TRX250R.ORG
Workshop => Engine and Bottom End => Topic started by: rablack21 on February 21, 2014, 08:14:38 AM
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I tore me engine down last night to put new piston rings in, and this is what I found. The piston has a light seizure/scuffing on the left side between the exhaust port and boost port. No other places, just this one. I have no way of knowing when it actually happened, I'm guessing sometime last year.It appears to be a cold seizure, but strange that it is only in one place and this particular location. I have a race this Sunday so my question is: would you put it back together and run it anyway, or would you sit this race out and get a new piston and bore the cylinder?
Stakes:The is technically a season warmer race for us and doesn't count for our regular season. It is a large race to raise money for ST. Jude and you do get a few points for participation. The first race of the season starts in two weeks.
Cost: if I put it back together and race it, it will cost me a gasket set and the time to put it back together only to tear it apart again to put a new piston in it before the next race.
Worst case scenario: if I raced it "as is", and it seized on the track.
So, what would you guys do?
(http://forums.trx250r.org/vbulletin_imports/100_767_2017-04-18_8801.jpg)(http://forums.trx250r.org/vbulletin_imports/100_768_2017-04-18_4842.jpg)(http://forums.trx250r.org/vbulletin_imports/100_769_2017-04-18_679.jpg)(http://forums.trx250r.org/vbulletin_imports/100_770_2017-04-18_6929.jpg)(http://forums.trx250r.org/vbulletin_imports/100_771_2017-04-18_2827.jpg)(http://forums.trx250r.org/vbulletin_imports/100_772_2017-04-18_6306.jpg)(http://forums.trx250r.org/vbulletin_imports/100_773_2017-04-18_6119.jpg)
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I'd fix it while it's apart. Nothing worse than the engine locking up before a jump and causing you to get injured.
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I am as budget minded as anyone,, and I would polish the piston up with some 1200 grit and run it,,, maybe not a whole season ,, but to get by I see no reason not to,,
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top ends are so easy to pull off, i would just buff that piston up, put it back together, then go put a piston on order, and replace next week after you run this weekend to see if you have problems.
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I'd run it and stock it's replacement.
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That scuffing could very well be the piston slap I mentioned in your coolant thread. Do you have scuffing on the cylinder wall as well?
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That scuffing could very well be the piston slap I mentioned in your coolant thread. Do you have scuffing on the cylinder wall as well?
The cylinder wall is smooth. You can tell where the cross hatching has been "rubbed out" where that piston was moving up and down. But other than that the cylinder is completely smooth on the inside.
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put it together and ride it
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looks like whatever was there rode its way out the bottom
what are the last two pictures showing the ring gap?
why did you pull it apart in the first place?
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if you have the money fix it but i woulndnt let that scare me too much. if i wanted to ride.
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I have had pistons look much worse than that. Sanded, ran a hone through the cylinder and re-install.
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My bigger concern is that you're racing this weekend with a motor that you noted as overheating regularly. If you're going to get a new piston soon I'd try to get it honed or bored and throw a new piston in before the race.
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looks like whatever was there rode its way out the bottom
what are the last two pictures showing the ring gap?
why did you pull it apart in the first place?
To put new piston rings in.
I have had pistons look much worse than that. Sanded, ran a hone through the cylinder and re-install.
Thanks, this is starting to make me feel a little better about it.
It will be just for one race, but I didn't really want to get out there and it seize up on my either. Any idea on cause? I tend to agree with OJ, I think it was due to piston slap. If so, this is why I was installing new rings.
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Think about this.
If you have had over heating problems in the past, you know the hottest places in the cylinder bore will be around the exhaust. Since theres no bridge in the main exhaust port, the only part like a bridge, is the part of the sleeve between the main & aux exhaust ports.
With over heating, the higher heat will cause that small part of the bridge, in the exhaust area, to bulge out & take up piston to bore clearance & sometime result in piston seizure.
Note, that all these after market cylinders, Pro-x & ESR, tend to run hotter on the left front side & top of those cylinders & if you've noticed, most of the time when a inner o ring has blown, it will be in that left front corner that it happens on.
I would say sometime in the past, that area of the lite seizure must have got super hot for a real shot time & the small amount of damage was the result of it.
