Engine Swap?

Will a 1980 390OR fit 1979 250OR frame and will the 390 pipe fit a 250? Is it worth it to put the 390 engine in. The 250 runs perfect and is original. I just pickup an 82XC430frame with the 80 390OR engine with handmade conical pipe. I would like to use this pipe on my 250. Should I build a Hybrid and sell? The 430 is not practical as the bike is way too tall for me. My 250OR fits perfect.
Thanks

Engine will fit, pipe will not. Keep the 250 intact, and if you don't like the 430 sell it to fund your next 390 project. You won't be disappointed; the 390 is an awesome motor. Lots of frames around.......

The 80 has more suspension travel. You could raise the forks up higher in the tree and get shorter rear shocks? You can tune the suspension to the height you want.
The 430 and 390's are awesome motors. I have more miles on the 79cr 390. I enjoyed the hit and power of the 390's. I do like the 79 seat much better than the 82/83 flatter wider seat.

Have you ride the 390 yet? The power goes from the bottom to the top. I suggest you to take it slow at first the 390 is no 250. Just point the bike were you want to go and wick it and hang on.

Dido on lowering the bike, possibly use a wr suspension instead of xc. Change swing arm to the shorter wr and use wr rear shocks and then lower the front in the triples and you may like what you find.

That was one thought. Keep the engine and pipe. Sell the rolling chassis and find a 390 frame, but if the 430 and 390 frames are the same I can make a hybrid 390 with shorter swingarm. We do alot of single track woods and as much as I want a 390 it may be way too much in New England for me.

Where are the shock springs tentioned at? Preset?
My 250wr the shock springs are preloaded too much. I'm on my tip toes when I'm on the bike. I'm going to back off on the spring preload first. Example if we have 12" of travel we should have about 4" of race sag when your on the bike in full gear. We don't have too much to do but adjust the shock spring preload or get a lesser spring rate so we can dial it in properly.

The 390 OR will be a fun machine to ride in Mass. It's first three gears are wr, and the next three gears are cr. You can shift gears while climbing those hills on the pipeline while screaming up them. That 390 or was designed for mass. The torque is perfect for riding mass. Just wick it and burp it through the tight sections. You will love the 390.

Adjust the suspension to your liking and burn the tire off that torque monster.

There's a reason why my recent project bike is the 390/420.

Here's a picture of my hybrid: 1980 WR frame, 390 CR engine, 1984 WR forks and seat, early '70s tank. I'm going to replace the CR with an OR engine. That's the beauty of these bikes; build them the way you want them because so many parts will interchange.

I'd put the OR gears in the CR engine.

I talked with my old local husky dealer who also raced husqvarnas. And I told him how much I liked the 390cr over the 250, 400, 430 huskys. He agreed the 390 was one of the best husqvarna engines. The 250cr & 250 OR ran great power wise and the 430wr was a tractor in 83 a.c.. The 400 86 LC was in transformation yet but a very tractable power with the throttle, very smooth power. The 390 was like a wild night on the town.
When you wicked it you knew it was going to be a wild ride. There all great engines but I liked flying with no wings on the 390.

My '79 390cr had the same tank. So did my 80 390. My cobbled together 82 420 had the big diamond shaped purple silver sided tank. I regret selling them.

My project bike now is a 420 cylinder on a 430 crank in the me newer case with the larger transfer ports. It's a 430 most likely. But things can change. I have the 86/87 500cr front forks with disc brakes. If we race it I can swap out to drum brakes.

I think I am going to assemble the bike. Raise the forks and put a coffin tank 390CR tank on. I may look for a shorter swingarm if there is one to fit the 82 frame.

Measure your rear shocks if there 17.5" get the 15" shocks. Or move the swing arm brackets towards the rear.
I used the progressive Freon filled shocks, but with the correct springs for my weight. I had two bikes with these shocks with no problems. I feel if we run too light of a shock spring we can wear it out early. The shock has to be tuned to your weight with the correct spring tentioned. The progressive shocks need to be working in there comfort zone. Choosing the correct springs helps. Too weak of a spring, no good, too tight of a spring no good too. I purchased one 390 that had the 15" progressive shocks with the 17 1/2" springs. Me and my brother couldn't move the suspension. Let's face it even the twin shock suspension needs to be tuned to our weight and style of riding.

The WR swing arm is shorter than the XC/CR. If I was you I would not swap engines, all you have to do is set up your '82 430 chassis like an '82 WR. That will lower the seat height 2" and you will still have 10.6" of travel at both ends. Its a straight parts swap.

I have an '82 250XC that I set up for a 5'2" woman. All I had to do was put some '83 175WR forks on it and I replaced the original swing arm with a '79 WR swing arm with the top mount lower shock mount so I could use a pair of regular 14.5" shocks I already had around. This lowered it more than you would want, but it still got the seat height down to around 35" and the bike had 9" of travel at both ends. It was a simple parts swap.