done had made a change.. From the very first start up to now after all the stuff ive done, differnt needle clips mains pilots.. Base gaskets..king no leak test..all grounds are good.. Reeds yea i checked em out looked good.. It just seems like its loading up with fuel..like super rich..fresh gas and 32:1 but that seemed to be alot of oil you could tell.. Leaned out on the oil and put a fresh tank.. Same thing..this ones testing my little bit of skills here ..

[Downsouthdio]

Anything past 1/4 throttle itS like its drowning.. N just backfires

[Red Eft Performance]

Sound like an ignition timing problem to me. Check to make sure all ignition components were installed correctly. Check the ignition timing per the manual. Try a different CDI.

[paulpauly7]

woodruff is new stator has been change for two known working ones i resoldered all connections added a couple of earths still the same cdi has been changed

dam thats a nice pipe where did you get it?

[Downsouthdio]

I thought the same thing.. Dont have a spare cdi on hand so i need to go hunt around a little.. Its frustrating.. It cant be anything else ive overlooked everything for hours and hours.. All day ..cdi im going to try that.. Different heat range plugs and all ive tryed

[kingkamehameha]

For one the needle clip shouldnt be that low i would raise it up to the middle. Do a leak down test and make sure the timing and ignition system is right

[kingkamehameha]

Did you make sure your carb is put together right?