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92 RM125 Issue(s)

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Hey everyone! It's been awhile since i've been on the site because i haven't had a bike. But i recently picked up this rm with no spark. I was told from the owner that it was the stator, did some testing, found it was the stator, and replaced it. No more problems. I cleaned the carb, put in a new air filter and a new plug and I was ready to test it out. 

It started up fine and seemed to idle fine. I let it warm up and put it into gear to take off and it felt soooo doggy. There was no power in 1st, 2nd, and most 3rd. The other gears are hold on for life (lol). When I got back from my small rip, I let the bike sit for a bit idling and noticed the rpm's dropped a lot, but didn't die. Flick the throttle and it goes up again, then goes back down. Does the same thing now when you're riding it and pull the clutch in or hit the brakes with the clutch in.

I noticed it has a Pro Circuit pipe on it thats stamped 92 RM with 4 digits after that. That made me wonder if it had the correct jets in it. I checked out Por Circuit's site for the specs and it called for:

330 main (STD)
50 pilot (STD)
Needle STD
Pos 2nd <--- what's this mean
Screw 1.5

I tore the carb apart to find it had a 310 main. Replaced it with the 330 and reset the air screw to 1.5. When i fired it up it had the same problem. the power may be a little better, but the idle is horrrrible. I'm unable to set the idle. And I cannot make the bike run different by adjusting the air screw away from stock. 

My compression is 105-110 wet dry warm or cold. I've been told by many enthusiast and shops that that compression is alright or acceptable. The plug after more than 15 minutes of runtime looks like a gray color. like its new, but is dirty. Hard to explain. (Super lean maybe?) I took the throttle needle out and put it on the richest setting. And when you know it, still runs horrible.

This is my second time typing this because when I went to post it, it said i wasn't signed in and deleted all of what i typed (damn). 

I do not have a manual for the bike, so any input from the guys and gals on here would be great. Thanks everyone!!

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Hey everyone! It's been awhile since i've been on the site because i haven't had a bike. But i recently picked up this rm with no spark. I was told from the owner that it was the stator, did some testing, found it was the stator, and replaced it. No more problems. I cleaned the carb, put in a new air filter and a new plug and I was ready to test it out.

It started up fine and seemed to idle fine. I let it warm up and put it into gear to take off and it felt soooo doggy. There was no power in 1st, 2nd, and most 3rd. The other gears are hold on for life (lol). When I got back from my small rip, I let the bike sit for a bit idling and noticed the rpm's dropped a lot, but didn't die. Flick the throttle and it goes up again, then goes back down. Does the same thing now when you're riding it and pull the clutch in or hit the brakes with the clutch in.

I noticed it has a Pro Circuit pipe on it thats stamped 92 RM with 4 digits after that. That made me wonder if it had the correct jets in it. I checked out Por Circuit's site for the specs and it called for:

330 main (STD)

50 pilot (STD)

Needle STD

Pos 2nd <--- what's this mean

Screw 1.5

I tore the carb apart to find it had a 310 main. Replaced it with the 330 and reset the air screw to 1.5. When i fired it up it had the same problem. the power may be a little better, but the idle is horrrrible. I'm unable to set the idle. And I cannot make the bike run different by adjusting the air screw away from stock.

My compression is 105-110 wet dry warm or cold. I've been told by many enthusiast and shops that that compression is alright or acceptable. The plug after more than 15 minutes of runtime looks like a gray color. like its new, but is dirty. Hard to explain. (Super lean maybe?) I took the throttle needle out and put it on the richest setting. And when you know it, still runs horrible.

This is my second time typing this because when I went to post it, it said i wasn't signed in and deleted all of what i typed (damn).

I do not have a manual for the bike, so any input from the guys and gals on here would be great. Thanks everyone!!

The thing about the "pos 2nd" is talking about putting the carb's needle on the second clip.

Post a pic of the plug so we can see what you're talking about please

About what rpm is your super low idle?

What do you mean by doggy? Do you mean it has a bog? Because a bog usually indicates the bike is running lean.

Is there loads of smoke coming from the exhaust? Like more than normal?

