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'79 Special completely detonated at 85mph yesterday
- Thread starter phaedrus
- Start date
meanEG
XS650 Enthusiast
clean it up, valve job, done.
Even the side that didn't blow looks like it was running hot. See all those white "chip" marks around the spark plug hole? That looks like a sign of pre-detonation or "pinging". The other side shows signs of it as well, although not as easily seen now after the meltdown. Pamco with E-advance or basic Pamco still using the ATU? Did you check timing at full advance to insure it wasn't too advanced?
Still had the mechanical advance on there, which just so happens to have been removed, cleaned, and reinstalled about 100 miles ago. The thing was running better than ever. Much less vibey on the freeway. My buddy kept forgetting to bring the timing light by though so it hadn't been re-checked....
Ummmm- can't tell if kidding or serious. Assume kidding!
madjap
XS650 Addict
Duuuuuude...! YOU know how to PARRRRR-TAYYYYY! Sorry for your meltdown man. Not everyone has the present economic stability to overcome all ticks and tocks, and I understand what you were 'trying' to get to. When it comes down to diapers, rent or toys, the toys often take the back seat. BUT, you admittedly pushed the envelope to the edge of the table with an 85mph run, then maybe flicked that envelope a little... you looked around quickly. Maybe slyly...? Thought, 'one more time'. Tapped that envelope a little and suddenly there was a ZZZZCCCHHHHRRRRRR and the envelope turned on you. It pooped on your hand, stunk up your den and made your finger a little stained and stinky. You'll be fine, you know the path to recovery. Again, sorry it went ka-blooey! That sucks! You seem to have a good attitude over it tho. Maybe drinking grain alcohol or some sort of addiction would help you be more bitter or bitchy? HA!
Bloody mess. Personally i wouldn't use a thing off that motor again, about as useful as tits on a bull. Every, and i mean every thing will be damaged. The cases might be the only thing worth something but think of all that beaten and molten metal clogging up the oil passages, gonna get all that out? The fly wheels may be salvageable, worth keeping if you build a 270 crank. Asking questions about the condition of areas and their fix-ability, Valve seats), is mute until you strip it down completely, don't like your chances when the pic shows a large peace of the ring has gone through there.
What amazes me is............... why didn't it throw a rod through the case, as 5twins stated this was an ignition problem and not a little end. Timing, lean carbs or bad advance.
Some times spending money, is a case of saving money, and this is surly a case in point. Think of the cost it would have been compared to the cost now.
What amazes me is............... why didn't it throw a rod through the case, as 5twins stated this was an ignition problem and not a little end. Timing, lean carbs or bad advance.
Some times spending money, is a case of saving money, and this is surly a case in point. Think of the cost it would have been compared to the cost now.
Yeah the cop definitely came and broke up my party this time. I don't really have any room for more grain alcohol in my normal operations, but I'll see if I can squeeze a snifter in just for you. Things are already looking like a buttah-side-up scenario though. Annoyingly to some, neglecting this engine till it failed might be just the catalyst needed to get me a shiny new rebuilt motor for almost $0.... Stay tuned
650Skull- things are shaping up to where I have a new donor engine possibility that needs exactly the parts that might still be OK from this engine! So far I would need the cam, the head oiler pipes, the bottom sump cover, and my Mikuni carbs and charging system. That'd be moving up to an '83 mill from my '79. Considering a 270 rephase along the way since it would be a full rebuild process anyway. I already have a full gasket and seals kit and engine bolt set sitting on my bench. Hopefully all trading for service in my IT specialty.
In the interest of autopsy, the specific failure cause seems to be an oil leak developed in my top end. I've battled bottom end leaks for some time and finally got the drips of my garage floor by following the external clutch rod seal replacement process and new single rod upgrade. I also did the (amazing) chisel-strike-on-6-sides leak fix to the neutral wire fitting.
I had noticed my carbs were oily on the outside after my runs, including my toolkit that was mounted behind them. Nothing pooled or dripped when parked, though, so I was missing the feedback on oil loss I was used to. (Yes I understand there is a dipstick, and he goes on the saddle.) The thing always burned oil and smoked at take off out one pipe so sloppy black oil was expected. I had put a topper of Rotella in there a few days before and it seemed quite happy. 'Quite Happy' is a technical term and mine was within spec.
