help jetting
- Thread starter mx5coco
- Start date
I think trying to jet a KX80 pipe is going to cause you a pain in the preverbial.
I do not believe that it is possible to get a 200cc displacement to accept a pipe designed for 80cc.
I very well may be wrong, there are some smart guys on here who may be able to advise you on how to do it.
I do not believe that it is possible to get a 200cc displacement to accept a pipe designed for 80cc.
I very well may be wrong, there are some smart guys on here who may be able to advise you on how to do it.
Time and patience and $$$. Like Blaaster said, there is a reason that pipe was only on an 80cc bike and not a 200cc bike. You are just going to have to take a stab at you're main, plug chop and adjust. I DEFINITELY would NOT do any other riding on that until you plug chop....or KNOW that it is so rich you teeter on fouling plugs. Or, get a new flange and the proper exhaust....that would be the best idea.
I really thing that trying to make the KX80 pipe work, would be about as hard as trying to get an elephant up a mouse's anus.
well my motor isnt in a atv frame.. its in a street legal enduro so custom is the only way, i figured a bike exhaust would be way more pain free than building my own expansion chamber, the pipe diameter is hardly different than the stock one at any point and dispite the cc difference the two motors arent far off in power output.. no advise anyone? just disagree with my exhaust choice?
With stock carb, i suggest stock pilot 32.5, and start at 270 main, may end up at 250.
plug chops will help you get that main dead on!
plug chops will help you get that main dead on!
Advice!!!!!!!! You didn't ask for someone to tell you what to run, you asked for advice. You get what you ask for, sometimes more, sometimes not specific...but you got advice. Don't be like the person who works for tips and gets pissed off because someone tells you to get educated and a better job. If you wanted us to tell you where to start with your jetting, then we would've told you what Slick did....actually Blaaster would've cut and paste his 10 step process of how to jet.
However, now that you have added more info as to what you are looking for, I still suspect the expansion chamber on the current exhaust will cause you some issues. If they are basically the same size, why did you weld it to the flange? Why didn't you just RTV it with High Temp Copper and use the spring? And you still haven't told us what carb, what size carb and what your air filter mods are....so, you want advice, research here on the forums, find out what others are running that are set up like yours and adjust to your atmospheric conditions (altitude, temp, fuel mixture). Other than that, good luck and I'm sure with a little tinkering and a few plug chops, you'll have it tuned soon enough.
There is tons of info on that here in the forum. Basically though, you warm up the bike on the old plug....stop it, swap plugs and grip and rip WOT in highest gear possible for as long as possible....kill engine, pull clutch and coast to stop. Pull plug and put in the old plug and go home. Cut threads off of plug and look at "smoke ring" around bottom of ceramic....looking for a cardboard color for safe jetting. Darker is "better" because you are richer on your AFR, light is BBBBBAAAAAAAAADDDDDDD! Too much air in the AFR, sooner or later, KaBOOM!!!
That air filter might give you fits, no distance for the air to smooth out before going thru the carb.
This is a suck it and see situation, there are too many variables to recommend even a starting point.
You say in your other thread that the welds on your exhaust are leaky.
Before you even attempt to jet the carb, make sure the intake side and exhaust are leak free.
You asked for advice, fix the air leaks, dump in the biggest jet that you think would suit that pipe and exercise the following.\
Idle adjusting.
Start with air screw 1.5 turns out.
Set idle screw so that it has some sort of idle.
Warm up motor and then set idle screw for a fast idle.
Adjust air screw either way to get the fastest idle.
Adjust air screw a little at a time leaving 10 secs to allow the motor to respond.
Re adjust idle screw for desired idle .
Then.....................
Plug chop.
Warm up motor to operating temp.
Fit new B8ES plug, ride through the gears and hold WOT in 5th or 6th gear for 10 seconds, or as long as you can safely.
Switch of the motor and pull in the clutch, roll to a stop.
Take the plug out and replace the old one for the ride home.
Carefully cut the threaded end off the plug to expose the insulator.
There should be a smoke ring of a cardboard or biscuit colour around the insulator.
If it is non existant or a very light colour, you are lean and require a larger main jet.
If it is a lot darker you are rich and may go down a size in main.
I prefer to run a little on the darker side, I may loose a little power but it is worth it for the peace of mind that I won't need a rebuild so soon.
http://www.blasterforum.com/engine-13/plug-chop-how-vid-48226/
You say in your other thread that the welds on your exhaust are leaky.
Before you even attempt to jet the carb, make sure the intake side and exhaust are leak free.
You asked for advice, fix the air leaks, dump in the biggest jet that you think would suit that pipe and exercise the following.\
Idle adjusting.
Start with air screw 1.5 turns out.
Set idle screw so that it has some sort of idle.
Warm up motor and then set idle screw for a fast idle.
Adjust air screw either way to get the fastest idle.
Adjust air screw a little at a time leaving 10 secs to allow the motor to respond.
Re adjust idle screw for desired idle .
Then.....................
Plug chop.
Warm up motor to operating temp.
Fit new B8ES plug, ride through the gears and hold WOT in 5th or 6th gear for 10 seconds, or as long as you can safely.
Switch of the motor and pull in the clutch, roll to a stop.
Take the plug out and replace the old one for the ride home.
Carefully cut the threaded end off the plug to expose the insulator.
There should be a smoke ring of a cardboard or biscuit colour around the insulator.
If it is non existant or a very light colour, you are lean and require a larger main jet.
If it is a lot darker you are rich and may go down a size in main.
I prefer to run a little on the darker side, I may loose a little power but it is worth it for the peace of mind that I won't need a rebuild so soon.
http://www.blasterforum.com/engine-13/plug-chop-how-vid-48226/
if you still have that BRICK(tors) on top of the carb, you do. its right there under the seat. kinda big hoggin thing. thats your idle screw.
Does that mean you have completely removed the unit on top of the carb or that you just disconnected it electrically? If you have electrically, you're best move would be to get a TORS removed cap and idles screw kit, not sure of the price. I might have a cap for you if you would like it, for the idle screw you drill and tap the body of the carb to accept it...wouldn't ya know it, I have an idle screw for ya also. If you would like them, PM me and we'll make some arrangements.
Idk about that exhaust?They make a dirt bike exhaust for that motor I believe.My memory is a little vague but the motor originated from an old dirtbike in the 125cc range.I cant remember I would half to google it.But any case if it were my bike I would not run that pipe.The pipe for a dt200 would be my first guess.Its made for your application.
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If you have no idle screw you should be able to set your idle by cable adjustment
The only drawback is that the throttle will increase a little when the handlebars are turned fully.
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