1978 390WR and OR

What are the differences between a 1978 390WR and a 390OR? I'm kinda looking for a bike like a 76-79 360 or 390, WR is my preference. There is an 390OR availble near by.

thanks,
Mark

The OR is in between the CR and WR just as the XC was later. The OR has CR length suspension with a hybrid semi-close ratio transmission. All you would have to do is shorten the suspension to WR length and put some lights on it and you basically have a WR.

Cool, thank you for the reply.

Is there a place I can download these brochures? The picture is just small enough that I can't make out the fine print. also, I tried to download from the tech and ref section. Not sure what I'm missing, but I can't get anything out of there either.

The wr is a wide ratio trans, the or has the 1st through 3rd is wide ratio and the 4th through 6th is a cr close ratio trans. With the wr you need to wring out each gear before you up shift the engine rpms need to be up. With the or tranny the cr upper gears keep the rpms up. I like the or tranny you have the best of both worlds. The 390 engine is one of the best engines Husqvarna ever designed. It has a larger power band.

When I worked at Husky I got one of the ported 390 cylinders that Goat Brekker used to race the Nationals. I put that in my Or and that was the best desert racing scoot I ever had!

There’s something special about the design of the 390 crankcase or stroke that’s unique to the late 70’s case. Maybe it’s the stroke or narrow crank. The 390 is very impressive. The 360/390/400/420/430 seem to be the same unique engine.

I believe OR's came with Curnutt shocks too... member ChayzedPilot used to work for Curnutt and can rebuild them.

I love the Curnutt's for the desert and trail riding I do.... they seem like they have no damping and are too soft when bouncing on the seat while parked... but when you ride they just WORK. Pretty much impossible to bottom them out and they hook up the rear wheel to the terrain great.

There is the rake difference in 1978. The WR and CR frames had the 29 deg rake but the OR was the start of the 30.5 deg rake

i probably wouldn't notice much difference. But, what would be the expected handling difference between the 29 and 30.5 degree rake?

Sharper turn in.

which one turns sharper?

29 is turns sharper than 30.5 but keep in mind that all frames from 79-83 used 30.5 degree rake so it works well, definitely not a big deal or they would have kept the 29 rake.

There is no benefit in the 78 OR frame for eastern offroad. The benefit of the 79 - 83 frames is that those frames were built for frame rigidity and longer suspension travel. I feel the best you can do on the ML frame is about 10" front and rear. The MM frames can handle 12" front and rear

For northeast trails I'd love like 36" of suspension travel. However, having the 10" of travel will probably be o-k as I'm kinda short and a slow rider to not put my feet down quite often.

From watching helmet cam videos on the Netra Vintage Hare Scramble, I think this 78 should be o-k. The Netra VHS tracks are set-up to be not so rough. Riding enduros might be a bit much as they tend to send you through the most challenging terrain they can find.
The situation is 3-4 years ago I had talked about the 73 450wr I have and haven't finished. Also, about having 3 frames to build from a 76, 77, and 79. Unfortunately, I don't have the time to build a bike out of a box of worn and rusted parts as I am currently spending time on a 69 Cougar restoration that I am trying to beat a deadline with, and the ongoing Victorian house restoration that will probably last me the rest of my life. Perhaps someday I could assemble a bike out of a box. For now, if I want to ride something vintage it's best to just buy a running bike. I'd prefer a 390WR but, the 390-OR is available and close enough to do what I want.

I happen to have 2 1978 frames with the non OR geometry as well as a 78 OR frame I cut the neck out of and I will mount a KX125 neck that will allow me to use anything I have available for a front end. I am building a 1978 390WR on the WR frame I have and the other is a 1978 390 Auto frame(same as 77 CR).

The 78 Auto frame does not have the WR center frame loop and I believe has the mount for full floating rear brake. This is the nicest 78 frame I have had. I got it on eBay in 2007 and was going to build an HL500 on it. If you are interested, I will trade the Auto frame for the 79 frame you have. PM me if interested.

The 79 frame is something I would like to keep for when the time comes that I do have time to put together a bike. It does seem like the one to use if I had to choose.

How long is the stock suspension travel on the 78 OR? If it's less than 10", what is the method of getting 10" travel? For Netra vintage hare scramble, what is the best rear suspension to put on a 78 390-OR?