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1995 rmx 250 wont start

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Hello I just picked up a 1995 RMX 250 for $500 its pretty nice and has a dual sport kit on it. I can not start this thing. I have spark and my compression tester reads 250 psi... I thought that was kinda high so I got the numbers off the piston cause i thought maybe high comp piston but it just a reg std bore piston from Wiseco. anyway I have Spark comp and I belive fuel as the plug gets wet. I have not tried to push start it yet. The guy I bought it from told me that it used to cut out on him and then he chaged the plug from a b8ev to a b8es and then he couldnt get it started at all. I do not have a manual as i just picked it up tonight. I really need a downloadable one so if anyone has one or knows where I could get one please let me know. I also noticed that the piston is for a 96 and up rmx Im guessing the motor is different but since i dont have a manual I am just guessing if anyone could shed any light at all on how I can find out more about this bike please let me know. I have the title and its a 95 but thats just the frame

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I had my wife pull me with the truck and it took about 2 minutes for it to start I got it started and it sounds good smoke alot at first. I drained the trans oil just to rule out a bad crank seal but it still does the same thing. Heres the prob if i keep it revved it will stay running if it runs too close to idle for too long it just dies and then I have to pull it again to start it. Could this be a prob of a too big starter jet? I will have to check whats in there. There was a 180 main jet i put a 155 in there just to rule out too rich.

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I had my wife pull me with the truck and it took about 2 minutes for it to start I got it started and it sounds good smoke alot at first. I drained the trans oil just to rule out a bad crank seal but it still does the same thing. Heres the prob if i keep it revved it will stay running if it runs too close to idle for too long it just dies and then I have to pull it again to start it. Could this be a prob of a too big starter jet? I will have to check whats in there. There was a 180 main jet i put a 155 in there just to rule out too rich.

First step is disassemble and clean the carb. Once youve thoroughly cleaned it mark down your pilot jet and main jet and needle clip position. should be ~60 pilot and 150 main if it has the stock pipe, reassemble and set your air screw to 1.5 turns out. Turning the screw in richens it, out leans it. and if it still dies on idle drop your pilot a size and try again

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hey fire, im going to be following your thread closily as iam about to pick up the same bike back here in the PNW. im hopefully picking up around the first of the year. how bout posting some pics of it?? hears a pic of the one looking in getting.

T

rmx2501.jpg

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ok cool i will post some pics either later tonight or tomorrow. I keep posting all my findings as i go even if I dont get any help lol. I will def figure it out as im not new any of it but I tend to overlook some small stuff here and there

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well after a few beers i decieded to go back out and tear the carb down and see what slow jet was in there. I had a 58 slow jet and according to the rm 250 service manual the highest rich slowjet you should have is a 60 so I have a brand new 40 laying around im gonna put that in tomorrow and see what happens

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well after a few beers i decieded to go back out and tear the carb down and see what slow jet was in there. I had a 58 slow jet and according to the rm 250 service manual the highest rich slowjet you should have is a 60 so I have a brand new 40 laying around im gonna put that in tomorrow and see what happens
58 to 40 is a HUGE jump.

what he said.. thats a NO NO

try going out and getting a 52 and a 55 and see if that does anything for ya

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Hello I just picked up a 1995 RMX 250 for $500 its pretty nice and has a dual sport kit on it. I can not start this thing. I have spark and my compression tester reads 250 psi... I thought that was kinda high so I got the numbers off the piston cause i thought maybe high comp piston but it just a reg std bore piston from Wiseco. anyway I have Spark comp and I belive fuel as the plug gets wet. I have not tried to push start it yet. The guy I bought it from told me that it used to cut out on him and then he chaged the plug from a b8ev to a b8es and then he couldnt get it started at all. I do not have a manual as i just picked it up tonight. I really need a downloadable one so if anyone has one or knows where I could get one please let me know. I also noticed that the piston is for a 96 and up rmx Im guessing the motor is different but since i dont have a manual I am just guessing if anyone could shed any light at all on how I can find out more about this bike please let me know. I have the title and its a 95 but thats just the frame

guys, isnt this awful high compression? 250psi? im not sure of the correct psi value but i think it should be 180-210psi. look at pulling ur powervalve, ive heard about the rmx having issues withem, mainly cracking and or breaking.

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Merry Christmas!

Well Yes I know 40 is a huge jump. I just wanted to see if that would help with starting it. I forgot to mention that I also took the carb off and this was after I drained the trans fluid I put the spark plug in and is still seemed to get the plug wet even after there was no carb there.I probably kicked it about 50 times I pulled the plug checked it and was wet cleaned it put it back in and kicked some more... wet plug... I was thinking bad clutch side crank seal. Guess I need to invest in a leak down tester. Im gonna see about the power valve and clean that up first. Also if you look at argclh6670's rmx his clutch side of the engine looks totally different. I think this is a year change but I am not familiar with these bikes at all does anyone else see the difference. looks like the clutch lever is different all the way to the front part of the lower end. I also thought 250 psi was way high hence the blister on my foot from all the kicking lol

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Ok i think i have found out what I am dealing with here are some of the numbers from the engine

Case: J115-104708 this seems to be a 96-2000 RM 250 bottom end

Head: 37E1 this seems to be 96-2000 RM 250

Flywheel: FP8192 Also 96-2000 RM250 I guess I just have a 1995 RMX Frame

All this info came from OEM Cycles website so now at least I have the correct Service manual for the engine I guess the next step is to find out if the electronics are for the rm will post back Im gonna check the CDI and coil and see whats up

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Ok update i know its christmas but my wife is working so im still workin on the bike. Im done for now I got it running. It turns out the stator that was in it was bad i swapped it out with the stock one and it fired right up but...... I have a new problem. The smoke is absolutely way too much gas is mixed with amsoil 32:1 I know it will create smoke but this is ridiculous i got on the throttle and it would spit spooge out the back and even left a small puddle at the exhaust tip. I put my hand behind the exhaust to catch the smoke and it left this sticky oily stuff on my glove.. Help please...

