Yamaha RD250/350/400cc

By RD Chinoy

Introduction:

It gives us great pleasure that you have decided to try out this system on your bike. This kit is something that I spent many years working on it stemmed from problems I was having with my Bike.  Which is a Yamaha RD350B 1984modell (1974 for you guys). This isn’t a big commercial product. Nor am I a big manufacturer. Just a simple guy who likes to make things with his hands.

The kit as you see it now is a far cry from the early kits we shipped years ago. We pride ourselves on the constant effort to improve the kit. The separate CDI is the third major revision of our CDI kit. And we are actively working on the forth and final revision for the same kit. Which will be a Digital Programmable CDI with a LCD Speedo and RPM counter. You will be able to upgrade your existing kit to a Digital CDI shortly for a small fee.

Kit Contents:

Base Kit :

•  Brass Coil Plate with Lighting / charging, source and pulsar coils

• Magnetic Drum.

• Two New Technology combo HT Ignition Coils with C.D.I OR Separate CDI and HT coils.

• Rectifier & Regulator

Options: 

• New Switch Cluster Left (Turn/PO/Hi-Lo/Horn etc.)

• Flasher (Required for Indicators, requires a batt. to work)

• 3x1 Instrument Cluster Bulb Holder (high beam/neutral/turn)

•  Harness (Complete New Yamaha Harness, everything just plugs in )

• Ignition Switch with Two keys (For R5/RD200/RD250/RD350 etc)  Note mounting clamps may not match. But you have to use our switch. You can switch the insides with the older switch though. 

• Clutch Lever Yoke and Clutch Leaver.

• Head Light Bulb holder (two types).

• Indicator Buzzer (If available).

• Fuse Box for DC Bat.

Installing the Kit:

The install is really quite simple. But its best to get it professionally installed.

 First strip bare all the old stuff off your crank end. Like so:

Then Install the Brass Plate make sure the pulsar is located at the 6 O’clock position. Unless this is done right the bike will not start. Feel free to file the slots out in either direction to get the timing right we only give you an estimation of where the bike will run best:

3.      Then install the drum over the crank end. Make sure to use the woodruff locating key. Make sure your key fits in the slot the cam on the drum has. It should be a really tight fit. Route the blue neutral switch wire from under the brass plate. Also check to make sure the wires are not pinched between the plate and engine casing.

4.      Now hook up the CDI harness to the two bullet connectors. Coming off the brass coil plate. On is source power (Black & Red) the other is pulsar (White blue) this is all that’s required to make the bike run. 

5.      Do not connect up the Black and white wire on the CDI harness to anything till you have the bike running. This is the same as the source power in and the only thing it should hook up to is a kill switch by no means should it touch any DC voltage or join any other wire as this would fry the CDI. Once you have the bike running the black&white wire on the CDI harness can be hooked up to the main harness which has a b&w bullet connector.

6.      The HT Coils have a Green wire and a Black and Red. Green is earth and black and red is power in. Make sure the HT Coils are earthed to the frame of the bike by bolting them down tight scrape off any paint so there is good metal to metal contact, between the metal part of the HT coils and the body earth.

7.      We repeat do not hook up anything else except the CDI and HT coils till you get the bike running. Once its running. You can start installing the other options.

Understanding the color codes:

Brass Coil Plate:

·        Black+Red: Source power to HT Coils. (Bullet Female) 280Ohms / 12+ Volts a/c on kick over. Connects to CDI harness.

·        White + Green: Pulsar Signal to CDI (Bullet Female) 80 Ohms / 2 Volts a/c on kick over. Connects to CDI harness

·        Yellow+Red: Source power Head Light & RR Unit (A/C) 1 Ohms

·        White: Source power A/C to RR for Conversion to DC 1 Ohms

·        Blue: To Neutral switch on White Triangular plastic

·        Black: Earth.

HT Coils:

       Green: Earth must be grounded to chassis connects to the 2 greens off CDI harness.

       Black & Red: Source power in. Connects to CDI Harness.

CDI  Box/Harness:

Green White:   Pulsar signal (to Bras coil plate)
Black Red:       Source power (to Brass Coil Plate)
3x Green:        Earths one to Body 2 to HT Coils
2x Black Yellow: Source Power to HT Coils
Black White:   Same as source in only to be connected to Ground to kill engine (Hooks up to a black and white wire on the Main Harness)

Integrated CDI: These use 3 Y Cables that are White, Red, and Black and white. These are used to split the Source signal from brass plate and pulsar signal to the two HT/CDI units.

Rectifier & Regulator:

       Yellow+White: A/C power for Head light.

       White+Red:                 A/C in off coil plate

       Red:                             DC out 13.5-14.5 Volts. Do not load without a batt. Hooked up.

       Black or B&W             Earth.

We have labeled the complete harness. Simply read and plug in required component.

