wr 400 life
Posted March 10, 2005 - 11:52 AM
Posted March 11, 2005 - 09:20 AM
However, I lost a lot of top end speed. Maybe another bike is better in both worlds, but I wouldn't ride anything but a wr! Bulletproof!!
Posted March 11, 2005 - 10:17 AM
Posted March 11, 2005 - 12:03 PM
Posted March 11, 2005 - 05:18 PM
I lucked out. I feel the '00 is perfect. Steel valves (no titanium valve issues), but it has the 2nd generation FCR carb. Stone reliable, yet plenty of performance for me. They also respond quite well to adjustments.
If it does need rebuilding, you can likely just hone the cylinder, but it depends on the specs and which piston you use. You really have to get it apart to tell. I'd definitely check compression and ask the seller about the last time valves were adjusted and what the clearance was at the time. If they look at you funny and stammer and cough, they probably never even checked the valves. That's a bad sign. I'd also ask how often they changed the oil. Anything less than 250 miles is probably acceptable, but more than that and it was likely rode hard and put away wet. With the right questions, you'll know if the guy was paying attention to the maintenance.
Posted March 12, 2005 - 09:45 AM
Posted March 12, 2005 - 06:10 PM
You may be ok reusing valves if you get one with steel valves (WR400F and early YZ400F), but even then, I think I'd go new. I would not use old springs under any circumstances. When springs break, multiple moving parts attempt to occupy the same space at the same time. This doesn't work out well.
Titanium or stainless valves are between $550 and 800 per set. I don't know about steel. Steel ones will likely only fit the bikes that had them originally, like my '00WR400F. You'll likely have to get OEM if you want steel, and aftermarket mfgs seem to concentrate on Ti and SS. There was no OEM steel valve for any 426 or 450 as far as I recall. So, you will be pushing about $1000 or so.
All this assumes, of course, that the original owner hasn't run the engine without oil. That would likely ruin most bearings and the cams. This means cases get split, and trans bearings become suspect, too. Crank gets split for a new rod kit, then assembled and re-balanced. Oil pump and water pump impeller get a look also. And all parts will need to be hot tanked to make sure small oil passages aren't blocked with varnish and sludge.
This is why it could be anywhere between $1000 and $2500.
BTW, mine is a dry sump engine, I believe the 450 still is. All moving parts aside from the transmission and cam chain rely on oil pressure. This is why the oil needs to be changed religiously on these bikes. It's not because the oil breaks down faster, it's to avoid developing sludge, which clogs small oil galleries.
Posted October 30, 2010 - 06:50 PM
Posted October 30, 2010 - 07:07 PM