Now this might sound crazy from me & I'm a big boy if some of you want to laugh at me for this, but that small seize spot on the piston, the aluminum has melted & metal has been removed, so if you sand off that little spot, smooth out the ruffness, you know that part of the pistons not going to touch the bore any more.
Only things to think about afterwards, what was causing that one area in the cylinder to run hotter. Was it the fact, that side of the cylinder will run leaner than the right side & cause it to run hotter. Could it be an issue of port linking, on that side from the edge of the aux exhaust port window linking up with the machined area on the side of that old model piston.
Next thing, is all those up & down scars on the exhaust side of the piston ?. Could it be the pipes not sealed at every joint & raw air & maybe dust being sucked back in on the returning wave, or old burnt carbon inside the pipe flaking off & being pushed back in by the returning wave. Lot of scars on the exhaus side & hardly any on the intake side.
Every piece of an engine inside, when you look at it has a story to tell, like that black look to the piston between the top & second ring, its saying that top rings not sealing & letting burnt gas & oil blow by & collect on the piston in that area.
Even with all this going on, I would check the piston real close for cracks because of hours used & if none, smooth that spot out, put those new rings in & let it ride, but fatten up that main jet just a hair.
Neil
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I tore me engine down last night to put new piston rings in, and this is what I found. The piston has a light seizure/scuffing on the left side between the exhaust port and boost port. No other places, just this one. I have no way of knowing when it actually happened, I'm guessing sometime last year.It appears to be a cold seizure, but strange that it is only in one place and this particular location. I have a race this Sunday so my question is: would you put it back together and run it anyway, or would you sit this race out and get a new piston and bore the cylinder?
Stakes:The is technically a season warmer race for us and doesn't count for our regular season. It is a large race to raise money for ST. Jude and you do get a few points for participation. The first race of the season starts in two weeks.
Cost: if I put it back together and race it, it will cost me a gasket set and the time to put it back together only to tear it apart again to put a new piston in it before the next race.
Worst case scenario: if I raced it "as is", and it seized on the track.
So, what would you guys do?
(http://forums.trx250r.org/vbulletin_imports/100_767_2017-04-18_8020.jpg)(http://forums.trx250r.org/vbulletin_imports/100_768_2017-04-18_86.jpg)(http://forums.trx250r.org/vbulletin_imports/100_769_2017-04-18_8643.jpg)(http://forums.trx250r.org/vbulletin_imports/100_770_2017-04-18_7425.jpg)(http://forums.trx250r.org/vbulletin_imports/100_771_2017-04-18_6554.jpg)(http://forums.trx250r.org/vbulletin_imports/100_772_2017-04-18_1704.jpg)(http://forums.trx250r.org/vbulletin_imports/100_773_2017-04-18_3433.jpg)
The top of the piston shows that the piston crown temperature is normal to a little cool. The scuff (seized spot) is old. The piston has been run at least and hour or so since the seizure occurred. If it was a cold seizure or insufficient piston to cylinder wall clearance there will usually be a similar spot about 180 degrees from the spot you are showing.
Scuffs on the exhaust side of the piston skirt are common in the areas where the piston makes contact with the bridges between the exhaust ports. The areas around the exhaust port, especially the bridge areas run extremely hot. The hot areas really test the lubricants ability to do its job at extremely high temperatures. These hot areas also test the oil films THICKNESS to transfer heat from the hot surface to a cooler surface. The oil films thickness is primarily controlled by the temperature of the oil and premix oil ratio.
Look at the color of the big end of your connecting rod. I would not be surprised if the rod shows a slightly darker color in the area where the rod surrounds the crank pin. If this area is a little darker, this is a sign of insufficient lubrication and insufficient oil film thickness to transfer heat to the crank pin and crank webs. The bore and the rest of the piston skirt show some lubrications problems.
I would suggest that you take an oiled stone like you use to sharpen a knife and polish off the scuffed spot, put the engine back together, increase the amount of oil you put in the fuel and go racing.
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Love threads like this
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Think about this.
If you have had over heating problems in the past, you know the hottest places in the cylinder bore will be around the exhaust. Since theres no bridge in the main exhaust port, the only part like a bridge, is the part of the sleeve between the main & aux exhaust ports.
With over heating, the higher heat will cause that small part of the bridge, in the exhaust area, to bulge out & take up piston to bore clearance & sometime result in piston seizure.
