If you look at my photo page, you will see an engine sitting in a box. That engine belongs to a friend of mine, and it is sitting in a box because his top ring shattered. We culdn't for the life of us figure out why this had happpened, he had always kept it mantained, and the events leading uto the discovery of this problem do not explain how this could have happened.

There is a forum member on here by the name of DuneRider650, whom I talk to quite often. If I remember correctly, he just had the same thing happen not too long ago. Kinda of funny I thought, but perhaps just a fluke.

Now this is what gets me. I have always taken good care of my machine, and the damn thing is almost brand new. I bought it just before christmas of 2003... rode it every now and then....and then parked it just before christmas of 2004 due to an accident. I have since then been doing everything to it, and it has not ran once since the day i parked it.

This morning I went to install an 11.5-1 comp piston, and just imagine what I found when I pulled my cylinder?? My top ring was shattered! It had ran, and from what I can remember, it ran pretty good up until now. The top ring is in probibly over 50 pieces, the ring groove is really worn in some spots, and there are a few small dings in my cylinder head. My friends cylinder head is beat to ****, and his piston has chunks missing around the edges. I'll bet mine wasn't too far off from ending up like his.

Now thats 3 people I personally know who have had this happen. It shows almost no symptoms until it's too late. How many others are there? How many are there going to be? Just think about it for a minute or two......I know I am

 

When I see or hear about shattered rings the first thing I think about is detonation or the ring end gap was too small, or both. I shattered rings on one of my turbo engines. It happened when I was running regular gas and 25PSI of boost. This happened for only about 3 or 4 seconds but it was REALLY knocking. In 3 seconds it shattered all of the top compression rings and pushed the head gasket.
Check for signs of detonation on the piston and plug. Is Bomb setting the ring gap too small? Maybe? Are you getting detonation and don't know about it? Maybe? Just my 2 cents.

 

All 3 of us are stock bore, stock stroke, and stock compression. My friend and I 95% of the time run premium, and the odd time if we are in a small town, we run 89 octane. Elevation for 2 of us I know for sure is about 2200 feet. I had the mods listed, and my friends was all stock. What are the signs of detonation? anything is possible....Oh and this I found as well. One of the bolts in the top of the head was loose...like 3 turns out loose. It's one of the 2 bolts on top holding the head to the cylinder. Thing is, that bolt has never been touched, not by me, not by my dealer, not by anyone. I can't see that being too big of a deal, considering the other 7 or so bolts/nuts...but like I said anything is possible. And why wasn't that bolt tight?

Thanks for your input.

 

I don't think that this is your cases, but I have built alot of drag/street engines for cars and I know that if the ring gap is a little tight and the engine gets a little over heated, then the rings can actually seize up in the cylinder for a split second and that sometimes causes them to break. I am not sure what bombs tolerances are but if they are on the tight side, "wich I know most are" then this could cause it. Detonation will deffinataly cause this, but usually this will show itself on the piston and the cylinder. In the cylinder it will actually look like it has more than one spot where the rings would stop when the piston is rising to the top. If you see this then it is detonation. The piston would actually look like it has pits in it and or a little wavy and you should see a little bit of aluminum on the plug and or the electrode bent or broke off, the spark plug check could be confusing if you see aluminum or bending of the electrode because running lean can cause that as well if you run it long enough, hope this info helps ya out. RUSS

 

I doubt it would be model wide - otherwise it would have come up a dozen times already on the forums. Are there any other similarities between the three machines in question? Gas used, mods, elevation, year /month of build date, vin number etc. Check the engine number as well. Perhaps all three had the jetting a little lean for the riding conditions etc?

I had a Suzuki LT250R seize up three times from being lean - always caused by that STUPID FMF exhaust I put on it. That fu#$% wouldn't seal and I tried soooooo many different ways. Finally that is when I got my 2001 DS and I've never had a 'major' problem since - or for that matter, no problems at all aside from what I caused on my own.

 

Everything looks good i guess to me, aside from the damage and resulting discolouration caused by the top ring being shattered. The plugs look OK, the cylinder wall is good, just could use a honing, and the piston just has a couple of dings from a piece of ring that somehow snuck through..

Now we did notice this.... If you take a piece of the ring, any random piece, and put it back into the ring groove, there is not one spot within the groove that comes close to fitting. Obviously there is a lot of wear in the grove on the one side, but the other side has little to no signs of wear, but the ring is still very sloppy in there.....

Could the wrong ring have ended up in there and it had enough play to eventually wear enough to bind???

I'll see if I can get some pics up.

 

well i got my modified endcap and thats the only mod...my plug colors are good and she isnt running to hot...there was no signs of the top ring broken, it always ran fine and i could pull 80mph for top speed, when my dealer put my engine together he mentioned that it was prob a put together error and bombardier did pay 3/4 the final price so they must of known something was wrong since my warrenty was over and they still paid. I ran 91 and 89 octane, there was never any pre dentonation noises from the engine and the mechanic never said anything about that being the case of it breaking the top ring.

 

Devin:

When I pulled my piston I found nothing wrong with either the piston, rings or the cylinder wall and mine is a 2004 as well. I think it may very well be just a coincidental fluke.

 

Are all these engines failures from 04' models??? This is definatley a new problem. Maybe Bombardier changed ring vendors in 04'??? or perhaps piston manufacturer's??? Like dunerider650 said , if BRP paid for most of his rebuild then they must be hearing this from their own engineers aswell. Cudo's to BRP for stepping up, and taking responibility and helping him out with cost of his rebiuld.





biggerisbetter.

 

Had another DS go in just a few weeks ago, 2004 model, they found a shattered ring that had worn through the piston, and ate up his cylinder walls, and mashed his head.....


my model number is 7995 manufactured on 08/2003