Coil and resistor

[on2wheels]

I am missing a resistor for my 77 RD400 restoration project. Is the updated coil that negates the use of resistor a good idea? If yes, where can I buy it in US so I don't have to buy it from Yambits in UK?.
I usually like to stay with the original when restoring a bike but since I'm missing the resistor, I'm thinking maybe I should replace the coil's with built-in resistor.
Thanks.

[m in sc]

JUST USE 3 OHM COILS, BYPASS THE RESISTORS. 

[Dvsrd]

JUST USE 3 OHM COILS, BYPASS THE RESISTORS. 

Will that work with, say a 55/60W H4 headlight?
Reason for me asking, is that using 3 Ohm car coils on my RD350 caused misfiring at high revs when using H4 headlight. It appeared to me that the charging system was overwhelmed, causing the voltage to drop enough to cause misfiring.

[m in sc]

car coils are much larger windings. use a 3 ohm motorcycle coil. also verify charging system. years ago o ran a halogen, Allison car ignition and car coils and it was fine.  but that was many years ago