| Author | Message | ||
     Blake |
I think Captain Pete just has a thing for Pammy.  | ||
| Ccryder |
Thanks Captpete. Blake, whats wrong with having a thing for Pammy  Anyway, off to clean Stripe'r. Neil S. | ||
| Rocketman |
Neil I'd say by looking at those pic's that the rear cylinder was the cause of your problem. When I bought both my S1W's new they only lasted around two thousand miles before they blew up. The cause of both blow ups were due to rear cylinder overheating because the cylinder bores were in poor symetrical shape. Back in 1998 I can tell you for a fact that Buell was aware of this problem and their solution back then was to run with AAC's. Your pic's, all I've got to go on, look to show the rear cylinder failed first due to overheating and I'd say that has to be a mechanical problem and when it broke up, no doubt suddenly and with little warning, the debris took out the front cylinder also. In this type of scenario it's always the rear cylinder that fails first as it runs hottest. If I were you I'd be looking at the shape of those cylinders very carefully in an attempt to verify the above but it's important to establish what the 'real' shape of the cylinder WAS and NOT what the WEAR PATTERN might lead you to believe IS. From top to bottom they will be egg shaped and side to side they will be out of round. Without sounding like I'm trying to confuse you, you might find no noticeable wear shape at all and what you find may well be the original (poor) shape of those cylinders. Any good mechanic should be able to pin point the difference. Just remember that the ring swept area will determine the wear shape but the full length of the cylinder is your reference to its original shape which should have been perfectly parallel along their entire length (the Buell problem was they were NOT). I'd further say Neil that it's a testament to your care and devotion towards your Buell and Mobil 1 (and not forgetting how nice a geeza you are) that probably got you this far before it finally gave up. Good luck with the new motor and run with the Millenium's and forged pistons and your prayers will be answered. Rocket  | ||
| Pammy |
Sean, it wasn't a stock bore. | ||
| Rocketman |
Sorry I assumed it being a 96 S2T that it was running stock cylinders. Do we know what the bore is\was? Were Hurricane pistons maybe fitted to a stock bore? I assume otherwise if you say so Pammy darling, after all woman you are an expert ain't ya, unlike me  Rocket | ||
| Pammy |
I heard it was 1250...my expertise not required | ||
| 99x1 |
This cartoon reminded me of this thread - caption was "...time for a rebuild". Maybe it should be "oval cylinders?".  | ||
| Ccryder |
From what I was told, the cylinders were replaced with new stock cylinders less than a 1000 miles before I bought the bike. That was done when a head gasket blew. During that R&R it was noticed that the liner in one cylinder was loose. At the same time the heads went back to NRS for a check up. So this set up of Thunderstorm stage 1 heads, stock cylinders and Hurricane pistons with N4 cams had about 4000 miles before it went terminal. So I hope Sean is correct that the issue was roundness of the cylinder. The new set up is: Stage 1 heads, new valves, guides seals and springs. Millenium 1250 cylinders Hurricane pistons N4 cams Squirters 42 Mikuni SE lifters New oil pump S1 crank New ignition sensor. My last but least question is, I'm thinking about replacing the SE ignition module ($114) anybody have a suggestion on staying with the same model or going to a different module? Time4Sleep. Neil S | ||
| Peter |
Personally, I would get one where the advance curve can be changed. It'll make melting pistons easier too  | ||
| Rocketman |
Crane HI4E and Single Fire coil but I'm sure Aaron did some extensive comparisons way back which showed no performance advantages. If nothing else the Crane stuff will give you utter reliability, it's quality stuff obviously, and it's simple to install \ set up. Incidentally Neil, now you've pointed out they were stock cylinders I'm pretty certain that was the cause of failure. Sorry to sound so bold but I'm surprised no one said so earlier. I guess the professionals here wouldn't want to commit in case I'm (they could be) wrong. I'd be looking to confirm as much if that were my motor. Rocket | ||
| Aaron |
I really think he had some detonation going on, I'd be reluctant to blame the cylinders or the machine work. But I don't know, I didn't measure'em. I've had good luck with the HI-4E, the Dyna 2000, and the race kit module. They each have their pro's and con's, depends on the application. A '96 module has a good curve for a stockish motor, the only real reasons I can see for changing his module are to get a little higher rev limit and also the somewhat unlikely possibility that something with his module contributed to the failure. As mild as this motor is going to be, I'd be inclined to keep the costs down and go with a standard Dyna 2000 dual-fire and put it on curve 4 or just go with a race kit module. The important thing is to tune the bike up properly. | ||
