RM125A jetting specs

[bigk]

Hello all,
Can anyone tell me the jetting specs for 1976 RM125A? Standard engine.
Cheers,
K

[cyclegod]

On the stock 32mm Mikuni

Pilot jet = #30
Needle jet = R-0 (R-3 is the go though)
Needle = 60P5-3
Main jet #250-260 (factory options range from #210-#310)

[bigk]

Cheers, That will be our starting point.
Thanks,
K

[Graeme M]

I haven't the specs to hand, but I don't think it'd be a 60P5 needle - I'm guessing 6DP5.

*Edit: I went off for a search to see if this is correct, and in the process found this very useful page. Scroll about halfway down, plenty of tech bulletins for RM series from 75-77 or so. Includes the change from R-0 to R-3 for the RM125A.

http://www.ozebook.com/compendium/techbuls/index.htm

[rm1976]

trying to jet my 125s bogs badly down low pilot 20 main 180 needle top clip plug looks grey white any ideas

[TT5 Matt]

VERY LEAN up the jetting on all stages,check float level,check for manifold air leaks

TT5 Matt

[rm1976]

great idea mat ...the thing is bike has new case seals,float levals checked, manifold is good and if you try to go richer anywhere its un rideable?       half to full throttle is great its just down low it wont pull
any ideas ?

[Lozza]

Learn how to read a plug, check ignition and what heat range is the plug?

[rm1976]

ignition seems to be working good plug is b9es and is grey/white after a hi speed run ?

[Maico31]

20 pilot is too small.. try a 30 or 35.

[Freakshow]

Check the CDI.  got a spare you can swap in for a test.  I smell zoki black box

[Lozza]

What check ignition means is to put a timing light on it and see if the timing mark correspond with the manual settings, not taking it out of the head and kicking it and watching the sparks!Your way to lean on the main should be around the 280 main jet.DO a plug chop when it's bogging and read the plug.

[rm1976]

hey guys thanks verry much for the input i think we are almost there, I went for a ride today and the bottom end is a lot better in fact verry good specs are mainjet 170 pilot 27.5 needle 3rd clip mixture screw2.25 turns.plug B8es grey in colour..............
its still a little doey down low but hey its a 125, and flat out in top gear it seams to hit a bit of a wall like it hits the rev limiter, maybe i am reving it too hard and expecting too much

[TT5 Matt]

still too lean,plug should be tan colour    start rich and go down better than holed or siezed piston because of excess heat caused by leaness not to mention lack of power and flat spots,go play some more with the jetting

TT5 Matt

[rm1976]

18o main makes it run like a pig  i will try different pilot jet(thanks mr hattrick)