YZ/WR 400, 426, 250F hiccup cure!


blackhawk468

President of Bling
N. Texas SP
Nov 3, 2000
698
0
I am selling my bike and recently have been riding a buddies yz 426. The other day we took it to Performace Factory who did this carb mod. Before there was a hiccup or hesitation on the bottem end of the bike, and this mod compelety cured this. I couldn't believe how much of a difference it made. Anyhow, just thought you yz/wr 4 stroke owners might want to know this. It's a really inexpensive mod, if you want to know contact information e-mail me at blackhawk468@hotmail.com

I hope this is okay to put in here?
 

B

biglou

Of course it's OK! :) I believe the mod that was performed is known as the "BK Mod". (BK being the initals of Tim Ferry's mechanic, who invented the mod, I think) It is a very quick and effective mod.

If you get a 4-stroke, you're gonna have to change your sig line from "BRAAAAAP!" to "BUURRRRRP!" :D
 

wayneo426

Sponsoring Member
Dec 30, 2000
810
1
Sandbar, NY
Yes, the BK works wonders. :D It cured my bottom end hiccups.
Uh-oh, I feel a quote coming on...... :moon:
 

Scott in KC

~SPONSOR~
Aug 28, 2000
212
0
Actually, in respect to the guy that REALLY invented it, BRIAN KINNEY, I'll set the record straight. He deserves a lot of credit. Him and who ever spilled the beans on the gray wire!!

Man, I've been a smart-a$$ lately!!!
 

blackhawk468

President of Bling
N. Texas SP
Nov 3, 2000
698
0
The mod that Brian Kinney is doing is basically an adjustment, the mod that I'm talking about is different and is more effective than the BK mod.
 

wayneo426

Sponsoring Member
Dec 30, 2000
810
1
Sandbar, NY
Blackhawk you cant just leave us hanging like that. Post some pics or pass them on, and I will post them for you. Spit it out bud!!!!
 

vetwfo'er

Member
Dec 18, 2000
124
0
Actually, the P-38 lightning was the first to limit the AP stroke. The BK mod is for the later model FCR's......... Post P-38. The modification limits the AP stroke (less raw fuel into the motor) which will NOT create a rich condition when the throttle opened.

vetwfo'er
 

blackhawk468

President of Bling
N. Texas SP
Nov 3, 2000
698
0
Well Actually, The mod I'm talking about has nothing to do with the P-38 or the AP stroke. I don't know how to do it and I can't provide pictures. All I know is that it works, and he did it on Jeff Gibsons and Lance Hollister's bike. It was done on Tim Ferry's bike as well, and Yamaha took the bike apart and could not figure out what was done to it and they won't tell me damnit.
 

DPW

~SPONSOR~
Jan 23, 2000
344
0
Why can't you post the pictures ? If it's a problem of getting them on the interent e-mail them to me and I'll put them up.
 
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blackhawk468

President of Bling
N. Texas SP
Nov 3, 2000
698
0
I don't know how the guy does the mod or what he does, so I can't provide pictures because I don't know what he did to it. I was just informing everyone that there is another mod out there that can be done its not the BK mod or the P-38 one, and I thought it was more effective.

I'm selling the RM because I'm trying to get money up to get a new bike being the serious motocrosser I am. ;) I'm goin Blue!!!! :)
 

Howser03

~SPONSOR~
Oct 18, 2001
148
0
Go for the 250 2-stroke, more power! AR AR ARH :p Your lucky your down south.... lotsa room to practice. You probably have a big track near ya too. Where I am up North there are no nearby tracks I know of, limited riding areas.....hey does anyone know any motocross tracks located in Virginia or North Carolina?
 
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