my bike is failing on hydrocarbons. Do I need to re-jet. I have never opened up a carb before, will I need a jet kit or what? Any tips or tricks to help me pass?

 

You should be able to wind in the pilot screws too lean it up.

 

Before cracking the carbs, here's a question: Do you have an aftermarket exhaust?

 

Dude if you're too rich at IDLE rejetting won't do ****. Rejetting doesn't replace the PILOT jet it replaces the MAIN jet. Anything occuring below ~6k is due to the pilot jet. Turn your fuel screws in a bit and lean it out. See what happens.

 

I'm sorry, I am so carburetor retarded it hurts, it really does. I am running stock filter and exhaust right now

The sheet reads. . .

Hydrocarbons 2300 PPM (parts per million)
Hydrocarbon limit 1800 PPM

Carbon Monoxide .21
Carbon Monoxide limit 5.50

I thought my bike was really rich at idle because of the high amount of hydrocarbons, but my buddy said with my carbon monoxide being so low, he is thinking I have a lean misfire at idle.

Do I have to rip apart the carbs to adjust the idle mixture screw?

 

where do you live that emission tests motorcycles?

sorry for nothing usefull to add.

 

im in phoenix az. They were thinking about dropping emissions for bikes several months back, haven't heard anything since then. . . EFF

 

No you don't have to rip the carbs apart to get to the pilot scres. They're right on the bottom of the carbs, and should be relatively easy to access without removing everything.

First, a quick lesson on your carbs:

Alright so the concept goes like this. The motor creates a vaccum by first expulsing exhaust out the exhuast valve. The exhaust valve closes, and the piston goes up, expanding the cylinder creating a void area for airto take up. When the intake valve opens, it pulls air in. The air gets pulled in from the carbs, which has fuel mixed in with it. The intake valve closes, the piston compressors, spark ignites generating power... and you then exhaust and rinse and repeat. Basic principle of a motor simplified.

There are two jets in the bike, which let a certain amount of fuel through when a certain amount of vaccum is induced. One jet is PILOT, and handles (on our bike) everything below 6k. The MAIN jet kicks in around 6k and takes off from there. They are vaccum operated, so when the engine pulls air through the carbs, fuel gets pulled through them and mixed with the incoming air. Very simple explenation of a far more complex concept. For now, you've got the jist.

They are two seperate "circuits" per say. If you've got problems below 6k, look into pilot jets. If you've got problems above 6k, look into main jets.

https://cbrforum.com/forum/f2-tech-93/carburetor-cleaning-tuning-101-a-96888/

Read that, even if you aren't taking apart the carbs. It'll help you understand everything.

What I would do if I were you:

To my understanding with the DEQ, you've got as many tries as you want and you only pay when you pass. So get down there with the ability to adjust your carbs, and give it a go! Also it may not be a bad idea to put new spark plugs in just to ensure you're getting the best spark possible. The description I have below should walk you through everything, and let you try all the reasonable adjustments you could easily make yourself. You aught to be able to get the adjustment right doing the below:

Start by Removing your tail plastics and side plastics before going to the DMV. It should still be legally drivable at this point. Leave the seat on. Drive to the DEQ, with the nescessary tools (described below) in a back pack.



Okay, that picture is from the carb cleaning tutorial. It's of the BOTTOM of your carbs, which again should be easily accesible with the plastics removed. Before you go to the DMV make sure you take a look at the bottom of the carbs, and get a slight bearing on where you are. In that diagram, the red arrows point to the screws which hold the FLOAT BOWLS in place. Directly inbetween them, you'll notice a round grey dot. Notice how each carb has one, and the far left one is slotted. They don't come slotted, but you can dremel a slot into them to make them easily adjustable. You can also get a special tool for adjusting them, and the tool also comes with the dynojet stage I kit. CHECK YOUR CARBS AS THIS MAY HAVE ALREADY BEEN DONE FOR YOU! It's a common modification to perform on the carbs!

If they aren't already slotted, you will ideally find the tool. Perhaps ask a local shop concerning purchase or location. It should be cheap. I can sell you mine for cheap if you want, $10 with shipping. I'm not using it as mine are slotted. I doubt you'll be able to get a dremel in there to properly slot the fuel adjustors without removing the carbs, but if you want to try feel free to do so CAREFULLY!

ANYWAYS, get in there with whichever tool, and then if you want to LEAN your mixture turn right (right goes in) or left to RICHEN (left, backs out). First take your fuel mixture screws in a 1/4 turn, and see what your numbers are then when run. Compare them to the prior numbers and see which direction you results are going. If they're worse (higher), try richening the mixture instead by undoing the 1/4 turn in, and then go a 1/4 turn out from there. If the initil 1/4 turn in made things better but not good enough, try leaning it out some more by going yet another 1/4 turn in. An easy way to see how far you're turning is to draw on the tool with a red sharpy. Then eyeball 90 degrees for your turn (should be easy enough) and that's a 1/4 turn.


Hopefully that helps. You should be able to get the ideal mixture. This all should be a relatively easy and simply process. It'll impress anyone who sees you doing it too, as they'll think you're a gear head!

 

holy sh*T that was super helpful. I was thinking of taking my bike to a shop to do the work, but I might just wait until school is out and tackle this myself.

 

Glad I could help. Seriously it should only take you a few hours AT MOST, given a 20 minute wait for each DEQ test run. If you're lucky you'll get it in the first hour.