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Discussion Starter · #6 ·
Hi Paul,

Yes, they are 1mm oversize stainless.

The head has been ported and smoothed.

This was done some years ago when it was on my '08.

Tom
 

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Most intriguing!

The displacement increase is about 4.3 %; however . . . the compression ratio is increased over 13%; don't know if it'll ever see a dynamometer, but I'd bet a robust power increase arises.

Pump premium gasoline and stock ignition timing ought to get along with no pinging, seems to me, because: 11.1:1 compression ratio is not unknown to some modern street engines.

Nothing wrong with the pumper CVK40; 50 million Harley riders (with pumper CV40s) can't be wrong! :)

Whose piston?

Following along with interest, Tom!
 

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Tom did or are you planning on smoothing out all ridges etc inside the combustion chamber? Don't know how many ponies it'll make but it was one thing I was directed to do....after the work it seems you have already done....what does the pots under your valves look like? How aggressive is your porting job? Did you do it or who? Heavier valve springs? I chopped down the hieght of my valve guides also to help reduce as much from the air/fuel passageways..... I wonder if you have pics of the porting work...? All very nosey stuff....lol
:stickpoke:
 

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I'm wondering if it is already too late for Tom to take pics of the oil return holes in the ring land and maybe any oiling holes in the piston pin boss?
Maybe measure the return hole size's?

We sure can be a demanding bunch, sorry Tom. We'll appreciate any and all info which is presented.
 
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Discussion Starter · #11 ·
Paul,

There are four oil return holes on each side that are 3mm ø.

There are no oil holes in the pin boss.

Here are some pictures. This is the Wossner 8523D200 102mm piston.









Tom
 
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Paul,

There are four oil return holes on each side that are 3mm ø.

There are no oil holes in the pin boss.

Here are some pictures. This is the Wossner 8523D200 102mm piston.



Tom
Pretty picture of Perfection!
Them are some fairly broad skirts compared to the JE skirts.
The oil ring groove looks to be as broad as the 87-07 pistons.
3mm holes ought to evacuate the excess oil.

'Sandstone' out of Chicago, I think, is running the Wossner.
 

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Yes those skiirts are what will make all the difference imho, over the last kits......it really makes one think about what if I......Damn you for posting those pics! Can't wait to hear the final opinion on it's benefits....then if that piston works really well, how big can you go....? AUGH...I'm going now before i have a meltdown!
 

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Discussion Starter · #15 ·
...'Sandstone' out of Chicago, I think, is running the Wossner.
Yes, he's using the 8523D100 piston that is a millimeter oversize and gives a displacement of 666cc.

I haven't talked to him, but it sounds like he's had good luck with it so far.

Any other dimensions you want off the piston? I hope to install it this weekend if Ray is around to offer a hand holding the jug while I insert the piston. Last time I did this I held the jug with one hand and used my other two hands to install the piston.

"It was awkward and I vowed not to do it single handed again", Tom fumbled.

Tom
 
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Discussion Starter · #17 ·
I have trouble remembering what I had for breakfast and can honestly say I don't remember that thread.

That said, I don't remember where I first heard of the Wössner pistons, either.

It is entirely conceivable (likely, in fact) that it was from that thread that a seed was planted.

Thus, in continuing logical the progression, anything that happens from this point forward is your fault, Damocles.

VBG,

Tom
 

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Discussion Starter · #20 ·
Paul reminded me that I've not been keeping up with this thread.

With the piston I bought a head and base gasket, both Cometic. The head gasket was a good idea as it was manufactured for the oversize bore.

I'm not fond of Cometic base gaskets as they tend to weep a bit, but if ya know that going in they can work so I figured I'd run with it.

Cometic has been making base gaskets for the KLR for a while; I put one on my 685 on my 2008, so that was back in 2011.

For some reason the gasket I got in Wössner's kit was under-size at 105mm vs 109mm. It wouldn't go over the liner. I ordered an OEM gasket as that is my preference over getting a properly sized Cometic. I let Wöessner know about the problem. I must have been the first to get their gasket kit.

That set me back quite a bit as it was back-ordered and it took all of a couple of weeks to get it.

I'm hoping good neighbor Ray will be around to help me drop the cylinder over the piston this weekend. That should put the bike up and running some time next week. I don't know if I'll get to break it in next week or not, and it looks like I'll be at Lake City Arsenal the following week.

The bike has been down since late February, but I've used the time to do some electrical work and build out a new, fully sealed, air box, go through the right side to make sure the balancer system is in good shape and properly timed, and wait two weeks for the head and cylinder to get done.

Most Curious.


Tom
 
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