| Author |
Message |
    
Rocketman
| | Posted on Thursday, June 26, 2003 - 07:42 pm: | 
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So Peter what is the conclusion? Looks like the ole hot spot scenario is favourite. What did the plug look like?
I bought a XS650 years ago, running (just) on one lung. Two dodgy looking scoucers had ridden her over from Liverpool to visit a friend in Hull prison. They'd ridden her hard all the way until she gave up the ghost. I gave £110 for her, very cheap, after poking a welding rod down one plug hole. Suffice to say the rod went a long way. I had the piston crown welded some days later, sat with a file for an hour or so, re-ringed her and she ran like a good un for thousands of miles after that. Hey it was 19 years ago though and I did give her an oil and filter change, generous basket that I was back then. Apart from the piston having a hole in her the plug had melted. No carb \ inlet problem. No timing \ ignition problem just a plug gone bad.
Rocket  |
Pammy
| | Posted on Thursday, June 26, 2003 - 07:55 pm: |
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Sean that piston was obviously broken, not melted. What's wrong with ya...got lip gloss in yer eyes? |
Peter
| | Posted on Friday, June 27, 2003 - 03:12 am: |
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I'm quite sure it was detonation. I heard it on the second and last laps of my time on the track, so it had already been getting caned for about 20 minutes until then. Actually on the left hander after that bit of kitty litter Rocket <grin>.
Maybe a bit too much advance or too steep a slope, 11:1 comp, warm day and running it up to 7500 through most gear changes, French fuel..... who knows? Combination of all?
It definitely looks broken, not melted, but the plug and exhaust valve both had alumin(i)um on them. |
Hans
| | Posted on Friday, June 27, 2003 - 08:10 am: |
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"I'm quite sure it was detonation."
Indeed: Your piston looks like this one:
 |
Ccryder
| | Posted on Friday, June 27, 2003 - 12:20 pm: |
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Is my photography that bad or what??? I post picts of these fine looking cylinders (since they were part of a heated discussion) and no one even makes a comment about how bad a photographer I am  .
Anyway, the top end parts are headed to Al, NRS did a great turn around on the heads and parts ( thanks Justin, Susan and Brian). So by the 8th of July, when I get back from FL on Stripe'r, I'll travel to IL and reover Passion's heart.
To all on this site, I really do appreciate everyone's input and concern. This is the collective I've come to know and love.  .
Time2Work.
Neil S. |
Rick_a
| | Posted on Friday, June 27, 2003 - 02:57 pm: |
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How does a spark plug go "bad" and ruin a motor? Doesn't seem probable. The only engine failures I know of caused by plugs are due to wrong heat range, type, or are brought on by other engine failures like detonation, pre-ignition, or foreign objects.
This guy last week...hands me a plug that looks like the end was literally blown up...tells me he needs cooler range plugs because his nitrous was burning them up... |
Rocketman
| | Posted on Friday, June 27, 2003 - 04:32 pm: |
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Pammy I'd say that piston broke because of the excessive heat. If it hadn't have broken it would have melted had the motor continued to run or not been shut down. That's what I meant.
Anyway what's with this role reversal stuff? Guys wrench, yeah wrench baby, and the chics wear the lip gloss. Last time I was wearing lip gloss it was down below so to speak, but I didn't put it there. Now if you knows about that......um........ I don't remember, but you lot plied me with a shit load of Long Island ice tea's in Wendover and I'm not sure who I ended up sleeping with.
Rocket |
Funjimmy
| | Posted on Friday, June 27, 2003 - 05:21 pm: |
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Speaking of spark plug heat ranges and all. Perhaps you could help me figure this all out. I have Branch dual plug heads with J&E domed pistons in my S1. The bike runs great but the oil temp in the aluminum oil tank won't get hotter than approx 180 degrees. And that is running hard and fast on a warm (70-75 deg) day.
Question. When running dual plugs, should the heat range of those plugs be hotter, cooler or the same, as using single plug heads? I'm leaning toward a hotter plug, as NGK states that the plug conducts heat from the combustion chamber, out to the cooling system, and with two plugs conduction heat out, it seems that a hotter plug would be the logical choice.
Am I on the right track here? Your help is appreciated.
