Tired Combat Wombat
Re: Tired Combat Wombat
One last thing I can't tell from the photos is the chamfering of the ports, especially the exhaust port. The exhaust port looks quite wide. Is it possible the ring was snagging a bit and causing blow-by? It really looks like the failure is limited to a couple areas where combustion was getting past the ring. Once the oil was cooked off below the ring in one place, it wouldn't have taken long to cause the displacement of material shown in the photos and the general degree of failure. Displaced metal trapped the ring, probably in one spot, probably where the damage is greatest. Once the ring was unable to track the cylinder wall even in one spot, the rest of the failure would be a given. Detonation would be a contributor to such a failure.
Re: Tired Combat Wombat
DG, you bring up an interesting point on detonation. I always like to think backwards in the timeline of a catastrophic event. In my position I say the engine got hot because of too small of a jet to provide cooling and lubrication for the conditions combined and the new tolerances of a rebuilt engine. When the engine overheated the oil broke down and was unable to lubricate the cylinder, piston and ring. Detonation probably did occur around the edge of the piston because of the glowing ring. Finally the piston melted and the ring was coated with molten aluminum and retreated into its groove and compression was lost. Detonation was just the result of a series of events caused by the engine getting too hot. Good observation on your part DG. I might also note that in my opinion over 90% of seizures in 2-stroke engines are caused by a too lean situation. This one has all of the precursers of this type of event. What else could it be? We seem to be getting further and further off course on the simplest solution it could be. Again this is my opinion but I have seen this event dozens if not hundreds of times in my racing career.
Maxie
Maxie
Re: Tired Combat Wombat
Ok, I have a little time now and after reading your comments I am ready to offer up my thoughts. I have the advantage of being able to examine the piston and sometimes pictures are not quite the same. I did take the photos in a manner to disclose what I noted.
1. Ring end gap is on the opposite side of the piston and all is well there.
2. The ceramic coating on the piston and combustion chamber, only in the squish band area, is gone. What looks like a burn pattern in the initial pictures is actually reflecting the missing coating. The ceramic coating on the rest of the combustion chamber and piston crown is in excellent condition. The surface where the coating is missing is kind of rough. Some roughness under the coating is expected as it is part of the prep process for the coating. Texture is rougher than expected though.
3. There was an oil film remaining on the piston, pin and bearing.
4. Under side of piston crown is a nice tan color.
5. Piston ring is stuck due to displaced metal and engine operation ceased.
Taking into account the spark plug, combustion chamber and piston, looks like detonation to me also. Many times detonation is so severe and the resulting damage so great it is difficult to tell what happened. In this case the piston ring stuck and prevented further engine operation allowing a cause to be determined. I would expect detonation to begin in the area of the squish band and that would explain the excellent condition of the remaining ceramic coating.....detonation exceeded the ability of the coating in the squish band area of the piston and combustion chamber. If you can say there are degrees of detonation, it looks like we were just a little past the point of safe operation and maximum performance. The under side of the piston crown is very telling and does not show evidence of excess heat beyond the ability of the piston material. Lack of heat damage on top of the piston crown is telling also......although if detonation evidence did not exist I would chalk it up to excess heat in the exhaust port area due to lean mixture.
What to do.
1. A richer fuel mixture should reduced combustion temperature and may prevent failure.
2. Retarding ignition timing should also reduce combustion temperature and may prevent failure.
3. Using a higher octane fuel which better resistance to detonation.
4. Reduce compression.
In this case richening the fuel mixture and / or retarding the timing may prevent detonation but would reduce performance. Both timing and fuel mixture appear to be in the desired operating ranges. Also, richening the mixture in this case may lead to an over rich condition and plug fouling. When racing, operating at top performance with out failure is desired. Considering the evidence we were not far off that mark. Seems to me the best thing to do is reduce compression or use a better grade of fuel.
