FJ_Kevin's CR250, 390 & 430 Vintage Husqvarna Restoration Extravaganza!

Alright boys, welcome to my new Vintage Husqvarna Restoration Extravaganza thread!

I've really done it this time :eek1. I have a shop full of beat up old Huskys needing lots of work. The plan is to get them all going, have some fun and maybe even race a few of them .

Now some of you may already be familiar with my "Building a YZ465 Factory Replica " effort. This thread will continue in a similar vein but will instead feature air cooled Husqvarna's of the late 70's and early 80's. The current lineup includes a 1980 CR250, 1978 CR390, 1980 CR390 a 1981 CR430.

I was initially going to chronicle these new efforts in the Yamaha thread but was persuaded by WFOPete that the topic was different enough to warrant a fresh start, so here we are.

One thing for sure though, I will still be tinkering with the big bore YZ/IT's ... they are not going away! And I am eager to see how the Yamaha's and Husky's compare.

I also plan to continue to report on events and races that I attend. At first I wasn't sure as to which thread I would report these to. But I have since decided that this will be determined by which bike I ride. So if I race a Yamaha the event report will go in the Yamaha thread. If I race a Husqvarna the report will go here.

One other thing. I am not a Husky expert by any means. Please keep this in mind as I muddle through all this. And please feel free to chime in with any comments or suggestions. All are welcome!

So let's have a quick look them all before we get started...

First up is this 1980 CR250. It has a stuck motor, blown Ohlins shocks and who knows what else. Here is the 1st snap after arriving home.



Another as it leans against the shop door.



Next is this 1978 CR390 bought off ebay. It has a stuck motor also .



This next one was not a complete bike but rather an assemblage of spare parts collected over time. I had some crazy ideas for this but eventually I realized I had about enough to build something close to a 1980 CR390.



Here is in a pre-build mock up state


And finally is the 1981 CR430. This was a pretty big mess. At the moment it looks like this with a freshly powder coated frame. The motor runs but is on the bench for inspection.



Much, much more to come!

Saw Heikki race a few times.
He was incredible on any Husky he ever rode.

I owned a 1976 CR250 back in the day. Wonderful memories.

Go Kevin!

Love the old Huskys. I remember back in 1978 I was a kid, had no money and was riding an old Yamaha tt500 at a local hare scramble in SE TN. In pulled this big enclosed van and out came a couple of Husky sponsored riders. They absolutely smoked the field on those Huskys.

Looking forward to the builds.

You have got it bad! I could only dream of owning a Husky when I was young, I always loved that classy chrome on the tank.

Even though I have moving back and forth between all these bikes most of the recent effort has been on the '78 CR390 and so that is what we will cover first.

Now some of this I have already written about in the Yamaha thread. To bring the newcomers up to date and to have the full story in the same thread I am reposting some of this material here along with a few additional comments. Also included is some of the original comments as I think these too may be of interest to those working Husky projects.

So from the other thread...

Why a Husqvarna?

While I still vastly favor my Yamaha's and always will, I was interested in building a twin shock mxer, specifically a '79/80 twin shock Suzuki RM 250/400 like this one found on the web,



And I think I have mentioned before how I really loved my old RM250...



... but I looked and looked and could just never find one in my area.

Instead, these Husqvarna's kept turning up.

I ignored them at first. Euro crap, I said. I remember riding a friends 390 back in the day and was not impressed. Plus I had Maico's - always a chore keeping those going! But finally I caved and bought one, then another and then another!

I think it was those sexy alloy fuel tanks that got me. Reminds me of my Moto Guzzi Ambassador.

Anyway, for now we are just going to talk about this 390. It is a 1978 that I bought the next town over for $700 after 1st finding it on ebay.

While the price may or may not sound too bad, I was taking a real chance as the motor was locked up. And I knew nothing about the potential evils lurking in the hearts of old Huskys.




More to come...

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I agree, always liked the color schemes, especially the red with the green number plates. And I really favor the CR models with those alloy tanks.

"On Any Sunday" and Malcolm Smith was a big influence too!

All right! Another FJ_Kevin build-info-entertainment thread!

