Some simple Q's about WR vs. YZ

4 replies to this topic
  • Henrik

Posted March 31, 2003 - 10:52 AM


Ok, I'm new to the game so bare with me. I've looked through the forum and I've seen some things I'd like to have answers to. So, I'll start off with the questions:

1. "The grey wire" retards the timing - cutting it will make me happy. True or false?

2. Can I run YZ-cam timing and still use the WR pipe?

3. Big difference between the WR and YZ pipe?

4. How do I know if it's jetted correctly? On a 2 stroke you check the plug but four-stroke???

5. This is a tricky question and I don't think it's even a good question: How much taller are the gears? I'm curious because I can't decide wether to buy a YZ or WR... I'm worried that it will be a pig if I run dirt tracks......

  • BrandonW

Posted March 31, 2003 - 11:45 AM


1. The Grey Wire is the difference between YZ (disconnected) ignition mapping and WR (still hooked up) ignition mapping that is EPA compliant. Disconnecting the wire will make your bike run better, and most people who do this are glad they did. (Don't cut the wire, just disconnect the connector and pull the grey wire out of the back and reconnect the connector)

2. YZ timing will make the bike generate power earlier in the rev range. You will loose a little top end, but I have done this, and I will not go back to the WR timing.

3. WR pipe is steel and heavier, but it also is spark arrestor compliant, which is required for all forest service lands.

4. To ensure that it is jetting correctly, you got a lot of work to do. Spark plug testing is one way, trial and error by riding is another. Guru's here will answer questions as long as you are willing to ask them.

5. Not positive, but I think that gears are only different in 1st, 3rd and 5th gear. (Are you talking NEW, because the new YZ's have a 4 speed gear box, the WR retains the 5 speed gearbox, but both are very capable) Many people have converted the WR for dirt-track racing only, and they do fine.

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  • wr250rr

Posted March 31, 2003 - 03:17 PM


1st gear on the WR is alot shorter than the YZ, 4th gears are the exact same, WR has a 5th gear. I like to call it the passing gear. :) :D :D

  • Henrik

Posted March 31, 2003 - 08:45 PM


What are your opinions on WR's with YZ cam timing? Will I notice any loss in lowend torque?

  • wr250rr

Posted April 01, 2003 - 01:29 AM


I never noticed any loss of low end torque on my wr250.
Because the powerband signs on so much sooner, it feels like it has more low end.
One thing you will notice is that you will lose alot of the down compresion when you chop the throttle.


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