250-500cc Wr 360 squish help

i have an 87 CR250 that is totally stock, replaced the ring out of concern but it was Ok as it was

Yi only got one at the moment but im going to keep a look out for 200 yammy and an 88 250 now.

any of the liquid cooled swedes are super strong if maintained. go easy and find top dead when you kick. feed it clean air and give it plenty of fuel and it may outlive you dog. i dont really race but my stuff sees plenty of pinned in 1st or 2nd hillclimbs...ive always let my 2 strokes warm up before getting on them hard and i think that helps them last. castor oil helps too, lol

I dont mean to start a "which oil" thread but my friends WR has survived on little more than Castrol Power 1 Racing fully synthetic. I mean little more, all he does is clean the air filter and flogs the guts out of it. We have to run it in these motors because everything else including Yamaha 2T racing oil fouls the plug in a tank or two

yep Castrol here too. cheap & decent full syn that's blue for ez id. sorry back to squish talk.

http://slavensracing.com/shop/slavens-mule-high-compression-component-cylinder-head-by-s3/ also found vhm but no wrs listed anyone used these?
Ive bored out the exhaust header as with the head off could clearly see the edge protruding into the outlet so blended that to correct size, more flow.
Looking at adjustable heads am taking it down to 55 thou on several guys reccomendations thats just off the head so i will be recessing the combustion chamber into the cylinder.
Will post pics basically im not stressed if this doesnt work as i can make the squish larger with thicker base gaskets this will also open up port duration a little bit...

So no one here has changed the squish in their bikes? How come?

i didnt want to alter my squish as i was unfamiliar with the 360 when i built mine so i just set it to stock. i did do the reed stuffer mod tho. i matched the exhaust as well

someone here should put a thread together, find the posts that deal with the modifications of the 360, and compare to stock if possible, would be a pretty good read,,, well for me anyway

Matched exhaust and pm'd wally for his thread a few years ago all good got the bike well dialed in apart from squish i want the puppy to be on top form so all the down falls are my own lack of skill, like the thread idea of 360 mods

On my 2002 wr360 the compression ratio (as manual names it) is 1,8mm, but if "justintendo" has the actual '94 manual and says 2,6mm then that is the correct squish band. As far as can understand though your bike has a ratio of 2,73mm. This seems to me like you have used some other piston that is approximately the same as for your bike , but not the right(just a thought).

A lot of piston manufacturers do this mistake and say that a piston or connecting rod is the same for 1992-2003 models but this is not always correct.

It's all good, I use the wossner piston for my bike the squish was set at 55 thou if I remember correctly.
She pulls like a train.
Has been through a piston since at 140 hours and a few sets of rings.

The manual specs ment that the squish wasn't actually doing much.
I've a huge bottom end lug and screams up an over 80 mph easy.

I recently bought member, Torben45's 2002 360WR that he completely rebuilt. He had the squish set to 1.8mm (.070") and CC'd the dome to remove a bit of material to keep the compression ratio reasonable. Bike starts easily for me although it takes a bigger boot than my '93 360, which needs a new top-end, due to low compression. I'm still debating what I will do with the '93. Thinking of shaving the head a bit, .070" seems reasonable to me at the moment though...

Just skim the head then put that on the 93 or the 02.
I'm running a 93 jug on mine it's much much better than the 02 will ever be.

Ya, I've been thinking of picking up another 93 cylinder because even with everything that has been done to the 2002, I still prefer the power delivery of the '93 in a major way. The 93 has such a friendly, wide spread of generous power, while the 2002 is very concentrated. The 93 just seems smoother, while still being very fast.

while I agree with your power band assessment, throw a Lectron on the 2002 and you might be shocked at the delivery difference
that said all things being equal, I like my 360 power as smooth and doesn't need as much compression to achieve the same power
that means it uses more 2 stroke dynamic power

Ya 2premo, the 2002 360 came with a Lectron when I purchased it. When I got the bike, it was a real handful for me in the woods. It was geared 14-52 and was running rich on the bottom end, then would abruptly clean up and made for quite a "hit" in the powerband. I changed to 15-52 gearing and put in a different metering rod in the Lectron and that made it into a different bike - much better for me! and the suspension and handling of my '02 are phenomenal with the 50mm works forks and Ohlin's shock. However, it still is not a friendly power delivery like my 1993 360. It is all low-mid punch and is somehow less appealing even though it is hard to explain. The '93 feels like a big bore, just a very friendly big bore, where the '02 is still more concentrated in delivery. Maybe it is that the higher compression of the '02 is partially to blame? I don't know, but I have read on here that a number of members feel the later model 360s aren't quite up to the standards set by the older models due to different porting specs from the factory on the Nikisil Cylinders vs. the Cast Iron liner in the older 360s. I tend to share that opinion at the moment.. By the way, do you still have a cylinder head off of the 360 you are parting out? I tried to send you a PM but I'm not sure it came through. I am looking for a 360 head with the head stay since the frame on my newer bike has the mounts for that. Plus, it will help me better understand how the compression changes things if I bolt on an uncut head.. Then I can decide whether to use heads with the squish mod or not.. Thanks as always for the input guys!

Yeah I've got a lectron an the 02 was all bottom and mid the leccy woke up the top slightly.

The 93 with lectron full fat psychobilly when in sixth tapped out she just pulls and pulls eats up fire roads so fast.
I'm only putting the 02 back on when the 93 is being re plated.

There's a load of pictures on here about power valve sizes the 93's are massive In comparison to the 02's.
The exhaust ports higher and wider also the transfer ports are bigger on the 93 it was a better tuned cylinder not sure who was responsible for working the 02 but torque isn't the be all and end all.

Workable power everywhere is tho.

93+lectron = keep bike for life!

I have a 95 top and it's the same as the 93, if you're interested let me know

What state is it in mate does it need re plating?