| Josh_ |
Why not Stg2 heads? | ||
| Pammy |
Sean, that would be stock cylinders but NOT a stock bore....HELLO We have had zero trouble with stock cylinders. The problem with Neils motor was definitely overheating...what caused that is the crux of the failure. And the damage, being as extensive as it appears, will likely prohibit one from putting a finger directly on what initiated the problem. Kinda like the old, which came first, chicken or egg, quandry. | ||
| Blake |
I thought that Neil said they were new stock cylinders, did he say they were overbored? I agree with Pammy and Aaron. The Cylinders did not cause the problem. It had to be detonation. As to the integrity of the stock cylinders... I've seen/heard of unevenly worn stock cylinders or loose liners. After only 13K miles the cylinders on my Cyclone were worn terribly unevenly. They had four very prominent stripes where the honing marks were completely worn away, leaving instead a nice shiny mirror-like finish. The stripes corresponded to the parallel paths of the studs and oil pathway. Hmmmmm. | ||
| Rocketman |
Blake said 'I agree with Pammy and Aaron. The Cylinders did not cause the problem.It had to be detonation'. Pammy said We have had zero trouble with stock cylinders. Aaron said I'd be reluctant to blame the cylinders or the machine work. But I don't know, I didn't measure'em. What was ya saying Blake? The Cylinders did not cause the problem. Look I wish to lead no one down the garden path here nor do I wish to argue the point nor do I consider myself an expert specifically on Buell motors so I'll explain a little further then you can make up your own minds. It looked to me like the rear piston and cylinder overheated and the piston broke up. The front cylinder failure looks to be caused by the debris from the rear piston etc. Those pictures are not of a quality that makes the problem easy to asses , somewhat looking worse than in the flesh I suspect. At first glance it looks like overheating occured on the front of the rear piston. However the piston looks the same on the backside too yet the crown doesn't seem to be anywhere near as burnt as the thrust sides of the piston. If it was detonation that caused that scenario it's strange that it took out the thrust sides of the piston and not the crown. Make of it what you will. Incidentally the colouring on the front piston crown looks nice not that it matters now unless anyone wants to argue that too LOL. Rocket | ||
| Blake |
How would debris from the rear cylinder get into the front cylinder?  Consider... detonation with white-hot blowby on both cylinders, leading to loss of cylinder wall lubrication... Just a theory. I don't see how the cylinders would cause such a failure unless they were improperly sized. | ||
| Jprovo |
How would debris from the rear cylinder get into the front cylinder? Intake manifold? Rear cyl spits a piece of seat or valve into the manifold, and the front cyl sucks it up. I've seen it happen in A-series BMC mini engines, and they have a much more segregated intake system. James} | ||
| Blake |
The seats and valves were not damaged. Next answer? | ||
| Rocketman |
Are you serious Blake? And I thought you was the engineer? I mean why do you insist no matter what the thread in pulling peoples post apart? Really I \ we shouldn't have to quantify my \ our posts to satisfy your internet ego lust should we? Ever looked at the space that big round thing spins in? Ever heard of that fella who had an apple fall on his head a few years ago or even remember what he said? Your last sentence, kinda like a get outta Texas free thing, would be better if it ended or shaped. See the problem I have here Blake is I haven't really engaged in any technical questions for ages because this situation always happens where someone has to question the abilities of the person responding, in this instance me. So I tell you what, I don't like stepping on the toes of the real experts here like I used to in 1997 before I realised how good, no how great, the smart guys and one girl really are, and I don't like making a fool of myself either but I am somewhat of an expert myself not necessarily in things Buell \ HD but certainly with engines and no I don't have the certificates or math degree but I've seen enough engine internals to know the basic principals of how they work and funnily enough it's what I do for a living too. Where Neil's motor is concerned I passed comment because I thought the experts here had missed the point, maybe not. Sorry in future I'll keep it shut! Rocket returning to more interesting topics on Badweb like how to kill Iraqis. | ||
| Smadd |
Rocket! You're softening, man!! You wouldn't have given up so easily a couple of years ago!! Can't I do anything to help get you fired up? Hmmm... how 'bout this: Michael Schumacher.  Steve | ||
