570 pistons / changes in 2009 vs. 2010+

Hi all,

There has been some discussion recently about model-year differences in the sloper bikes. Around the net the 2009 model is specified as having 11.8:1 compression and 2010+ as having 12.2:1. I have a '10 bike - in the 2010 owner's manual the compression is clearly specified as 11.8:1 ... BUT ... I dug up the engine spare parts manuals for the different years and compared. There is a different piston in the 2009 bike than the other years: 81730007100 vs. 81730007200. The 200 type is in the 2010 and 2012 engine parts books.

So I guess that's where the higher compression comes from. (Incidentally, the engine specs in the 2012 manual also specify 11.8:1, which can't be true, so I'm assuming that the compression figure in the 2010+ manuals was simply overlooked and not updated.)

If I check parts dealers, they say that the 100 type piston has been superseded by the 200 type: http://www.ktm-parts.com/search.html?q= ... +I&x=0&y=0

Two things I'm mildly curious about: There are two different sub-versions of the piston shown in the manual: 81730007200 I and 81730007200 II. Both the '09 100 and '10+ 200 type pistons have these two different designations. Howver, I haven't found any info about the difference. I'm guessing they could be a fraction of a millimeter different to fit the measured bore?

Just found this post: "On the AMS, Gear4 and Jim Aim website they all state group 1 & 2 piston kits! -- Spoke to Jim Aim today and they said that group 1 is for bikes on low hours and after the bike has done about 100 hours you go to group 2 as this has slightly bigger rings to cater for the wear and tear previously!?!?!" http://forums.mxtrax.co.uk/showthread.p ... ston-Group ... note that that thread is about a 250 2-stroke though. Still, I'm satisfied with the conclusion.

Hmm, hey, I just noticed that in addition to the piston change, the crankshaft also has a different part number: 81730018300 vs. 81730018400. The online parts fiches indicate that the 300 is used in 2009 bieks and the 400 in 2010-2012. I wonder what the difference is. Could the compression increase come with the new crankshaft? Can we tell by what we know? The conrod is the same, fwiw.

I have been wondering the same things and havent found the answers. the piston rings are different also. Someday I will need a new top end, and trying to decide what piston to buy. the 09 piston rings are the same part numbers as a KTM 560 SMR

Well guys I wouldn't worry about oem pistons when cp offers a hi comp forged piston kit at a lower price

I and II designates sizes, I have a std 570 09 piston maybe someone could measure, weigh and photograph a later piston for comparison.

Your workshop manual will give the size differences between I and II pistons I can't remember atm.

berglsmerg said:

Well guys I wouldn't worry about oem pistons when cp offers a hi comp forged piston kit at a lower price

I and II designates sizes, I have a std 570 09 piston maybe someone could measure, weigh and photograph a later piston for comparison.

Your workshop manual will give the size differences between I and II pistons I can't remember atm.

Click to expand...

Nice - do you know, does the CP piston work on 95 EUR octane pump gas?

Not sure I want a high comp piston either. How high is it? 13.5:1?

Hi Dave, I think the cp is in that range, compression depends on deck height, chamber volume, and HG thickness. I will be running 1.1 mm squish which will make high compression and detonation will be mitigated by the quench provided by the tight squish number. So in answer to your question tourist, I would say yes, I have run cp and wiesco hi comp pistons in a number of bikes with good results on crap Aussie fuel.

Now if I could get some bloody time away from work I will cc my motor with std, 100mm cp and 104mm cp pistons I have.

Not sure how bad crap Aussie fuel is but I'd like to take my berg to baja so I think stock compression is best. Any knowledge of the wossner piston?


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berglsmerg said:

Well guys I wouldn't worry about oem pistons when cp offers a hi comp forged piston kit at a lower price

I and II designates sizes, I have a std 570 09 piston maybe someone could measure, weigh and photograph a later piston for comparison.

Your workshop manual will give the size differences between I and II pistons I can't remember atm.

