Tuning and Modifications:  Cleaning the Fuel Rail / How To Fix Your Choking Problems
This article is to address the choking problems of the DiTechs...  Many have asked how to clean the injectors and want to know what the fixes are for the problem.  If you haven't read the choking DiTech article, I suggest you read it first.  CLICK HERE

A fix kit HAS been issued by Aprilia, if you have a newer Ditech and it is under warranty DO NOT ALTER YOUR SCOOTER... TAKE IT TO YOUR DEALER AND HAVE THEM PERFORM THIS FIX FOR YOU.  IT IS COVERED UNDER YOUR WARRANTY:

This service bulletin was issued by Aprilia 06/08/2005...

Dear Dealer. in case excessive condensate is generated in the compressed air system, it is possible to install the condensate drain kit (no. 8276090). This change drains the compressed air tank on fuel-rail upon every vehicle switch-off, thus preventing condensate to be accumulated for example in case of frequent start-ups, use of the vehicle for short trips and at low speed

Talk to your dealer about this if you have these problems and also print out this .pdf and bring it with you, see it/download it HERE.

Start by removing the lower farings that are located near your ankles.  There are 2 panels, one on each side.
Once the panels are off you will be able to get to your fuel rail.  In this photo I have removed other panels, but you need only remove the 2 stated above.
Before you remove the fuel injector, you must disconnect the fuel lines.  Start by removing the T-20 torx bolt out of the clamp that holds the fuel lines in.  Fuel will not come out of the intake line (the one with the spring on it), but fuel will dump out of the return line.
Either drain it into a gas can or plug the line after you disconnect it.
This is an illustration of the air line.  You can either disconnect the line here at the injector or at the compressor.  If you intend on performing the air line dryer modification, I suggest you just disconnect the line at the compressor.
To remove the fuel rail, remove the two 8mm hex bolts as shown in the picture.  After these are removed, simply pull the fuel rail off.  There is an o-ring that holds it on so it takes a little tugging to remove it.
Once you have the fuel rail off, remove all bolts in it and completely disassemble the entire fuel rail...  TAKE NOTE AS TO WHERE EACH O-RING BELONGS!!!  Clean everything well with clean fuel.
After everything is thoroughly cleaned up, re-assemble all the parts EXACTLY the same as it was.  Place a small amount of 2-stroke oil on all the o-rings to lubricate them for easier assembly.  This also helps to seal properly and helps protect the rubber.

Re-attach the fuel rail to the motor and re-connect all your lines and you are done.

If you wish to perform the in-line dryer modification, continue on.

Below I show how to install the dryer and a pressure gauge.  The gauge is not required, but it is nice to have.  If you don't wish to install the gauge, then you won't need the "T" fitting and you will will simply cut the hose and put the filter in place.

Fittings and hose are 5/16 diameter.  Hose clamps will also be needed.  Purchase the smallest dryer you can find...  Mine is about an inch in diameter and is about 4-5 inches tall.

Here is a quick sketch of what you are going to do.  If you are going to install a pressure gauge you will need some extra hose to do this mod.  Make sure you buy HIGH PRESSURE INJECTION HOSE!!!  There are several ratings of hoses.  Injector hose is usually the most expensive, but that is for a reason.  Don't cheap out and get the wrong hose.  Most auto parts stores carry this hose.
Most hardware stores carry the filter/dryer, pressure gauge, hose clamps and brass fittings.  Be sure to remove the filter that hangs in the center of the bowl. If it is left in it alters the pressure of the air.  Also a very small amount of oil on it makes it clog easily and slow air flow way down.  The filter is not needed to remove the water from the line.

When connecting the dryer, make sure you have the air flow going in the right direction.  There is usually an arrow indicating which direction air flow should go.

Assemble the hoses as you want it to look and then connect the apparatus to the injector and the compressor.

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