Removing J bike carbs

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Motorcycles, and Kawasakis in general, and EX250s specifically, are known for not always having all their carb settings in perfect order right out of the box. Here's how to take care of that problem.

Start by removing the fairings. Then, once the fairings are out of the way, you get to see all the different things that are still in your way to get at the carbs. There's a lot. Expect at least an hour and a half to get them out.

Remove the gas tank. You can wait until later, but it'll go easier on you if you do it now.

Even with the tank out of the way, you still can't really get the carbs out easily. Go to the right side, bring your #2 phillips, and remove the screw holding the throttle cable plate to the carb. Remove the cables from the carbs. Some find it easier to loosen the cable nuts and detach the cable ends. Measure or mark where they are for when you put them back.

Grab a 10mm and an 8mm socket and, on the right side, remove the bolts holding the coolant tank (optional) to the bike and the bracket where the upper rear bolt mounts the fairing (5mm). Two 8mm-headed bolts hold the coolant tank, and three 10mm-headed bolts hold the brackets. On the left side, pop the idle speed screw out of the bracket and remove the bolts holding the fairing bracket thing out of the way.

They routed the clutch cable through a loop that is part of the coolant reservoir bottle, so it may not be easy to move it out of the way enough to remove the 8mm headed bolt at the bracket.

Now you are getting closer to removing the carbs, but you aren't there yet. Remove the 3 phillips screws holding the battery box and its cover. Remove the battery.

Pull out the foam that the battery was sitting in, and remove the final two phillips screws holding the tray in and the battery tray.

The rail that the gas tank mounts to is held down by four bolts (10mm). There is also a bolt on the right that attaches the airbox to that bracket (5mm). Remove them all and move the bracket out of the way.

Down on the left side of the airbox behind the S tube is the other 5mm bolt that holds the airbox to the frame. Remove it. It's right above the front sprocket but buried in there. It holds a thin piece of metal that guides a tube, which only helps the camouflage. You might want to put a pick-up magnet on it when removing, so you don't drop it into the sprocket cover.

Loosen the 3mm allen bolts that hold the airbox to the inlet side of the carbs and push it as far back as you can. It won't go far. You can remove the air injection tube on the top of the airbox for a couple more mm.

Loosen the two clamps holding the intake boots to the carbs/head and pop the carbs back. Use a screwdriver and remove the left intake boot from the engine. This takes finesse. If you've done it on the old bike, you will notice that it's a bit harder to do it on the new bike. Why? Because you can't remove the carb to airbox boots for extra room.

Remove the choke cable from the carbs. You can do this earlier if you like. Take the slack out of it by manually sliding the mechanism on the carbs.

Remove the vacuum hose from the left carb. Use some more finesse and pull the carbs out of the left side of the bike.

Now you have the carbs in your hands. If you think the gas is new and good, you can just drain the carbs into the tank. Otherwise, use a correct container. You need that 3mm allen key again.

Now you just need to remove the phillips screws holding the float bowls to the carb bodies and drill out the mixture screw protective caps. Then you can make all the adjustments you need to the carbs.

Make sure both float heights are set to 17mm. Mixture screws on this bike were set to 1.5 to 2 turns out for the left cylinder and 2.5 to 3 turns out for the right from the factory. Set them both to 2.5 turns.

Put everything back together (much faster than taking it off). When re-assembling, do the airbox side first, and have the battery tray out and the airbox unbolted from the frame. Two bolts, one lower left front, one upper right rear, 4mm hex heads. The airbox can move about 3/4".

Set the petcock to prime for the first start. Don't forget to switch back to the on position; you don't need a flooded engine in the near future.