I'm no Husky expert by any means but I seem to remember the black tank was the OR model... CR engine tuning with WR gear ratios, intended for desert. 17" rear rim. Or something like that.
I'm sure I'll be corrected by the experts.

Hi Eric,

Apparently the CR390's, WR 390's and OR390's all came in black at one time or another.

Here are some of the brochures I found on the web while researching these project bikes.

First is the 1978 CR390 like mine, notice the small alloy tank.



This next one shows the WR390 in the upper right (250 is on left). The tank is larger and in steel. The gas cap is centered on the steel tanks and offset to the right on the alloy CR tanks. The WR's have the lighting kits also. I believe this is a 1979 or 1980 brochure as these show the updated frame (with extra tube running in front of the updated air box).



Next is an OR390 with the earlier frame like my 78 CR



And now here is the OR 390 with updated frame like the WR posted above. Looks like this version came with Ohlins shocks too. I think the OR's have the larger capacity steel tank as well. No lights though.



I believe this next one to be a 1979 CR250 (the 390 would have a black tank). It has the updated frame and air box, the alloy tank but still retains the rear fender loop. Also notice the left lower corner of the seat forms a near 90 deg angle.



The 1980 CR has the update frame and air box, the alloy tank but drops the fender hoop. The seat tubes have a kick up at the back as does the seat.



It is a bit tricky to get the correct seat cover for 1978,79 and 80 model years. Took me awhile to figure out why my new seat cover didn't fit my seat! More about that in a future post!

So let's have a closer look at the beast for some 1st impressions,



Again, this is a CR model, Husqvarna's designation for the motocross model.

They also came in WR (wide ratio or woods racer?) and OR (off road) versions as shown in the previously posted brochures.

My understanding is the CR model came with increased suspension travel and a close ratio gearbox. I believe the pipe is a bit different too. The WR seems to have a larger silencer and may be double walled in some sections to soften their bark.

I am finding out that the '78 CR390 is quite similar to the '77 version. I believe the frame is essentially the same. However, the '78 came with the vastly improved Timpken tapered steering bearings while the '77 still sported loose balls (always a dangerous practice ).

All the Husky's of this era were pretty attractive in my mind. Black with yellow plates was the color scheme for the big bore CR390 while the 250's used Red with green plates as shown in the following photo.




It turns out that the choice of number plate color was not really Husky's. In fact, they were simply following the requirement of FIM Grand Prix motocross that all open bikes run yellow plates with green reserved for the 250 class.






CR390 Suspension

This particular bike came with non-original S&W shocks which I think are early versions of the Progressive brand shocks sold today.

I am not quite sure what shocks it came with originally as some articles seem to indicate Girllings while others mention Ohlins for '78.

Currnut shocks were another shock supplied on Huskys but I don't thing they were used on the CR motocross bike. I know we have a Currnut expert in the 2-stoke forum, perhaps he can chime in here with some more definitive information .



I did begin to formulate some opinions upon closer inspection of the bike. I have to say I thought the top shock mounts looked rather light duty. Shock bolts looked undersized too.

Same with the swing arm mounting plates. They looked pretty thin to me. No extra gusseting around the bolt like you sometimes see on motocrossers from other manufactures.

I have read about ovalizing of the swing arm bolt hole if not keep tight and I can now understand why. Fortunately, this one hasn't suffered this problem.

Compared to the Yamaha's, I thought the swing arm and rear axle diameters were undersized too... same for the wheel bearings, hmmm.

The front end was also a bit disappointing as the front fork tubes are only 35mm. According to Dirt Bike front travel was 9.5 inches. I remember the tube diameter as being a major knock on Huskys of this era and I must say they look pretty whispy compared to the 43mm forks on the Yamaha's. I was thinking a fork swap could be in this bikes future. However, now I think I will just keep this one stock where possible. I'll try my experiments on that piece meal '80 390 :eek1.

More to come...

Alright, so I already mentioned that the motor was locked up on this bike. I suppose I was hoping that it was just the top end that was frozen and the crank was OK.

It turned out to be just the reverse. With some liberal application of WD40, the top end cam loose and off will little problem.

Unfortunately, the crank case was full of dried up sludge. It looked like old fuel must have leaked into the bottom end where it all turned bad over a decade or so.

