Touring at 100 kph in 6th - Can it destroy your engine?
#41
06-24-2012, 06:49 PM
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My gas while in Canada may have been `low test` without the Octane booster the one dealer recommended vs using just premium (due to ethanol content in the latter), but wasn`t really `low test` once the octane was boosted right? Perhaps poor quality fuel with 15% ethanol, but not low test. Plus most of my detonation occurred in the US where I was using premium.
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#42
06-24-2012, 07:20 PM
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I`m torn between it being the sole culprit, and as Hopper implied, combined with lugging over-stressing/over-heating the piston dome (it ultimately fractured over by the exh valves.....he said it was like a chipmunk when at it), conn rods and ultimately the crank pin where the big end of the conn rod mounts. The latter process would only make detonation worse. Or, it was the sole cause of the detonation and it had nothing to do with octane at all. I understand that an engine can detonate if it`s a) too lean and b) too hot, though sufficient octane will resist it. I may have had enough to resist detonation in a 2500+ rpm operating engine, but not while lugging. One difference about Yellowstone is elevation, as well there is some climbing, and maybe I was climbing in 6th even if I did keep it above 2000 rpm.
#43
06-24-2012, 07:34 PM
Awesome indeed, thanks a lot for the detail and time/thought that took to help. I`ll try to get some pictures. The crankshaft and cylinder is in a box at our summer home, while the mechanic kept the piston as a show piece but I can get a picture. So maybe my mechanic is right that I should run at 5th gear and only use 6th for 120 kph+, because it resulted in top end (made worse by detonation) and crank pin damage evidenced by the blued conn rod big ends......though someone else said twin cam conn rods are heat treated so come blued. I`ll ask him if the crank was also out of true, and mention to him about new crank conn rods being blue. There are different amounts of `blue` so maybe he knows they`re slightly blue but this was abnormal. I`ll try to post a picture here so you can see/compare to what a new one should look like. I was going to listen to him regardless, given the risk and he`s the one who studied the parts directly, but it`s nice to have some confirmation to his theory I couldn`t get out of Harley.
As for his technique of rebuilding and then starting to hear for debris wasn`t his plan....it just happened that way. He tore it down to find the bad piston/cylinder, and seeing the fracture of the piston, flushed oil through the cases several times and thought he got it all. He did this to save me money, since as he said, going into the bottom end is a big job. When re-assembled he heard a tiny metallic `ting` sound once in awhile so he said NOW he has to go down into the bottom end.
As for the primary case damage possibly being from his not stripping down to the cases to clean, how could a bit of metal crack the primary case? I just can`t envision it. After all the flushing they did, and the tiny metallic sound he described that was barely audible, I didn`t think that could crack a case and wreck that bearing when that`s a separately sealed unit from where the metal-containing-oil was circulating.
My gas while in Canada may have been `low test` without the Octane booster the one dealer recommended vs using just premium (due to ethanol content in the latter), but wasn`t really `low test` once the octane was boosted right? Perhaps poor quality fuel with 15% ethanol, but not low test. Plus most of my detonation occurred in the US where I was using premium.
All that said - then why in the world would Harley themselves say in their manual and in denials to any problem, that we should run 6th gear at 100 or even 90 kph even on a flat stretch? Their top technicians and engineers should know this, if they`re designing the things in the first place, in particular if they have to pay for damage done by running the bikes according to said manual during the warranty period. If anyone should be an expert at engine operation it should be `The Harley Davidson Motor Company`. It`s not like this is a new engine/transmission.....didn`t the 6 speed come out in 2007? The fact they lowered the ratios in 09 and newer to speed up the engine at legal speeds should attest to the fact they`re aware of a problem, unless it was just a ridability and not reliability/durability reason behind it.
As for his technique of rebuilding and then starting to hear for debris wasn`t his plan....it just happened that way. He tore it down to find the bad piston/cylinder, and seeing the fracture of the piston, flushed oil through the cases several times and thought he got it all. He did this to save me money, since as he said, going into the bottom end is a big job. When re-assembled he heard a tiny metallic `ting` sound once in awhile so he said NOW he has to go down into the bottom end.
As for the primary case damage possibly being from his not stripping down to the cases to clean, how could a bit of metal crack the primary case? I just can`t envision it. After all the flushing they did, and the tiny metallic sound he described that was barely audible, I didn`t think that could crack a case and wreck that bearing when that`s a separately sealed unit from where the metal-containing-oil was circulating.
My gas while in Canada may have been `low test` without the Octane booster the one dealer recommended vs using just premium (due to ethanol content in the latter), but wasn`t really `low test` once the octane was boosted right? Perhaps poor quality fuel with 15% ethanol, but not low test. Plus most of my detonation occurred in the US where I was using premium.
