Tweiser

Member
Nov 21, 2005
4
0
whats the difference between running lean and rich??

whats the difference between running lean and rich??

which is more gas and which is more oil
??
 

Tweiser

Member
Nov 21, 2005
4
0
whats the difference between running lean and running rich

which is more gas and which is more oil???



and most importantly why did my rm125 engine seize up?!?!?! :ohmy:
 

Danman

LIFETIME SPONSOR
Nov 7, 2000
2,211
3
I'm not a good 2 stroke guy, but as far as I know the amount of oil doesn't have anything to do with being lean or rich. The amount of oil/gas is a ratio you set at what ever the manufacter specs for your bike or you fine adjust to you presonal taste. To much oil and you get a nasty spooge running out the pipe and gum things up. To little and you don't get proper lubrication for the top end. Lean or rich relates to the ratio of gas (for a 4 stroke) or a mixture of oil and gas (for the 2 stroke) to air. To much air means your lean. To much gas (or mixture of gas/oil) means you are rich.


Engines seize for a lot of reasons. I'd start by taking the head off and have a look see at the piston and see. Deal with that an it might leave you clues as to what happend. The why part.

You need to list things like your bike year and the ratio of oil to gas you run and maybe your jetting settings for the smart 2 stroke guys around here will be better able to help you out. The more accurate and better input you have the better your answers will be. ;)
 

CaptainObvious

Formally known as RV6Junkie
Damn Yankees
LIFETIME SPONSOR
Jan 8, 2000
3,331
1
Don't confuse running rich and lean with your oil ratio.

Rich & lean have to do with the ratio between air and fuel.

The oil mixture has to due with how much oil is present in your fuel. Of course, the more oil you have in your mixture, the less fuel, so an oil rich mixture provides a leaner fuel/air ratio.
 

AnTs

Uhhh...
Nov 5, 2005
246
0
Just run 32:1 or 40:1....

40:1 Is reccomended for 250's ( bel- rays bottle says so... dont qoute me on this "

I run 40:1 in my cr250 and its about 16 oz for 5 gallons, i put to much oil in once and splooge came out da pipe..

For your engine seize i would guess not enough oil,
 

Tweiser

Member
Nov 21, 2005
4
0
well ill explain my situation. i bought a 1993 rm125 from someone for 800. He said that the bike was built up. he said it was bored and had a new piston and stuff that goes along with that. he said he ran
50:1 ratio for gas mixture. he went to start the bike up at his house and it just turned over and shut off. he said it was because it was cold, and i beleived him. so i took the bike home and and a couple of days later got it out to go riding. i put 32:1 oil\gas in it that my friend uses for his rm85 i went to start it up and it started up for a second then shut off i mean just stopped not stall. like it hit a brick wall and a really think oil came out the exhaust pipe. i tried to kick start it and the kicker was stuck. my friend said the piston probably seized. The guy i bought it off of said that i didnt mix the gas right. but y would it work in my friends bike. i called my local bike shop and they said the gas\oil mix wouldnt make much of a difference. i think that he knew that the bike was gonna break and just sold it to me because he knew i didnt know much about bikes.
it had a pretty bad gas leak he didnt tell me about
any suggestions on what i can do???
 

bleeds

Member
Oct 17, 2005
172
0
I think the safest thing to do at this point is open the topend. Something is really going on in there. IF you are saying it started then almost immedialy seized, then something is way out of spec. Just my two cents, since I am learning as I go too and these other guys are better at this than I am..
Bleeds
 

Gibby

Member
Dec 8, 2004
150
0
Won't learn anything untill you take it apart.If it was just rebuilt like he says then I would guess that one of the circlips came out. But that is just one of the many possibilities. Take it apart and i'm sure you will find the culprit. Good luck
 

AnTs

Uhhh...
Nov 5, 2005
246
0
If you dont know alot about bikes, take it to your dealer have them look at it and ask if you can watch so you can learn ;)
 

guts

Member
Sep 14, 2003
67
0
hate hear that happend ! i would drain oil in crank case look for metal shaveings, or water in the oil, it will look milky if water in there ! next step get a book, they come in handy . if it's the topend you can redo it your self not hard at all . after you pull topend see if the motor turns over bye hand should turn free , if it don't turn over there is the problem ! but if it does turn over it was topend . goodluck let us know what find out !
 

rm_racer

Member
Mar 15, 2005
501
0
Running too much oil wouldnt seize it. Im going aggree that a circlip maybe jammed down there in the bottom end. Also, isn't the 93 cylinder nikasiled? Mine is. (94 RM125, and Im pretty sure it says the 93 is also in the manual).

Pull the head and cylinder off and let us know whats up.
 

adam728

Member
Aug 16, 2004
1,011
0
guts said:
hate hear that happend ! i would drain oil in crank case look for metal shaveings, or water in the oil, it will look milky if water in there ! next step get a book, they come in handy . if it's the topend you can redo it your self not hard at all . after you pull topend see if the motor turns over bye hand should turn free , if it don't turn over there is the problem ! but if it does turn over it was topend . goodluck let us know what find out !

There is no oil in the crankcase of a 2 stroke. The oil is only in the transmission/clutch area.

I would start by pulling the head and cylinder and checking things out, like everyone else said.
 

guts

Member
Sep 14, 2003
67
0
adam728 said:
There is no oil in the crankcase of a 2 stroke. The oil is only in the transmission/clutch area.

I would start by pulling the head and cylinder and checking things out, like everyone else said.

no disrespect ! but if you didn't put oil in the crank case then you tranny or clutch would not be running in it either 2 cycle or 4 cycle !
 

adam728

Member
Aug 16, 2004
1,011
0
guts said:
no disrespect ! but if you didn't put oil in the crank case then you tranny or clutch would not be running in it either 2 cycle or 4 cycle !

I think we are looking at it differently. There is oil in the tranny, yes. But in the lower end of the engine there is no oil on a 2 stroke. The crank bearings and lower rod bearing are lubed by the oil in the premix, not the oil you put in the transmission.
 

guts

Member
Sep 14, 2003
67
0
adam728 said:
I think we are looking at it differently. There is oil in the tranny, yes. But in the lower end of the engine there is no oil on a 2 stroke. The crank bearings and lower rod bearing are lubed by the oil in the premix, not the oil you put in the transmission.

lol yeah i know what your saying ! but i had say that :nener: no harm done !
to orignal poster not trying jack your thread ! we get back on track .
 
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