Welcome guest, is this your first visit? Create Account now to join.

Welcome to the Motorcycle Forum.

Register ButtonIf this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed.

+ Reply to Thread
Results 1 to 15 of 15
  1. #1
    Newbie
    My Bike(s)
    2001 RM 125
    Location
    San Diego
    Posts
    6

    urgent. regarding rm 125

    Hi i have a 2001 rm 125 and was wondering if anybody knew how to check the compression on it with a compression tester or if anyone knew what the stock compression should be? Thanks in advance.

  2. MotorcycleForums.net is the original Motorcycle Forum! Registered Users do not see these ads. Please Register - It's Free!

  3. #2
    Third gear and cruising
    My Bike(s)
    2005 GZ250 1973 "heavyoldandslow" GT750
    Location
    Roland, AR
    Posts
    510
    Just install the compression tester and kick the engine over until you get the higest reading on the gauge. My '73 GT750 3cyl 2-stroke makes about 120-130psi per cylinder with the engine cold and thats 250cc per cylinder. If you get a low reading add a few drops of oil to the cylinder and try again, and if the reading is still low then you may have worn rings or a head gasket problem. Post your results.
    Last edited by 2005GZ250; 11-09-2006 at 05:00 AM.
    I only ride 'em. I don't know what makes 'em work.
    Oddball: Donald Sutherland, Kelly's Heroes 1970

  4. #3
    In Training
    My Bike(s)
    C90T Boulevard
    Location
    Arkansas
    Posts
    146
    Quote Originally Posted by 2005GZ250
    Just install the compression tester and kick the engine over until you get the higest reading on the gauge. My '73 GT750 3cyl 2-stroke makes about 120-130psi per cylinder with the engine cold and thats 250cc per cylinder. If you get a low reading add a few drops of oil to the cylinder and try again, and if the reading is still low then you may have worn rings or a head gasket problem. Post your results.
    You said that wrong. If you add oil and the reading comes up then you have bad rings. If the reading remains low then you have bad valve problems. Or a very big hole in a piston. lol

    Also for a proper compression test, take out all the spark plugs to run the test.
    C90T, 2006, PowerCommander, Hard Krome 3inch big straights, K&N Air Filter. Love.

  5. #4
    Third gear and cruising
    My Bike(s)
    2005 GZ250 1973 "heavyoldandslow" GT750
    Location
    Roland, AR
    Posts
    510
    He has a single cylinder 2-stroke engine and there are no valves to worry about and when I tested my 3 cyl I did remove all the plugs.
    I only ride 'em. I don't know what makes 'em work.
    Oddball: Donald Sutherland, Kelly's Heroes 1970

  6. #5
    Newbie
    My Bike(s)
    2001 RM 125
    Location
    San Diego
    Posts
    6
    Cool thanks a lot guys, now does anyone have the specs for a 2001 rm 125, what the compression should be in psi?

  7. #6
    Third gear and cruising
    My Bike(s)
    2005 GZ250 1973 "heavyoldandslow" GT750
    Location
    Roland, AR
    Posts
    510
    I don't know the specs but what kind of problem do you have?
    I only ride 'em. I don't know what makes 'em work.
    Oddball: Donald Sutherland, Kelly's Heroes 1970

  8. #7
    Newbie
    My Bike(s)
    2001 RM 125
    Location
    San Diego
    Posts
    6
    My problem is a lot of oil coming out of the pipe. I got the bike with a rebuilt engine including main bearings and piston and rod and everything. Rod about 8 times, 6 hours a piece. When i first got it it didnt put a drop of oil out for the first 3 rides, now its been constant. Starts and runs just like it did day one- perfect. Its got the fmf fatty and turbine core 2 with v force reeds. Have never had a problem starting or running this bike. and performance hasnt dropped at all. Also i have been using the exact same oil and oil mixture since day one,32:1 So why is all this oil comming out of the pipe?

  9. #8
    Newbie
    My Bike(s)
    93 Vmax
    Location
    Ontario
    Posts
    13
    It should read around 120 psi. If it starts within the first few kicks....usually means no need to check compression however. Check to make sure. When the bikes compression drops too low it will start getting harder to start and your saying it starts fine, so how much oil are you mixing with the gas ? 32:1 are you sure ? If you add too much, the bike will spit out oil from the pipe. Your tranny (GEAR) oil has no contact with combustion chamber...thats why you have to mix the gas with oil for 2 stroke engines. Buy a mixing funnel and measure the mix...the key is don't over/under the mix ratio. Refer to owners manual. This you probably already know....Try using a different 2 stroke oil. I use redline - it says you can mix as little as 100:1 but I mix a 25:1 with no problems. I also suggest (if it running good) get out there and giv'r sh*t and burn all that extra oil up in the pipe. Run it hard ! If you still seem to be having problems, drain all the gas and take off the pipe and clean it - refill tank, then your starting from scratch. If it still smokes bad or spits oil *you need to check with a dealer*.
    Last edited by Robbie C; 11-16-2006 at 07:47 PM.

