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FULL EXHAUST?!

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is their any risk riding a four stroke (kx250f) without jetting the carb after putting a full exhaust on. I just road it around the block it is serious fast but it pops a little bit on decel nothing to major I know it should be jetted and I'm gonna I just wanna ride this weekend really bad i was wondering if it could cause damage to the motor I just bought a brad new one offline. Also the head pipe did get hot on the first start up but I didn't notice it to much this time. It melted a carb hose yesterday

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yes rejet it. if it's lean popping that means its not getting enough fuel it's going to burn hotter and heat in this scenario is bad. most exhaust sites have a data table for what size jets you should use with their exhausts.

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Yea i agree, rejet. It only takes a few minutes and if nothing else go up two jet sizes until you can jet properly if you have to ride. Better to be a little rich then a little lean

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I ordered a jet kit it's gonna take 3 days to get here it's a moose performance stage 1. Any word on if that's any good or not?

Yz125

Kx250f

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yes rejet it. if it's lean popping that means its not getting enough fuel it's going to burn hotter and heat in this scenario is bad. most exhaust sites have a data table for what size jets you should use with their exhausts.

Not jacking the thread, just a quick question. So, decel popping means it's lean? I jetted in colder temps, but my plugs have been looking fine, and the bike is running great, but every once in a while I will get a little popping on high rpm decel (2 stroke). I think my needle and main are fine, but pretty sure my pilot could be lean from my last setting. I know it is lean per the KTM chart, but that chart runs too rich anyway. Should I change the pilot, even if the plug and everything else looks right? I would rather be a little rich than too lean

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Yea that means it's lean and with a 2 smoker I would highly recommend running a little rich then lean it's either you foul plugs and pay 3$ every other week or you blow top ends and cranks and pay 300-400$ to fix it.

Yz125

Kx250f

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Yea that means it's lean and with a 2 smoker I would highly recommend running a little rich then lean it's either you foul plugs and pay 3$ every other week or you blow top ends and cranks and pay 300-400$ to fix it.

Yz125

Kx250f

Or you jet it right and ride the hell out of it. I have a season and a half on my plug

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Not jacking the thread, just a quick question. So, decel popping means it's lean? I jetted in colder temps, but my plugs have been looking fine, and the bike is running great, but every once in a while I will get a little popping on high rpm decel (2 stroke). I think my needle and main are fine, but pretty sure my pilot could be lean from my last setting. I know it is lean per the KTM chart, but that chart runs too rich anyway. Should I change the pilot, even if the plug and everything else looks right? I would rather be a little rich than too lean

both are the same thing, what you're hearing when it's rich however is the unspent fuel exploding.

the best way to go at determining which of the two it is is knowing what you've done to the bike, anything that adds more air flow etc richer. get what im saying? take the carb check your float level as per the manual and check your jetting out, check the reeds as well, could also cause a rich condition. set it to manual specs, and go up or down in sizes from there :thumbsup:  any other questions pm me

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Yea if you jet it right best case scenario I was just referring to him saying he wants it to run more rich. Ps ya jacked my post

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fatimals, there is a flat head screw on the bottom of the carb right before the intake to the motor, turn it out a half turn (more fuel) and you will probably have no deaccel pop. Also check for exhaust leaks they will cause popping also, make sure you got and copper rings and such installed when you swapped it.

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I'm getting it jetted this week and getting a new exhaust flange for it too I just wanna ride it tomorrow would it be safe to do so with a full exhaust and it not being jetted. The head pipe gets hot but it's not to bad I've seen them glow bright red it's just turned a shade of blue from riding it out back. Thing runs nice good throttle response I can't imagine how it's gonna be once it's jetted correctly

Yz125

Kx250f

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