'78 WR (OR?) Restoration

Should have started a build thread a while ago instead of my random posts, so here it is. I had been working on a cosmetic resto of a '77CR250 when a fellow vintage racer said he had a '78WR250 he was getting rid of cheap, so I could not resist.

Motor was locked, but it was a fairly complete bike. But just about every area needed attention.

Plan was to build a New England vintage racer with a bit of improvement in suspension. Did the standard bag & tag process and inspect what you have. I have a two bin system. One bin for all dirty and to-be-restored/replaced parts, and then a bin for the parts that are done. But nothing, and I mean nothing gets thrown out until the build is done - I learned that lesson the hard way.

Swingarm axle fought me more than usual, it took me several days of soaking in penetrating oil and cycles of heat, as well as a 2lb hammer to get it out. During this process I noticed a hairline crack in the rear engine case where the motor mount passes through. I did not know it then, but should have been a clue as to a deeper problem with swingarm.

I always go back and forth on powdercoat vs. paint on the frame. Can touch up paint easily, but the PC is so darn nice. PC it is with this frame. Did not seem that bad on first examination - no areas of rust-through, rear loop was bent down and twisted, and kstand bracket was torn. Husky dropped the ball on the kstand bracket, way too thin metal for that bracket. Using clamps and properly placed wood blocks the hoop bend was fixed. Not the greatest pic but you get the idea.

Thanks to this site, I got a good education on fork swaps. Pros and cons each way, but decided I wanted to make the 40MM forks work on this bike. Challenges are (1) finding the forks and (2) keeping the length close to the 35MM forks so as not to f up the steering characteristics. By pure luck I happened upon a complete 40MM fork set with triple clamps. I love the embossed "Husqvarna" on those forks. However after mock fitting I found that they were the longer CR forks. Because of the travel, you can only push them so far up in the clamps before the bottom tubes hit the bottom triple clamp. Solution was to find WR dampers with would have only about a 10 inch stroke. Drew at WER came through. Here are the forks torn down before paint, which will be gold. You can see the difference in length of the WR and CR dampers. Of course new seals and top out washers will be used. Bronze bushings looked ok.

Ol mate does a neat trick with the cr forks to reduce them back to WR travel, he replaces the top out washers (which pooh themselves too regularly) with a small top out spring which reduces the cr damper back to approx wr length and runs the wr sliders.

Here is try #1 on replacement kstand bracket - extra thick. But this will have to be redone as swingarm bore is no good. I cant weld for poo, but luckily another vintage nut in my area was a welder in a former life and is very good at welding chromoly and aluminum. To have this weld done, as well as repairing a muffler bracket on the frame, I traded him Ceriani forks and triple clamps from a vintage KTM that were of no use to me.

Those of you who read this when it was first posted may wonder what happened to the custom machines steering stem cups. Those were actually for the '77CR250 build I have going at the same time. Brain fart.

Frame and silver bit powder coating is on hold until swingarm #3 arrives and the kstand bracket is re-welded up, but lots of other stuff to do. Engine was torn down to inspect. This engine was locked when I got it, and was unsure if it was a seized piston stuck crank, or all of the above. Cylinder of course would not pop off, but with my usual treatment - several days of soaking, cycles of heat and gentle blows with a dead-blow hammer and cylinder lifted off. I don't think it seized, but cylinder corroded a bit probably sitting for so long. The real issue was the crank. I could tell by the dirt in the crank that this bike probably had been swamped and left to die somewhere in the corner of a barn or shed. I had a bitch of a time splitting the cases, to the point where I feared I would strip the ignition case holes that my three-armed tusk puller screw into. I saw an old post on here where a steel plate with a 3 inch hole and a three jaw puller was used, so I tried that method. This home brew tool allows you to use all four ignition screw holes and seemed to put a higher and more even force on the cases. Voila...they split. I could then see why they were so stubborn, the main bearing race was rusted to the crank, most likely due to the swamping of the bike and being left to die. The autopsy also revealed a mess of rotting magnesium:

