Building an Adjustable/Tune able CDI

[best]

Hey Tim, Rubbersalt is/was active on other forums but has not been on here since Nov 2016. The DT200 has a better curve than the Blaster, but requires a different pickup. No, it does not require a battery for the ignition but we found we needed a battery for the powervalve controller. I did buy an adjustable CDI circuit board for powered bicycles and had great results with it. Plugged in timing advance in the mid-range and retard for the pipe rpm. I'd like to do more but not enough time at the moment.

Look at Jaguar's website for info on building your own adjustable CDI. Here is a diagram for a simple coil pick-up CDI:

Here is another similar diagram:

Similar to previous circuit. These fire directly from the coil, don't use a trigger device. There are problems with timing accuracy over temperature

Here is what you are trying to achieve with a piped 2 stroke ignition curve:

 

[timstoys]

Glad to see you're still here. And it looks like I'll be digging thru my DT200 stuff. I bought a complete DT200 engine with a bad top end I just need to find the pieces I'll need to convert it over. I don't want to take the time right now to build my own and I believe Yamaha parts will be more reliable long term. Really don't want to by 50 mils from home and be dead. Any chance you have a wiring diagram for the DT200? I found some online but none with the correct number of wires compared to mine. Mine has 7 wires and all are old school bullet connectors.

 

[timstoys]

Oops. After looking again I found the CDI, Harness, stator and flywheel with the rest of my DT200 parts. Looks to me like if I install the DT200 stator, flywheel, and CDI all I need to do is hook the orange wire to the coil and it should run.

 

[best]

Yes, that will do it. My son built the DT200 powered Blaster. We had no wiring diagrams, he just transferred the wiring over from the bike to the quad. I'd appreciate prints if you have any.

 

[timstoys]

Easiest way for me is posting the link. After hours of searching I found somewhere that Yamaha puts the wiring diagram in the owners manuals. Then found that Yamaha Au. has PDFs on their site for free download After more searching I found that the 1988 DT200 has the wiring diagram. Here's the direct link.

https://www.yamahaownershandbook.com.au/lib/download.php?f=2YY-28199-70.pdf

 

[Rubbersalt]

It's been a bit since I've looked at this post. I've got to rebuild my blaster motor(sucked sand at the dunes), then get back to testing. I've got several protypes for this currently. The Tecate CDI is doing very well. It was used in a Race recently and the machine took first.

 

[Slydog]

It's been a bit since I've looked at this post. I've got to rebuild my blaster motor(sucked sand at the dunes), then get back to testing. I've got several protypes for this currently. The Tecate CDI is doing very well. It was used in a Race recently and the machine took first.

That's pretty interesting

 

[79 bronco]

Awesome!

 

[timstoys]

I'm still very interested. Keep us posted on when a Blaster unit will be available.

 

[Rubbersalt]

Looking to send out a few prototypes for select riders to test. We should have some news before 7-25-22. 6 years since the first post on this. Wow - I'm a slacker lol.

I did read through all the comments and this thread a few minutes ago. The Tecate CDI was shrunk down considerably before being sold. People have had a lot of custom request on the housings too. Many just have the owners name or number on it. There are a few special ones I've done up. I do enjoy making them stand out!

 

[timstoys]

Damn I thought this thread alerted me when someone posted. I'm still interested if it's not to late.

 

[Cheese98]

I'm very interested!

 

[Rubbersalt]

I just ponied up the cash to get some early production circuits professionally made. I've got 25 selectable curves. Oem blaster is included in the mix

I have solder all the rebate stuff. Incredibly time consuming. These will have 90% done by a machine for me

There's still work to be done. These are for the 88-02 blaster btw

 

[timstoys]

I'm ready for one. How much are we looking at? If they need assembly I can do that I've been building and running Megasquirt for 20+ years.

 

[Rubbersalt]

Turns out people have chicken legs around here lol. I was the only 1 strong enough to kick over my blaster to start it.... After changing a resistor, everyone could start it, but that caused problems. Went back to the drawing board twice since then. I've got simulations now. Currently, I'm waiting for more components to show up.

On one end of the spectrum, it's easy to start. On the other end, when it revved out to 12k RPM (Yes, i reached 12k in neutral), too much voltage is going to through the trigger circuit. Leaving it as is... MIGHT burn up. Upping the resistance will make it hard to start. Building another prototype as I type. Tomorrow, I'll have more news

Fortunately all the CDIs I had made are not useless. I can remove the adjustability and make them have a single fixed curve. I'll worry about those ones later

..Back to the 12k RPM. That actually surprised me. I didn't think the OEM coil would keep up. I don't know why it didn't go past 12k rpm. It was as if the motor hit a wall. Could have been fuel, motor (67mm wiseco/stock ports/head/pwk 28/fmf fatty/vf4), or coil. But either way, 12k is pretty respectable lol

 

[KaiCor]

Easiest way for me is posting the link. After hours of searching I found somewhere that Yamaha puts the wiring diagram in the owners manuals. Then found that Yamaha Au. has PDFs on their site for free download After more searching I found that the 1988 DT200 has the wiring diagram. Here's the direct link.

https://www.yamahaownershandbook.com.au/lib/download.php?f=2YY-28199-70.pdf

I'm interested in this wiring diagram, but the link no longer opens. In fact, the site yamahaownershandbook.com.au has stopped working. Could someone please tell me where I can find a similar wiring diagram?

 

[KaiCor]

Turns out people have chicken legs around here lol. I was the only 1 strong enough to kick over my blaster to start it.... After changing a resistor, everyone could start it, but that caused problems. Went back to the drawing board twice since then. I've got simulations now. Currently, I'm waiting for more components to show up.

On one end of the spectrum, it's easy to start. On the other end, when it revved out to 12k RPM (Yes, i reached 12k in neutral), too much voltage is going to through the trigger circuit. Leaving it as is... MIGHT burn up. Upping the resistance will make it hard to start. Building another prototype as I type. Tomorrow, I'll have more news

Fortunately all the CDIs I had made are not useless. I can remove the adjustability and make them have a single fixed curve. I'll worry about those ones later

..Back to the 12k RPM. That actually surprised me. I didn't think the OEM coil would keep up. I don't know why it didn't go past 12k rpm. It was as if the motor hit a wall. Could have been fuel, motor (67mm wiseco/stock ports/head/pwk 28/fmf fatty/vf4), or coil. But either way, 12k is pretty respectable lol

12k rpm is a huge number. You didn't burn anything out? I'm a little wary of giving such a large workload.

 

[Rubbersalt]

12k rpm is a huge number. You didn't burn anything out? I'm a little wary of giving such a large workload.

I've refined it further. I havn't checked Peak RPM on the new refinement. I'll be refining them further too

The other model was apparently to hard for the nephew/his friends to start. I havn't checked peak RPM yet... But it's definitely up there! I'll be shipping a few test units out to a few people very very soon


This is a good portion of my test/prototypes.