YZ400 Blaster... Need some help

Well long story short I got a mostly complete and almost ride ready Yamaha Blaster with a 1979 YZ400 motor.... the reason for posting in the Yami dirt bike forum is cause I have some wiring questions about the YZ400 and I don't think too many people in the ATV section have much experience with the YZ's. Anyways, after figuring out that I wasn't getting spark I decided to look at the wiring and it appears that I have either an entire system for a 1999 YZ400F Four Stroke, or the stock harness from the 1979 but a 1999 CDI Ignition Module. I might not have the bike wired up right so I was hoping someone could draw me up a diagram or link me to one, I would greatly appreciate that. I am trying to get the bike set for Busco Beach in the next couple of weeks.

Well long story short I got a mostly complete and almost ride ready Yamaha Blaster with a 1979 YZ400 motor.... the reason for posting in the Yami dirt bike forum is cause I have some wiring questions about the YZ400 and I don't think too many people in the ATV section have much experience with the YZ's. Anyways, after figuring out that I wasn't getting spark I decided to look at the wiring and it appears that I have either an entire system for a 1999 YZ400F Four Stroke, or the stock harness from the 1979 but a 1999 CDI Ignition Module. I might not have the bike wired up right so I was hoping someone could draw me up a diagram or link me to one, I would greatly appreciate that. I am trying to get the bike set for Busco Beach in the next couple of weeks.

I don't have a diagram for you, but the 1979 YZ400 was about as simple an engine and ignition that you could have.

I don't know what all would have to be done to adapt the CDI and other ignition pieces from a '99 four stroke to work on that. The '79 and '99 are about as different as possible. The only similarity is that they both displace about 400cc. Other than that, they have nothing in common.

You need to make sure that the points and condenser are good, and you will need the correct coil for that engine. I believe most of the ignition parts you would need, other than the flywheel and stator, were used on several different models back then. Do a search on eBay and you should be able to find all of the ignition parts you would need.

Actually the YZs didn't have points at that time. I just did a search on E-Bay and found every single part to get the CDI working again. Just use original parts and you will be much happier than trying to cludge something else in there. :smirk:

I don't have a diagram for you, but the 1979 YZ400 was about as simple an engine and ignition that you could have.

I don't know what all would have to be done to adapt the CDI and other ignition pieces from a '99 four stroke to work on that. The '79 and '99 are about as different as possible. The only similarity is that they both displace about 400cc. Other than that, they have nothing in common.

You need to make sure that the points and condenser are good, and you will need the correct coil for that engine. I believe most of the ignition parts you would need, other than the flywheel and stator, were used on several different models back then. Do a search on eBay and you should be able to find all of the ignition parts you would need.

I can't imagine a 400 in a blaster. Would love to see picks. I thought a 250 big bore was pushing it on that chassis, unless this is just a hillshooter. Fun project! Sorry I can't be of help.

Actually the YZs didn't have points at that time. I just did a search on E-Bay and found every single part to get the CDI working again. Just use original parts and you will be much happier than trying to cludge something else in there. :smirk:

I stand corrected.

As long as he has the pieces needed to put the '79 electrical system back to stock, it should be a very simple project. Should only be a few wires from the magneto to the CDI unit and then to the coil and plug boot. Oh, and don't forget the wire(s) to the kill switch.

Hey guys, sorry I havent replied in a while, my email notifications have been bouncing back so I had no idea this thread was still alive. Anyway, heres a link to my photobucket album with some pics. The purple blaster is stock, look at the one with gold front rims: http://s1235.photobucket.com/albums/ff430/stevensj13/

Still no spark :ride:

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