What years have leak jets?

7 replies to this topic
  • pablo83

Posted August 20, 2009 - 10:53 AM


My '01 WR426 does not have a leak jet. Neither does my '00 WR400. What years have them? Will a quickshot adjust AP squirt without the leak jet?

  • William1

Posted August 20, 2009 - 12:14 PM


A leak jet reduces the volume and sensitivity of the AP. On your carb, the taffy mod does the same thing for $.79 instead of $149.00 for the overpriced QS. Your money.

  • pablo83

Posted August 20, 2009 - 12:39 PM


The taffy mod limits max AP squirt duration. I want max duration, I just want less fuel in the squirt stream.

  • William1

Posted August 20, 2009 - 01:32 PM


You are going to have a hard time, if I am reading you right.

You need to have enough fuel at pressure to last the duration of your desired squirt. If you use a leak jet to bleed off volume (and pressure) you may have a squirt that does not last the duration.

Why do you think you need a 4 sec. squirt? That is a crapoad of fuel and you should of been at redling after about .5 to .9 seconds anyways.

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  • pablo83

Posted August 20, 2009 - 03:27 PM


I don't race. I use the bike to cruise around mountain trails. I don't always keep the engine revved up so I'm not hitting redline in .5 to .9 seconds. I need the AP to work right when I come around a corner and suddenly there's an obstacle that requires speed to get over, but it's running rich when the AP is triggered.

  • GCannon

Posted August 20, 2009 - 04:55 PM


To do what you are trying to do the way you want to do it, You need the AP cover with the adjustable leak jet, Powershot I think is the name.

You should be trying to tune squirt timing and squirt duration separately.
squirt volume is also important and when you get your AP correct you will have lean jetting so that will also be a consideration.

The BK mod worked very well for me on the 02 426. To each his own if you want to do something differnt.

The stock 426 has such a high volume squirt that it covers up the main jet when the vacuum signal builds which happens as rpm's build.

You only need the squirt early in the throttle opening to cover up that big vacuum leak (lean condition) you just created when you opened the throttle. once the vacuum signal builds your proper jetting will have a better chance of controlling the mixture more precisely than that fat squirt that is hard to tune.

Short duration squirt timmed very early without hitting any part of the carb (slide) would be a good start, Half to 3/4 of a second is all you need then fatten the jetting to make up for the tail end of the squirt that is not there any more.

good luck:thumbsup:

  • GCannon

Posted August 20, 2009 - 04:57 PM


BTW 2003 WR 450 was the first WR with a leak Jet

  • pablo83

Posted August 20, 2009 - 07:17 PM


BTW 2003 WR 450 was the first WR with a leak Jet

Thanks :thumbsup:


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