Click to expand...

according to wossner the 09 570 piston has the same specs as the 08 650 piston

deck height form center of pin to crown top is 24.5mm

piston volume = minus 10cc (dished)

weight 278 gm ..

i think that's the same specs you sent me from yours a while back mat?

you'd have to check the valve pocket reliefs but ktm 560 piston should fit and it has a piston volume of zero.

Id like to know more about the hicomp CP pistons for the 570 since they should also fit the 650.

bushmechanic said:

berglsmerg said:

Well guys I wouldn't worry about oem pistons when cp offers a hi comp forged piston kit at a lower price

I and II designates sizes, I have a std 570 09 piston maybe someone could measure, weigh and photograph a later piston for comparison.

Your workshop manual will give the size differences between I and II pistons I can't remember atm.

Click to expand...

according to wossner the 09 570 piston has the same specs as the 08 650 piston

deck height form center of pin to crown top is 24.5mm

piston volume = minus 10cc (dished)

weight 278 gm ..

i think that's the same specs you sent me from yours a while back mat?

you'd have to check the valve pocket reliefs but ktm 560 piston should fit and it has a piston volume of zero.

Id like to know more about the hicomp CP pistons for the 570 since they should also fit the 650.

Click to expand...

Yea sounds about right mate.

Dude I'm in the airport now on my way home, I've got Australia day off and then back into work. I'll try to get it done for you tomorrow. What size is the wrist pin on the 560 piston, found the hard way that ktm and +09 berg are .040" different, ( berg is bigger )

I can tell you that the cp 570 piston is dished.

ah happy Australia day "observation" Dude!

the 2014 wossner catlog is out

the 8583 piston is now listed for the sxs540 not the 560

20mm pin + 0.8cc piston volume wossner told me 300gm

another to consider is the 8593 with a 24.3mm height and + 9cc volume .. would probably need machining

the specific 570 piston specs 8737 are 24.5mm height, -10.5cc volume 11.8:1 cr 278gm

the pin part number is the same for all these pistons WP 038 wossner reckons 60gm for the pin

FWIW the CP 20mm pins I have seen are closer to 80gm

http://wossneronline.com/2014_wossoner_ ... atalog.pdf

this means you can also consider the 650 Pro-X piston and the ELKO OEM 628 piston for the 570 the pro-x is the cheapest

The 8593, I would take the lump old the top that would bump static comp up but still give good quench according to the piston height numbers ? Be good with a stinky cam.


Off I meant off FFS, fuggin iPhones :roll: Also 2500km in a truck and trailer ( 1500 miles in an 18 wheeler for
our American friends ) on busted arse outback roads has left me with new bruises and a fried brain.

dunno about the 8593, generally people prefer flat top or dished, some big lumps on top of the piston is the other way to go.

I don't think id do that unless I had to in order to make up for putting a huge cam in

Ha ha ha my edit also included a comment re stinky cam, went for a shower and didn't refresh the page.

berglsmerg said:

Ha ha ha my edit also included a comment re stinky cam, went for a shower and didn't refresh the page.

Click to expand...

the stinky cam made complete sense to me! scarier, more bite, better. like cheese. advanced cheese. right?

Ha ha ha Tourist, that's a good analogy, stink cheese with more duration and late intake valve closing.

aweswome !

so the wossner 8583 is like the high comp CP on left but in total its 25gm lighter (with the pin)

even though the wossner specs a pist volume of zero it clearly doesn't account for the valve pockets

Well the budget conscious choice for a rev happy build would be the 8583 then.

And we still haven't determined the differences between the 09 and 10 pistons :lol:

The cp hi comp 100mm is advertised as 13.5:1

No advertised comp for the 104mm but with chamber 34cc 9cc dish 610cc swept area and 8 cc for the HG assuming Zero deck height I'm looking at 11.9:1.

I think I need the 610 piston! :twisted:

Dave1867 said:

I think I need the 610 piston! :twisted:

Click to expand...

Yes I can personally vouch for the entertainment value. More fun than a barrel of monkeys.