I Hate Carbs!

[Wacked]

Just like Great Buffalo hates mud - I hate carbs. 

Anytime my fingers touch one, it ends up a Poo-Fest.  So I try my hardest never to touch them.  Well the past few weekends I haven't been able to get my daughters DRZ125 running.  Pops off with starting fluid but won't stay running. 

Saturday I broke down, and took the little Mikuni apart and cleaned up every orifice and put it back together.  Nope, wouldn't start and I'm pissed.

24hrs later while waiting for my charcoal grill to heat up and, to fill the time, I can't resist giving it a kick.  "Wah-Lah" on the 2nd kick she went.   Why'd she decide to wait 24hrs before running and why is she dripping gas all over the floor?

So here's my question: Is there a good Mikuni resource/tutorial out there?  Or is there some guru that I can send this carb to whereby he bench tunes it and sends it back to me ready to rock-n-roll.

I don't trust it.

Wacked

[Hank]

I feel your pain.   I cannot get the carbs on my TDM quite right.   At least I think its carb related..

Anyway, I don't know of a tutorial.   Most decent bike shops should be able to go through it, set the float level, etc on the bench though.

[Osnabrock]

I've looked around the Thumpertalk forum for many of my carb settings.  Of course there are a lot of variables in setting a carb but their knowledge has gotten me close enough for my needs.
They have a forum for the DRZ125 too.  They even have a jetting database that might help you out.  Here's the link. http://www.thumpertalk.com/forum/26-dr-z-125125l250/
Maybe there will be some information that you'll find useful and perhaps you've already checked it out.

[plumber mike]

The float set too high could have flooded the bike. Turn off the gas-go do something else- come back and wa-la....it runs. The float level may be your only problem. If you get it running quick enough after turning the gas on, and it does not leak gas when running(consuming the fuel rather than leaking) then that is the first place to look. The next for me would be to check the mating surfaces of the float needle/pin and seat. As they wear in, they seat at a slightly different level requiring the float level to be adjusted accordingly. One adjustment at a time and retest. I use the choke/air butterfly as my jet-o-meter on most bikes. If it runs better with the choke on a little, you may have a lean condition. If removing the air removes some power, then you are probably ok to fatten the jets up a size or two.

I don't think this is how the pro's do it, but I have brought a few dead bikes back to life using these techniques. I have no Mikuni specific information to offer.

Looking forward to riding together soon! Best of luck on the repairs.

[Hank]

Float set too high, or a pieced of crud under the float needle, or my best guess is the bowl oring is dried up.  I've had it happen where the dried up bowl orings won't seal once you've cracked the bowl loose.
You can soak old orings in brake fluid for a couple days and it will soften them up.

[Bogus Jim]

This might be the best way to fix that carb.   

[Wacked]

Guys - Thanks for all the imput!

I might be Wacked, but not crazy enough for the EFI conversion.  Nice, neat package UNTIL you get to the fuel delivery system......  That was some funky home-brewed plumbing for the gas.

OK, I'll try it 1 more time.  Some Thumpertalk articles boosted my confidence - thanks John.   I'll order some Procycle parts and have another go.

Wacked

[Dr Psyko]

The carbs on the old race karts were notoriusly sensitive. Used to take them down after every race wknd to clean and redo. Float height is a big one people miss, also needle seal. With an older carb, soak in kerosene (after dimantled) to disolve any old varnish, all jets in and out, then blow compressed air through all orifices. We raced with methanol which was hell on carbs. Change all rubber if possible (old carbs particularily hate etoh mixtures, makes a chalky oxidation substance from aluminum when it dries, cracks the rubber gaskets, etc.). Used to be all sort of cheating done through the carbs, hidden vent holes to get more air through the measured spec throat, knife edged butterflies, radiused slides, etc. Used to race an eye surgeon who got caught in after race tech inspection with a carb body with dozens of microscopic holes in the underside of the carb. Had been using a surgical laser to cut them.

[greatbuffalo]

Win at all cost they say.

[Lee Bruns]

Come over to Watertown. I teach flks how their motorcycle works. I'll go through the carb WITH you, teach you to fish, so to speak.