Note, that all these after market cylinders, Pro-x & ESR, tend to run hotter on the left front side & top of those cylinders & if you've noticed, most of the time when a inner o ring has blown, it will be in that left front corner that it happens on.
I would say sometime in the past, that area of the lite seizure must have got super hot for a real shot time & the small amount of damage was the result of it.
Now this might sound crazy from me & I'm a big boy if some of you want to laugh at me for this, but that small seize spot on the piston, the aluminum has melted & metal has been removed, so if you sand off that little spot, smooth out the ruffness, you know that part of the pistons not going to touch the bore any more.
Only things to think about afterwards, what was causing that one area in the cylinder to run hotter. Was it the fact, that side of the cylinder will run leaner than the right side & cause it to run hotter. Could it be an issue of port linking, on that side from the edge of the aux exhaust port window linking up with the machined area on the side of that old model piston.
Next thing, is all those up & down scars on the exhaust side of the piston ?. Could it be the pipes not sealed at every joint & raw air & maybe dust being sucked back in on the returning wave, or old burnt carbon inside the pipe flaking off & being pushed back in by the returning wave. Lot of scars on the exhaus side & hardly any on the intake side.
Every piece of an engine inside, when you look at it has a story to tell, like that black look to the piston between the top & second ring, its saying that top rings not sealing & letting burnt gas & oil blow by & collect on the piston in that area.
Even with all this going on, I would check the piston real close for cracks because of hours used & if none, smooth that spot out, put those new rings in & let it ride, but fatten up that main jet just a hair.
Neil
I think you may be on to something. I did take notice that there was some grayish oily residue just on the outside of the pipe right there in front of the exhaust flange area. When I removed the pipe, I noticed that one of my orings on my double oring exhaust flange was broken and was not sealing well. This could very well have played into the issue.
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Can't beat those answers from Neil and Jerry. So how does he keep it from getting hot like that again? Also does he switch oil or just go from say 32:1 to 28:1?
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I hope none of us forget the people who come on here and help us,with out trying to sell us something.they make this forum a true pleasure to come on and learn
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I don't think there is one specific cause of this issue. I think several things have factored in. The fact that this engine got up to engine temps of 220-225° several times last year I'm sure didn't help. I don't really know how many hours I put on this engine during last years racing season. I should have kept up with it better. The fact that there is noticeable piston slap indicates the rings are wore out at the very least which could have very easily caused excessive heat in the piston and cylinder wall, well above what is supposed to be normal. I don't know how long the front of my pipe has not been sealed. I never noticed it not being sealed last year, but it would have started recently. Unfortunately, all of these conditions are abnormal to the engine's typical operation.
I am kicking myself my not pulling the head off of it during the off season to inspect everything after the end of the racing season. This would have made it easier to determine when it occurred. This could have occurred last year one of the times my engine was running extremely hot, and I never knew about it. This is an example of poor planning on my part.
Thanks to everyone for posting your thoughts. I will decide something by the time I get off of work.
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if you have the money fix it but i woulndnt let that scare me too much. if i wanted to ride.
maybe amsoil will pay for the repair ?
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jerry and neil,,, is it possible to put web cooling holes in the piston for the bridge between exhaust ports on these cylinders? or would it do any good? I have never had this issue but I am not real hard on stuff... just a thought,,,,,
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maybe amsoil will pay for the repair ?
This is not a lubricant quality related issue. Don't confuse that with a lack of lubrication issue. Almost all seizures are due to 1 of 3 causes, rapid expansion of the piston in a cold cylinder, the cylinder bore being too small for the size of the piston, and lack of lubrication. But there are many causes of lack of lubrication including overheating the engine, the engine running too lean causing too much heat, and an air leak which causes the engine to run lean leading to heat buildup, and lack of enough oil in the gas. There was no indication from my parts that there was a lack of proper lubrication due to lack of oil in the gas or that the film strength of the oil was not adequate under normal riding conditions. If there is a lean condition or an air leak or if the engine is overheating greatly for any reason, the piston and/or rings can expand or bulge to the point that it scrapes the oil right off of the cylinder wall creating metal to metal contact , and it doesn't matter at that point what oil or oil ratio you are running it will wipe it off as well. If this was an oil ratio related issue, then this would have continued to happen and should have completely seized by now. I have run the same ratio with the same engine for several years now, and ran the engine the same way. I find it hard to believe that it all of a sudden became a problem. There is just not enough evidence to support that. Plus, all the internal parts were coated with a film of oil when I tore the engine down, the crank rod showed zero discoloration, there was no discoloration in the wrist pin or on the underside of the piston, all indicating that oil migration was taking place in sufficient quantities.