  10. #9
    Leaned over, knee down
    Location
    St Paul Mn
    Posts
    4,801
    When was the last time you cleaned your air filter?
    2009 BMW, R 1200 GS
    2010 Victory Cross Country
    2008 DR 650
    2004 BMW R1150RS
    2003 KTM 525 EX/C
    2005 Santa Cruz Heckler

  11. #10
    Newbie
    My Bike(s)
    2001 RM 125
    Location
    San Diego
    Posts
    6
    O trust me, i service my bike like crazy! I cleand the air filter 2 rides ago. No difference if i clean it or not, but i still clean it at the most 3 rides, say if i go for a short ride then i let it get to 3 rides. But the filter im always cleanin because thats like the heart of a 2 stroke- gotta have clean air goin in. Hmm

    120psi??? wow, i got 174psi. for the compression test. But anyways i do have a "ratio rite" measuring cup and always measure exactly 32:1 in my gas. Maybe carb needs to be cleaned out or what? I have v force reeds, would that have something to do with this problem?

    I have already repacked the exhaust btw, it even leaks out of the little conjunction to the rear silencer... hmmm

  12. #11
    Clunked into first gear
    My Bike(s)
    2000 yz125 race prepped
    Location
    bentonville, arkansas, us
    Posts
    230
    spooge means you're running rich. learn to read the plug. If its black and wet, you're too rich, if its white you're too lean. A brownish tanish color is perfect. when rejetting (do it yourself, its easier than you think and they way overcharge at any shop, just use the manual) go down one size at a time on the main jet and do a plug test after every change. for the pilot and needle jet, going by feel is the best way to decide adjustments.

    btw 174psi is good, 120 would be ok for a bike made in the 70's but for a modern bike it'd be time for new rings

    you should probably repack the silencer also

  13. #12
    Newbie
    My Bike(s)
    2001 RM 125
    Location
    San Diego
    Posts
    6
    Quote Originally Posted by the_privateer
    spooge means you're running rich. learn to read the plug. If its black and wet, you're too rich, if its white you're too lean. A brownish tanish color is perfect. when rejetting (do it yourself, its easier than you think and they way overcharge at any shop, just use the manual) go down one size at a time on the main jet and do a plug test after every change. for the pilot and needle jet, going by feel is the best way to decide adjustments.

    btw 174psi is good, 120 would be ok for a bike made in the 70's but for a modern bike it'd be time for new rings

    you should probably repack the silencer also
    Thanks a lot for the reply. I will re-read the manual on how to adjust it and take the carb off and re jett it. hmmmmm, ok ill give it a try. Thanks again

  14. #13
    Clunked into first gear
    My Bike(s)
    2000 yz125 race prepped
    Location
    bentonville, arkansas, us
    Posts
    230
    let us know how it turns out (I thought my bike ran good until i learned how to jet) and remember if its too rich you may foul some plugs-no big deal, but if its too lean you can seize it up, so check that plug often when making adjustments

    while you're working on it, take the expansion chamber off and hang it vertically so all the oil can drip out, if theres carbon build up inside it you can drop a half dozen or so nuts in it, plug the ends and shake the %%%%% outta it and it will loosen that crap up so you can shake it out, just count how many nuts you put in and make sure you get 'em all out

    I just noticed you said you already repacked the silencer, is this when it started spooging?, that would make sense because the 'glass was probably so saturated with oil that no more could get through and that is why it started spooging when you repacked it. not that it changes anything but just trying to figure out why it didn't spooge for the first few rides. spooge is a funny word
    Last edited by the_privateer; 11-30-2006 at 06:33 AM.

  15. #14
    Newbie
    My Bike(s)
    2001 RM 125
    Location
    San Diego
    Posts
    6

    hmm. more ideas.

    Quote Originally Posted by the_privateer
    I just noticed you said you already repacked the silencer, is this when it started spooging?, that would make sense because the 'glass was probably so saturated with oil that no more could get through and that is why it started spooging when you repacked it. not that it changes anything but just trying to figure out why it didn't spooge for the first few rides. spooge is a funny word
    No it started spooging maybe after 3-4 rides after i bought it. Im so lost. After i changed the packing, there was no difference. wich is interesting. I would expect the packing to at least suck up oil untill it was full then start spooging again out the tail pipe but i did it right off the bat- if i remmeber correctly. O and wich way do i hang the expansion pipe upside down? With the big opening(end that comes of the head) to the top or bottom?

  16. #15
    Clunked into first gear
    My Bike(s)
    2000 yz125 race prepped
    Location
    bentonville, arkansas, us
    Posts
    230
    you could probably hang it either way, i did mine big end up

    again the spooge has very little to do with the packing and everything to do with jetting


 

Ads

 

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts

Similar Threads

  1. Urgent Need Help
    By kevinm7609 in forum Marauder M50 Secret Hideaway
    Replies: 12
    Last Post: 06-27-2006, 12:50 PM
  2. Urgent, Do Your Rear Ambers Work?
    By yukaputz in forum Marauder M50 Secret Hideaway
    Replies: 3
    Last Post: 02-25-2006, 05:29 PM

Search tags for this page

01 rm 125 specs

,

2001 rm 125 compression

,
2001 rm125 compression
,
2005 rm 125 compression
,
how to check compression on a 1995 rm 125
,
how to do a compression test on a rm 125
,
how to test compression on 1995 rm 125
,
rm 125 compression
,

rm 125 compression readings

,
rm125 transmission oil level
Click on a term to search for related topics.