KTM 530 EXCR- More better!

[Yellow Pig]

I did the leak down test today and the rings are at 40%.

I have always been meticulous about my air filter and check the air boot between the filter and the carb everytime I clean it to make sure no dirt/dust has gotten through. I even run a filter skin 80% of the time. I'm pretty confident it was not dirt that did the rings in.



Looking on line for piston & ring kits I cannot find anything for a 2010 KTM 530 XC-W. The only hits I get are for 530 EXCR. I'm assuming they are the same engine/piston, but want to double check.

The Wossner pistons come in 3 sizes (94.96mm, 94.97mm & 94.98mm) depending on cylinder wear so I'll have to wait till I tear it down to order.

[Yellow Pig]

OK

Took the head off the bike and can't tell what is causing the oil consumption.

Have a look at these pics and tell me if you see anything wrong.


Cylinder looks great:



Compression ring looks good:



Oil ring looks good:



Do these valve stem seals look properly seated? Not sure about this one?
Intake side valves:



Exhaust side valves:



It's definitely burning oil, lots of buildup on the piston and the face of the valves.





The back side of the intake valves looks pretty gunked up leading me to thing the intake side valve stem seals are leaking?

[Yellow Pig]

Looks kind of like the valve seals to me. Now if it is the valve seals I'm I better off going a head and doing the wossner piston kit w/ the better oil rings and be done with it or just reuse the OEM piston and rings?

[KMC1]

I'm not a good one to give you any advice - not the best mecahnic you'll find.... but I just want to say thank for posting this up for us - ill be arching and learning from this thread!

[Stobie]

Originally Posted by Yellow Pig

Looks kind of like the valve seals to me. Now if it is the valve seals I'm I better off going a head and doing the wossner piston kit w/ the better oil rings and be done with it or just reuse the OEM piston and rings?

You've already got it apart. Wouldn't it suck to put it back together and still burn a crapload of oil? I would go ahead and replace the piston just to improve my chances of avoiding another teardown.

Besides, valve stem seals shouldn't affect your leak-down numbers, so the pressure is either getting by the valves themselves or the rings. The rings on the stock piston are known to be problematic.

I should point out that my previous comment, "especially at 100 hours" was not meant to imply that 100 hours is a lot. If you had said 200 hours, I probably would have said not to bother with the leak-down test, just go ahead and replace the piston if it's coming apart anyway.

[Stobie]

Oh yeah, I meant to way that my cylinder bore looked like that, too, at more than twice or maybe three times the hours. The out-of-roundness and taper were both less than 0.0005" (professionally measured by an engine machinist neighbor). I deglazed it with a dingleberry brush, and put it back together. Probably only 10 hours on the rebuild so far, but so far so good.

[Yellow Pig]

Did you go OEM or aftermarket piston kit?

[Stobie]

Originally Posted by Yellow Pig

Did you go OEM or aftermarket piston kit?

I went with the Vertex. The Wossner is also supposed to be really good. The OEM piston lists at over $400, and has the questionable ring design. The Vertex was a little over $200, the Wossner about $175. The Wossner and Vertex are both forged, and the stocker is cast.

I don't think anyone has any criticism for the quality of manufacture of the stock piston, but most experienced engine guys find the oil ring design to be wacky.

[jesusgatos]

Wossner is still not burning any oil in my 450 after 7000+ miles.

[Foot dragger]

Originally Posted by Yellow Pig

Did you go OEM or aftermarket piston kit?

Its fun to ask for advice on ADV,if it was me I would search for a really good KTM mechanic and have him look at the whole top end,you've gone to all the trouble of taking it apart,might as well get it done right.
You dont want to guess at it.

How much oil was it really going through? Were you measuring what came out at oil change or checking oil level through the window?Are you 100% sure the leakdown test was done right? People sometimes can mess that up if they dont do it all the time.
From here the ring gaps look nice and tight,bore looks perfect. Replacing a (probably) good piston/rings may be just tossing money away. Internet hype may say you need an aftermarket piston,many get along for a very long time on OEM parts,some even finish the Dakar race on them.

[Foot dragger]

Originally Posted by Stobie

Oh yeah, I meant to way that my cylinder bore looked like that, too, at more than twice or maybe three times the hours. The out-of-roundness and taper were both less than 0.0005" (professionally measured by an engine machinist neighbor). I deglazed it with a dingleberry brush, and put it back together. Probably only 10 hours onthe rebuild so far, but so far so good.