In the end, I always knew the XS's legendary durability would be its demise at my hands. Like the girlfriend who says everything is 'fine' till the day she dumps you, so too was my engine.
I had noticed my carbs were oily on the outside after my runs, including my toolkit that was mounted behind them. Nothing pooled or dripped when parked, though, so I was missing the feedback on oil loss I was used to. (Yes I understand there is a dipstick, and he goes on the saddle.) The thing always burned oil and smoked at take off out one pipe so sloppy black oil was expected. I had put a topper of Rotella in there a few days before and it seemed quite happy. 'Quite Happy' is a technical term and mine was within spec.
In the end, I always knew the XS's legendary durability would be its demise at my hands. Like the girlfriend who says everything is 'fine' till the day she dumps you, so too was my engine.
Whether the engine destruction was due to oil leakage or oil loss or timing advance set wrong or carbs set too lean, etc. is really
moot at this time. All you've proven is that you can take a rugged, bullet proof engine and destroy it. If you had taken the engine apart when you bought it, and repaired its worn internal parts (also checked timing and carbs were adjusted correctly), you would still be driving the bike to-day.
moot at this time. All you've proven is that you can take a rugged, bullet proof engine and destroy it. If you had taken the engine apart when you bought it, and repaired its worn internal parts (also checked timing and carbs were adjusted correctly), you would still be driving the bike to-day.
Yeah, it's super weird, right? There weren't at super villians, cosmic rays, or sabotage elves like you see in most other mechanical failures. You are wise to point that out, again. Do you want to send flowers to stand by its body, or donate to a worthy charity in the bike's name? You've become close to the machine lo these couple'a days.
BWHAHAHAHA I think what he really wants is to hop his happy ass on his scooter and come fix it for you.
Quote, " the specific failure cause seems to be an oil leak developed in my top end"
Wow....................you're a real dreamer. So, now your story is, "the engine must have developed an oil leak, and that's why the engine blew up, its not my fault. So what if the engine had a loud knock for over a year, I thought that was normal"
Wow....................you're a real dreamer. So, now your story is, "the engine must have developed an oil leak, and that's why the engine blew up, its not my fault. So what if the engine had a loud knock for over a year, I thought that was normal"
If you treat your girlfriends like your bike...................for them to hang around long enough, to actually call them a girlfriend, to get dumped is a given.
Well it is easy to diagnose the oil spray on the carbs, (looking at the pic of the bike), and it wasn't an oil leak causing that.
Look the whole thing is funny i get that and your a comedian to boot.
What i also see is someone who isn't going to listen because he already knows.
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double post crap
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Quote;
" Like the girlfriend who says everything is 'fine' till the day she dumps you, so too was my engine. "
You just don't have a clue. Sad to tell you but your engine was not saying everything is "fine". For a year it was saying, "help me, my internal parts are hurting real bad". When you didn't take notice, the engine said "I'm out of here" and dumped you out on the freeway
" Like the girlfriend who says everything is 'fine' till the day she dumps you, so too was my engine. "
You just don't have a clue. Sad to tell you but your engine was not saying everything is "fine". For a year it was saying, "help me, my internal parts are hurting real bad". When you didn't take notice, the engine said "I'm out of here" and dumped you out on the freeway
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7. If a thread turns into a bitch fight or name calling and character bashing, it will be deleted or edited (cleaned up). This site is not the place for grade-school drama.
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7. If a thread turns into a bitch fight or name calling and character bashing, it will be deleted or edited (cleaned up). This site is not the place for grade-school drama.
Yes, but some guys literally ask for it, lol. There may have been nothing wrong with any of the engine components. The knock could have been timing related. If your timing is off a little, too far advanced a little, you can get pinging. If it's off a lot you can actually get a knock. That could have been the case here, and he rode it that way for like a year. Short hops and local riding wasn't enough to lunch the motor, but that 85 M.P.H. blast down the interstate certainly was.
I'm afraid that if you "tune" your new motor with the diligence and care you applied to the old one, you're going to end up with a second pile of scrap metal before too long, lol.
I'm afraid that if you "tune" your new motor with the diligence and care you applied to the old one, you're going to end up with a second pile of scrap metal before too long, lol.
