250-500cc 2012 WR360 Project

[msmith345]

The project bikes forum is apparently all reserved for vintage bikes. So, you all get to see this on the 2 strokes forum instead.

Scroll to the bottom of this post for the parts required. I'll update it as this project progresses, in case anyone wants to give the swap a go. Others have done it, but I figured I'd do my own write up.

Back Story

A few weeks ago I found myself in need of a complete rebuild on my 2012 WR300. I didn't have the time to rebuild it to my satisfaction, and still be able to finish out the racing season. So, I looked for a cheap 250 two stroke to let me finish it out old school. Well, in my searching I found a 1992 WR360 for the right price at only a 4 hour (each way) drive.

Here's just a random "before" picture of the WR300. Love the bike, and I will rebuild the 300 engine -- with the extra 6 speed transmission.

And here is the "new" donor bike.

PARTS REQUIRED (for my bike to bike swap)
1. 1992 Airbox boot onto the 2012 airbox. Part number on the 1992 matches the 2000-2012 WR360 [8A00 69546]. So, it is a direct swap from bike to bike. Works awesome.
2. '00-02 WR360 Headstays ? (The 2001 and 2002 Husky part catalogs do not list separate part numbers between the 250/300 and 360.) If the 2012 ones do not fit, I'll include something in a post below to show how I made my own. The 1992 head does not have a headstay mount.
3. '00-02 Exhaust - 1992 has a unique exhaust flange (inside the pipe rather than outside). It fits the frame fine, however the 360 silencer also needs to be used. I have what appears to be a universal turbine core on there with a bracket I can move around. The 2012 silencers can not be used as the stinger angle is dramatically different.
4. Custom clutch cable - Essentially, I'm needing a Motion Pro #10-0154, with a 90 degree bend to clear the coolant hose. In the mean time, I swapped the bend from the 1992 cable onto the 2012 cable, cutting down the sleeve a bit to compensate for the added length.

I'll update this list with the complete list of what's needed for the conversion as I progress.

 

[wallybean]

You can use 2000-02 parts for the swap. The FMF Gnarly adds even more punch. You will want to make some changes to the reed stuffer and carb boot on the engine side so you can get some more rev's. The head stays are different and there should be a designation for just the WR360. You might want to see if the air boot off the 92 will work in your '12. I would think it would be close.

 

[2premo]

if it really is a 92 you will find the pipe is a different outlet on the exhaust port, the pipe fits over the port not in it
if the pipe is a gnarly re-use it

 

[msmith345]

Excellent tips guys. I found parts catalogs for 2002 ans the 1992 on Hall's site (http://www.halls-cycles.com/default.asp?page=catalogs) the Husqvarna NA site was missing both.

The airbox to carb boot on the 1992 and the 2002 are the same part number, 8A00 69546. Adding that to the list in the first post.

The 2002 parts catalog does not list a separate headstay for the 360 and the 250/300. Only a part number of 8000 69434 is listed, and it is not distinguished for one or the other. So, I suppose if it does not fit, I'll just make my own.

On the exhaust, now that I have the parts catalog, I see what you mean. Anyone happen to have an idea on if the '92 pipe will fit a new frame?

 

[Chef]

You might have trouble finding an fmf gnarly for an 02. I was looking for one for my cr250 and fmf doesn't list them anymore. I found one that someone had in stock. I was surprised when they told me the later models wouldn't fit on my 02.

 

[2premo]

Excellent tips guys. I found parts catalogs for 2002 ans the 1992 on Hall's site (http://www.halls-cycles.com/default.asp?page=catalogs) the Husqvarna NA site was missing both.

The airbox to carb boot on the 1992 and the 2002 are the same part number, 8A00 69546. Adding that to the list in the first post.

The 2002 parts catalog does not list a separate headstay for the 360 and the 250/300. Only a part number of 8000 69434 is listed, and it is not distinguished for one or the other. So, I suppose if it does not fit, I'll just make my own.

On the exhaust, now that I have the parts catalog, I see what you mean. Anyone happen to have an idea on if the '92 pipe will fit a new frame?

on the pipe issue, put the engine in the frame and try it, my 93 and 99 are similar enough that a twist of a mount can be all that is needed, you might have to weld a tab on or in the worst case you might need to migrate the header over to a newer 360 pipe and the point is you are not doing stock so like the head stay you might be making a part, by the way my 92 360 did not have the head stay bosses on the head but the mounting points were on the frame

 

[justintendo]

its the earlier 360s that had the pipe slip over right? i just got a dynoport for my 95 360 and has 93-95 engraved on it. it slips into the cylinder with an o ring

 

[2premo]

its the earlier 360s that had the pipe slip over right? i just got a dynoport for my 95 360 and has 93-95 engraved on it. it slips into the cylinder with an o ring

that is correct, only the 92 uses that style, hope someone replaced his top end as it will make the project easier

 

[msmith345]

You might have trouble finding an fmf gnarly for an 02. I was looking for one for my cr250 and fmf doesn't list them anymore. I found one that someone had in stock. I was surprised when they told me the later models wouldn't fit on my 02.