Im told by mechanics that a very quick pass with a diamond hone is the only thing to do with a sprayed/chrome bore. Nothing else will touch its ultra hard surface.
Anything more then 1 fast pass with a diamond hone will remove too much material.
Luckily my 2011 530 uses no oil. I know KTM has changed ring/piston design since 08 and and the 2011 is supposed to hold up well. Im hoping so. Its a fun bike!

[scottbc]

Originally Posted by Yellow Pig

Looks kind of like the valve seals to me. Now if it is the valve seals I'm I better off going a head and doing the wossner piston kit w/ the better oil rings and be done with it or just reuse the OEM piston and rings?

My 2009 EXC450 looked exactly the same at 175hrs and was sucking oil like a hungry baby at the bottle! It was an oil burner from new, KTM even put a new piston and rings in at 20hrs. I did the re & re but had Dave Hopkins (djh on KTMTalk) check the bore and go thru the head. Oh yea,my compreesion ring was in three pieces?

My bore was basicly perfect, just select the right size Wosner piston, size the rings and assemble. Dave feels that touching the bore is pointless (unless their damaged or out opf spec) on these plated cylinders.

Dave cleaned up and checked the head, installed new valve seals and opened up the oil pasage in the rocker arm.

My bike now starts and pulls great with no oil consumpion. It was the best $600.00 bucks that I have spent on a bike!

[Stobie]

Originally Posted by Foot dragger

Im told by mechanics that a very quick pass with a diamond hone is the only thing to do with a sprayed/chrome bore. Nothing else will touch its ultra hard surface.
Anything more then 1 fast pass with a diamond hone will remove too much material.
Luckily my 2011 530 uses no oil. I know KTM has changed ring/piston design since 08 and and the 2011 is supposed to hold up well. Im hoping so. Its a fun bike!

Yep, a diamond hone is necessary for finish sizing. I went with the recommendations of those who know more about it than I do. The brush cleaned up the bore without removing a measurable amount of material. Probably took some material off the brush, though. Rings seated very quickly, and the bike is very noticeably stronger-running.

I like my 530 a lot. It's a much better bike than I am a rider, but it's still not hard to ride. I had been out of the woods for 30 years, and was a little worried that the 530 might be too much; but I'm a big boy, and I also thought that something less powerful, although easier to ride, might get old as my "legs" came back. It turns out to be a really versatile, user-friendly bike that I'll never outgrow.

[Foot dragger]

Originally Posted by Stobie

Yep, a diamond hone is necessary for finish sizing. I went with the recommendations of those who know more about it than I do. The brush cleaned up the bore without removing a measurable amount of material. Probably took some material off the brush, though. Rings seated very quickly, and the bike is very noticeably stronger-running.

I like my 530 a lot. It's a much better bike than I am a rider, but it's still not hard to ride. I had been out of the woods for 30 years, and was a little worried that the 530 might be too much; but I'm a big boy, and I also thought that something less powerful, although easier to ride, might get old as my "legs" came back. It turns out to be a really versatile, user-friendly bike that I'll never outgrow.

Ive had faster bigger bore 4 stroke singles, but the 530 is a nice compromise of going like stink,yet being really easy to ride and handles sweet on singletrack or playing flattracker on fireroads. I still ride my 300 in the woods mostly,been on 2 strokes for too long to give em up. + the trails around here are mostly all tighter then tight. The 530 will go through them better then I thought though.

[TipsyMcStagger]

Fantastic thread! I searched through and I see some of you have changed to the CEV multifunction switch. For the time being, I'm okay with the large factory headlight/turn signal switch on my new-to-me '08 450 EXC-R, but I'd like to install a combo start/kill switch. Right now, it has a single start button and I have to turn the key off to kill the engine.

A few years back, I did a full street legal conversion on an '06 EXC using the euro components. I'm fairly certain I used part# 59011074100. If I recall, there are few combo switches that look similar but have different part numbers (59411074000, 59411074100 and 59411074200).

Can anyone verify which start/stop switch would be plug-n-play compatible with the '08?

Thanks!

Tipsy

59011074100