There was, however, several indications that my engine had run lean, had an air leak, and exhaust leak, and overheated several times in the period of last year's racing season. All of the issues are associated with creating seizures. I cannot pinpoint which one was the cause or when it actually occurred. All I can do moving forward is to make sure I don't have any of these issues from this point forward.
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is it possible to put web cooling holes in the piston for the bridge between exhaust ports on these cylinders?
That's what I was just thinking, drilling a few little holes in the piston on each side of the main exhaust port to help lubricate the area between the main and sub exhaust ports. Like how pistons for a stock cylinder are drilled down the center front of the piston to help lubricate the bridge.
Like this one: (http://www.southbayriders.com/forums/attachments/417848/)
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At one time, Eddie had Wiseco put those lubricating holes in his pistons. They can't hurt, but if all parts are working correctly, not necessary.
(http://i532.photobucket.com/albums/ee328/RideRed187/250R%20Pics%20Parts/e2487fcf.jpg)
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i feel a better way to lubricate a specific area is with a angled/chamfered "hole" of sorts for example; using a spot drill instead of the small oiler holes as on the pic above and what is common by piston manufactures.
(http://forums.trx250r.org/vbulletin_imports/77_786_2017-04-18_7460.jpg)
(http://forums.trx250r.org/vbulletin_imports/77_787_2017-04-18_5653.jpg)
john
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That's what I was just thinking, drilling a few little holes in the piston on each side of the main exhaust port to help lubricate the area between the main and sub exhaust ports. Like how pistons for a stock cylinder are drilled down the center front of the piston to help lubricate the bridge.
Like this one: (http://www.southbayriders.com/forums/attachments/417848/)
i feel a better way to lubricate a specific area is with a angled/chamfered "hole" of sorts for example; using a spot drill instead of the small oiler holes as on the pic above and what is common by piston manufactures.
(http://forums.trx250r.org/vbulletin_imports/77_786_2017-04-18_8028.jpg)
(http://forums.trx250r.org/vbulletin_imports/77_787_2017-04-18_4365.jpg)
john
I like this idea ^^^.
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i feel a better way to lubricate a specific area is with a angled/chamfered "hole" of sorts for example; using a spot drill instead of the small oiler holes as on the pic above and what is common by piston manufactures.
(http://forums.trx250r.org/vbulletin_imports/77_786_2017-04-18_7688.jpg)
(http://forums.trx250r.org/vbulletin_imports/77_787_2017-04-18_5193.jpg)
john
This sounds like a good idea, chamfer the side of the hole that is against the cylinder so as to slow and diffuse the fresh oil mix as it passes through the piston from the crankcase and distribute it over a larger surface area than just a plain thru hole.
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Its hard to gauge if a motor is getting enough oil by looking at the amount of oil on a piston when dissembling a motor.
The way to know if it has enough oil is to put in its worst case scenario which is a long wide open run of say 500 feet
A two stroke will normally have a excess of oil in the crank case under normal driving conditions with allot of on and off throttle positions but the longer you hold it the more of this excess that gets cleaned out of the lower cases.
Woods bikes and MX bikes can probably get away with less oil but long runs and high heat do require more oil
Now I am not saying this was the cause but it may have helped, loose pistons do run hotter and high coolant temps only compound the problem.
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Has anyone tried the "Wet Oil Line Method" for jetting? The theory seems sound but it is more tedious and time consuming than the traditional plug chop.
http://www.702sportbikes.com/showthread.php?14147-Two-Stroke-Jetting-The-Wet-Oil-Line-Method
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At one time, Eddie had Wiseco put those lubricating holes in his pistons. They can't hurt, but if all parts are working correctly, not necessary.