At this point the cylinder is at Power Seal to true the bore and Nicasil coating. Going back to the same .040 bore we had when this engine was built. When initially assemble I used a copper .010 head gasket. I have the option of using the standard .020 head gasket....depends on cranking compression readings. I do not remember what the cranking compression was before failure. I also have a single petal reed to install instead of the two piece. If time allows I also have a 30mm round slide new production carb to test.
With out having the piston available the prior speculation was just that......needed the other piece of the puzzle. I hope no ones feeling were hurt and we can disagree. Like Max, I try to inject some humor and hope that was understood.
Danny
1. Ring end gap is on the opposite side of the piston and all is well there.
2. The ceramic coating on the piston and combustion chamber, only in the squish band area, is gone. What looks like a burn pattern in the initial pictures is actually reflecting the missing coating. The ceramic coating on the rest of the combustion chamber and piston crown is in excellent condition. The surface where the coating is missing is kind of rough. Some roughness under the coating is expected as it is part of the prep process for the coating. Texture is rougher than expected though.
3. There was an oil film remaining on the piston, pin and bearing.
4. Under side of piston crown is a nice tan color.
5. Piston ring is stuck due to displaced metal and engine operation ceased.
Taking into account the spark plug, combustion chamber and piston, looks like detonation to me also. Many times detonation is so severe and the resulting damage so great it is difficult to tell what happened. In this case the piston ring stuck and prevented further engine operation allowing a cause to be determined. I would expect detonation to begin in the area of the squish band and that would explain the excellent condition of the remaining ceramic coating.....detonation exceeded the ability of the coating in the squish band area of the piston and combustion chamber. If you can say there are degrees of detonation, it looks like we were just a little past the point of safe operation and maximum performance. The under side of the piston crown is very telling and does not show evidence of excess heat beyond the ability of the piston material. Lack of heat damage on top of the piston crown is telling also......although if detonation evidence did not exist I would chalk it up to excess heat in the exhaust port area due to lean mixture.
What to do.
1. A richer fuel mixture should reduced combustion temperature and may prevent failure.
2. Retarding ignition timing should also reduce combustion temperature and may prevent failure.
3. Using a higher octane fuel which better resistance to detonation.
4. Reduce compression.
In this case richening the fuel mixture and / or retarding the timing may prevent detonation but would reduce performance. Both timing and fuel mixture appear to be in the desired operating ranges. Also, richening the mixture in this case may lead to an over rich condition and plug fouling. When racing, operating at top performance with out failure is desired. Considering the evidence we were not far off that mark. Seems to me the best thing to do is reduce compression or use a better grade of fuel.
At this point the cylinder is at Power Seal to true the bore and Nicasil coating. Going back to the same .040 bore we had when this engine was built. When initially assemble I used a copper .010 head gasket. I have the option of using the standard .020 head gasket....depends on cranking compression readings. I do not remember what the cranking compression was before failure. I also have a single petal reed to install instead of the two piece. If time allows I also have a 30mm round slide new production carb to test.
With out having the piston available the prior speculation was just that......needed the other piece of the puzzle. I hope no ones feeling were hurt and we can disagree. Like Max, I try to inject some humor and hope that was understood.
Danny
Last edited by dcooke007 on Sun May 10, 2015 5:29 pm, edited 1 time in total.
Re: Tired Combat Wombat
GMC,
The exhaust port is stock dimension and properly chamfered.
I did speak to Will and he was using a mix of pump and race fuel. He also stated he thought it may be more pump than race in this particular mix. Once the engine is reassembled cranking compression will be carefully measured.
Danny
The exhaust port is stock dimension and properly chamfered.
I did speak to Will and he was using a mix of pump and race fuel. He also stated he thought it may be more pump than race in this particular mix. Once the engine is reassembled cranking compression will be carefully measured.
