breaking up on full throttle

[spider525]

replaced carb20mm kienin today and new oem cluth and new zrt 1000 rpm spring ran better with old clutch ne ideas

[jerkyboy]

What main jet are you running. Next time don't make that many
changes at the same time. Change 1 thing at a time its this way
you have a idea what works & what dose'nt

[spider525]

changed it back to old oem cluch and then left the ztr spring still the same110maim

[jerkyboy]

What does the plug look like. Warm it up run it wide open
for 150' pull the kill switch and check the plug. Dark=fat
light =lean.

[spider525]

been lean and rich what do u think about float hieght or do u think it may be new spring

[Nichols Atvs]

Yes it could be the float but how could you tell ! Put every thing back to how you started out with the clutches . Tune your carb first ! Once that is done then start messing with torsion spring and rollers you have done to many things at once
. You wont know untill you start from something you allready can compair to . ALso start with a new plug . You cant read a black plug . warm up engine You need about 5 min riding time to heat up the cyl then run full throttle for 10 seconds or a good 200 feet then pull the kill teather then read plug white to lean go up black to rich go down. My stock 50 ran best with the stock torsion and 2000 clutch springs. Sounds like you have the high speed tranny gears and thay might be alittle different . let us know

[spider525]

tried every thing cant get it to stop the missing on top everthing ecept float hieght not sure of how and where it should be so frustrated the bike has great bottom and mid but sputters at wot103m in it now

[jread14]

Have you put a new plug in it? If so, what does it look like with the 103 in it? Also, where are you located at and what size bike is this on.

Have you checked your float level? If not then check that next. Take the bowl off with the gas turned off. Then turn the gas on with the carb in the upright position and with the float hanging freely. At that point you should slowly push the bowl uo. It should not shut off until the bowl is just parrallel with the rim of the carb. If it is shutting off before that then it is running out of fuel on you. There is a tab that the float hangs on that you will need to bend outwards a little to help with this.

[humboldt hills]

I have seen this so many times. Don;t get frustrated. You have to keep an open mind. Change 1 thing at a time as stated. Take notes of the changes. So many people think there is a short cut to figuring out what wrong, so they do 3 or 4 things at a time. Then frustration sets in. It may take a full day of testing to get it where it is running right. After it is right, you will have priceless notes that will save you hours of testing in the future.

In order to diagnose your issue we need much more info.
Usually if the float is not set correctly, it will want to die, not sputter. So I would say thats not it. Out of nowhere, we have had a run of bad coils. The bottom is great then the top just pops and cracks. We have also had water in the tank to create a similar effect. There are so many things it could be, process of elimination is the only way to go.