Two things I completely forgot to mention, first use fresh gas. Also take everything off the carb before you install it and I mean everything, use a brush, soap and water to scrub the outside of it. Then soak every metal part in parts cleaner overnight followed by blowing all the holes out with compressed air. Be careful, there's one dead end in this carb and may blow back in your face if you're not paying attention.
Rinse in water, allow to dry.
Reassemble. Jetting a dirty carb or with out of spec valves is a waste of time and effort.

Good jetting tips Smac!

I did the valves already when i first got the bike and only put an hour on it so they should still be good to go...  

Just picked up a 03 KX65 Carb for $50 on Fleabay with Cable and throttle.. and ordered up main jets from 100-135 and Pilots from 15-30...  Sure hope it works!  I think I am going to try and dial it in with the stock pipe before ordering a new one....  Should have everything by next weekend to do some tuning.

I am making this my main Mini Bike for the season as I am getting too old and fat to ride the built 50's anymore  

Got the Carb and Jets in the mail yesterday so I am ready to bolt her up and start dialing it in for completely stock settings...  Just needs a good scrubbin before it goes on....

I will report back on the progress... I really hope this is a solid fix for the Stock VM20 that comes on these bikes like it is for the TTR guys...

Something tells me it's not going to be easy considering this carb is not a pumper!

Ok... Got a good start on tuning the DRZ with the KX65 Carb last night.....

I started with a 110 Main, 20 Pilot, Needle @ Middle Clip, Airscrew 1 1/2 Out...

It started and had a perfect idle on the first kick... but that was about it. It did not want to rev up and pretty much just died with any amount of throttle.  I worked the Pilot up to a 40 and it kept getting better with every Jet Size... (Def compensatiing for not having the 4 Stroke Circuit)

I ended up with a 120 Main, 40 Pilot (Stock KX), Needle 2nd clip from top, and Airscrew 1 Turn out.  the more I turned the Airscrew in the more it got over the dead spot from about 2000-4000 rpms.  I think I will need to go to a 45 Pilot to dial this in just right....  However it was reving VERY strong and over all this is the best I have had this bike running since Ive owned it!!

I was tuning with a Pod Filter on it as well... just trying to get a decent start. I will try and find a 45 Pilot and put the Airbox on it tonight ... Should fatten it up some and help with the 1/4 throttle dead spot hopefully.

All in all I think it's going to work great once I get the fine tuning dialed in... For $40 bucks (with the throttle and cable) this may be a great replacement DRZ carb!  and its a real OEM Japan Mikuni

I will keep working on it and share my settings once I get it just right.....

Nothing beats some good tools, this should help you:


This is ugly, but as far as what pieces affect which throttle positions and how much of an affect, it's pretty accurate:

I tried the 45 pilot and it doesnt start as easy and still has the dead spot @ 1/4-1/2 throttle ... So I think the 40 is gonna be as good as it gets on the Pilot Circuit.  It revs out hard and clean so I may be able to go up 1 more size on the main to help with the transition as well....

Should I try a Richer Needle?  

It helps a TON to go all the way in with the Airscrew so I am assuming it still needs more fuel on the bottom/Transition to the Main circuit....

Try moving the needle clip. Move the clip towards the blunt end makes it lean, moving it towards the point makes it rich - specifically in the 1/8th to 2/3rds throttle range after putting the 40 pilot back in. You may find that you'll need a 42.5, but you can probably get by with needle and main adjustments instead.
Very, very few people ever change a needle's taper or straight diameter characteristics and few ever mess with clip positions.

I moved it to the 2nd clip (from the top) already ... So I have one more to go to get max richness out of it...  I will try that and go up on the main a size and see if it cleans it up!


Thanks for the help!

Still no luck on elimiating the "bog" from about 1/8-1/3 throttle... I am starting to think this KX65 carb might be a loss... I might have to move forward and pick up a 4 Stroke Carb to make this this thing run right

At least with the amount of mini bikes I have.. this VM24 will find a new home someday....

I don't know how the TTR guys are making them work right

MiniBikes4Life said:

If I had time and complete spare carb, I'd throw it on our KLX125 and see if I could help you out. But our spare carb is missing a few vital pieces like float needle (lost in yard AGAIN!) and needle clip which completely disappeared.

Oh, TT-Rs will also run (not well, but run) with some really funky settings.
This is what I found when I separated the cap on the slide on our TT-R225 carb and yes, it ran pretty well like this. I couldn't understand how it ran with NO NEEDLE! Then I opened it and saw the needle was out of place.

What needle does your carb have in it?

I'm pretty sure its the stock KX65 needle... I will look tonight and post up

Its a 5HS59..

It looks straight.. I have it on the last clip (richest) and I didn't really get much difference moving it up from the middle-- my starting point... to be honest. the pilot changes and air screw seem to have the most effect on the problem area...

I ended up with a 120 main and that seems to be spot on... 125 was just a tad too much..

I think a 42.5 pilot might be the best option .. haven't tried that yet just 40 & 45.. as soon as I went to the 45 the nice easy 1st kick start and steady idle went bye buh... So i have a 40 in it now.

I would try a different needle as well. The YZ80 stock needle (5L1) seems to work good on my TM28 and my VM20. I'll double check the needle tomorrow, but it sounds like you should try the 42.5. Did you put the air box back on? It really makes a difference!

Yes, I've had the airbox on the last few days I've been playing with it.

I will pick up a couple needles to try out and see if that helps... It's def bogging out on the Pilot/Needle circuit -- transition to the main..  If that makes sense.

Dumb question, is your muffler packing good? I know I see way too many people riding around with completely crapped out packing. While you'd still likely be able to jet it right, you definitely want to start where you should be and not have to fix it later.

Yes, muffler is in showroom condition

Sorry, out of ideas. Must be the dry desert air?

I think its just the 2 stroke carb set up that is causing the issue... Needs a pump shot!

Does anybody know if there different slides for the VM24?