Danny
Re: Tired Combat Wombat
Danny,
In order of priority, I would go from #4 to #1 in sequential order, i.e., reduce compression, raise octane, etc. the copper head gasket is a good idea if you can find one stock thickness. Or, thicker base gasket. Sometimes easier to do, and just as effective. The tiny shift in port timing won't change anything. The nicasil is a good idea. Couldn't see the chamfering in the photos, it was just a thought.
I notice that Klemm offers a head detune for 91 octane. Sounds intriguing. I may contact them for more info. Seems counterintuitive to detune a bike but probably cheaper than race gas. Has anyone tried 100LL av gas? I don't know if it can be purchased for non-aviation use, but as I recall it is roughly like old time 97 octane fuel.
And I would suggest a larger countershaft sprocket to stretch out fifth gear. From the video it sounded like he was running fourth and fifth mostly, where I would rather be running third and fourth, with fifth only on long straights. Might help the bike stay in the zone and not have to scream as much. In the vid, it didn't sound so extreme so he must have done the high revving after the video ran out.
I am curious, what was the problem on the starting line? Cold start? Looked like he had to open the start circuit to get it going.
In order of priority, I would go from #4 to #1 in sequential order, i.e., reduce compression, raise octane, etc. the copper head gasket is a good idea if you can find one stock thickness. Or, thicker base gasket. Sometimes easier to do, and just as effective. The tiny shift in port timing won't change anything. The nicasil is a good idea. Couldn't see the chamfering in the photos, it was just a thought.
I notice that Klemm offers a head detune for 91 octane. Sounds intriguing. I may contact them for more info. Seems counterintuitive to detune a bike but probably cheaper than race gas. Has anyone tried 100LL av gas? I don't know if it can be purchased for non-aviation use, but as I recall it is roughly like old time 97 octane fuel.
And I would suggest a larger countershaft sprocket to stretch out fifth gear. From the video it sounded like he was running fourth and fifth mostly, where I would rather be running third and fourth, with fifth only on long straights. Might help the bike stay in the zone and not have to scream as much. In the vid, it didn't sound so extreme so he must have done the high revving after the video ran out.
I am curious, what was the problem on the starting line? Cold start? Looked like he had to open the start circuit to get it going.
Re: Tired Combat Wombat
Compression / fuel is the first area of correction. Will did not want a loss of performance so racing gas is ok if we have to go that route. A lot will depend on what is discovered with cranking compression. Based on the evidence I think the thicker head gasket would have taken care of most of the detonation concern along with a little better fuel. We want as much engine performance as possible with out going over the edge. I do not think we were that far over the line. The .010 thinner head gasket is supposed to be good for approximately 10 psi extra cranking compression.
Will was running a 62 rear sprocket and a 58 tooth was ordered along with the engine parts.
The starting line problem was simply a matter of Will not warming the engine up enough. The bike has been so easy to start he got complaisant.
As long as Power Seal doesn't take to long to return the cylinder and piston we will be retuning this bike with additional mods for better performance....one piece reed petals and 2mm larger spigot mount carb. At this point I am comfortable that the root cause of failure has been determine and I am comfortable proceeding with these mods. If the root cause had not been determined I would not proceed with any other changes until further testing had been performed.
Danny
Will was running a 62 rear sprocket and a 58 tooth was ordered along with the engine parts.
The starting line problem was simply a matter of Will not warming the engine up enough. The bike has been so easy to start he got complaisant.
As long as Power Seal doesn't take to long to return the cylinder and piston we will be retuning this bike with additional mods for better performance....one piece reed petals and 2mm larger spigot mount carb. At this point I am comfortable that the root cause of failure has been determine and I am comfortable proceeding with these mods. If the root cause had not been determined I would not proceed with any other changes until further testing had been performed.
Danny
Re: Tired Combat Wombat
Almost forgot, I have been discussing cylinder head torque grooves with Rich. My understanding is torque grooves also helps to resist detonation. Also material removed would lower compression....although it may be a negligible amount.
