Used 1999 WR 400
Posted October 21, 2003 - 06:00 PM
Posted October 21, 2003 - 07:16 PM
I later installed the 426 Rod & Cylinder, and did an .80 Over BIG BORE, I use the YZ Timing ,and it runs great, it measures out to be about 444cc.
Posted October 22, 2003 - 06:21 AM
Posted October 22, 2003 - 07:38 AM
Posted October 22, 2003 - 10:28 AM
If your son is racing, or is an aggressive rider he will burn up the stock clutch.
Why would you have to replace the stock clutch unless someone has abused it? If you dont ride the bike like a two stroke then the clutch will be fine. The only time I have had to ride the clucth a little was on a extremely steep hill climb to keep the front end down.
Mines a 99 and still has stock plates.
Posted October 22, 2003 - 10:53 AM
I think that pretty much covers it. Rejetting the carb will be necessary, but it is not a free mod.
Posted October 22, 2003 - 11:20 AM
There is my own mod, and there is the Taffy Mod for the 98/99 accelerator pumps. Both work, although the Taffy mod is not intrusive to the carb body as my mod (KL mod) is.
This sets the duration of the AP squirt. Stock, the squirt can last up to 4 seconds, which is waaaaaaay too long. Generally, 0.25 > 0.5 seconds is optimal.
There is also the blue wire mod which cuts voltage or something if the bike is in neutral. Reports have indicated cutting the blue wire eases starting.
Posted October 22, 2003 - 01:04 PM
Reports have indicated cutting the blue wire eases starting
I did this mod about 6 months ago and I can attest that it does work. I used to foul plugs all the time when the bike was warming up. But it hasnt since.
And instaed of cutting the wire, Kevin means "unplug it"
Posted October 22, 2003 - 01:46 PM
And instead of cutting the wire, Kevin means "unplug it"
You can cut the wire right at the neutral switch near your countershaft sprocket. If you trace the wire to the harness under the tank, you WILL find all the leads off that harness are all DEAD leads. I removed the netral switch gizmo at the engine, used a Ty Davis billet plug to plug up the hole, and disconnected the wire harness under that tank.
I did this while re-wrapping all leads after installing the coil on plug setup (~$50) from Mike Dean out of Wisconsin.
Posted October 22, 2003 - 02:04 PM
Posted October 23, 2003 - 06:48 AM
I have never fouled a plug, and it seems to start pretty easy. But it doesn't sound like it will hurt to try the blue wire mod. I let everyone know if I can honestly notice a difference.
Posted October 25, 2003 - 08:58 PM