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April 8th, 2008, 12:53 PM   #11
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Originally Posted by popup
1. for instance if i adjusted my squish to .040" or 1mm (2.4mm off what i got now) i recon i would have to be at great risk of detonation, would't i ?

2. dr c , enginehardware was telling us that elko pistons are the lightest.
1. Improper design of the combustion chamber (given the fuel is burning at "normal" speeds) is causing detonation much more likely than just tiny squish. Sharp edges at the piston top can fx cause very lokal detonation problems. Don´t worry Weeds, the squish areas in a Husaberg are not that wide/deep that it will get you in trouble. -Tune away!

2. Yes, the Elko piston is very light and gives an almost good squish. It is however not lasting very long, or providing a decent geometric compression ratio.
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April 8th, 2008, 03:10 PM   #12
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as said, wrong about the chain.

to check the real compression you need to remove the head, get the piston to TDC, smear vaso into the gap twixt piston and linar. headgasket, head on, lightly torque, place engine slightly over so plug hole is highest point, use a syringe to squirt in paraffin or similar. stop as the paraffin enters the plug thread.

if say 64cc you have to add that to the engine size which is either 644 or 628. 644 + 64 =708 and then divide by 64 so you get 11.06 to 1 compression.

to get the area you would gain which i take to be 2.4mm of the swept volume it is:
pie r squared x radius x radius x 2.4
3.142 x 50 x 50 x 2.4= 18.85cc

so you know that 64cc would become 45cc of paraffin etc etc.

so 644 + 45 = 689 divided by 45 for 15.31 to 1 compression.

but as Dr C would tell you, you would machine around the inlets and then do a bit to have secondary squish and then we have to machine big recesses in the piston coz you are now 2.4mm nearer. so you'd be amazed how hard it is to get a really high compression.

i hope you found this useful.

trust you have the 35mm big end?

regards

Taffy
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April 8th, 2008, 10:44 PM   #13
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all good info lads,even if i will never use it.maybe someone else will.
when a 450 beats my old girl in drag race then maybe....can't see that happening
..weed..
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April 8th, 2008, 11:00 PM   #14
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is that all you can say? a shekel for me life story?

how about a penny for an ex-leper?

regards

Taffy
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August 26th, 2017, 10:09 AM   #15
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Hey Guys,

Did we ever come up with a high quality, light and durable high compression piston option for the 04-08 650?

Thanks!
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August 26th, 2017, 02:04 PM   #16
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How high do you need ?

For standard Comp 05-08 can use Wossner 570 piston in backwards

The compression ratio and squish spec are the same as oem elko but the shape of the 570 piston is not ideal imho.

Use oem (price is ok) Or for higher Comp get the Ktm 540/560 Wossner piston and machine the top down to what you need.

Pro x is cheap shit I got 100 hours out of one.
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August 27th, 2017, 01:34 AM   #17
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Originally Posted by Big Berg View Post
Hey Guys,

Did we ever come up with a high quality, light and durable high compression piston option for the 04-08 650?

Thanks!
well I sell one! i call it the 'tall boy'. OEM is really good quality.

regards

Taffy
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