Danny
Danny
Re: Tired Combat Wombat
Danny, It sounds like you are on top of it as usual. I seriously doubt that your engine needed any more than a richer mix. We all should remember that for all practical purposes ALL of the engines lubricant (at full throttle) is coming through the main jet and most of cooling is coming through the carb (except in the case of a liquid cooled engine). We MUST keep the engine cooler than the temperature at which lubricants fail and things such as detonation start to happen. The thinner head gasket concerns me somewhat but it was probably only a small part of all the many factors that caused the overheating of the engine. I would go back with the standard one or at least test the compression on both. As for the fuel, all of us are burning the same stuff with no problems. I would not recommend Aviation fuel for the reason that it appears to burn too slow. Tests with that fuel actually caused overheating in two engines that we tested. We never did figure out why but we suspected a longer burn time rather than a quick pop. Even premium fuels of the time had some of these slow burn qualities. We burned regular pump gas in all our race engines of the day as I do on my modified 94A engine today. Break-in as we all know is the most critical time in an engines life. More is better. This was probably one of the main factors in the failure of this engine but there were many. After break-in it's always a good idea to look at the piston one more time. I think detonation was probably not an issue until after the engine began to fail. I think you would have heard it happening before it failed.
I don't claim to be a expert on 2-stroke technology but this is based on experiences that we had in my long racing career. I hope this helps!
Maxie
I don't claim to be a expert on 2-stroke technology but this is based on experiences that we had in my long racing career. I hope this helps!
Maxie
Re: Tired Combat Wombat
I did the torque grooves on my 97 head. Very easy to do. I can see them mitigating detonation because they channel flame spread out to the edges of the squish evenly around the circle. The amount of metal removed is not great, so the drop in compression is not great either. I didn't notice a thing in the line of a drop of performance. Can't say yet whether I saw an increase in preformance, either, but still working out the carburetion. Currently running a 28 instead of the 32, and have way more midrange and torque, a little less scream on top, but runs very clean, so the grooves don't hurt a thing. Haven't had the head off since to check internal condition, still breaking it in. Plugs are very clean. Rich has good things to say about them, as do others into hotrods. I think it is an easy mod, with all good things and no downside that I see. It might give you an edge without decreasing performance, which your customer will appreciate.
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Modracer70
- Posts: 33
- Joined: Sat Aug 03, 2013 1:50 am
Re: Tired Combat Wombat
On the Klemmvintage web site there is an article about detonation, and a link to a discussion about gasoline, including AV gas. I've been running 93 octane non ethanol, with a 25 % AV gas in my Super Combat street bike 165 lbs cranking pressure, with torque grooves in head, also in my 03 KTM 200 2 stroke dual purpose bike with great results. Both bikes are not run at wide open throttle for an extended amount of time, using Redline racing oil at 50:1.
Just my 2 cents.
Dave
Just my 2 cents.
Dave
Re: Tired Combat Wombat
Revisiting the AV gas subject, my comments above were from a long time ago. The two engines tested were fueled with straight AV gas at 20:1 oil mix. During a hard run the engines would just stop running and seem to be over heated. After a cooling period they could be restarted and seemed normal. We didn't pursue it any further and moved on. We suspected a too slow burn but it could have been vapor lock. This got us to thinking about octane and went to regular gas in all our engines even today. They actually seemed to perform better. I think race fuels of today would probably be the way to go if you are going the high compression route.
This is just my experiences with AV gas in the distant past but and I'm sure all has changed but I thought you might like to hear about our old research.
Later--Maxie
This is just my experiences with AV gas in the distant past but and I'm sure all has changed but I thought you might like to hear about our old research.
Later--Maxie
Re: Tired Combat Wombat
Hey Danny, may I steal a couple of pictures of your piston for an article on piston seizure for the Resonator? Being a photographer I'm always spooked about using other people's work without their permission.
