Jump to content
Sign in to follow this  

2001 RM 125 project

Recommended Posts

Just bought this a few weeks ago and plan to get it in good shape over winter, not trying to make it bling but just make sure its a solid reliable bike, it wont be raced so it doesn't need a bunch of performance $ thrown at it. I have little experience with 2 strokes and looking for some guidance here. It cranks easily but its bogs down when I really twist the throttle. It is suppose to have a recently new top end, I think that I could do a top end just from watching youtube. How do I check the crank or know if it needs bottom end rebuild? 

 

IMG_20151031_174653.jpg

Share this post


Link to post
Share on other sites

First you will need a manual. Then to check the crank, pull the cylinder off. Remove the piston and measure the conrod small end ID. Rotate the crankshaft a few times and listen carefully, the crank bearings should not make any noise. Take the conrod and try move it up and down, there should not be any play. There will be side to side play. Take the mag cover off and hold onto the flywheel and try to move it in and out then side to side, there should be no play. I think that is about all you can check without splitting the case but if all checks good then your crank is probably fine. If it is obvious that the piston is new then just reuse it.

 

Check the jets and needle in the carb. If you live at an elevation of 0 - 1,500 feet and normally ride the bike in temps close to 70 degrees then the stock jets and needle should work just fine. If someone changed the jets then this might be what is causing the bog.

 

Check the reeds and make sure they are not damaged at all. 

 

Using the manual, just check over all the basic things like correct spark plug, proper lever play, sag etc...

 

It looks really clean for a 2001 so hopefully there arent too many issues with it.

Edited by ManBearPig.

Share this post


Link to post
Share on other sites

Its been a while since previous post, bike looks much better. New tires,tank(old one was cracked), plastics, removed dents from pipe. When cold start the bike revs like crazy without me touching the throttle, I put it in gear and lug it around for 5-10 mins until its warm. After that the bike runs great, starts 1st or 2nd kick without choking, no splooge. Any idea why it initially runs like this when I start it up?

Share this post


Link to post
Share on other sites

got pics of bike now ?

 

have you cleaned the carb ?

what jetting is in there ?

 

standard jetting should be :

pilot :27.5

needle size : ?

needle clip position : 3

main jet : 460

slide : 5.75

air screw : 1.5 turns out (anti clockwise from lightly bottomed out)

 

pro circuit recommendations (just use this to get you started)

pilot : as above

needle size ?

needle clip position : 2

main jet : 430

air screw : as above

 

this is all based on sea level to 1000ft and 32:1 (i'm guessing north carolina is 0-1000ft elevation)

( i recommend a low flash point oil mixed at 40:1 seems as your not racing the bike)

 

google spanky's jetting guide to learn how to set the air screw up properly

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×
×
  • Create New...