Conversation with YOSH CDI Box Info

Just had a very interesting conversation with Sean at YOSH technical dept about CDI boxes. Take it for what you will because he said it, I didn't:

According to him, the only difference in the YOSH CDI is the rev limiter is set at 11000. The CDI in the E model is set at 9700. The S model kicks in at 10,000 due to being wound out on the street with smoother cams! I was kind of leary since this was diff than anything else I had heard, so I asked him several different ways and he said that was the deal! He said the YOSH cams would cause you to hit the box at half throttle, so that is the only reason for the higher limit. He also said the S and E would interchange with no problem, but the green (kickstand) wire needed to be pulled out of the S harness plug if E CDI is used on S (like BURNED has already told us!).

Just some tidbits I thought you might be interested in! :) Andrew

good info!of course its different everytime you talk to somebody there.last time talked to them the box had a different advance curve also.

they never knew about the green wire deal until they heard it form here.mnelson78 and others talked to them about it and they were told it just wouldnt work.or something with the kick stand system.they do not deal with S much so its understandable.

any body else wanna call for a new story? :)

Funny I talked to them today before reading this the guys name was Craig and he said all the CDI box did was raise your RPM from 10,000 to 11,000.You know in one of my posts I had complained about an elec. shortage on the start of the 1st GNCC and at the last race this weekend it was messing up on the starting line again so I eased off (not by choice it want accept throttle when this mystery happens) and ran it around the parking lot and she finnaly straightened her self out.So I went back to the line and the guys were like "hey didn't that happen to you last week" what could I say I did manage to get fourth in on the start but the problem happened again right into the race and I called it quits.At the car wash she wouldn't run worth a flip I tried everything.Then I got home and put the good ole stock CDI box in place and she ran fine.That's where the call to yoshi came from they said just send her back like it was no big deal after he immediatly thought I was referring to the GSXR CDI box like it was a regular occurance.Hmmm! Still didn't seem to be surprised though.I asked if I could run the stock CDI and said yeah there is no difference besides the rev limiter.I wan't too sure about making a post about that issue until I have the final verdict but I am 99% sure the yosh box is the culprit and I could flat kick Fujio Yoshimura's ass for ruining my races and costing me so much money I let everyone know how it turns out.

Make sure and let YOSH know how you feel and the money they cost you. They may kick in some type of hardware perk to make amends...then you can sell it to us! Anyway, givem ell just because they should be the step above...Andrew

I wish I had a way to scan because I have the installation instructions. The ONLY difference between a E box is the rpm. 10.5 to 11,000. It states clearly that the curves are the same. Maybe more of an improvement for us S guys but does little for an E.

Quote from the Technical Parts service manual...

"This racing ignitor has been changed. the rev limit from 10500 to 11000.No ignition time has been changed."

Remember its the same as an E, not an S.


that settles it!must be than.thanks crisis!

it definately has different curve than the S feel the difference in the mid range. :)

and the rest of it is in japanese :)

and the rest of it is in japanese

thats the coolest part!they could be making fun of round eye and you not know it! :)

I am going to have to hold my thought on thinking the yosh CDI is to blame.I havn't had it out of the garage and it is a sparatic occurance so dont't hold me to it.I will know in a day or two if I should put my foot in my mouth.

did you clean the powder coat off your frame where the grounds are?at the coil mount?

Yeah twice maybe three times with a dremel.Any other suggestions would greatly be appreciated private or not.

My bad it is not the yoshi cdi box. Good thing I didn't claim it 100%. Just have no spark.

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