The crank was totally wiped so a full rebuild would be in order.

It is a little bit interesting to compare this Husky motor to the YZ465/490 motors I have been working with.

The Husky layout is a mirror image meaning every thing is on the opposite side. Yamaha has kicker and clutch on right, ignition and counter shaft sprocket on left. The Husky has kicker/clutch on left and ignition and drive on right.

There are other differences too. One key difference to be aware of is that the flywheel nut is left hand thread!

In my search for a crank, I ran across more than one where the flywheel side threaded end was sheared off, likely the result of assuming right hand thread together with use of an air wrench !

Other than the flywheel nut, the cases split fairly easily. I used this case splitter purchase off ebay ($50 shipped) shown in the following photos. It seems to be drilled to work on a few different models and worked just fine. I guess I should have made one but I didn't happen to have a large enough piece of steel around. Ah well, I guess I have enough to do.





And of course non the flywheel pullers already on hand worked on the Motoplat flywheel so that was another ebay purchase (~$15 I think).

Unlike the crank nut, the flywheel & puller utilize right hand threads. I'll see if I can find the thread size so others will know which puller to purchase as there seems to be a few different ones available for these old Huskys.




So I am a little short on photos at this point but here is one with the cases opened.





And it gets worse !

OK, so almost up to date with some of the previously posted material. Next are the comments brought over from the other thread. Sorry if this is repetitive for some but over the long run it should be more helpful to have all this in the same thread.

From WFOPete:

Kevin, Gotta agree there is something "right" looking about a twin shocker. A few years ago I bought a 81 KTM GS250 for Cross Country/MX duty. The GS had been sitting for several years but I had seen it perform and I new the motor ripped. I had about 2 weeks to whip it into shape. I entered a AHRMA ISDT Qualifier and the bike worked super until I stuck the motor. So I had less than one day on the bike and I killed it.

This is what the bike looked like when I first brought it home:



Since then I've had the motor rebuilt, frame painted and the Fox Shocks restored. So this spring is the assembly and hopefully a new life for the old girl. While not as sexy looking as a Husky, the bike is a performer even with me at the controls.

==================

From GreatestGeneration:

vintage Husqvarna that is stuck can be a bit scary. They had Magnesium cases and they are known to get Gut Rot bellow the Crank if Moister has been sitting there long enough. Some times so bad that a hole can be seen buy just looking at the bottom of the motor where the case seem is. Although the European bikes were not known to get to the first corner first compared to the Japanese bikes today they are known for having a great power band for those of us at an advanced age. Café-Husky's Left Kicker is a wealth of info, and Husqvarna-Parts.com make parts buying easy.


==================

From Scootern29:

Thought I would check in on your build thread and lo and behold you bought a Hooskvarna. That is a really cool bike as I have one in my shed waiting to be finished. This example is a 78 CR with the larger forks from the later models which is a direct bolt on. The motor is a 1980 412cc. The Curnutts are set for my riding weight.

The CR's came with Girlings from my recollection, but you could upgrade to Ohlins for some xtra dollars if I remember correctly.

Curnutts came on the OR models as the marketing was for what the team Husky off road guys were using at the time. Some people liked them and some people didn't. The main problem was, and is, that the shocks that were put on the bikes the target weight of the average rider was 175lbs. Curnutts were designed to be set up for individual riders and this was a drastic step in my opinion of what Charles beliefs were.

They were tested extensively by the Husky guys for this model. I was fortunate enough to be able to go out and help test at the time. We had a test track by the shop that had a little bit of everything you could throw at the bikes to dial them in. Another little tid bit is that the shocks the factory guys were running were not brand new out of the box stuff. They were actually used parts as we knew they wouldn't fail. These shocks were also not the original floating valve design of the earlier models. These were the bypass (pin) shocks that could be tuned in many different way's internally. I still have a bunch of parts and rebuild them for quite a few of the vintage guys.

As this is my 1st time cracking the cases on a vintage Husky I thought I better take lots of photos from various angle for future reference. Especially as I found the transmission to be somewhat fiddly as compared to the YZ465/490's.