I'd be questioning that pretty hard. The DEP pipe I put on my 2012 is listed (now) as a 2000-2012 CR/WR250 pipe, at the time I bought it, they only had it listed to like a 2006 or something. It bolted right up with a Leo Vince sparky.


I've got an awesome problem that I'm going to have to take care of first. At this point I now have 4 bikes in my 1 car garage/workshop area. Along with that I have an assortment of Husky 250/300/360 bottom ends and assorted parts. So, I've got to spend the day organizing a bit. I'll plan on pulling the 300 engine out and start pulling the 360 apart, so I can get a better look at everything. Hopefully that means I should be able to test fit the 360/pipe combo tomorrow night. That way if I do need to order some parts I can get that place first thing Tuesday.

 

[juicypips]

errm whats wrong with the 360? just use that as it you will love it!!

 

[msmith345]

The 360 isn't in any shape to last a 100 mile enduro. I could spend about $500 getting it race ready without tuning in he suspension. Or I could do the engine swap into the frame I already have suspension tuned up, all the necessary armored bits, and all the ergonomics I want. Pretty easy choice.

 

[msmith345]

Ok, garage is organized and I got a closer look at the 360. Almost have the 300 out of the frame, but realized I'm missing a 22mm socket. So, I'll have to pick up one after some grubbage.

Some findings:
It is in fast a 1992 with the 1992 cylinder/internal flange setup. So, we'll see how the '92 pipe fits in the new frame.

The head does NOT have a headstay mount. So, I will not have to worry about fitting one.

 

[justintendo]

errm whats wrong with the 360? just use that as it you will love it!!

lol, i was thinking that too...bike looks pretty good...if i lived closer, i would ask about buying that chassis

 

[msmith345]

That picture is very deceiving. Good from afar, far from good. Really the argument to race it as is completely ridiculous. It could be made into a trail rider beater, but it would not hold up to any serious riding without some major work. Even so, I've already stated the 2012 frame is all setup. Not lacking anything from a serious off road racing bike. Plus, I can still get Husky to pay me contingency to race the 2012...so, any argument you have is invalid. After I've rebuilt my 300, I'll put it back in the 2012 frame, and reassemble the 1992. Clean it up, and keep it around to race the Saturday harescrambles, they are only an hour long and a lot of people run vintage bikes on, as it's basically just for fun.

Made some progress today. Organized the garage, then proceeding to strip down the 300. Pulled the bottom end, and everything else that needed to be pulled. Going to do a serious cleaning on it tomorrow after work. No write up is needed for this, If you've never pulled an engine, it's really not complicated. Actually, up to this point, nothing has been bad at all.

After I finished up with that one, I put the 360 up on the stand and started on it. Time got away from me, and I ended up with this. You'll notice the Mikuni hanging there. I have no intention of using that carburetor, as I've got a 38mm Lectron ready to bolt on that I've been using and very much like.

This part was a piece of cake:

So, tomorrow after work. I'll get the 2012 frame all cleaned up and get the 360 dropped in place and start seeing how things are going to fit up. I did find some parts I do want to replace. The intake boot and the air box boot, mainly because they are 21 year old pieces of rubber and do have some weathering. They should hold up fine for a while, but I want to be careful with them and get something fresh in place as soon as I can.

 

[2premo]

don't forget to look at your powervalve movement and adjustment
and by the way the early TM carbs actually work pretty good, my later TMX is a disaster

 

[icebergstu]

Its a 92 - The most insane of all the 360's. They changed the PV in 93 to tame them down.

That's going to be awesome!

Stu

 

[K5PL5]

Man I started looking around for 360s now. You are a bad influence haha. This is a great thread but I cant stand the waiting haha

 

[lankydoug]

Man I started looking around for 360s now. You are a bad influence haha. This is a great thread but I cant stand the waiting haha

I'm thinking the same thing; 6 speed, big power and the newer chassis. It should be an awesome combo.

 

[msmith345]

Well, I've run into the first hiccup.

Everything was going great. I get the frame all super clean and degreased. Get it back on the stand, and drop the 360 in. It lines up perfect. Throw the two bolts through the mounts. Go to push the swingarm bolt through and clunk clunk...it's stuck. So, I get a bad feeling and pull the engine back out of the frame to check the bushings.

I had an '02 CR250 case sitting there, which fits the larger bolt. So, I had the idea I'd pop the bushings out and swap them. I obviously didn't look at it too close before going through all the effort. Because this is what they look like side by side. '92 on the left, '02 on the right.

So, I'm going to go back out in a bit and do some measuring and see what I can come up with.

Some options I see:
1. The 360 case with the bushings removed is only a bit larger than the bolt. So, it's possible that I could shim it up. I don't like the idea of that as if the shim slips, the cases would likely crack because of the vibrations.
2. I could (or find a machine shop to) drill out the cases to fit the larger bushing. This would make for an irreversible modification, which I didn't want to do. This could be resolved with turning a busing to match the outer of the larger bushing and the inner size of the old bushing.
3. Get a bushing turned that would essentially be a super thin shim. Not sure the measurements support that or not.

 

[2premo]

for sure you need the bushings, they are what you torque not the cases
a thought a paper thin one will fail for sure,
bore out the cases, use your 02 bushings and have an adapter made to reinstall,, if you do,, in the 92 chassis