Changing Ratios

[bobby]

I have a 98 kdx 220 with the RB carb. The bike runs great - the plug is perfect, but it's spooging like a rusty asphalt truck. I'm running 40:1 Bel Ray H1R. If I go 50:1, what type of mixture changes would you recommend.

 

[BRush]

If you go from 40:1 to 50:1 without rejetting, you'll be running richer than you are now (the fuel charge going into the engine will contain more fuel and less oil), so you'd probably want to look at rejetting. There are a number of people who run 50:1 here so my advice is to post your current jetting info:

Main jet size
Pilot jet size
Air screw pos
needle size
needle clip position
altitude and temp range
carb slide (if you know it - typically #7 on an RB mod)

and see what replies you get.


ps. For what it's worth. I switched over from H1R to Mobil MX2T last year and noticed less smoke and less spooge at the same ratio (40:1) AND jetting. H1R also seemed to leave my power valves with a lot of residue.

 

[canyncarvr]

RBs and jetting

Hey bobby!

You been to: (dang..thread's too long to fit on a line...)

Anyway..name of the thread is

EMERGENCY RB Designs Jetting Info Needed

Look for it.

It's been awhile since I read the whole thing from the beginning, and I don't see your name on the first few pages...don't recall seeing you there.

If you haven't benefitted from JD's input to the RB carb jetting issue, then you have a LOT to look forward to!!!

The first efforts at jetting the carb (AEG, AEN) were WAY off!! With a CEK/L you'll lose the spooge...see nothing but a DRY 'tailpipe'!!

Works for me!!!!!!!!!!!

Not to make this an oil thread..but, dang...h1r stinks!! Cold seized my bike on the first pint of the crap!!

..not that I have an opinion on the matter............