Ok 1st off Merry Xmas to everyone! On to it then...i have searched the forum and google with no luck at all. I picked up a 99 f4 this summer and am spending the winter months here in Upstate NY upgrading anything that seems to be an issue ( like the CCT and R/R ) and I keep coming across posts on various cbr forums of low voltage readings coming from the 10 amp power relay. Some posters are claiming a drop to 7 volts while the bike is running and the coils are on this circuit ( the black/white wire ). That sucks..so i've been trying to find any info regarding beefing up the ignition circuit. Let me digress..my mistress is a 96' YZF750SP and I have a 30 amp relay switching direct battery power to the coils. No HP gain but she runs so smooth and efficiently(sp?) that i'd like to do the same with the f4 but I can't seem to find anyone that has tried/done it at all, except where stick coils have been retrofitted to an older coil and HT lead setup (like my yzf)..so does anyone have any info on this or am I the guinea pig here?

 

First of all, congrats on your F4.. One of the best bikes put out by Honda IMO.

Before doing anything can you confirm that your bike is doing anything "wrong?"
My old F4 had a slight stutter at stop lights when it was really hot out in traffic, but it was nowhere as bad as some others had I'd. I replaced the stock R/R with the revised Honda finned one just in case, although the OEM tested just fine. To combat the lower voltage at idle issue, I installed an LED taillight (which I still have sitting in the box lol if you need one), hotbodies LED flushmounts, and a DDMI HID kit. With all of that installed, my hot idle stutter was totally gone.. Ironically, I sold her about a month after that because I fell in love my F4i

Every bike is different, and what works for be person doesn't work for all.. Best of luck with it.

T

 

Thanks turbulenz, she is pretty cool and just around 100 lbs. lighter than my yzf to boot. Anywho..no real problems at all so far but I did notice that sometimes she idles a bit rough. I've been thru the carbs, they're clean, air filter is clean. I haven't tested for a drop yet but just looking at the size and length of the wires from front to back and then front again has got me wondering if I can power the stick coils directly from the battery. I do have LED signals and taillight so I know that will lighten the load on the system but I really want to remove the fan and the coils and power them straight from the battery via a dedicated 12v 30 amp relay for just that. The wiring system, with everything running through the ICM is definitely more advanced than my yzf so it's not as seemingly straight foward. Just reaching out to see if anyone has tried this. Thanx

 

this sounds along the lines of what you are thinking.. this guy hasnt been on in about 6 months... be careful... do at your own risk.. personally I tried to find less extreme ways of dealing with the issue to fix it.. but to each his or her own..

good luck

https://cbrforum.com/forum/cbr-600f4...months-131089/

 

Thanks again, I deff don't want to fry anything so I'm doing my homework before I dive in on this. It's super easy on older models that aren't so fully integrated. I'm sure it can be done based on the wire diagram (maybe anyway). The black/white wire to the coils would seem to be 12v constant power and the other colors signal wires to fire the coil. If thats true then my idea would be to run a 12ga. HOT wire from the Batt. to a 30 amp relay switched on by the ignition with the black/white wire and then to all four coils for a constant 12volts. just like installing hids you can get flickering...the ballast or more likely, two headlights and two ballasts pull alot of amps on start up so it's the same setup but powering the coils. What do you think?

 

I checked the link you shared and I like his idea too, except i'd put a fuse in there for safety sake while testing. I could just get another harness off flea bay and modify it so I can fall back on the original if it doesn't work out. Then of course I have to buy the dang harness and I have the fuse, relay, and wire to do it for free right now...guess i'm my own guinea pig on this one lol.