Yz80 Pleas Help

[2 stroke lover]

could it be the air filter its never been cleand that i know of

[02yamahablaster]

It could be causing problems. Clean it or better yet get a new one.

[bfulton620]

dude.... like i said... mine was always breaking down... it was a pile.... the solution i finaly came to, was..... its damn near 30 years old.... and when i started to spend 6 hours of wrenching on it, for every 1 or two hours of riding time ride time, i decided to get a new bike.... for all the money i was spending in rebuilds and breaking down, and little things here and there.... i was able to get a newer bike.... that didnt give me any problems for a few years..... and ill tell you.... that feeling of being able to trust your bike, and depend on it, and know it aint breaking down, is priceless........



so what your saying.... is that it does run? like it starts, and iddles..... but when it does run, it smokes alot? and it backfires?.... and sometimes it wont even start at all? it just backfires?


sorry.... maybe im tired cause its saturday, and i had along week? but im still not clear on this?

either way... you have carburator issue's......... id say go through it again..... i did have a problem with the float on mine.... but the symtems where not the same.... i often have float issue's.... cause we have a ton of bikes at my house.... so they dont all get riden... this leaves to bikes sitting for long periods of time.... withc leads to floats going to hell.... cracking and shit like that.... this may cause them to run, and idle extremely weird... gota be carefull installing aftermarket floats that are plastic and crap....... i had also had problems where my carb got plugged up, and caused it to run odd......


i say go through the carb....

[2 stroke lover]

yeah i know i need a new bike one time i took the yz like 8miles out in the country alone and it broke down. but im 15 and this is all i got besides a cr80 and a 125m 3 wheeler but this is the most reliable thing basiccly cause the atc needs new piston and the cr80 if i could get it to get spark than that would work now i know why the dude i got it off of sold it cause its shit i tried the airfilter still didnt work went threw the carb again had the dude i got it off of set every thing cause supposly he is good at that stuff and it still is doing the same thing so im just going to waste more money on it i wish somebody would trade me for it but nobody will cause they sine what it dose. so im just going to keep doing what i can to see if it will work but im going to wait till it warms up a bit cause its cold natured and i will see what it dose from ther on.

THANKS FOR ALL THE HELP GUYS I REALLY APPRICIATED IT

[mxrobert01]

Unless you just cant part with any of them, sell 1 or 2 of your bikes and get something you are comfortable with. You are 15, riding I bike that I would think is getting pretty small for you now huh?. I am 14 with an rm85l (big wheel) with a 105cc big jug and I dont think I could deal with anything smaller. Then again I could always ride dads cr125.

[2 stroke lover]

mxrobert this is pretty big for all the 80s i have had biger than my cr80 but the cr is a pice of shit it dont get spark if i had money to get a new bike i would i almost sold my yz once but the dude wanted to see it run and it didnt start so about a hour after he left it fired right up and ran for about 2 hours the body is in good condition motor looks good but dont run good dim thinking about trying to get my 200s going but i need parts

[JordanM]

Set the ignition timing, replace filter, and once again check if the carb was assembled properly.

[chavo80]

post some pics of your bike man>i would like to see...i just clean out my carb today/new UNI filter/new NGK and some fresh new gas>>>it runs like a champ!

[amcfeek]

maybe try amd fix the cr80 for now . i wish i was closer all my freinds drag me in on these no spark issues {i mean every body}
ok what i know is these electrical issues are usually a simple fix .
the connectors thay most bikes have a re shit and corrode , expecialy from getting wet . i have gotten bikes from ppl becuase wires were off . or just plain bad connections .
clean the yz connections as well ...
1:} take each and every connection off and clean with fine sand paper and wd40 helps . run the male in and out of the female connector a few times to clean it .
next still have no spark?
2:}take a small volt meter and check for voltage as all a magneto does is generate voltage

the coil of wire that passes over a magnet will generate voltage , pr suposed to period. so if you dont have voltage comming uo from coils check resistance with the multi meter on ohms . dont kick it as the voltage will trash the meter.

you need atleast voltage on 2 wired comming up from the feilds to make spark. 1 to charge the cdi box , one to fire it with a pulse.
checl for vo;ltage by grounding the volt meter neg and checking the wires by unlugging them and pluging in the volt meter where it comes off the magneto .
ok have atleast 2 sources of voltage move up , check it by the cdi box. umplug cdi box check for voltage getting to it . and use your common sense . ok have voltage going in what about now plug it back in . got voltage comming out to coil / coil needs voltage to make spark ?plug cdi back in check voltage at coil . if got voltage check coil with ohm meter , or swap out coil to another coil for cdi ...
if you did all the above and you still cant pin point the no spark issues . donate the bike to charity as youa re not worthy ....

as far as issues with the yz i need to read this whole post ..

[amcfeek]

i doubt it but this could be a crank seal gone bad .. i doubt it . what color is the plug?if its black and oily you may need to change the crank seal not a huge job but a pain. you could try draining the crank case oil out then filing it with tranny fluid to help swell the seal up . or fill crank case with 2 stroke oil and you wont need to premix .. duh..?
ok .
also try and without turning the gas on . drip some gas into the carb and see if it kicks over and fires? or take the plug out and drip a capfull of gas into it and see if it fires. if it fires right up it maybe in the carb .
turn the gas on leav it on for a minut and then shut it off . carefully without spilling gas out of it.. pull the carb and check the float level and see how much gas is inside it. in other words . hold the carb where it wont spill the gas out after you take it out of the carb intake boot. carefylly remove the 4 bottom screws without turning it over .. if it looks beter then half full your ok .. if its too low bend the needle tab.
ok next take a small needle and put it up the main jet in the bottom of the carb's upper half . you will see a tube that comes down that the upper needle rides ina nd its a direct shot to the inside of the carbs inside this is where the gas comes up .. make shure it has no dirt blocking it . check witth a needle file for a torche or swip one of your moms sewing needles and carb cleaner the jet . slap iit back together and buy a dollar inline carb filter .. solves many carb problems as junk builds up in the gas tanks and then nothing runs ...
have fun. I hope GOD helps you get atleast one running.