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The thing about the "pos 2nd" is talking about putting the carb's needle on the second clip.

Post a pic of the plug so we can see what you're talking about please

About what rpm is your super low idle?

What do you mean by doggy? Do you mean it has a bog? Because a bog usually indicates the bike is running lean.

Is there loads of smoke coming from the exhaust? Like more than normal?

Awesome thanks for a reply!! The Pos 2nd... that be second clip from the top I assume.

And if I were to judge the low rpm idle, I would say 500-600rpms maybe. Now when i mean boggy, I mean i could lay on the throttle and barely move. It "four strokes" for lack of better terms. Stutters real bad and acts like it doesn't get on the pipe at all. Loads of smoke? Oh yes, especially when it was warming up. And I did notice a good smoke trail behind me when I was riding it.

I can't get a picture of the plug (a sin, I know) because the plug literally went bad and I replaced it with an old on. I tried to clean the one that went bad with carb clean and a lighter, so naturally it burnt it. But imagine a new plug in a motor that was running kind of lean but burning coolant. Showed signs of burn, but was clean due to burning coolant. I dont know if that helps..

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Awesome thanks for a reply!! The Pos 2nd... that be second clip from the top I assume.

And if I were to judge the low rpm idle, I would say 500-600rpms maybe. Now when i mean boggy, I mean i could lay on the throttle and barely move. It "four strokes" for lack of better terms. Stutters real bad and acts like it doesn't get on the pipe at all. Loads of smoke? Oh yes, especially when it was warming up. And I did notice a good smoke trail behind me when I was riding it.

I can't get a picture of the plug (a sin, I know) because the plug literally went bad and I replaced it with an old on. I tried to clean the one that went bad with carb clean and a lighter, so naturally it burnt it. But imagine a new plug in a motor that was running kind of lean but burning coolant. Showed signs of burn, but was clean due to burning coolant. I dont know if that helps..

I think what you are describing is severely rich, not lean. Does it make a blubbering sound when you try to go? Lots of smoke could either mean a crank seal or just severely rich running condition and because you thought it was lean you adjusted it the wrong way..

Edited by M3NT4L5

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I think what you are describing is severely rich, not lean. Does it make a blubbering sound when you try to go? Lots of smoke could either mean a crank seal or just severely rich running condition and because you thought it was lean you adjusted it the wrong way..

That makes sense. Yeah it does make a blubbering noise when I try to go, like i have to give it a lot of throttle when I let the clutch out for it to not die. So I should adjust the throttle needle clip, and see from there? Would float height have an effect on that? Because right now its perfectly level. It's a Mikuni TM d-slide. How would I go about seeing if a crank seal is bad? And if it turns out to be bad, would my only option to fix it be to tear the whole motor down just to do the crank seal(s)? 

Again, thank you so much for your help.

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That makes sense. Yeah it does make a blubbering noise when I try to go, like i have to give it a lot of throttle when I let the clutch out for it to not die. So I should adjust the throttle needle clip, and see from there? Would float height have an effect on that? Because right now its perfectly level. It's a Mikuni TM d-slide. How would I go about seeing if a crank seal is bad? And if it turns out to be bad, would my only option to fix it be to tear the whole motor down just to do the crank seal(s)?

Again, thank you so much for your help.

If you're burning coolant you need a head gasket, also check you head for warpage when it is off.

How many turns out is your carb's air screw?

I don't know the specifics about the RM but you may just be able to replace the crank deal without splitting the case. You can do that on the cr's anyways.

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Currently it's at 1.5 turns. And I don't think it's biting coolant, I used that for an example to describe the plug.

When I have the stator off, I saw the crank seal there, it wasn't wet so I assumed it was okay. And didn't look easily replaceable. But I haven't looked at the other side yet. Will do that tomorrow and check back in. Thank you!!

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I see you mentioned loads of smoke, just wondering what colour the smoke was? If it was white and heavy it's more than likely burning coolant. I've had this problem or at least something similar. Sometimes you can look in the rad at the coolant and see debris or oily sludge up near or around the cap. It's an indicator that the combustion chamber is leaking into the water jacket or vise verse.