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Ok update i know its christmas but my wife is working so im still workin on the bike. Im done for now I got it running. It turns out the stator that was in it was bad i swapped it out with the stock one and it fired right up but...... I have a new problem. The smoke is absolutely way too much gas is mixed with amsoil 32:1 I know it will create smoke but this is ridiculous i got on the throttle and it would spit spooge out the back and even left a small puddle at the exhaust tip. I put my hand behind the exhaust to catch the smoke and it left this sticky oily stuff on my glove.. Help please...

well since you have a 96-00 RM250 engine, take a look at the carb and see if it says PJ28 on it. if it does you have a 96 RM250 engine. I ahve a service manual for 986-02 RM250's around here somewhere... stock pilot is 58 i believe and the PJ carb run is a little sketchy... its idle setting is on the choke so it doesn't stay put when you want it to. I think on the bike i had i was running 52/172. but you could have a bad crank seal pulling oil into the cylinder. and 250 PSI is way too high, do you have a hi-comp piston or shaved head or something?

Edit: Holy crap! :bonk: after looking at it Yes the IS indeed a 96-00 engine. Please find out what carb is on the bike, and ill try to help you jet the bike after you find out what is causing the 250PSI problem...

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Carb Specs PJ29e2 1f#

Main is 180

Slow is 58

I have a pdf manual but it looks like it form the newer rm's 2001 and on so that wont help me much.

I have no idea if the head is shaved I do have another head though how could I tell if it was shaved?

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Carb Specs PJ29e2 1f#

Main is 180

Slow is 58

I have a pdf manual but it looks like it form the newer rm's 2001 and on so that wont help me much.

I have no idea if the head is shaved I do have another head though how could I tell if it was shaved?

well.. its a PJ.. thats a start and its 38mm so it looks like its a 96 engine completely. so thats good. The pilot seems big, but the main is huge... stock is 172 so that may be your prob, also check your needle designation and clip position. As for the head, pop it off and see if your piston is striking it. I talked to a friend and he said even if it was a high comp piston or shaved head at 250PSI it would be(or very nearly) striking the head. So if its not hitting the head, you have deeper problems :bonk:. I'd verify it has a base gasket, and both of the rings under the cylinder head. If you have any specific questions and wanna see the pages from the book I can take pics or scan them and post them for you.

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ok cool thanks for the help The clip position is on the 3 from top and I think I will change the main jet first it does have a full exhaust i have a new 172 here so ill try that and see if that helps and if it doesnt i will replace the clutch side crank seal and take it from there because i figure its easier than tearing the cylinder off it is supposed to be freshly rebuilt and I believe it as there were no carbon deposits at all on the piston head it looked brand new im not sure what it looks like now but ill check tomorrow night after work. Oh and there is a base gasket but it doesnt look like it has a head gasket I think you should be able to see the head gasket right? I have one in the box o parts i got with the bike.

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ok cool thanks for the help The clip position is on the 3 from top and I think I will change the main jet first it does have a full exhaust i have a new 172 here so ill try that and see if that helps and if it doesnt i will replace the clutch side crank seal and take it from there because i figure its easier than tearing the cylinder off it is supposed to be freshly rebuilt and I believe it as there were no carbon deposits at all on the piston head it looked brand new im not sure what it looks like now but ill check tomorrow night after work. Oh and there is a base gasket but it doesnt look like it has a head gasket I think you should be able to see the head gasket right? I have one in the box o parts i got with the bike.

no, 96 RM 250 uses rubber rings for a gasket theres an inner and outer on each side of the water holes in the cylinder and head. i saw that pipe... It's definitely a frankenpipe. Some strange combo of a 96-00 pipe and a 95 pipe.. that was honestly the worst way to fab up a pipe.. but whatever. That might cause you jetting horrors by itself. you should probably talk to someone else about that super high compression, and taking the head off is really easy, just gotta re-torque the bolts when you put it back on.

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Yea taking the head off isnt a big deal I have rebuilt a couple two stroke myself and 4 strokes but I get kinda lost when dealing with something like this cause someone already did the work and i have no idea what they did or why. But thanks for your help man and Merry Christmas!

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Yea taking the head off isnt a big deal I have rebuilt a couple two stroke myself and 4 strokes but I get kinda lost when dealing with something like this cause someone already did the work and i have no idea what they did or why. But thanks for your help man and Merry Christmas!

Merry christmas to you too, I hope you don't run into anymore trouble with this thing. That is an awesome engine and you will love it :bonk:

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