So the cases now had two strikes - cracked mount and rotted crank cavity. My welder friend said he could fix them, but in that they were not the last cases on earth, I looked for replacements. Had a very nice offer from someone on this site to buy 3 partial engines for $200, so I grabbed those in hope of getting cases that would work as well as a useable crank. There was a 2066 motor in the lot, but the right side case also needed welding. There was a 81 CR250 bottom end but I did not think that would swap over as it was the larger splined counter shaft. In hindsight probably could have used the entire CR bottom end, but I got a little spooked by the used cranks, which probably were fine, but who knows. I posted on Mark's swapmeet and someone in Cali had a nice set of 2066 cases that they sold me for $50 plus shipping. Degreased them and heated in a little dutch oven I use to heat cases and hubs, and bearings came out with no issues. I will degrease a few more times then lightly sand and paint with PJ1 Satin black. Its rattle can, but I have had excellent results with this stuff and the sheen is a near OEM match.

Triple clamps and hubs were powder coated satin black. I boxed the hubs up so quickly to ship to Buchanans that I did not take photos, but here are the 40MM triples:

While waiting on an OE replacement rod kit to rebuild the crank ($320 !!) I focused on rear shocks. The bike came with period correct Works shocks, 16 inch eye to eye. I pretty sure the correct original shocks with 15 inch Girlings, but I always liked the early Ohlins. Talked to Drew at WER and by chance he had an old set of Ohlins he picked up at a swap meet, and he rebuilt them to new condition. Even better, he took the three partial engines I had bought but could not fully use in trade. Since I am a taller rider, and have a little extra fork length to play with in the 40MM versions, we decided to make the Ohlins 16 inch eye to eye. Still need to box those engines up and send to Drew, but he sent the shocks up any way:

Fasteners, brackets and plated bits were up next. I have a local plating company that will take a box of old bolts and brackets and for $100 they re-plate with white or yellow zinc. This is the first time I will try to replate nylock nuts, not sure if the nylon will hold up, but I have the correct nylock repro nuts if not. He charges me a fixed price so no harm in putting extra stuff in that might not work. The plater puts them through a prep process but I have found that the better shape you get the stuff in, the better the results are, so I degrease and then wire wheel each part. The before is below. Ill have the stuff back in a week or so for the bling after shot. The other issue you need to deal with is hydrogen embrittlement, the plating process can make hardened steels weak by entrapping hydrogen. The solution is to bake critical parts around 350 degrees right after the plating. Really only necessary to do this to the axles.

Great posts...keep them coming...
And when it's done...consider giving it a go in the AHRMA MA XC series!

This is a cool thread.

Good stuff, I'm following it with interest. I have another resto to do.
Keep it coming!

I used a satin black etch primer to do my cases, have had excellent results. I had my axles replated but not baked at 350 degrees..should I be worried? its had some high speed braking efforts..would that be hot enough? note, I had to sand my axles down after plating, wouldn't fit through the bearings...not something I had figured on.

I used a satin black etch primer to do my cases, have had excellent results. I had my axles replated but not baked at 350 degrees..should I be worried? its had some high speed braking efforts..would that be hot enough? note, I had to sand my axles down after plating, wouldn't fit through the bearings...not something I had figured on.

Suprize, the baking needs to occur soon after the plating, but I would not be too worried, its one of those things that are designed for military super critical stuff. Not saying it cant happen, but Id ride it. Yes replated axles are tight through the bearings, I hit it with a wire wheel if I have clearance issues.

Etch primer with no final coat? I use a marine phosphate etch primer designed for outboard motors followed by the PJ1 rattle can.

Looking good Dave!

Need some pipe info. When I pulled the silencer (#2) off the pipe, the silencer end of the pipe showed a perforated pipe around which packing had been stuffed - but I don't think that is where the packing goes, it should be in the silencer portion (shown as #73?). But maybe the parts fiche is not correct?

#73 is just a spark arrestor. No packing in there. The packing (or wadding) fits over the perforated pipe inside #2. I think I posted a "how to" in one of your other posts.