Maxie
Maxie
Re: Tired Combat Wombat
Hey Max,
No problem. Photography is one of my hobbies also. Just happy not to have to buy and process all that film these days. Although I do miss my Nikon 35mm and 2.8 35-70 lens.
Danny
No problem. Photography is one of my hobbies also. Just happy not to have to buy and process all that film these days. Although I do miss my Nikon 35mm and 2.8 35-70 lens.
Danny
Re: Tired Combat Wombat
Thanks Danny, You do know your 35-70mm f2.8 will fit on a new digital Nikon body! 
Maxie
Maxie
Re: Tired Combat Wombat
Yes, I just went with a more portable Nikon digital. My old 35mm stuff has been sold some time ago. Had a Nikon 8008s body and the lens was Nikon 35-70 and the aperture was as small as 2.8 through out the focal range. Lens also had macro. Paid a lot for that lens. At that time I was inspecting and documenting automotive parts failure and had to have the pictures to get paid. That set up never let me down. Always got my pictures.hodakamax wrote:Thanks Danny, You do know your 35-70mm f2.8 will fit on a new digital Nikon body!
Maxie
Danny
Re: Tired Combat Wombat
THe av gas mentioned here is actually much less prone to vapor lock cuz its designed to run at high altitude where auto gas would have severe vapor lock problems and the only problem down here actually is not a big issue , it just begins the burn at a slower rate which can slow down engine response a bit
Rich
Rich
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Bullfrog
- Posts: 2772
- Joined: Mon Jul 22, 2013 4:05 pm
- Location: Oregon, 12 miles from the center of the Hodaka Universe(Athena)
Re: Tired Combat Wombat
Danny:
I would highly recommend checking the compression. The only reference I saw in this thread about compression prior to seizure was "I don't remember what the compression was . . ." There was a mention of using a thin head gasket (red flag?).
Within the past couple of years I had a situation where I spent a couple of days trying to jet a competition bike and could NOT get rid of detonation. I finally checked compression (which I had assumed was correct because expert tuners had provided the components for the engine) and found 200+psi compression!! No amount of carb tuning was going to get rid of detonation in that situation!! NOTE: Engine ran like a scalded Cheetah . . . but would not have lasted through a moto . . . Found out later the head was configured for a Super Combat, but was mounted on a Combat cylinder.
Steps were taken to correct compression . . . and THEN the carb tuning did what it was supposed to do. Ran the bike HARD for two days after that in competition. Sweet engine!!
Get your compression down to 150psi (maybe 160/165 . . . IF using racing fuel, excellent oil, jetting is correct AND -- REPEAT . . . AND rider is sensitive enough to detect detonation and adjust throttle accordingly). Did I mention that the rider MUST be sensitive to (and recognize) detonation if you are going to use compression higher than 150?
Ed
PS: Sorry I didn't read this thread thoroughly after the concerns about chain alignment.
I would highly recommend checking the compression. The only reference I saw in this thread about compression prior to seizure was "I don't remember what the compression was . . ." There was a mention of using a thin head gasket (red flag?).
Within the past couple of years I had a situation where I spent a couple of days trying to jet a competition bike and could NOT get rid of detonation. I finally checked compression (which I had assumed was correct because expert tuners had provided the components for the engine) and found 200+psi compression!! No amount of carb tuning was going to get rid of detonation in that situation!! NOTE: Engine ran like a scalded Cheetah . . . but would not have lasted through a moto . . . Found out later the head was configured for a Super Combat, but was mounted on a Combat cylinder.
Steps were taken to correct compression . . . and THEN the carb tuning did what it was supposed to do. Ran the bike HARD for two days after that in competition. Sweet engine!!
Get your compression down to 150psi (maybe 160/165 . . . IF using racing fuel, excellent oil, jetting is correct AND -- REPEAT . . . AND rider is sensitive enough to detect detonation and adjust throttle accordingly). Did I mention that the rider MUST be sensitive to (and recognize) detonation if you are going to use compression higher than 150?