All that said - then why in the world would Harley themselves say in their manual and in denials to any problem, that we should run 6th gear at 100 or even 90 kph even on a flat stretch? Their top technicians and engineers should know this, if they`re designing the things in the first place, in particular if they have to pay for damage done by running the bikes according to said manual during the warranty period. If anyone should be an expert at engine operation it should be `The Harley Davidson Motor Company`. It`s not like this is a new engine/transmission.....didn`t the 6 speed come out in 2007? The fact they lowered the ratios in 09 and newer to speed up the engine at legal speeds should attest to the fact they`re aware of a problem, unless it was just a ridability and not reliability/durability reason behind it.
Well, I would listen to the mechanic who advised against lugging. He is the guy who sees the insides of these engines and knows what is going on. The dealer who told you it is ok, he is probably a salesman, not a tech, and is probably parroting official Harley line without really knowing what the situation is.
And Harley is known to kind of cover up on known issues. Like the Twinkie cranks running out of true. All of a sudden the official allowable factory tolerance for crank runout jumped from .001" to .010". Problem solved. No more warranty claims.
Not sure what you are saying about the primary bearing. Which bearing exactly is it? If it is the crank sprocket shaft bearing, it runs in the engine oil and one tiny piece of piston/ring debris going through can trash it. As can other debris clogging the oil pump intake.
I would just ride on and use fifth gear more often.
#44
06-24-2012, 08:31 PM
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Well, I would listen to the mechanic who advised against lugging. He is the guy who sees the insides of these engines and knows what is going on. The dealer who told you it is ok, he is probably a salesman, not a tech, and is probably parroting official Harley line without really knowing what the situation is.
And Harley is known to kind of cover up on known issues. Like the Twinkie cranks running out of true. All of a sudden the official allowable factory tolerance for crank runout jumped from .001" to .010". Problem solved. No more warranty claims.
Not sure what you are saying about the primary bearing. Which bearing exactly is it? If it is the crank sprocket shaft bearing, it runs in the engine oil and one tiny piece of piston/ring debris going through can trash it. As can other debris clogging the oil pump intake.
I would just ride on and use fifth gear more often.
And Harley is known to kind of cover up on known issues. Like the Twinkie cranks running out of true. All of a sudden the official allowable factory tolerance for crank runout jumped from .001" to .010". Problem solved. No more warranty claims.
Not sure what you are saying about the primary bearing. Which bearing exactly is it? If it is the crank sprocket shaft bearing, it runs in the engine oil and one tiny piece of piston/ring debris going through can trash it. As can other debris clogging the oil pump intake.
I would just ride on and use fifth gear more often.
It was the dealer`s service manager which I would think means he used to be a mechanic (and was good enough to get that position eventually). Anyway yes he could well be towing the company line. But he wasn`t just a salesman or manager of some other department.
I`ll find out what bearing it is - my understanding was that it was a bearing within that primary drive case. Plus the case itself cracked and required welding/painting. The bearing cost about $40 as I recall....not that knowing the price will help much.
#45
06-24-2012, 08:45 PM
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#46
06-25-2012, 05:35 AM
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#47
06-25-2012, 05:54 AM
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They were also only $49/hour so at worst it worked out to the same as most shops.
#48
06-25-2012, 08:51 AM
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#49
06-25-2012, 10:49 AM
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Yes that was low class - oh, and I posted those not because I'm planning to buy one. I found it during my search for Harley crank issues, and thought I'd get feedback here on what's true (and worth doing something to prevent more issues after already replacing my motor once when it was a relatively new bike) and what's an exaggeration, minor or outright wrong.
#50
06-26-2012, 07:43 AM
lugging
First of all let me say I have some experience in the real world. 40 years non-stop riding and have owned and maintained all of them myself, Harleys for the last 10 years. My friends and I are all die hard Iron butt riders and all of us have done 1000 mile days. I have probably over 200,000 under my now old ***, probably much more, can't remember all the mileages on all the ricers I've owned. One of my friends, an engineer for an auto company, excitedly told me about tests they were doing on synthetic oils. Seems GM was having select people evaluate extended oil interval on Cadillacs (and later Corvettes) and than testing the oil. Mobil One could go 25,000 with minimal breakdown with routine filter changes. That person still has my second Gold Wing with over 300,000 on it. It never broke down, ever and is still maintaining excellent cylinder pressure. I never looked back, all my bikes used nothing but Mobil One since than. Over the last 30 years I've listened to all the horror stories that pistons and cranks will explode through cases etc and the common thread is they have all had problems and I have NEVER EVER had to fix anything internal but tires and brakes even though I literally ride 2 to 3 times more than them. "Mechanics" seem to be the most opinionated although I've never heard them agree on anything! So who's the better teacher? A 27 year old who who is still trying to express himself through tattoos and skin head haircuts as evidence of their machismo despite a total absence of military experience or the millions of satisfied users of synthetics with out any breakdowns whatsoever. Your choice..."dude." I also agree it's silly to lug a motor and I don't do it on my 08.