FAQ

Kits where both CDI systems have been supplied. Which do I use.

We recommend you use the newer separate CDI system and keep the combo units as a back up.

Danger of blowing up CDI.

The CDI will be damaged if

1. You use your stock Ign s/w and not the one supplied with the bike.
2. DC Voltage of any kind comes in contact with the CDI harness or CDI
3. The HT Coils are not grounded to the frame of the bike. They need to be grounded firmly metal to metal with a Nut.
4. The HT coil lead is help too far away from the engine preventing a spark from forming.

Yamaha 100 Watt C.D.I. Kit

• Note for Customers of the New CDI.
• Preparing for Install.
• Installing the Coil Plate.
• Clearances
• Mounting the HT Coils
• Understanding the Harness.
• First check for spark.
• Warning for Basic Kit Customers.
• Circuit Diagram.
• Word Document  (The old Install Document with some notes)
• Timing Procedure.  (Try and get this done once at least)
• Trouble Shooting.

Note: This by no means cover all the issues that are bound to crop up during your install. If there are any issues not covered here or you just want to discuss how your installation is going please feel free to mail me no matter how small the issue.

New Separate CDI customers:

If you have one of the newer CDI systems. Please mail me.

The new CDI system is totally different from the CDI covered below. I will be setting up a separate install page for it shortly. The CDI wires are different the Mag drum is different. The coils are different.. And the clearances and mounting screws are different. Check here for New Kit Page. We recommend you read thru this and then move onto the new kit page.

Preparing for Install

First see that you have received all the parts ordered.

Read this document and the other documents. Develop a plan of action for the install.

Which should be to first install the CDI kit start bike and then move onto installing the harness.

Step 1.

Make sure you remove all the old components from the Crank end. Leaving it bare as shown in picture.

Remove everything from Crank End.

Installing the Coil Plate.

It is important to get this step right to ensure the wires are not pinched or pressed up against the engine casing. Which could result in a short or pinch the wires open.

Route wires exactly as shown

On casing. Note route for Neutral wire and other wires..

With the plate screwed down shake the harness the wires you see in the picture should move. i.e. make sure they are not pinched between the coil plate and engine casing or crank lip. Now all you need to do is glue the lock key into the crank end and mount up the magnet. If its a high RPM motor. Tighten down bolt to 35 pounds with loclite. Also check this frequently. Likewise for the screws that hold down the Brass Plate.

Mag Drum Clearances:

The Kit has been designed with measurement tolerances of 0.5 mm so it is highly unlikely that you should run into any problems. But it is still important that the Drum be installed safely. And getting it to mount with the key is probably the toughest job in the install.  Each gap and clearance in the system has a logic and reason behind it. If in doubt please ask a question. (Pictures below taken without the Key.).  

Clearance between the Mag Drum lip and plate should be 6-7mm in the older kits.

In the newer kits that use the more powerful larger cups this clearance is .5mm and the screws are counter sunk to avoid contact.

Installed on a RD400

Mounting the HT Coils:

A frequent question is where do I Install the HT Coils. Well we provide a very long lea wire so you can install it where ever you want. People install it in various places from the tool box to the sides of the frame under the tank. I prefer running my coils in the stock position. The little stubs need to be filed off and the coils installed as shown in the picture. Be careful not to make it to tight or the plastic mounting will brake. The coils support each other. The most critical issue is making sure that the Ground makes good contact with the Frame. For this to happen you need to file the paint and any other foreign material on the frame till you see the shinny metal surface. The earth can then be mounted with a nut and bolt. Its also ok to cut the Earth wire and solder on a longer lead if you want to. A sure sign that your earth not making contact is when the bike starts ok but when you rev it past 5000 RPM it starts to backfire.

Note: The Units shown in the Picture above are the old CDI/HT coil combo units. If you have the new kit. You do not install these. You install the two separate HT coils. With the Separate CDI unit and the CDI harness. Pictured below

Understanding the Harness.

Tail Section

Note: You should use a fuse between Batt+ and Battery.

Coil Plate Section

Rectifier Regulator Section

Head Section

Step Check for Spark

Note:

Before you try to install the harness. We would strongly recommend that you check to see if the bike runs, with the C.D.I kit. This is very simple.

Install only the very basic components of the kit. In this order.

First Coil Plate and Mag. Drum

Then the HT Coils.

Then simply join the Coil plate to the HT coils with the two Y cable provided. One Y caries the pulsar signal telling the C.D.I when to fire and the other carries the power to the HT coils. The third Y cable is the Black&White Cable which hooks up to your harness. Dont connect this one just yet.

Note: The picture above is off the Older CDI Combo Kit. Do not use them even if we sent you a set with your kit. Keep them as an emergency backup. Instead install your Separate CDI box and Coils.

Once the bike is running you can proceed to wire in the rest of the options.

Hope this helps. Mail me if you need any further information. 