(http://i532.photobucket.com/albums/ee328/RideRed187/250R%20Pics%20Parts/e2487fcf.jpg)
Drilling oil holes would not have prevented the seizure in the above picture
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Drilling oil holes would not have prevented the seizure in the above picture
you are right about that.haha something went wrong beyond a lubrication issue.
john
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Has anyone tried the "Wet Oil Line Method" for jetting? The theory seems sound but it is more tedious and time consuming than the traditional plug chop.
http://www.702sportbikes.com/showthread.php?14147-Two-Stroke-Jetting-The-Wet-Oil-Line-Method
Using the wet line method for jetting is like watching the height of the “mixture ring” from the intersection of the steel spark plug shell and the porcelain cone that surrounds the center electrode. Neither of these two methods can indicate when the engine is making maximum power nor guarantee you will not hurt the piston. These two methods rely on watching the operating temperature of a remote surface that can be easily changed without changing the combustion temperature. Only a stopwatch, a dyno, an acceleratometer, another vehicle of comparable performance can be used to measure or indicate when an engine is making maximum power.
The wet line method assumes that all two-stokes make the same exhaust temperature at WOT, ¾ throttle, ½ throttle and ¼ throttle. The wet line method assumes that the inside surface of the exhaust port operates at the same temperature whether the cylinder is liquid cooled, air-cooled with the exhaust port facing forward or air-cooled with the exhaust port facing to the rear. The wet line method assumes that all exhaust system designs operate at the same efficiency. The wet line method assumes that all two-strokes scavenge the same. The wet line method assumes all things are equal between all two strokes regardless of the manufacture.
A well-developed engine will start losing power most of the time when it is too lean without hurting the piston. An engine that has the wrong ignition timing, the wrong shape combustion chamber, a pipe that is not in complete harmony with the engine or using the wrong octane fuel, can make the engine go into detonation, then hurt a piston even when it is rich.
Make it easy on yourself and just tune the carburetor to where the engine runs well and monitor the spark plug and or piston crown for signs of detonation. If you engine has the piston to cylinder wall clearance set correctly for the coolant temp that you operate your engine, you will not usually hurt a piston until the engine starts experiencing detonation.
I have been tuning two-stroke engines for over 40 years and have not found any one method that is accurate by it’s self for determining the optimum jetting. We have to simultaneously use at least 3 of 5 senses that God gave us (Sight, hearing, feel, a stop watch or a dyno) to jet a two stroke optimally.
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IMO if drilling holes in your piston for better lubrication is the only thing that keeps your engine from seizing, then you have larger problems on your hands.
Honestly Ryan I still think you're not running enough of that Amsoil in your gas. I'm a big skeptic of that 50:1 or 100:1 ratio or whatever it is they recommend/guarantee.
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Honestly Ryan I still think you're not running enough of that Amsoil in your gas. I'm a big skeptic of that 50:1 or 100:1 ratio or whatever it is they recommend/guarantee.
I tend to agree with you. I've never would think of trying to run mix ratios like amsoil recommends
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IMO if drilling holes in your piston for better lubrication is the only thing that keeps your engine from seizing, then you have larger problems on your hands.
Honestly Ryan I still think you're not running enough of that Amsoil in your gas. I'm a big skeptic of that 50:1 or 100:1 ratio or whatever it is they recommend/guarantee.
I tend to agree with you. I've never would think of trying to run mix ratios like amsoil recommends
When you are comparing oil ratios, you have to make sure you are comparing apples to apples. Amsoil starts out at a higher viscosity than an oil that is recommended to be mixed 32:1. When they are both mixed with gas,at different ratios, they end up at the same viscosity when ready to use. At 50:1, Amsoil meets and exceeds the same oil lubricant requirements that every other oil on the market has to meet. The difference is you are getting a higher concentration of lubricating oil per bottle. Some oils have to cut their formulations (base stock plus additives) with chemicals to help make the formula more miscible and combust more cleanly. Because of this more, a lower oil ratio needs to be used to maintain the same level of protection.
On a side note, racers have been using higher ratios than 32:1 and 20:1 for years without complaints of their engines tearing up.I realize that 2 stroke quads may have not been using them for that long, mainly cause their not around as much anymore, but 2 stroke dirt bikes have been using higher oil ratios for a long time. It is not heresy to them, it is common practice. Not saying everyone does it, but alot of them. I sold out of all the Dominator I had at the race this weekend. I asked everyone of my customers, "what oil ratio do you run?" 50:1 was the response of all of them. Yes, even top level guys that run nationals. This is not to argue, just food for thought.
