RM250X Jetting Question

[Slow Pete]

Hello All,
             My RM250X [81] is running a bit rich, I have striped down the Carby and the only thing I can find is the the needle jet is a R9 rather than a R8 despite the manual saying R8 is as rich as they go.     The clip on the needle has 2 more rings to lean it off a bit, will that be enough to compensate or should I get a leaner needle jet ?

Wont be able to test ride it for another couple of weeks so just trying to save some time.

Also I'm considering buying a single sided air-box [Works replica]  for no other reason that it will be easier to access the carb etc the current air-box set up is a shocker.  Has anyone any experience with them before I spend my hard earned money ?

Just returned to MX after 30 years out of it, but things are starting to come back to me.


Thanks

   

[evo550]

What part of the throttle setting is it running rich ?

[Slow Pete]

Right through the mid range, almost felt like the choke was stuck on, but that seems to be ok. 

[alexbrown64]

Well Pete, you have 2 notches to play with.  Go up a notch to drop the needle and see if it clears up a bit.  You can always go up to the top notch and see if it clears.  Otherwise you can go to the next leaner needle jet for your mid range richness.  MikuniOz is pretty good at sending stuff out.  A R-9 has a 2.795 orifice opening and a R-8 has a 2.790.  Sounds like the previous owner wanted to richen up the midrange a bit.  The specs here.. http://www.ozebook.com/compendium/techbuls/SerBulletin%20Specifications%2017j-17s.pdf  call for a R-8 for your bike so your on the right track.

Cheers,
Alex

[PCMAX]

Because we love new members and you may not have found some other links to all things Suzuki and Mikuni, here's a couple

http://forum.ozvmx.com/index.php?topic=28857.0

http://forum.ozvmx.com/index.php?topic=31710.0

Lots of other interesting stuff in the first link to the "skydrivelive" site

[Slow Pete]

Thanks Guys, I appreciate the help. 


Pete