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Also a way to check if your crank seal is indeed bad is to check how full it is on trans oil compared to how much you put in. Also of the smoke is blue it points to a crank seal.

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Also a way to check if your crank seal is indeed bad is to check how full it is on trans oil compared to how much you put in. Also of the smoke is blue it points to a crank seal.

I'll have to run it again tomorrow and pay attention to the smoke it makes. But if my memory is correct, it was blue, will have to verify. 

I see you mentioned loads of smoke, just wondering what colour the smoke was? If it was white and heavy it's more than likely burning coolant. I've had this problem or at least something similar. Sometimes you can look in the rad at the coolant and see debris or oily sludge up near or around the cap. It's an indicator that the combustion chamber is leaking into the water jacket or vise verse.

I don't really think it was burning coolant, it didn't smell sweet. That smell sets off a "natural" alarm in my head. My snowmobile did it all the time and I knew it was burning it. And trucks at my work do it too (haha). But ill take a look at the rad cap to play the fact. 

When I bought it I did take a look into the rad, looked nice and green. But I wasn't told when the last time it was ran. 

Thank you to you two for your replies, it sure helps a lot! Keep it coming

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Alright i'm trying to upload a video of the smoke that comes out of the bike when its warm. I also meant to get a video of the low idle, but of course, i took a picture instead of a video for that one ha. Hope this determines something... 

I also moved the needle clip to the second position, ran the bike to no change in issue. And i took a look into the rad, it was pretttty clean with little black flakes floating here and there. I think that's normal, like if its paint from the rad or something. No idea ha. The cap itself is also clean. 

When i turned off the bike, I stuck my nose into the muffler to smell for sweetness. Beside the awesome smell of premix, I don't think I could smell any signs of burning coolant. But I should get a second or third nose to give me an opinion.

Hope this helps!!


Edit>>>> I guess it won't let me upload a raw video... i'll post it to youtube and set the link up here.

Edited by braaptastic

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^^ Here's one of the smoke, hope you can tell what kind of smoke it is.


^^ And here's the idle drop video ( Watch it all)

Yes, I know the idle is high haha.

Hope these two videos help!!

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Has your level of trans oil dropped at all since you last filled it up?

I've only owned the bike for a max of a month. I haven't changed the gear oil in it yet. Is there a way to check the level without draining it?

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I've only owned the bike for a max of a month. I haven't changed the gear oil in it yet. Is there a way to check the level without draining it?

Nope you gotta drain it and measure how much comes out, you should change oil in a bike when you first get it anyways. Also that idle doesn't sound especially low to me actually kinda high but I'm not exactly in a place to hear it very well

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Nope you gotta drain it and measure how much comes out, you should change oil in a bike when you first get it anyways. Also that idle doesn't sound especially low to me actually kinda high but I'm not exactly in a place to hear it very well

Gotchya. I'll change the oil and measure. In the idle video, you have to go to like the last 7 seconds of it ( when you get a chance) to hear the idle drop. Sounds like it goes from 1,600rpm to 600rpm from what I can tell.

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Gotchya. I'll change the oil and measure. In the idle video, you have to go to like the last 7 seconds of it ( when you get a chance) to hear the idle drop. Sounds like it goes from 1,600rpm to 600rpm from what I can tell.

Ok I just watched it again and yeah that is a little low but the idle before is pretty high, it may be having a problem of having a high idle problem but then it drops to its actual idle, causing you to think its regular idle was the high one.

Sorry if that didn't make sense

Edited by M3NT4L5

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Ok I just watched it again and yeah that is a little low but the idle before is pretty high, it may be having a problem of having a high idle problem but then it drops to its actual idle, causing you to think its regular idle was the high one.

Sorry if that didn't make sense

That actually did make sense lol. But I have tried adjusting the idle in different ways. By the throttle stop on the carb to the barrel adjuster on the throttle by the grip. No matter what I do, it returns to that same low idle every time.

I have parts to pick up at the shop, while i'm there i'll get another plug and run it again so  can get you a good picture of what the plug looks like. Also change the trans oil and may be a good idea to change the fuel too.

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