F6 cdi question

[Outboardjulien]

Hello everyone. I am new here.
I have a desire to turn a 2008 F4 portable into a 6hp portable. From what I see the only difference is the carb jets and cdi.
a F6 cdi 68R-85540 cost about $250-300, so that does not make practical sense.
My question is; is there a cheap cdi that will advance curve correctly and rev limit at 5500rpm? Also I can buy a F8 68T-85540 cdi cheap. Would it work as well?
Thanks everyone

[boscoe99]

Welcome.

Are you asking if an F6 CDI can be used in lieu of an F4 CDI?

If so, what is the part number of the F4 CDI that is to be replaced?

[Outboardjulien]

I was looking at the wrong model. The cdi I am after (I think) is a 6BX-85571-00-00
I want to turn a portable 4hp F4 into a 6hp F6. So I need to change out the cdi to one that will rev to 5500 rpm. I found one on aliexpress for cheap but I'm skeptical of it being a compatible part. I guess I could order it and see what it does.you can see the cdi coil on Ali express website by searching for 6BX-85571-00-00 (that is the F6 portable Yamaha part number)

[rodbolt17]

sell the F4 and buy an F6.
would be way cheaper and easier in the long run.

[Outboardjulien]

I found a cdi dirt cheap on the net. Plus boats and motors are no fun unless you modify them and make them unreliable. Thinking I might want to port and polish the intake and exhaust. I'm looking for max power from a portable without going 2 stroke.

[boscoe99]

We need rodnut to tell us if that is really a CDI or not. Does not look like one.

Yamaha call it a T.C.I. Unit Assembly. In some of their models, TCI stands for Transistor Con*****ed Ignition. Not a CDI at all.

Looks to be just a stator/coil combination device. If all it does is generate electricity to spark the plug I am not understanding how it will create more power. Any power, let alone 50% more (4 to 6).

Major differences between an F4 and an F6 are going to be carburetor and air intake system related I would hazard to guess.

[boscoe99]

Here is what is being discussed for those that might be interested. Reminds me of a part from a lawn mower many years ago.

[ausnoelm]

I found a cdi dirt cheap on the net. Plus boats and motors are no fun unless you modify them and make them unreliable. Thinking I might want to port and polish the intake and exhaust. I'm looking for max power from a portable without going 2 stroke.

Not too sure about a 50% increase by simply changing the ignition system, also not sure about the max power without going to a 2 stroke either, just buy an 8HP and double your HP in one go.

[Outboardjulien]

Thank you all for expressing interest in my post. It's not about just going out and buying more power. I can do that. It's about playing with outboards and seeing what can or can't be done. I agree the part does not look like a cdi unit. From my query on the net I do delive that rpm limiter of some sort and carb jet size is the only difference between a F4,F5 and F6 portables. When I get time I will print off the parts list for F4 and F6 and cross reference them to find the difference.

[pstephens46]

Here is what is being discussed for those that might be interested. Reminds me of a part from a lawn mower many years ago.

Just replaced one of those on my echo blower. Ask Scott. He will vouch for me!

[Outboardjulien]

Strange... when I look up the part for 2006 and newer they call it a ignition coil with cdi.
When I look up the part on ali express the picture looks like the one in the previous post. The part number is 6BX-85571-00-00. Also the part numbers differ from F4-F6. The one on ali express is $15 USD with free international shipping. Yamaha OEM is $251.88

[Outboardjulien]

FYI I'm using boats.net for parts diagram

[rodbolt17]

cause some of the tiny mites used a TCI ign and some used a CDI ign.
why?? I dunno but the two systems are totally different.

[almetelo]

The only diference between the F4B and F6C are the carburetor (large jets and ventury on F6) and the TCI because seems to allow to get higher revs

F4B 4500 rpms
F5A 5000 rpms
F6C 5500 rpms

I have a F6a: is light but that single cylinder makes it noisy