| Aaron |
I agree with Pammy, it's not going to be accurately diagnosed sitting here, and I'll add that speculation about it being a poor quality component from a supplier (in this case HD) perhaps isn't fair. | ||
| Jim_witt |
Sean ... you're getting to be a pussy in your old age. -JW:> | ||
| Jprovo |
The seats and valves were not damaged. Next answer? Seriously, Blake, you sound grumpy! I didn't see any pics of the head, so I don't know if they are damaged or not, I guess you have all the inside info I think that Rocket's case is more likely, the rear cyl failed, and debris from the piston breaking up got in-between the cyl and the skirt on the front cyl causing it to fail. Like Aaron, Pammy, and anyone else I missed said, you're not going to find the root cause of the problem by sitting in front of a computer and looking at four pictures of pistons. Hell, you might never find out the root cause. James | ||
| Blake |
So the rear cylinder can fail due to detonation, but the front cannot it requires debris from the rear? I agree, trying to diagnose the root cause of the failure here is not likely to yield conclusive results. Rocket, Lighten up. What's wrong, lost your brick? No one is attacking you or your status as a master mechanic. This is just mates talking shop. Poorly built mis-shaped cylinders would certainly be a bad thing. It is certainly a plausible cause for failure. Should be a fairly easy thing to confirm, no? | ||
| Jprovo |
You just like to debate! No, I didn't say that the front required debris from the rear to fail. I just said that I thought it was more likely that debris traveled trough the crankcase than the intake track. I was just trying to answer what I thought was a pretty basic question: How would debris from the rear cylinder get into the front cylinder? Heck, any number of things could have caused the engine to fail. It is obvious to the untrained eye (like the KIA driving estimator sitting next to me) that the rear piston is more swrewed up than the front. Does that mean that the font had a different failure mode than the rear? Does it really matter? Neil's engine is toast no matter how it failed. Back to the original topic, Ignition gone Bad? Well, having too much advance can lead to precombustion and overheating. Hell, I dunno, I just know that the ignition sensor looks toasted. Hey Neil, What day of the week was it when it happened? James | ||
| Aaron |
Several times I've pulled the top end off a motor that had cratered in one cylinder and found damage and debris in the other cylinder, as well as in the intake manifold. It's not unusual at all to get crossover damage. Once I found the entire head of a valve sitting squarely in the intake manifold directly behind the carburetor. | ||
| Blake |
Aaron, Was the valve head that you found behind the carburetor from a Kawasaki that you had passed at a high rate of speed. LOL! I can see debris getting out past a broken intake valve. I can see it getting between the cylinder wall and piston via crankcase. I don't see that as more probable than the front cylinder failing via the same mode as the rear but to a lesser extent. But I'm no expert. Maybe Neil will have the cylinders expertly measured and let us know the results. Me? Like to debate? Pshaw!  | ||
| Pammy |
The debris definitely is not contained to a specific area as a rule. Heat saturation was also a factor in the damage that I saw. A domino effect where one thing caused another, which caused another, so on and so forth is common in a catastrophe such as Neil's. Figuring out where it all began is the trick. We can usually make a somewhat pinpointed determination, but in this case where the damaged is so drastic and someone else took things apart (using some big tools), a specific diagnosis would be difficult. | ||
| Jprovo |
Pammy, I hear ya, It's kinda tough to measure a cylinder bore when someone just pressed a melted piston out of the bore with a hydraulic ram. (or beat it out with a 10-pound sledge) Of course, it doesn't help when half the piston and rings are permenantly stuck to the cylinder walls I use to love the guys who would walk in to my last job with a bunged-up two-stroke cylinder and head (cometimes the crank too). Often, the exhaust port would be filed with melted piston, and the rings imbedded in the head, and they would want to know what the cause was. I'd just have to shrug and say "Mix? Jetting? Coolant? Over-rev?... James | ||
| Pammy |
I can only imagine how much extra material there is on the walls of those cylinders. I went back and looked at the photo's(after someone said the cylinders had been replaced prior to this) again and noticed how new the pistons looked. How many miles were even on this motor? It was the intake sides that received the most damage...I guess it might be a bit difficult to discern considerable detonation over a loud Force exhaust. |
