250-500cc WR360 rebuild...

Gudday...
Just need to pick the collective knowledge base for some info please?
I 'popped' the top off the 2000 model wr360 yesterday for a look.... It's running fine but a little noisy, so I thought I'd look.
Hopefully the following pics will be OK for diagnosis... Is the nikasil bore stuffed?? It's a 'B' piston in there... What do I do? Stick a new B piston in or get the cylinder repaired and sized to suit?? That'd be EXPENSIVE like nearly 1000 bucks AUD.... It seems to me there is an infinite amount of size variations with piston, wrist pin and con rod.. What's everyone else do?? There are no scores or anything in the bore but it's def. looking used...















Regards
FBC

What oil are you using? I replaced the piston and rings last winter and it was the original piston. It was almost in specs and I had none of the wear or carbon build up that I see in yours.

I would measure the piston for tolerance in the cylinder. If it is fine re-ring it and change oils to a full synthetic. It doesn't appear that you have any huge grooves in the coating and the minor wear lines aren't really a problem as long as you have a good set of rings. I use Amsoil Intercepter in my 360 and it is showing absolutely no wear marks in the cylinder and runs very clean with no power valve sticking. I ran mine with no coolant for many miles(oops) and had no metal transfer or grooving in the cylinder. I didn't even need to ring it afterwards. If you are seeing excessive wear on the piston you can always opt for a "c" or "d" piston depending on the measurements of your cylinder. Of course having your cylinder re-coated to stock specs is the safe way to go but very spendy considering there are no cheap pistons available for the 360.

Walt

I had to replate my cylinder to get it where I was happy with it.

I ordered the 'A' piston and had it plated to suit. I am very pleased with the results but it wasn't cheap. Hopefully now as it wears I can adjust clearance with slightly larger pistons.

The Husky (Wossner) piston although expensive, it is a very nice part.

Hey Walt!

I use Castrol TTS. Amsoil is not readily available in Australia but I will take your advice and switch to a full synthetic. I guess your right, I should just pull the barrel (jug) and measure up.... Sounds like a Friday night with friends job... :-)
Thanks
Shannon

Yeah.... :-)
I've gotta decide if a 1000 dollar repair is justifiable on a 2000 dollar motorcycle!!!

Hi there!
Great choice, the 360 Castrol TTS Power is a fully synthetic, and in my opinion, one of the best 2stroke oil around. API TC+; JASO FD; ISOL-EGD. I'd say your soot problem comes from something else.

About the con rod small end colour with various cage selection, as far as I know, most dealers* sell the standard 18x22x22(mm) cage. I've had no problems using that size (been riding 360 since 1996).

*in Sweden

Gudday!
Thanks mate. I've always used Castrol products in my bikes, except for the air filter oil which doesn't seem to stick too well. Thanks for the tip on cage selection, I'll do that. At least 9 different variations you can choose!!

I didn't look at it that way. I viewed it as spending money on a bike I can't buy new anymore!

In case you have the owners manual, here is some extra stuff from the service manual that might come in hand. Do note, that if you aim to order a Wössner piston, they don't use the same terminology. Husqvarna calls them A/B, C/D, E/F and Wössner A, B, C, 050.

This sometimes cause confusion, I ordered a "C/D" piston to my MY1996 and got a Wössner 8076DC which is 77.96mm! Fortunately, my MY1999 has a "E" which means the 8076DC is a perfect match!

Check out the pictures and the Wössner catalog and you'll see what I mean.

http://www.woessner-kolben.de/english/katalog/husqvarna.pdf

Fatboycrash,

Even if your piston has some scuffing, if it is within tolerances that are illustrated by Skyldig, just make sure the skirts are smooth, pop some new rings on it and go ride. Just use some 600 wet and dry and smooth out any ridges on the piston with very light pressure. If they are only grooved in then just lightly remove any sharp edges on the grooves and go. The tollerance of the skirt to the cylinder is the key gap with the top piston gap next. You just don't want that 2 lb wad of metal developing any side to side slapping motion.

Ps. Athena makes replacement pistons for the 360 and while slightly less money are not same quality as the Wossner piston.

Good luck,
Walt