Keep in mind that all this is on the '78 390. This should be the same as the 250's of the same era but I am not at all sure about the 430 as I believe these received a fair amount of updates. With that said, lets move ahead!

So like the Yamahas, there is a countershaft and clutch shaft but in this case there are 6-speeds instead of the YZ465's 5-speed (or YZ490 4-speed). Shift forks appear to be steel as opposed to alloy on the yamaha's.



The shift drum "detent" mechanism is resides inside the gearbox. You can see the locating lever, lever spring and front fork all share the same shaft.Yamaha places the corresponding mechanism under the clutch basket and outside the gearbox.




Each shift fork has a pin that rides in the shift drum as is usualy the case. However the pins have steel collars on them. Keep an eye on these as you dont want to loose them as you pull the transmission assembly from the case.
(BTW, using a little grease worked fine in holding these little collars to the pins when re-assembling.)

Now, you cant see it in this photo but the other side of the shift drum has a gear on it.
The shift drum gear meshes with the gear shown at the bottom of photo. This same gear is rotated by the shift shaft mechanism (not shown yet). It only rotates when making a gear shift so is never really under stress and requires no bearing. It rides directly on the shift shaft that passes through it.

When reassembling, it is important to get this gear positioined correctly. This is done by observing the number of gear teeth that are "uncovered" by the shift drum. One tooth should be exposed at the bottom of the gear and two teeth should be exposed at the top.





When I split the cases, the shift shaft stayed in the right side case. The next photo shows what it looks like. That pawl is part of the mechanism and sits on that pin.



This next photo shows the shift shaft, the pawl and a detent pin that is pointed at one end. The other end of the detent pin has a hole for a spring.





To the left of the gear is a hole in the case that accepts the detent spring and the pin. The pawl goes on the shift shaft pin and the shaft, with the pawl, must be flipped over and inserted though the gear. The detent spring and pin must already be in the case before the shift shaft is inserted.

Here is another view with the pawl and shift shaft ready to go back in . Again, the detent pin & spring is already sitting in the case. Yes, it's all very fiddly:eek1, but it can be done!




Here is a nice photo found on the web showing the individual parts making up the shifting mechanism. In this view you can see the gear on the back of the shift drum as was discussed above. That drum gear is rotated by the gear in the upper right when making a shift. Also shown are the shift forks, the 3 pin collars, the pawl with detent pin and spring, the shift shaft, the drum locator lever with spring and the shift fork shaft.



So I've focused on the gearbox in this post but I also had plenty of issues with the cases and crank. I'll put those details in a future post.

More to come!

As already mentioned, the crank case on this bike was filled with what looked like the remains of dried up fuel. I am guessing that this bike had been put into storage with the fuel still in the tank, and over time, that wound up overflowing the carb and filling the case.

It was really quite a mess. So much so that the semi hardened fuel kept the crank from turning over. It took several soakings with WD40 to loosen things up enough to turn the crank through a full 360 degrees.

This photo below shows the right side case. Aside from the expected crud, notice the double row crank bearing. The crank seal is on the other side behind the ignition. This right side seal is easily changed even with the motor assembled.



Although it wasn't pretty, I though all would clean up after a little work with a wire brush. And that was generally true for the right side case shown.

The left side case was another matter. It didn't take long to realize there was considerable corrosion to the magnesium. It was so bad I turned to a drill mounted wire wheel to work through it.

This next series of pictures of the left case tells the story...yes, a severe case of the dreaded Husky case rot... rats!

As you can see, there is a lot of corrosion at the bottom (6 o'clock) of the crank circle. And after picking away at the corrosion at 7 o'clock a hole opened up that goes right through to the gear box!




The screw driver shows the problem quit clearly! Notice that unlike the right side, the left case has the seal on the inside. Of course this means that the left side crank seal cannot be changed without splitting the cases.



And now that same hole but this time the view is from the gear box side.



I thought about trying to weld the hole and corroded areas but already know how tricky magnesium is to weld even when it is clean and in good shape. I just didn't have confidence that I could get a good repair given the extent of the corrosion I was seeing.

The only thing to do was to find a good set of replacement cases.


So I did .

More to come...

