Newbie... '81 WR project advice?

My apologies if my questions should be easy to answer thru a simple forum search...tried that but new here and not well versed on searching. Could use some expert help with these Q's:

1. Re-installing '81 250WR swingarm after clean-up, new bearings, paint etc. Per the parts manual I have for reference, it looks like I have everything together right, bearings pressed in equal to those taken out and with an O-ring on the outside of each side. There were two very thin fender washers, can't recall exactly where they came out, but re-installed them between the arm and the frame on each side.... When I tighten the swingarm bolt down to a reasonable torque, the arm is bound up, not moving freely. It's not solid tight, but way too much tension on it to be right. Am I missing something? I have center alloy spacer, motor mount brackets each side, "swivel" bushings through bearings each side, O-ring over bushing on bracket side and on frame side, then thin fender washers with slight shoulder toward the bearing on each side, all shoved up between the frame rails.
2. I've source some '83 CR 40MM forks and clamps which I'd like to swap in to replace the 35MM forks that came on the '81 WR. Before I plunk down cash and have them shipped cross country, does anyone know if the '83 40MM forks used the same axle, wheel and brake set up as in '81 on the WR, and if triple clamps go right in to frame as a bolt-and-go? The parts reference found looks to be the same parts numbers for the fork leg, clamps and axle for the '81 CR and XR as with all '83 models, but with the different parts number for the '81 WR parts, it hard to tell.

Much thanks in advance!
Jon in Oregon

I can't speak to number one, in regards to number 2 I've read other people's post here that say you will ruin your handling/cornering on the WR's if you install the longer travel CR/XC forks (240mm verse 300mm) as it increases the fork rake and slows the steering, or something to that effect.

The triple clamps for the 40mm forks use the same bearings as your 81 and the neck heights are identical. I agree you should limit yourself to the 9.5 inch travel WR forks if you plan to ride in the woods. Buy the CR forks only if you decide to ride vintage MX or buy both if you want to do both. Front ends like those swap out easily if you want a truly multi sport mount. Also with the CR forks you should also look for a 1981/1982 CR/XC swingarm to balance the rear against the front. This swingarm is almost 1" longer than the WR and will give you CR rear wheel travel with the same shocks.

Thanks for the tips, much appreciated. I didn't realize there was that much length difference in the two forks, and didn't realize the swingarm was longer on CR/XC.

I did a similar fork swap awhile back on a KTM 495 for later-model longer 40MM forks in place of the 38MM that came stock on the '81 for the more rigid setup. I installed a couple of 1" stopper spacers on the damper rods (heavy pvc conduit) to shorten the top out by an inch or so, to address the same issue. Basically just prevented full extension of forks, and I set springs and sag from there.

Would this be a viable option with the internals of the 40MM CR/XC forks? I've ridden several other bikes over the years with 35MM forks in vintage MX and found there to be a huge difference with the larger and less flexy 40s.

1) I disassembled and verified I've got my swingarm put together right and the distance bushings (name?) that go throught the bearings are .5mm wider than the arms, so should be no binding taking place. Can't find anything in the workshop manual about torque spec for the swingarm bolt, but I assume it's to be tightened down, and not loosened until arm swings free like the old CZ setup?? My guess is that the bind is due to the rear motor mount clamp spacer being a hair short, allowing all distance spacers to push too much to the center and then the frame is jambing on the arms on each side.

2) Determined the '83 40mm triple clamps will work in the '81 WR frame to replace the 35mm, and the front wheel seems to be the same, but the front axle has two different part #s for the 81 35mm vs 83 40mm? Have also heard that the brake arm differs, but the parts manual shows same part # for both...and ideas?