Ed
PS: Sorry I didn't read this thread thoroughly after the concerns about chain alignment.
Keep the rubber side down!
Re: Tired Combat Wombat
Ed is right on track with his post. Detonation never seemed to be a problem in all of my racing of Hodaka engines. It was because I never used anything other the factory combinations and a stock gasket. Our engines were run on regular gas with no problems. More compression almost always makes more power but with an increase in heat (also a decrease in reliability). I'm mentioning this of course to remind us that jetting is a factor when things run hotter.
Ed is also right in that you can feel detonation. Even though I never felt detonation in a Hodaka engine, I also raced a 4-stroke air cooled single that would detonate under extreme racing conditions. It's time to roll the throttle back when you feel and hear detonation happening. A richer main jet helped but did not cure the situation. It just had too much compression "for the conditions".
I was somewhat concerned when I read about the thinner head gasket but it sounds like Danny's list of things to do is right on track!
As always,
Max
Ed is also right in that you can feel detonation. Even though I never felt detonation in a Hodaka engine, I also raced a 4-stroke air cooled single that would detonate under extreme racing conditions. It's time to roll the throttle back when you feel and hear detonation happening. A richer main jet helped but did not cure the situation. It just had too much compression "for the conditions".
I was somewhat concerned when I read about the thinner head gasket but it sounds like Danny's list of things to do is right on track!
As always,
Max
Re: Tired Combat Wombat
Hey Ed,
Cranking compression check is at the top of the list. I will report what I find when the engine is re-assembled. Waiting for all the parts to arrive at the moment.
Even though the pictures of the piston damage look bad the damage is not as severe as it seems. The degree of damage to me would indicate we were just past the point of safe operation for the conditions. The engine jetting was initially adjusted when the air temp was in the 70's. The day of this race the air temps were in the 40's and that may have been enough difference to push it over the edge of safe operation. I would like to attend all the races with Will but that is not possible. So I will just have to school him a bit.
Been waiting for your input and always appreciated. You missed some of the good stuff.
Danny
Cranking compression check is at the top of the list. I will report what I find when the engine is re-assembled. Waiting for all the parts to arrive at the moment.
Even though the pictures of the piston damage look bad the damage is not as severe as it seems. The degree of damage to me would indicate we were just past the point of safe operation for the conditions. The engine jetting was initially adjusted when the air temp was in the 70's. The day of this race the air temps were in the 40's and that may have been enough difference to push it over the edge of safe operation. I would like to attend all the races with Will but that is not possible. So I will just have to school him a bit.
Been waiting for your input and always appreciated. You missed some of the good stuff.
Danny
Re: Tired Combat Wombat
JUst a another think to look at is that increasing compression isnt always the ultimate goal , But! also to restore compression lost from increasing port timing , the highter the ports the lower the compression gets. In a four stroke same principle goes when a wilder cam is used with more duration and overlap, compression needs to be restored . Raising compression on a stock engine needs to be monitered closley with the possibiliy of retarding ignition timing also . This can be a long new subject so I will stop now.
Rich
Rich
Re: Tired Combat Wombat
It's been amazing watching and reading what you're doing with this bike. I don't feel so all alone with my '76 Wombat! I hope I get mine running again soon. Waiting for the key which should be here tomorrow. Keep up the great work! ; D Victor
1978 175SL
1976 03 Wombat
1975 99 Road Toad (2)
1973 96 Dirt Squirt (2)
1973 “Wombat Combat”
1973 Combat Wombat
1972 94 Wombat (2)
1972 Super Squirt
1971 92B+ Ace
1970 92B Ace 100B (2)
1968 92 Ace 100
1966 Ace 90
; D Victor
Re: Tired Combat Wombat
Thanks Vic. We will get your bike going too.