Alright, so it's been a rather rough start on this old Husky. I mean a bad crank and now bad cases too... jeeze!

Regarding the crank, my 1st thought was to buy a rod kit and rebuild the one I have. But rods for these things aren't so readily available. When you do find one they're fricken expensive, upwards of $400!

So then I looked for a used crank. I bought one "excellent condition" crank off ebay that turned out to be a real piece of crap. Fortunately I was able to return it for a refund although I did have to eat the return shipping.

Eventually I found a really, really nice crank for $200 (ha, that would get you 3 or 4 yz465/490 cranks!).

The cases were a little easier to find. $75 got me a pretty nice set. Although they were pretty nice, the right side case still had a few areas of very light corrosion. I'm finding this to be a common problem with old neglected Huskys.

Anyway, I cleaned the cases thourougly and then filled the few remaining lightly pitted areas with JB weld epoxy. This was to seal the pits in order to prevent any further corrosion.

This JB skimmed area is shown at the 4-5 O'clock position in the following photo.



The next step was to install a new crank bearing, crank seal and cleaned up transmission assembly into the "new" left hand case.

Fortunately, the transmission itself was in near new condition. In fact, I don't think this bike has really seen that much abuse. I believe the case and crank damage was simply a result of sitting a very long time with old fuel (together with condensation) in the crank case.



And now the crank goes in. As in some of the Yamaha rebuilds, I drew the crank through the crank bearing by tightening the crank gear nut against a stack up of spacers and sockets. Here is the transmission assembly and crank fully assembled into the left hand case.




These Husky's also require a center gasket which went on next. I also used a light skim of blue permatex sealer on each gasket mating surface.

The crank must be drawn through the right hand main bearing as the right hand case is mated to the rest of the engine. Once again various combinations of spacers and sockets were stacked up to allow the crank to be pulled through the bearing as the (left hand theaded) flywheel nut was tightened. Care must be used to ensure the spacers/sockets donot impinge in the crank taper while drawing the two halfs together.

The counter shaft must also pass through it's corresponding bearing in the right hand case. This took nothing more than an occasional light tap with the rubber mallet.

Before closing up completely, it doesn't hurt to take a peek at that fiddly shift pawl mechanism to make sure everything is still in place. Here is a photo with the cases almost ready to close.



More to come...

OK, we last left off with assembly of the crank cases and all went pretty smoothly there once replacement cases and crank were found.

Next up is assembly of the left side of the motor, namely reassembly of the clutch basket and the crank gear.

Here is the 1st photo showing that operation,



It may be difficult to see but the end of the crank is tapered and not splined as seen in the yamaha's. There is a key that is not shown. With the key fitted, the crank gear is assembled onto the end of the shaft and a right hand threaded crank nut is used to hold it all together. The torque setting of the big nut is (will look this up). No washer is used between the gear and the nut.

Also shown is the clutch basket components. First on the clutch shaft is a large washer, then the needle bearing and then on go's the basket. The basket is held on by a snap ring rather than a clutch nut (as seen on the yz465's).



The needle bearing is a nice setup. The Yamaha's use a bronze bushing here. So I would score this one in favor of the Husky.

There are a couple of other things to notice from the photos.
- You can see the left side crank bearing runs in gear oil. So while it a pain to change the crank seal for this bearing (split the cases), the bearing is well lubricated and should last a long time.

- You and also see the shift shaft here (lower right). It is not splined for a shift lever. Instead, it has flats that intercept some additional shift mechanism located in the clutch cover.

- The transmission gear peeking through in the upper right side of the case intercepts the kick gear that is also located in the clutch cover. These (generally pre-1981) Huskys do not have primary kick. You have to put the transmission into neutral before kick starting them. You cannot simply pull in the clutch and kick them over like a yz465/490 or later Husky's. This is seen as a drawback if you should stall while racing because of the additional time it takes to put the bike in neutral. This would certainly be the case for 250's. But I often put my big bore yamahas into neutral before kicking anyway. Mostly to avoid even the lightest additional drag that could keep me from lighting up in a single kick. These days, energy conservation during a race is a big deal!

Anyway, it is interesting to see the different solutions used among manufactures and how they evolved over time.

More to come...