Any Techies out there have the real scoop on Blue Wire

16 replies to this topic
  • SoCalWR426

Posted April 05, 2002 - 10:34 PM


Ok, The blue wire has been getting alot of mention lately. I have been following these threads very closely, but it still seems that this latest mod is still shrouded in mystery. I have yet to see a Yamaha techie like Mr. B.K come forward and tell us exactly... A. what this wire does,(actualy this is answered as nuetral rev limiter) but why a nuetral rev limiter?.. B. What are the pro's and con's of disconecting blue wire. There has been alot of seat of the pants testing and reports, but I would like to see a real explanation.
Thanks for your support..


[ April 05, 2002: Message edited by: SoCalWR426 ]

  • lewichris

Posted April 05, 2002 - 12:48 PM


i wont do it. They say it changes the your rev limiter while in neutral. Scarry.

  • Quickrik

Posted April 05, 2002 - 02:29 PM


Its all to do with emissions and noise testing.
theory is you can just hold it FWO and get a good reading

  • motoman393

Posted April 05, 2002 - 04:23 PM


About 12 rides on the bike so far with the blue wire disconnected and it works awesome. It nows starts within 3 kicks hot/cold/after stalling. It also seems to shift noticably better when speed shifting from 1st to 2nd gear! You also can tell it revs higher in neutral too (better for starts) Im impressed and I highly doubt it will ruin my bike...if I thought it would, do you think I would have disconnected it? LOL Later,


  • robswr426

Posted April 05, 2002 - 06:34 PM


ok where is the blue wire now

  • Mark_Cantrell

Posted April 06, 2002 - 03:27 PM


The rev limiter on WR250F is 7500 in neutral and 13,500 in gear. Having a low rev limiter is scary?

  • SoCalWR426

Posted April 08, 2002 - 07:58 PM


Still no real answer!.. Does that mean that no TT'ers have the real answer? I'm not talking about theory or seat of the pants testing, although that is all good to have, and testing is allway's needed. But the facts. Just as we know the facts and true functions of the grey wire, BK mod ect.ect..


  • z4me

Posted April 09, 2002 - 01:59 AM


Originally posted by SoCalWR426:
Still no real answer!.. Does that mean that no TT'ers have the real answer? I'm not talking about theory or seat of the pants testing, although that is all good to have, and testing is allway's needed. But the facts. Just as we know the facts and true functions of the grey wire, BK mod ect.ect..


We had official word on what the grey wire does? I don't think so - purely speculation and end user data is what has made us switch.

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  • lewichris

Posted April 09, 2002 - 04:23 AM


yea and i felt not boost after trying the gray wire disconnected. I think the guys who wanted to feel a boost felt a boost. All in your heads man.

  • SFO

Posted April 09, 2002 - 05:10 AM


Before the blue wire there was the grey wire.
I disconnected it and ran back to back tests with a vortex ignition on the dyno.
There was no difference except for a higher redline on the vortex.
No difference in hp except the torque setting gutted the torque curve.
Now we got a new wire to cut that will make it better?
I don't want a higher rpm limit, my squish is set kinda tight for that.

  • yamaha.dude

Posted April 09, 2002 - 11:43 AM


Did any off you guys feel a difference when you removed your airbox lid? Your baffle? or cut your throttle stop?

None of these are "official" factory fixes, but that is the whole point of TT - to share the user experience, not to run the corporate scripts... We all know why there are restrictions and other controls on our bikes, and we all know that when we remove them our bikes work better - not because we read a factory service bulletin, or because our dealer took us to one side and gave us a "factory racing" setup tip; but because it works for the big sample... i.e. A lot of TT members, who ride probably millions of miles/hours per year combined...

I think that the 'folklore' of the blue wire is getting a little distorted... it helps in starting your bike, not a performance mod as such to give you more revs, or more horsepower...

I haven't done it, but then I have no problem with starting my bike... Other people have reported success, perhaps it is psychosomatic, perhaps it is real - whatever - if it makes people feel better about their bikes, then that is a positive thing...

Even if there was a factory technician on this board, he /she would probably be constrained from giving us advice such as "cut this wire"...


  • Chaindrive

Posted April 09, 2002 - 11:52 AM


I think we ARE being secretly monitored by Yamaha...

450cc,e-start,20lbs lighter,flatter tank/seat, street legal, lower cost...(get all that?)... :)

  • lewichris

Posted April 09, 2002 - 12:13 PM


[QUOTE]Originally posted by yamaha.dude:
[QB]Did any off you guys feel a difference when you removed your airbox lid? Your baffle? or cut your throttle stop?

Anyone who says no to the above things should probably stick to something that dosent have a motor cause they probably removed the wrong things. I am sure that you are inplying that you DID have an effect. Things that are electrical are diffrent. i work with electronics. i know that by lifting just one pin on a 120 pin micro can effect a welth of things but still can make the circuit appear to run fine. Is anyone here A Yamaha Engineer incharge of the Digital CDI Box and all the wires that come out of it. If so i would love to ask you a million questions. The restrictions that are put on the bike through the electronics in that little black box is given to that micro after thousands of tests and verification have been done wih it.In hot air in cold air in shock in water in humidity. We have a test chanber here that controls all of these things. i know the tests done in an enviormental chamber. I can understand the theory's behind both wires. But how do we know it isnt the brown wire or the green wire with a white stripe on it. We all want more power and better starting bikes and more hit in the mid range. So my question is Who is the person who told whoever that it is the light blue wire that does this. If it was a yamaha engineer how did you get him to give out insider trading info. I just want to talk to the guy and ask about a thousand questions. My point is there is no scientific data done by a lab to support those theorys of cutting wires. If i am talking outta my ass here someone just tell me. I just want to know.

  • yamaha.dude

Posted April 09, 2002 - 04:19 PM


Hey ChainDrive - you left out the cupholders... :)

Lewischris - I hear what you are saying, and if I recall the original post on the blue wire, it was a dealer mechanic that told the poster and he shared it here and now look... damn near everyone knows now... LOL

I think the point is that we are never going to get the "inside info" from the factory - it will never be public domain - so we have to experiment, reverse engineer, whatever to find out these tricks - I doubt the Vortex guys just downloaded a PDF from and went on from there... They started with a basic modular unit and experimented... using scientific principles of recording data sets, re-running the tests with variables, looking for the limits etc...

Imagine the bike we would have today if people had never tried to change them, we would all be on steam powered penny farthings... LOL

I agree with you, that they have it close to optimum, but they will always back off and err on the side of safety, longevity, emmissions, production costs etc... that is why the factory racing teams have bikes that are so (subtley) different... R & D

I am sure we all have questions, but you can't even get a general number for the US or Australian Distributors from the website... maybe we need to get a posse together and go to Japan, take over the production line for a month and turn out some special TT models... with all the mods (and more) already made... Hands up who can re-program the robots... :D


  • SoCalWR426

Posted April 09, 2002 - 08:14 PM


Yamahadude and lewichris are on to my line of questioning. I was hopeing another factory type mechanic such as Brian K. would step forward as he did with what would become the famous BK mod. There would be endless low throttle bog stories and complaints here if it was not for him stepping up with insider info.


  • lewichris

Posted April 10, 2002 - 06:16 AM


well i have the 1998 WR and i here there isnt a way for me to do the BK mod to my bike. i wish there were but i can't.

  • Ron_in_SoCal

Posted April 10, 2002 - 08:33 AM


Oh, but there is a way:



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