Topic: 1974cb750k 3ohm to 5ohm coil

[mr.brandon]

So, I have a 1974 cb750k and have kind of always had a problem with the 3 ohm coils burning up on me as, the coils are mounted below my oil tank ('74 engine on bobber frame) I am going to purchase a new set of coils tomorrow and am thinking that I should go with 5 ohm. I believe that's what the later models ran rather than thev3 ohm. I dovrealizevthat thev3 have less resistance and provide better spark but, the heat that they (the 3 ohm coils) are producing, seems to be burning them up prematurely. Does anyone have any input and or experience on running the 5 ohm instead of the 3 on earlier 750k's? Also, I run a points system not electronic.

[Don R]

They came new with 5 ohm coils under the tank. Vintage cb750 has some stock replacement coils that are known to work well. Avoid the cheap china made stuff and try to not leave the key on and motor not running.

[scottly]

Stock coils are 5 ohm.

[mr.brandon]

Sorry for the reiterating,.. I was under the impression that the earlier models stock was 3 ohm and only the later had 5 ohm for stock?

[scottly]

Nope, the stock coils were always 5 ohm.

[mr.brandon]

Appreciate it. One day I will get on here with some talk about actually riding the bike!  Thanks for the knowledge ,though, gang!