Rebuild or sell?
Posted March 22, 2001 - 09:46 AM
I have a 99WR with over 3000 race and dual sport miles on it. Physically, it's in pretty rough shape but runs very good. I also have 2001 YZ426.
I'm looking for advice as to whether it's worth it to rebuild the engine on the WR and restore it from scratch. If yes, what actually NEEDS to be done on the engine. Or are the engine components used to an extent that can't be recovered.
Does anyone have experience with this sort of project? I'm willing to spend about $800 - $1000 if I can get it close to new. I'd also like to make it lighter and more responsive like my YZ.
Posted March 22, 2001 - 12:31 PM
camchain as well maybe, but that's all. it's japanese mate!!
Posted March 22, 2001 - 01:34 PM
I just spent $555.00 to get my 99WR's top end done. Somehow my valves, etc. got all carboned up and stuck open, thereby losing all compression. Only within the last 8 months before the problem did I switch to YZ timing.
My mechanic is a well-known guy in Arizona (Piper Performance) yet he could not say exactly what caused the problem. He suspects some of the carboning was caused by my experimentation with race fuels, octane boosters, ect. The general rule from an engine builder is unless your bike is experiencing detonation, stick with 92 octane pump gas. The ignition system (not the timing) on WRs/YZs is designed to work with 92 octane by the way.
Parts-wise, they put in:
- new valve seals and guides
- new piston rings
- new compression release return spring (prone to breakage)
- honed the cylinder for the new rings
- cleaned up the carb and head
- readjusted the valves
- installed a Scotts stainless oil filter
- changed the oil
- reassembled everything
That's my 2 cents worth. However, nothing feels quite like a new bike...
Posted March 22, 2001 - 04:49 PM
My advice -
buy a YZ seat and tank (Clarke, IMS, Acerbis). Maybe some new shrouds if yours are hammered. While you are installing them, pull the valve cover and switch the cam to YZ specs. While doing that check the valve clearance. Oh yeah change the oil. Find a stock YZ pipe (or buy something else if you need a spark arrestor) to lighten weight and provide more power. Now you have spent ~$500 max, a small amount of time, and you get the lighter and more responsive feel of your YZ (although still a 400 vs 426) with a new seat, tank, and shrouds.
Why mess with a good running thing?
98 WR400F, YZ'd cam, YZ muffler
Posted March 22, 2001 - 06:08 PM
On the flip side, the compression feels mushy and I can tell it lacks power from when it was new. I don't expect it to pull like my YZ due to the flywheel and extra weight, but I suspect the rings, piston and valve seats are worn excessively.
I'm either going to restore the whole thing i.e. top end, new suspension linkage bearings, frame, etc or just sell it.
The front rim is in pretty bad shape as well after from some rock abuse after at least 20 desert races.
Does anyone know where to get used rims?
Posted March 23, 2001 - 04:48 AM
Posted March 23, 2001 - 05:01 AM
Posted March 24, 2001 - 06:40 AM
Posted March 24, 2001 - 06:41 AM