Tuning a carb

[Freakinout]

This is a great walkthrough from the people at factorypro.

http://www.factorypro.com/tech/carbtun.html

[03SSgt]

Talk about good tips!!!

[bikeaholic]

in addition to freakin's tuning specs-more carb info


http://members.aol.com/roundr1/CVK40.html

[Whitey]

Great find, thanks

[Freakinout]

This is a guide for installing a jet kit on a ex500

http://www.factorypro.com/magazine/I...500,Rocky.html


Quite helpful for the 500 people out here and a good reference for any other bikes too.

[03SSgt]

This sounds kinda weird for me....

Exhaust Air Injection Block-off Procedure
OK, put the carbs back in the bike.
Notice there are two tubes ( one from each valve cover ) coming from the engine that meet at a metal assembly (exhaust air injection system). Here, one small tube goes down to carb and one large tube goes to the airbox (to the rear of the carbs). You must have this system blocked off or SERIOUS popping will occur. So, what I did was take a ball, about the size of the ball in my MS Mouse, and shove it in the tube coming from the black box. Then, I taped shut the hole in the air injection system that was left open from the tube. Then, just to be sure, I taped the tube back onto the injection system. This will cut ALL airflow to any of the other tubes, thus making the system useless and cutting ALL backfiring and popping out. The general idea is that you just have to stop all airflow between those tubes, the carbs, the valve covers, and the airbox. Do it however you like.


Took that from that carb tuning page, isn't it bad to do this????

[Freakinout]

Originally Posted by 03SSgt

This sounds kinda weird for me....

Exhaust Air Injection Block-off Procedure
OK, put the carbs back in the bike.
Notice there are two tubes ( one from each valve cover ) coming from the engine that meet at a metal assembly (exhaust air injection system). Here, one small tube goes down to carb and one large tube goes to the airbox (to the rear of the carbs). You must have this system blocked off or SERIOUS popping will occur. So, what I did was take a ball, about the size of the ball in my MS Mouse, and shove it in the tube coming from the black box. Then, I taped shut the hole in the air injection system that was left open from the tube. Then, just to be sure, I taped the tube back onto the injection system. This will cut ALL airflow to any of the other tubes, thus making the system useless and cutting ALL backfiring and popping out. The general idea is that you just have to stop all airflow between those tubes, the carbs, the valve covers, and the airbox. Do it however you like.


Took that from that carb tuning page, isn't it bad to do this????

Only if you live in a place that checks emissions, otherwise it makes the bike run much smoother.

[bikeaholic]

commonly refered to as "marblelizing" -part of the epa pollution system

with aftermarket pipes this is usually done to stop the exhaust pop on deceleration
caused by the system injecting air into the exhaust-this extra air when ignited
causes popping- should not affect perfromance but may reduce fuel mileage a little

some folks remove all the hoses altogether and block off the ports with "coasters"
which is a more effective way but the marble trick works fine

[03SSgt]

Well, I'm gonna give this a shot this afternoon, because my engine deceleration popping is driving me and the neighborhood insane! Thnx for the tip

SSgt Andrus

[bikeaholic]

keep in mind sarge-that it might not go away totally-but it should make a difference
some pipes will still pop a little even after the marble

[03SSgt]

UPDATE

Worked like a charm There is still low level popping but the HUGE backfiring and always constant popping is G O N E, wooohooo. It actually sounds like a bike now, instead of a WWII German machine gun.

Now I gotta figure out how to eliminate my "carb farts" at 3.5-4.5K rpm's. I've tried altering the height of the needles, but the "farts" won't go away. One friend suggested larger pilot jets, any suggestions on this fellas?

SSgt Andrus

[bikeaholic]

sarge-you ride a ninja right? talk to freakinout about jets - i think he knows those
setups pretty good-i only fool with the cruisers

[03SSgt]

Yea, its a 04 500. Can't wait till next year, I'm going on the "Atkins Diet" and I'll be "carb free" I'd rather just plug in a power commander and go, instead of all this tweeking

[r409z]

I installed my jet kit today and took pics.....here they are .......

www.geocities.com/scottbri409/Dynojet.html

[Freakinout]

Originally Posted by r409z

I installed my jet kit today and took pics.....here they are .......

www.geocities.com/scottbri409/Dynojet.html

Thats a very complete walkthrough. Thanks a bunch.

[reeB_relliM]

Originally Posted by Freakinout

Thats a very complete walkthrough. Thanks a bunch.

Great step-by-step tutorial, however, I think he should've expressed the importance of thoroughly cleaning and deburring the slide lift hole that he'd drilled (...with the supplied Dynojet drill bit) Any particles get into those carbs, and the story gets really short, really fast!

Probably the most important thing to do, is to take steps to insure cleanliness. Debur any drill shavings and/or tiny fragmented particles that might be hiding in a hidden nook or cranny. Best to use an air hose to blow any loose crap out, then use warm soapy water, then air again to dry (BE CAREFULL NOT TO HIT THE DIAPHRAM WITH COMPRESSED AIR!!)

Then he mentions as follows:

"You will probably have to hold the bottom part with vice grips while you screw out the stock jet."

DO NOT USE VISE GRIPS ON BRASS ANYTHING!!! That's a sure fire way to really screw things up in a hurry. Either a box end or open end wrench will do just fine, but a line wrench would be best for this task.

I really hate to sound like such a critic, as he does list some very helpfull information about this procedure, ..but hey, we all know that there are people out there who wouldn't have even thought about where all those little particles might have went, unless it was stressed in bold print within the instructions, ...hell, some people wouldn't even see it then!!! (Geesh!)

Just my $.02 worth, that's all.

reeB_relliM

[1Adam12]

Here is a picture of a 4 bank carb set up.

[1Adam12]

[BlackEX500A5]

How much do these carb kits cost and where can I get them? also do you need aftermarket exhaust and air filter for this to work properly?

[StinkBug]

My bike was really acting up when I bought it, and after reading through all this I still couldn't get it figured out. At startup it was running really rich, but after a few minutes of riding it would start running really lean, and would actually stall and die out on me. I finally gave in and pulled both carbs and completely rebuilt em. Everything was in good shape and properly adjusted until I got to the floats. Turns out whoever rebuilt the carbs screwed up the levels and both of them were WAY down. to the point that they would barely open the needle valves at all, so basically the bowls weren't filling up and the bike was running out of gas. Fixed the floats and put everything back to spec and she runs awesome now. Hope someone else can get something out of my bad day (bike stalled on the freeway 3 times, and also lost a sparkplug somehow)

Dallas