Danny
Danny
Re: Tired Combat Wombat
Ok, today I have definitely discovered the root cause of failure. The evidence was staring me in the face but I just did not see it. I will begin by asking some questions.
1. Why did the spark plug appear normal with this type failure?
2. Why was the scuffing on the piston exhaust skirt off set to the left of the exhaust port rather than more centered?
3. Why no evidence of excess heat on the underside of the piston crown?
4. Why was the ceramic coating missing on the intake area of piston crown and combustion chamber. Seems it should have been etched away in the hottest part which should be the exhaust side?
I wanted to remove the piston ring and see what it might tell me. Using a 5 power loupe I noticed this. The edge of the piston crown is hitting the edge of the combustion chamber on the intake side opposite the scoring on the exhaust side of the piston. The impact area is very small about .010 to .015 inch across the top of the crown and about .003 to .005 deep. I would suspect the piston and head did not make contact at modest rpms. However as engine speed increased and the rod stretched contact occurred. Metal displaced from the piston crown and cylinder head contact forced the opposite side of the piston hard against the cylinder wall exceeding the ability of the oil film to prevent metal to metal contact. From that point it was all down hill from there. I could draw a lot more conclusions but I think that will do for now. Correcting this condition is first priority.
Danny
1. Why did the spark plug appear normal with this type failure?
2. Why was the scuffing on the piston exhaust skirt off set to the left of the exhaust port rather than more centered?
3. Why no evidence of excess heat on the underside of the piston crown?
4. Why was the ceramic coating missing on the intake area of piston crown and combustion chamber. Seems it should have been etched away in the hottest part which should be the exhaust side?
I wanted to remove the piston ring and see what it might tell me. Using a 5 power loupe I noticed this. The edge of the piston crown is hitting the edge of the combustion chamber on the intake side opposite the scoring on the exhaust side of the piston. The impact area is very small about .010 to .015 inch across the top of the crown and about .003 to .005 deep. I would suspect the piston and head did not make contact at modest rpms. However as engine speed increased and the rod stretched contact occurred. Metal displaced from the piston crown and cylinder head contact forced the opposite side of the piston hard against the cylinder wall exceeding the ability of the oil film to prevent metal to metal contact. From that point it was all down hill from there. I could draw a lot more conclusions but I think that will do for now. Correcting this condition is first priority.
Danny
Re: Tired Combat Wombat
WOW! Appears non of our ideas were accurate. Anyway it was a good discussion and we can all add another reason for seizures to our list.
Danny's sharp eye came through again.
Danny's sharp eye came through again.
Bill Chapman, Monument, CO
Raced and Modified Hodakas in Statesville NC back in the day.
Raced and Modified Hodakas in Statesville NC back in the day.
Re: Tired Combat Wombat
Like I said, 90% of all piston seizures are caused by being too lean. Maybe this falls in the 10% bracket. We did not have this information in the beginning and I always go with the odds. Look at it this way, there's only a 10% chance we're wrong! More evidence, Different odds. I don't think anyone was wrong on this discussion and I'm sure everybody including me learned something or they weren't listening. Good discussion!
Maxie
PS--There's still a good chance that this damage didn't cause the seizure but this certainly could start the process. Let's not jump to conclusions. A good detective would notice that the seizure didn't seem too start at that point. Like I said before, Air disasters are always caused by more than one event. That event could be adding more heat, we need to remember that as Bill said, "for the conditions", The story is probably not over. Odds are changing, I give it 50-50.
More evidence, Different odds. I don't think anyone was wrong on this discussion and I'm sure everybody including me learned something or they weren't listening. Good discussion!Maxie
PS--There's still a good chance that this damage didn't cause the seizure but this certainly could start the process. Let's not jump to conclusions. A good detective would notice that the seizure didn't seem too start at that point. Like I said before, Air disasters are always caused by more than one event. That event could be adding more heat, we need to remember that as Bill said, "for the conditions", The story is probably not over. Odds are changing, I give it 50-50.
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