Aside from that, if I have an issue with the oil, I have peace of mind knowing that I can take it up with Amsoil. I don't know what happened with the customer in the story in the first part of this thread, but if there is a failure with the oil, they will cover it. Or if there is a recommendation that does not meet certain conditions, they want to know about it. They research and study these things very heavily. I spoke with them about this very issue a few days ago. They said that if the cause of failure cannot be determined by a failed part due to manufacturing defect, they will cover the cost even if the oil has been tested and resulted to still have it's lubricating properties. Yes, even in a 2 stroke, the residual oil in the engine can be analyzed. Basically, even if they can't find anything wrong with the engines parts or the oil, they will STILL cover the customer to keep their customers happy. I run Amsoil cause no other oil company other there offers this.
This thread has gotten really side tracked into alot of different ideas. To get back to the original thread subject, I sanded the piston down, put new rings in, and put the engine back together. I ran the engine at my race this weekend. I had no issues of overheating. As long as the quad is moving, it's happy. This indicates that my issue has been radiator capacity and air flow related due to the bigger bore and not actually an air leak or coolant system leak. This is good news. You guys talking about lubricating holes, you should start a new thread and discuss it. I think it would be interesting, but would be easier to search with it's own thread title.
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Look at the color of the big end of your connecting rod. I would not be surprised if the rod shows a slightly darker color in the area where the rod surrounds the crank pin. If this area is a little darker, this is a sign of insufficient lubrication and insufficient oil film thickness to transfer heat to the crank pin and crank webs. The bore and the rest of the piston skirt show some lubrication problems.
I would suggest that you take an oiled stone like you use to sharpen a knife and polish off the scuffed spot, put the engine back together, increase the amount of oil you put in the fuel and go racing.
When you are comparing oil ratios, you have to make sure you are comparing apples to apples. Amsoil starts out at a higher viscosity than an oil that is recommended to be mixed 32:1. When they are both mixed with gas,at different ratios, they end up at the same viscosity when ready to use. At 50:1, Amsoil meets and exceeds the same oil lubricant requirements that every other oil on the market has to meet. The difference is you are getting a higher concentration of lubricating oil per bottle. Some oils have to cut their formulations (base stock plus additives) with chemicals to help make the formula more miscible and combust more cleanly. Because of this more, a lower oil ratio needs to be used to maintain the same level of protection.
On a side note, racers have been using higher ratios than 32:1 and 20:1 for years without complaints of their engines tearing up.I realize that 2 stroke quads may have not been using them for that long, mainly cause their not around as much anymore, but 2 stroke dirt bikes have been using higher oil ratios for a long time. It is not heresy to them, it is common practice. Not saying everyone does it, but a lot of them. I sold out of all the Dominator I had at the race this weekend. I asked everyone of my customers, "what oil ratio do you run?" 50:1 was the response of all of them. Yes, even top level guys that run nationals. This is not to argue, just food for thought.
I understand the difference in viscosity when mixed. I just don't believe "Amsoil meets and exceeds the same oil lubricant requirements that every other oil on the market has to meet" claim.....says who? Amsoil themselves? Sounds like a good marketing scheme but I always question companies that make these bold claims. Kind of like "Simply the Best"..........
National racers using ratios higher than 32:1 are changing their top-ends much more frequently than your average Joe. I think if you expect any longevity out of a top-end then it's a good idea to run more oil than a national level racer.
Have you ever tried running 32:1?
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I understand the difference in viscosity when mixed. I just don't believe "Amsoil meets and exceeds the same oil lubricant requirements that every other oil on the market has to meet" claim.....says who? Amsoil themselves? Sounds like a good marketing scheme but I always question companies that make these bold claims. Kind of like "Simply the Best"..........
National racers using ratios higher than 32:1 are changing their top-ends much more frequently than your average Joe. I think if you expect any longevity out of a top-end then it's a good idea to run more oil than a national level racer.
Have you ever tried running 32:1?
If they did not meet the regulation standards, they would not be able to sell the oil. That's basic for most all lubricants sold in any market. You say you don't believe they meet and/or exceed same oil requirements. Have you ever seen any data that showed that they do not? What makes it a scheme, because they sell through dealer and not massive chain stores? Hate to tell ya, but alot of good companies do this.
Yes, I agree. national racers do tear their stuff down more often. There was just a reference. Most of my customers this weekend are the guys that are paying for their own stuff trying to take care of their race equipment as best as possible. These are the ones that like the longevity and protection they get from Amsoil.
