hey man nice bike! i have a 92 kawasaki kx125 that as of this weekend needs rebuild. the guy i bought it from didn't know shit about it but it has always ran at 52:1 mixture. when i rebuild i plan on doing a 144cc big bore and i was wondering if you could give me a few pointers such as how to tune the carb (needle height, main jet size, air screw) and also where can i get some cheap, high quality jets? thanks
@19boykin It is a race bike. You should run premium fuel in it. Two stroke engines that have had porting and compression increases require race gas to avoid detonation. Detonation is deadly for an engine, it causes sparkplug insulators to crack, ring lands to crack, piston crowns crack, headgaskets to leak, etc.
@dirtjumpbmxer You shouldnt use that fuel in a two stroke that you have to premix fuel for. Try to use only premium petrol (91 octane or higher) since this is a racing engine...
I did it myself, the new jets are pretty cheap. You really should check the reeds and the carburetor boot for cracks and clean the carburetor and clean and re-oil the air filter, repack the silencer and then go about rejetting it. It is a high maintenance bitch like all dirbikes.
i have this same bike and year and i dont know if i should sell it..im selling it bc its so old ..you think i should sell it or fix it ..its having carburetor problemss:/
@dirtjumpbmxer If youre lucky you might get away with reusing your cylinder but if its not any good you better get it sleeved or replated. And make sure that its not running too lean, thats mostly why mine would lock up and overheat and blow head gaskets. Educate yourself and save some money. Thats what i had to do.
@dirtjumpbmxer It used to when I first got it. Someone modified it to run higher compression by shaving the head. I put on a new stock head and torqued it to 18 ft lbs of torque and always run 93 octane fuel mixed 40:1, and its fine for the past few years. You will have to get your cylinder repaired if it has blown the gasket. I advise you to look up a book by eric gorr about tuning mx bikes. It has good info about these bikes. sign up on amazon and you can read parts of the book or google it
@bmxty82 Re- jetting a two stroke involves changing the jets and needle height in the carburetor while checking the color of the spark plug between runs until the plug is tan colored and the engine is responsive and powerful.
Re- jetting a two stroke involves changing the jets and needle height in the carburetor while checking the color of the spark plug between runs until the plug is tan colored and the engine is responsive and powerful.
I have brought it back from the dead. Rebuilt, upgraded, and rejetted it. It used to lock up anytime you got it to hit the powerband. Then it would blow the headgasket on anything but premium. I had to do a lot of learning. Now it's a rock solid killer of a 125.
You need to get a few different sizes of the main jet, the big one in the center of the float bowl in the bottom of the carburetor. You can also change the pilot jet (idle to mid range) if it doesnt want to idle correctly. Typically on a two stroke bike that has had mods like exhaust, air filter, reeds, piston; you will need to lean the pilot jet(low rpm) and richen the main jet and needle (top rpm). My KX125 started with a 145 main jet and I went up to a 180 at one point, Now has 160 or 168.
hey man nice bike! i have a 92 kawasaki kx125 that as of this weekend needs rebuild. the guy i bought it from didn't know shit about it but it has always ran at 52:1 mixture. when i rebuild i plan on doing a 144cc big bore and i was wondering if you could give me a few pointers such as how to tune the carb (needle height, main jet size, air screw) and also where can i get some cheap, high quality jets? thanks
skateVA 6 months ago
i have the same bike too, ive been mixing it 32:1 with regular 87 gas. should i upgrade to the premium gas?
19boykin 10 months ago
@19boykin It is a race bike. You should run premium fuel in it. Two stroke engines that have had porting and compression increases require race gas to avoid detonation. Detonation is deadly for an engine, it causes sparkplug insulators to crack, ring lands to crack, piston crowns crack, headgaskets to leak, etc.
supra60 10 months ago
@dirtjumpbmxer You shouldnt use that fuel in a two stroke that you have to premix fuel for. Try to use only premium petrol (91 octane or higher) since this is a racing engine...
supra60 11 months ago
how much did it cost to have it rejeted. my bike keeps fouling the plugs . it all wet when i take it out.
46000rpm 11 months ago
@46000rpm
I did it myself, the new jets are pretty cheap. You really should check the reeds and the carburetor boot for cracks and clean the carburetor and clean and re-oil the air filter, repack the silencer and then go about rejetting it. It is a high maintenance bitch like all dirbikes.
supra60 11 months ago
how much did it cost to have it rejeted.
46000rpm 11 months ago
i have this same bike and year and i dont know if i should sell it..im selling it bc its so old ..you think i should sell it or fix it ..its having carburetor problemss:/
ventureskatr 11 months ago
@dirtjumpbmxer If youre lucky you might get away with reusing your cylinder but if its not any good you better get it sleeved or replated. And make sure that its not running too lean, thats mostly why mine would lock up and overheat and blow head gaskets. Educate yourself and save some money. Thats what i had to do.
supra60 1 year ago
@dirtjumpbmxer It used to when I first got it. Someone modified it to run higher compression by shaving the head. I put on a new stock head and torqued it to 18 ft lbs of torque and always run 93 octane fuel mixed 40:1, and its fine for the past few years. You will have to get your cylinder repaired if it has blown the gasket. I advise you to look up a book by eric gorr about tuning mx bikes. It has good info about these bikes. sign up on amazon and you can read parts of the book or google it
supra60 1 year ago
whats the point of rejetting what does it do
bmxty82 2 years ago
@bmxty82 Re- jetting a two stroke involves changing the jets and needle height in the carburetor while checking the color of the spark plug between runs until the plug is tan colored and the engine is responsive and powerful.
supra60 2 years ago
@bmxty82 Also running your engine too lean can cause it to not get enough lubrication and seize.
robertgisthebest 1 year ago
@robertgisthebest ya..been der done dat
bmxty82 1 year ago
Nice bike! Got one my self, hoping to start it up today. Only problem with mine is that the second gear don't work :(
HyPaH01 2 years ago
whats re jet mean
2626zac 2 years ago
Re- jetting a two stroke involves changing the jets and needle height in the carburetor while checking the color of the spark plug between runs until the plug is tan colored and the engine is responsive and powerful.
supra60 2 years ago
thats a nice bike man, i got a ktm 125 sx. yours is really nice for a 91. five stars man
worldskater31 2 years ago
I have brought it back from the dead. Rebuilt, upgraded, and rejetted it. It used to lock up anytime you got it to hit the powerband. Then it would blow the headgasket on anything but premium. I had to do a lot of learning. Now it's a rock solid killer of a 125.
supra60 2 years ago
when rejetting a dirt bike do i need to buy anything?
dat504rob 1 year ago
You need to get a few different sizes of the main jet, the big one in the center of the float bowl in the bottom of the carburetor. You can also change the pilot jet (idle to mid range) if it doesnt want to idle correctly. Typically on a two stroke bike that has had mods like exhaust, air filter, reeds, piston; you will need to lean the pilot jet(low rpm) and richen the main jet and needle (top rpm). My KX125 started with a 145 main jet and I went up to a 180 at one point, Now has 160 or 168.
supra60 1 year ago
thats the shit man thats cool as fuk
badboy81791 2 years ago