carb tunign question... GRRRR

[XPS1210]

Arreche (Spanish made) 19mm carburator...


okay... I got where the lines all hook up and all that... Have over 400 miles on new carb but wasn't happy with tune so I installed the colder plug (9) as it's supposed to have (they finally came in today)...

When I check my plug reading... It was light grey... Not good... So I thought I richened it up and it was almost white the next time... So I turned the screw the other way and no change... I went over 2 turns each direction...

Now that was between idle and WOT... I'm sure I need a larger jet as my WOT is light grey all the time with the new plug... and the idle barely made a brown color but still didn't look correct...

The question I have is... idle to 1/4 is the idle screw, right? Then 1/4 -3/4 is the needle? and then up to WOT from 3/4 is the jet...?

So do I drop the needle down or up to make it richer? and the idle screw isn't making a difference that I can see... this will change with a large jet, right?

[Lennox]

up with needle size=more fuel.

Have you tried tuning with a tachometer? Plug chops are not the best way to tune.

It takes way too long to get an acurate reading. :confused:


If you want to get it tuned to perfection, you need an EGT guage. E=Exhaust G=Gas T=Temperature. This will dial you in to perfection!! ;)

Check out DIGITRON. They make a great guage.

[XPS1210]

yeah, so I went to check the jet size in mine and the DAMN thing broke in half... Now I have to wait till I can find a new one to ride!


!@#%@#^@#$*(%!@#*( if you know what I mean....

[Bad*Brad]

Jered,

Theres a shop not to far from my house that has all kinds of jets, let me know what you need and I can pick one up for you perhaps.

[XPS1210]

brad if they have a 95, 100 or a 105 mikuni large hex main jet... Thats what I need... I'd paypal the cost to you if you can get them from the shop by your house...

The best I could find was a 3 week out order....

[Bad*Brad]

I'll run up to the shop tomorrow morning, needing some oil anyway. Let you know saturday noonish my time.

[vailitrev]

Along with all of your Mods, what type of 2-stroke injector oil do you use?

[XPS1210]

I use Motorex (oil of switzerland) Cross Power 2T (fully synthetic)


The directions on the back state:
Fully-synthetic high-performance motor oil for 2-stroke motorcycles, Race-lubrication tested formula, Maximum reliability, Extremely clean combustion, specially formulatedfor use in endureo and motocross engines, suitable for mixed and seperate lubrication, mixing ratio up to 1:100 (1%)

This is the stuff the MTX (or what ever that brand of motocross bikes are called) use in their race bikes...

It's on the spendy side but it's best stuff I could locate here in anchorage... Costs me $13.95 a quart...

I think I'm going to start running a premix as well as the injector... That way I'm even better lubricated, however I have to figure out the mixture I need...

[Lennox]

Are you going strictly premix? 50:1 with a good synthetic . If In addition to injection I would go 400:1 or so...... you dont want to be fouling plugs

[Elliott]

Any body know Why the Carbs Freeze up and water starts Driping from the side of the Carb Any of yal have that Problem :confused:

Thanks....

[XPS1210]

I'd check and make sure that the needle assembly is installed correctly and not turned sideways or anything...

2nd, there should never be "WATER" coming from your carb... Maybe fuel if it is stuck at WOT and dumping fuel all the time... If you have the needle assembly installed incorrectly then it is possible that there could be space between the top of the carb and the part where the cable connects (I'm assuming you have an upgraded carb?)

[Elliott]

What do you mean sideways theres a Special way that Needle go in there!!

Jered..

[XPS1210]

no... On the 19mm carb I have the needle assembly can be put in place with out the groove lined up properly and this will cause the needle valve assembly to be "stuck" I started doing this once and saw what I had done before I tried to tighten the 2 screws down...

Just a thought anyway...