Yes, I have ran 32:1 before. Not really sure why that matters.
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If they did not meet the regulation standards, they would not be able to sell the oil. That's basic for most all lubricants sold in any market. You say you don't believe they meet and/or exceed same oil requirements. Have you ever seen any data that showed that they do not? What makes it a scheme, because they sell through dealer and not massive chain stores? Hate to tell ya, but alot of good companies do this.
Yes, I agree. national racers do tear their stuff down more often. There was just a reference. Most of my customers this weekend are the guys that are paying for their own stuff trying to take care of their race equipment as best as possible. These are the ones that like the longevity and protection they get from Amsoil.
Yes, I have ran 32:1 before. Not really sure why that matters.
I was just curious if you have run 32:1 over the lifetime of a top-end as opposed to 50:1. Being that all other variables are the same, I wonder what the effects would be.
I understand all oil sold must meet regulatory requirements. And no I haven't seen any data that proves Amsoil wrong, but then again I haven't seen any data that substantiates their claims. I would definitely be open to reading that though. Like I said I want to believe that the claims are true, I just always question companies that make bold claims. I take everything with a grain of salt.
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ive always thought 32:1 to be insufficient. got no personal evidence to support it but thats my thought. too much oil never killed a engine so i mix it real heavy. probly the only thing in gordon jennings book i put much value in was his oil test. you cant convince me to use less oil. stop trying to persaude him to use more oil :congratulatory:
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.........................Yes, I have ran 32:1 before. Not really sure why that matters...................
If you stay with two strokes long enough at the high ratios and have engines that produce a lot of power at high RPM, you will eventually find what other have found with oil ratios that you have been innocently coerced into running.
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Ski-doo in attempt to run leaner oil ratios has special sealed crank bearings with ultra expensive grease and they have probably the highest crank issues in the industry
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We rebuild 5 to 10 two stroke crankshafts and bore 10 to 20 cylinders a week and have done so for over 30 years. I always ask what type of air filter, air filter oil they are using, what type of premix oil they have been using and at what ratio. We also ask how much time there is on the crank or cylinder bore. Using this data we see patterns and trends that have guided us in our recommendations to customers that ask questions on how they can prevent recurring failures on crank shafts, pistons and cylinder wall damage.
After rebuilding over 10,000 crankshafts the number one cause of premature connecting rod bearing failure is dirt getting past the air filter. The number two reason for premature crank failure is high premix ratios. The third most common reason for premature crank failure is the brand of oil. High milage is seldom a common factor cause of crank failure.
Summarizing the data we have gathered on the ranking order of connecting rod bearing and main bearing failures are:
1. Dirt getting into the engine.
2. High premix oil ratios
3. Brand of premix oil
4. Milage on the part.
After over boring 20,000 cylinders we have also observed trends as to why the piston failed or the reason the cylinder needed boring.
1. Dirt getting into the engine.
2. Burned pistons as a result of improper jetting, fuel starvation or fuel whose octane rating was too low.
3. High premix oil ratios.
4. Operating the engine in a manner that is not matched with the design intent or purpose of the engine
5. Brand of premix oil.
6. Milage.
Our observed trends for reasons for engine failure seem to match up with the recommendations that can be found in the first few pages in the owners manuals for any of these vehicles.
Keep the air filter clean and oiled properly, use fresh fuel of the proper octane rating at a mixture of 20:1 that meets the manufacture's lubrication requirements and operate the vehicle in a manner for which it was designed.
I do not remember ever seeing a two stroke oil of any brand that would not meet the engine manufacturer's lubrication requirements. I have seen a trend in engine failures for customers using oils and where the oil manufacture says "You do not have to use as much of our oil because our lubricating properties are superior to other oils on the market".
The majority of the oils that our industry uses are packaged by the major oil refiners. The remainder of the aftermarket oil companies buy their oil and additives from the major oil refiners and blend and package their product or wave their magic wand over the pipe as oil it is flowing from the refiners tank into their private label package.
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i think its a wasted effort to try and convince someone to use a specific amount or type of oil. people will do what they want to do regardless what evidence is put in their face. the best example is wiseco cranks. theyre a time bomb but people still buy em even after seeing pictures of when they fly apart