The reason we keep the Y cables separate from the harness is to allow people who buy the basic kit to get up and running with out any complications.

The reason why we don't have a whole lot of fuses. Is because our system runs on AC. A system that runs its Ignition, Lighting, and everything on DC needs fuses. On our system we do have a fuse between the bat. and the harness. No fuses are required beyond this. Because if there is a short the bike simply wont start.

This is how it looks installed on the bike note first the mag drum then the large nut then the washer then the bolt to hold it all down. Or you can do it any other way just remember to use a washer and make sure the bolt is secured. 

CIRCUIT DIAGRAM

Note:  

Click on the image above to open it full size (Clearer). Use the full size image if your saving it to your hard disk or printing it.

Trouble Shooting:

Note: No matter how sure you are that there is something wrong with the kit. don't panic. The kit has been sold around the world there are tons of people running the kit with no problems what so ever. Yes the first five kits did have some problems which where sorted out. Every now and then when the kit was installed on a new model some issues would crop up which required revisions to the kit. But by the time your reading this the kit has already sold to over 1000 RD owners. So it is highly unlikely that the problem your facing is a Bug in the system. I have noted some of the common problems and questions people run into while installing the kit. This by no means can cover all the possible issues so feel free to mail in your questions. Just don't go "There is something drastically wrong with the kit it cant be installed properly on a RD.  Mail in your questions / problems and we will try our best to sort them out.

• I followed your recommendations of hooking up just the Basic kit and 2 Y cables I'm not getting a Spark.
  
  Take a Multi Meter and check the readings between the White/Green wire and Ground. Take the reading at the connection just before you plug it into the HT Coil White wire. You should get a reading of 82 W. If you get no reading then there is a loose contact between the point where you are checking and the Pulsar. If you get a shorted reading that means that the wire is touching ground somewhere. Likewise you need to check the readings for the Red Y cable which is connected to the red and black on the Source coil. You should get a reading of of 280 W. Same issues here a short means the wire is shorted to ground no reading means a loose contact. Look for the loose contact at the various connectors. And check the wiring and Y cable separately with a multi meter. If you cant locate the problem you will need to pull out the Coil plate from the bike and check the wires.
  Another reason why you are not getting a spark could be if the Red Female bullet connector is grounded or connected to the Harness with the Black/White Y cable and this is being grounded either by the kill switch or the Ignition switch. Which is why we don't recommend hooking up this wire till after initial testing. Ok so now we know there is no short and that the coils are ok. We now need to chk if the coils are touching the magnet or too far away from the magnet. For this we switch the mm to measure a/c current. With the plugs out give the bike a few swift kicks. You should see +12 Volts from the source coil and +2 Volts from the pulsar.

• Only one engine is running. 
  If one engine is running then it means the source coil is producing power all right, And the pulsar is also working because its sending a fire signal. The only issue could be that there is a loose contact with one of the Y cables. Or that the HT coil is not working. Use a multi meter to check for a loose connection or shorted wire. 

• My head light is not working.
  If you see the picture above showing the reverse of the coil plate. You will see that a single red wire from the lighting coils is connected to the Yellow and white wire. This sometime comes loose. We have designed it in such a way that it comes loose if pulled. Better the wire separates here than braking the wire from the lighting coil and ruining the coils. Check the White and yellow wires on the coil harness and ground to see for an open or short. If this is OK you will need to chk for power in various  other points i.e. at the switch cluster.
• I'm not getting a spark and when I turn the magnet with my hand the long source coil is touching the magnetic drum. I need a new brass plate. (reported by only one customer)
  The only reason we use the mush more costly Brass for the plates is because no matter where in the world you are its easy to work with. The solution to your problem is easy. Simply loosen the the screws holding down the long source coil and move the coil to the right or left as needed and tighten down. You may need to file the legs the long source coils sit on. Reinstall and your problem should be sorted.
• The wires are getting pinched.  And the plate is not sitting flat.
  You have to get the wires routed exactly as shown in the pictures above if you do it will work fine.
• I cant get the magnetic drum onto the crank end. Do I need to file my Lock
  First check that the key lock unit is standard size and slides freely in the slot / keyway of the mag drum. Some people find it easier to install the drum if the half moon lock is stuck into the crank end with super glue. Some find it easy to do without sticking the half moon lock to the crank end. NO you dont need to file your lock. Because the Drum will ride up the crank end based on the way the neck is machined and has very little to do with your lock or the keyway.
• I'm getting very low voltage at the Horn and indicators.
  The kit outputs a/c. This a/c is good to power your HT Coils with a nice strong spark. And even your headlights. It is not intended to power you D/c applications like Horn / Indicators etc. for this you need a standard batt. Or you need to get an a/c horn and a/c flasher and reroute a/c to these options.
  

Lastly please sign up on our BBS and mail us to enable you access to the CDI forum.

New Kit Page