Coils for Maxim 400

Good day, found this forum while looking for parts. What a great resource.

I have an 84 maxim 400, which I bought, like new, for $600 thirty years ago when I was 17.
I have had it insured and running every year except for the last two.
It started and ran then quit as I was getting spark on only one side.
Long story short it looks like I need new coils and am having a hard time finding them. With the electronic ignition it looks like I need 3 Ohm coils.
I've looked at Mikes XS and Fort nine but no luck.
Does someone have an Emgo part number or a source? Preferably in Canada.

Thank you!

https://www.partsnmore.com/parts/yamaha/xs400/?filters[category]=electrical&filters[fitting]=custom

Whacky priced though, the stud sticking out is likely the reason. You could buy coils with no stud and figure a way to mount them to save like $40. The 4 ohm thing doesn't hurt, you just don't want to go under 3, the lower you go the more volts the switching transistor in the electronics has to hold back and it will begin to overheat to fail. 3 ohm coils are a holdover from the days of points, the limit stopped points burning too quick.

Look closer, often the plug wire connection makes coil appear to be bad. I've drilled into one piece coil and wire on Honda four to change the wire only and suddenly coils then work fine again. Gluing the wires back in was a bit messy but saved at least that $75.

amc49 said:

https://www.partsnmore.com/parts/yamaha/xs400/?filters[category]=electrical&filters[fitting]=custom

Whacky priced though, the stud sticking out is likely the reason. You could buy coils with no stud and figure a way to mount them to save like $40. The 4 ohm thing doesn't hurt, you just don't want to go under 3, the lower you go the more volts the switching transistor in the electronics has to hold back and it will begin to overheat to fail. 3 ohm coils are a holdover from the days of points, the limit stopped points burning too quick.

Click to expand...

Thank you ACM. My thinking was that a higher resistance would hurt the electronics. Thanks for the reassurance that it is opposite.

amc49 said:

Look closer, often the plug wire connection makes coil appear to be bad. I've drilled into one piece coil and wire on Honda four to change the wire only and suddenly coils then work fine again. Gluing the wires back in was a bit messy but saved at least that $75.

Click to expand...

Thanks a lot. I was reading about that but was measuring the coil inputs, with no leads and had very large differences between the two. I'm learning as I go along and appreciate the input. I have been riding this bike for over thirty years and have only had to do chain, sprockets, brakes and cables. I wish I knew the mileage as the instruments grenaded about 15 years ago...

The points xs400 bikes used the 4 ohm coils. The 80-82 sohc and the 82-84 dohc have the 3 ohm ones. You can use the 80-82 sohc coils on the dohc bikes as they are the same ones. Make sure to check the secondary as well as the primary. Which are (p)3 and (s)8.6 These type coils are easy to replace wires and caps just use copper core wire and the correct ohm cap to go with what type plug your using. Search oem part numbers and you should find lots of them new and used.
3Y6-82310-60-00

Great stuff. Thank you Chris.

So after further trouble shooting it now looks like it is a bad pickup coil.
I read 120 ohms on one and nothing on the other. I can't find a break in the wires so will have to try to find some....