Ducati.ms - The Ultimate Ducati Forum banner

1 - 14 of 14 Posts

·
Registered
Joined
·
9 Posts
Discussion Starter #1
The 2 compression rings for my 2001 m600 do not look like the ones on Haynes or workshop manual. They look identical (square) on the face that meets cylinder wall , but on the piston side there is a "step" on the other ring. The one without the step seems a bit stiffer and I think it should go on top, but from my disassembly pictures I found that the one with the step was on the top and the stiffer one under it. The reason I pulled cylinders was oily sludge on spark plugs, ring gap was huge (nearly 2 mm). New rings are from ducati and identical to the ones I took off, they are black and say k-top on the topside. So does anyone here know which way im supposed to install these? Duc catalog tells me the part I got is 12120232A, which has replaced 12120231A.
 

·
Premium Member
Joined
·
3,795 Posts
Yes I am not familiar with your specifit piston , brad should know if this is oem. Looks it to me.

Common for the stepped ring to go on top be sure to measure end gap on both but it looks standard to me. again someone who has seen the small bikes will be a better judge as they are nut common in the US. Belter should be right along to set us both straight.
 

·
Registered
Joined
·
9 Posts
Discussion Starter #7
Yes I am not familiar with your specifit piston , brad should know if this is oem. Looks it to me.

Common for the stepped ring to go on top be sure to measure end gap on both but it looks standard to me. again someone who has seen the small bikes will be a better judge as they are nut common in the US. Belter should be right along to set us both straight.
I called up all ducati service shops here and apparently im the first person in finland to change ducati m600 piston rings. Has to be done though, 120k kilometers on the clock and top (what I assume is top) ring gap was close to 2mm measured on the untouched end of the bore. Funny thing is I posted on some italian old monsters forum and even they were confused about these, the old style piston ring set has apparently been replaced by these at some point. Would save my whole winter if someone could confirm this. The weather here is looking like we might get snow till may, but the old duc has alot of maintenance left to be done. Last shop maintenance bills were from 80k and when I got the bike it was on 109k.
 

·
Premium Member
Joined
·
3,795 Posts
Lol.. ever think of dropping in a set of high compression pistons or a big bore? fresh pistons and rings.
Didn't Belter (brad the bike boy) hop up his 400/600? he may have a recipe of oem parts you could swap in and get you some extra for your effort.

Any reason to not install a set of 620 pistons and cylinders? I would think there would be cheap sets as there is not much call for them. I have a set of 750 pistons and cylinders on my 620 bottom end and it is a bot out of balance as well as needs the combustion chamber re-cut but has run fine on the track for the last 3-4 years. The 620 probably would not need a mod to the head as they are the same bore size though the stroke change may mean the wrist pin location is wrong.
 

·
Registered
Joined
·
9 Posts
Discussion Starter #9
Did consider it, BUT in europe we have 3 motorcycle licence stages and im on the second one. Still need to ride my "restricted" bike (35kw max) for 2 years till I can get the bigboy license. Im already on the grey area because I "lost" the restrictions on my way to norway last year and it would be just fine putting around finland and with some bigger barrels but im going to italy next summer and I think I might throw a lap around the ring in germany. From what I've heard they are very strict with the restrictions and the police likes to take plates for even minor imperfections with a bike. If the bike is running all fine in 2022 I'll get some aftermarket or bigger bores for sure. And yeah, im basically braking the law here being 22 and riding around with a stock m600 😂
 

·
Registered
Joined
·
9 Posts
Discussion Starter #11
Finnish police have a rolling dyno on them (just a small one to go under the rear wheel), rarely use it but they do. They can also see my reg which their computer searches automatically with my plate. Reg shows the kw and the restriction+ how the restriction is supposed to be installed on the bike. We do not have bike inspection yet but there have been rumors it might come. In some countries around europe your bike needs to pass yearly inspection in order to to ride it. Worst case scenario they take my license and plates, then I would have to convert the bike to complete stock and take it to inspection. I would just risk it If I didn't want to travel around other countries in europe. The police has already given me a hard time with the bike because "it doesnt sound a2". The sbk's dont really help, took it as a compliment though.

I've also heard some of the water and oil cooled ones can be fitted with some modifications, hard to come by here though. Im learning italian at the moment so I might pick up some cheap parts while in italy. Could a 900 engine be fitted to this frame? Used dry clutch monsters are usually around 10k in eur here while in italy you can pick up the engine in decent condition for around 400eur. Would likely have to do some major modifications though.
 

·
Registered
Joined
·
1,913 Posts
dunno. the reason i looked in the 620 manual is because they may have superceded parts from 600 to 620 in a spare parts efficiency move based on no reality at all. just in case the 620 were different.

the L top ring is called a dykes ring, and is not what you have - the L is much more pronounced.

does your stepped ring have a dot or "top" written that would have the step fitted to the top side? i'd call that the top ring. could be wrong.
 

·
Registered
Joined
·
9 Posts
Discussion Starter #13
dunno. the reason i looked in the 620 manual is because they may have superceded parts from 600 to 620 in a spare parts efficiency move based on no reality at all. just in case the 620 were different.

the L top ring is called a dykes ring, and is not what you have - the L is much more pronounced.

does your stepped ring have a dot or "top" written that would have the step fitted to the top side? i'd call that the top ring. could be wrong.
Both are marked with k-top on and the step ring has top written on the same side as the step. Could it be for catching combustion pressure and expanding to make a better seal? I don't see any purpose for that groove if it was an oil scraper.
 

·
Registered
Joined
·
1,913 Posts
under our lams system m600 is allowed to be unrestricted. m620 has greatly reduced throttle travel.

620 piston is too short for 600, it'll have very low comp. although it does have quite the crown, so dunno really. would be prone to pinging i'd think due to the excessive squish clearance.
 
1 - 14 of 14 Posts
Top