Thanks
FunJimmy |
Blake
| | Posted on Friday, June 27, 2003 - 06:11 pm: |
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Jimmy,
No, if the bike runs well and the plugs are not fouling, do not change them. Your oil is fine and well withing the expected range of temperature, especially for an aluminum oil tank. You might also check the accuracy of your temperature gage. |
Rocketman
| | Posted on Friday, June 27, 2003 - 08:16 pm: |
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A plugs heat range is a measure of the plugs ability to withstand thermal loads. What's best for your motor I don't know but I'd suggest to start with the usual plug(s) and see what they look like during and after a normal running cycle and listen / feel for misfire detonation or similar and change accordingly. Trial and error.
Rocket |
Pammy
| | Posted on Saturday, June 28, 2003 - 06:56 am: |
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"Last time I was wearing lip gloss it was down below so to speak, but I didn't put it there. Now if you knows about that......um........"
I thought the proper 'ointment', in that instance was KY jelly...what you Brits won't try wouldn't fill a post-it. And I am sorry, I don't know much about it. Except'n I heard on the news yesterday, that they lifted the ban on 'same sex' unions in the States here, so you might wanna move...
And those of us who were sober that night, last saw you with manley sort of woman, so I wouldn't try to re-live that moment if I were you. That is a definite case of what you don't remember, can't come back to haunt you. Does the Johnny Cash ditty "A Boy Named Sue" mean anything to you?
Sean, you know I love ya man...you are just a man-whore and can't help yourself...
There was a hot spot in the center of the piston, but was far from the 'black death' associated with melt down. Peter said he had run it 20 minutes after he heard the first sign of detonation. It may have been a contributing factor, but it wasn't THE reason.
I'll be sitting here with my big wrench awaiting your response. |
Cjmblast
| | Posted on Saturday, June 28, 2003 - 07:51 am: |
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This thread is beginning to contain
TOO MUCH INFORMATION !! |
Funjimmy
| | Posted on Saturday, June 28, 2003 - 11:51 am: |
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This is the statement I recently found on the NGK web page.
SPARK PLUG BASICS:
The spark plug has two primary functions:
To ignite the air/fuel mixture
To remove heat from the combustion chamber
...The temperature of the spark plug's firing end must be kept low enough to prevent pre-ignition, but high enough to prevent fouling. This is called "Thermal Performance", and is determined by the heat range selected.
It is important to remember that spark plugs do not create heat, they can only remove heat. The spark plug works as a heat exchanger by pulling unwanted thermal energy away from the combustion chamber, and transferring the heat to the engine's cooling system. The heat range is defined as a plug's ability to dissipate heat.
The rate of heat transfer is determined by:
The insulator nose length
Gas volume around the insulator nose
The materials/construction of the center electrode and porcelain insulator.
A spark plug's heat range has no relationship to the actual voltage transferred though the spark plug. Rather, the heat range is a measure of the spark plug's ability to remove heat from the combustion chamber. The heat range measurement is determined by several factors; the length of the ceramic center insulator nose and its' ability to absorb and transfer combustion heat, the material composition of the insulator and center electrode material.
Interesting!
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Ccryder
| | Posted on Thursday, July 17, 2003 - 08:19 am: |
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Some updates on Passion:
Her new engine is running strong and smooth. I set the timing last night and ran her 35 miles for a nice bug splattered break-in (Note to self: Wear a helmet and jacket so you at least don't feel the critters crawling after they slam into you.).
Just so no one thinks I've flipped, I rode without a helmet to get an ear full of my engine over my exhaust (This is rare for me!). The only thing remaining is to R&R the exhaust to fix an exhaust leak tonight. Time for more miles and smiles tonight.
Later
Neil S. |
Torqd
| | Posted on Thursday, July 17, 2003 - 10:28 am: |
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Keep us posted Neil :-) |
Ccryder
| | Posted on Tuesday, July 22, 2003 - 09:28 am: |
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Well this should be last for now. I put a new stator in last night (old one was grounded) and Passion seems to be running stronger every mile. By the end of the week I'll have the 500 mile break in finished and be ready for a dyno tune.
Thanks again for all the help and concern.
Time2Work
Neil S. |
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