84 RM500 JETTING

[Stevo17]

I replaced the flat slide in my 84 KX500 and found the new ones have a different slide and needle jet series to the old OEM one. Yep it is ready for Monza !

[JohnnyO]

Stevo what carb did you put on your '84 KX500? I put a round slide on mine cos the std flatslide was shite even with a new slide...

[Stevo17]

Hi John,  I put a new TM38-85 on it to replace the original TM38. I had to try out a few different needles but it seems best with the one that comes stock with the carb 6FJ41 I think it is.  Specs are further back on this thread.

[JohnnyO]

Hi John,  I put a new TM38-85 on it to replace the original TM38. I had to try out a few different needles but it seems best with the one that comes stock with the carb 6FJ41 I think it is.  Specs are further back on this thread.

Thanks mate

[POM]

Got the new carb last fri tm38 85 $155 delivered

jetted it as follows

main 320

needle jet r2

needle 6fj41

pilot 35

stuck it on sat arvo ready for viper practice sun,started easier,idled smoothly and felt reasonably crisp.....progress methinks.

alas sun at ravenswood the power delivery had a huge hole right in the middle of the rpm range,seemed rich so i dropped the needle all the way in(leaner).....even worse....lifted it back out 1 past middle(richer) improved......fitted r4 needle jet(richer) needle still 1 notch rich.....absolutely usless...oiled a plug in seconds......at this point bike was for sale....pis*ed off with it.....
Dropped needle all the way down again and wow!! different bike....smooth idle reasonably good mid...huge top end with no detonation....still not perfect but better than its ever been.
thanks to arno #72 for restraining me when i was about to take the hammer to it.

And this is how its going to stay for monza next week......whos' going?....

[Stevo17]

Cool, glad you have it nearly sorted.  That is the same jetting as my KX that I mentioned at the start of this thread.  I will be lining up next to you at Monza