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Discussion Starter #1
I have a 2002 Road King Classic, almost 2000 miles on the Big Bore Stage 2 installation, that, once it is warmed up, it REALLY pings from about 2200 to 3000 rpm. This is especially bad when it's under load, like going up a hill. I know this is very damaging to the engine. I always have used 91 or 92 octane premium fuel. Any hints or info would be greatly appreciated!!
 

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Discussion Starter #2
Since I posted this (rookie today!) I have searched and found many items regarding this very problem. Mine goes in for the 2500 mi. check (LOL) soon, will bring it up of course. Is it OK to use 104+ or other octane boosters to help the detonation/pinging? Thanks.
 

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Hard to give an opinion without the exact description of all the parts used on the bike. If there is no obvious mismatch, while it certainly can be a ignition issue, on this type of bike one would look at the fuel curve first.
 

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Discussion Starter #4
Hippo, all parts are the factory 95" parts, 203 cams, pistons, cylinders and recalibration of the ECM. Done at the dealership I bought the bike at new this last March. The more I read, the more this appears like a pattern of sorts with these bikes (?) Thanks.
 

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How about an oil cooler to fix your problem?

While researching Oil Coolers, have read where many people with upgrade kits noticed that their pinging disapered with the oil cooler kits.

Will be interesting if your pinging goes away this winter, if you don't figure it out by then...
 

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Discussion Starter #6
I wondered about the oil cooler, I've read some dubious reports that they aren't all they're cracked up to be, but that's certainly not from personal experience. The pinging only occurs once the bike heats up, which sounds normal by the responses I've gotten. I'm willing to try about anything, certainly don't want to punch a piston! Thanks.
 

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Some pinging is not all that unusual, but the way you word it it seems to be a much more severe case then what you normally see, unless you got some real strange riding habits.
If the dealer built the engine, have the dealer fix it. The first step would be to see if the reflash uploaded properly, it wouldn't be the first time the data got corrupted.
 

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This forwarded to me by my old wrench (and great bud) from Hawaii....

Fuels, Octane, Pre-ignition & Detonation

High-octane or premium gas burns slower than low-octane gas (regular gas). Therefore, combustion is slowed with premium gas. Slower combustion can prevent pre-ignition, or "pinging". Pre-ignition is ignition of the fuel/air mixture before the spark plug fires. The ping of pre-ignition sounds like marbles bouncing around inside the engine. The term "pre-ignition" is sometimes incorrectly used interchangeably with "detonation". The death rattle of detonation is an erratic and intense pressure wave that occurs shortly after TDC (top dead center) of the power stroke. When the air/fuel mixture is ignited by the spark plug, a combustion flame front spreads outward from the plug accompanied by pressure waves created by the combustion. Detonation is caused by the amplification of two pressure waves combining to form an intense wave "spike", which then bounces around the combustion chamber surfaces, causing very-high temperature spots that ignite a second flame front. The "knocking" sound of detonation results from this secondary ignition and it's pressure waves which greatly shock-stresses pistons, piston lands, rods, crank and bearings. Schlieren photography of Harley combustion chambers during actual engine operation has revealed that detonation is not the result of "colliding flame fronts" as some believe. Most everyone does agree, however, that severe detonation will quickly destroy an engine.

The octane rating system used in the USA is RON + MON/2, where RON is the Research Octane Number, and MON is the Motor Octane Number. The ratings are determined on a dynamometer for a particular fuel. The RON dyno test is done without a load on the motor, and the MON dyno test is done with a load on the motor. The two results are then summed and divided by 2 to determine the rating of the gas which is displayed at the gas pumps.

An engine's octane needs are influenced by several factors, especially the configuration of the engine (state of mechanical tune, i.e. - cranking pressure, valve timing, ignition timing, operating temperature, plug heat range, carbon deposits, etc.) and each engine has it's own distinct octane requirements for optimum operation. For example: If your engine only needs 89 octane to run properly without pre-ignition, the use of 91 octane will not increase performance! Conversely, the use of 87 octane, when 89 is needed, will result in preignition, overheating and poor performance. Once you have established the actual octane needs of your particular engine for ping-free operation, the use of higher octane gas is only wasted money!

Hope this helps a little

John "JFScheck" Scheck :D
 

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Discussion Starter #9
John and Hippo, I do feel this pinging is extreme, not mild or minimal, but very pronounced on acceleration when hot. The dealer did build the motor, so that's the place I'll head. The explanation of ping vs detonation is very much appreciated. This sounds more like pinging than detonation. Just for the heck of it, before the dealer gets the bike back, I will do 200 or 300 miles this weekend with some octane booster to check it's effect. If anyone is interested, I'll keep this story up to date over the next weeks.
 

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Sure, the responses from dealers are always interesting.

I have my own toughts on the matter.
 

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Discussion Starter #11
Hippo, a story you might enjoy, judging by your comment about your own thoughts. When I took my bike in to get the Screamin' Eagle Big Bore Stage 2 kit installed, (I bought the bike here, have business clients here, have had them service both my Road Kings etc, etc.) when I got the bike back, it ran like s#*t! They diagnosed an air leak at a new gasket position. When I called to check on the progress of the "fix" for the leak, the service manager sheepishly advised me that "honesty is the best policy, we didn't install the cams when we put in your Stage 2 kit..." This obviously explained the poor running since the ECM was flashed for the new cam profile. They've been real nice since then. This service trip to get the pinging evaluated will be the first they've had the bike since the 95" kit install. Hopefully the embarassment of the first incident will push them toward a solid investigation of the pinging trouble, time will tell.
 

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Well, they got their job cut out for them.

There are very few engine builders working at dealers, for the most part they just change parts.
Things like deck height and chamber volume not to speak of other things vary in production. The 203 and 204 cams they install with the stage packages are too mild for 95" packages and are very hard to keep from pinging in particular on EFI bikes. Ironically the most problems come with bikes where while stock the tolerances stacked up to make them strong. On the wooly bulls and 88"s you are much more likely to get away with it.
 

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Hippo, I have read this thread with great interest since I am considering a stage 2 for my 02 RK classic next spring. I'm clearly not a mechanic, although i have been involved in motorsports for most of my life. You stated that certain cams (I can't see the post now that I am typing this, but i think you said 204 & 204, were too mild and therefore contributed to pinging. Could you explain further, I wouldn't have guessed that.

thx, greg

ps, who might you recommend in SoCal to install a stage 2?
 

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It would take a small book, but in short when you up the displacement you are raising the compression ratio. Nominal chamber volume in the stock TC heads is 85cc, but they vary from about 82 to 88. Deck height spec is 0 but sometimes you see them as much as .020" off.

You can see how compression ratio can end up quite different from one basic 95" or even 88" to the next.

Stock head gasket thickness is about .052" and this gives excessive squish height that makes engines prone to pinging. If you use the preferred .032" gaskets to reduce this tendency you raise CR even more.

The smart way to build them is to use the higher CR but keep cranking pressure low by using more cam, ie a cam with later intake closing while keeping lift near stock in order to be able to use stock guides and springs.

People are intimidated by the fact torque is pushed higher up in the rpm range but they forget that it is more torque and it is just the peak that is pushed up.

While there may be others, if you are thinking dealer, there used to be a guy by name of Bill Pfitzenmaier that worked at the dealer in Marina del Rey. Old school engine builder. Not sure if he is still there and good luck getting him to work on a particular bike, but you can try.
 

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If you are involved in motorsports you know better then waste your money on this sort of thing without using a good set of ported stock heads, not the ones dealers sell.

Head(s) makes people happy in more then one way. :D
 

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There are any number of threads on oil coolers. As far as to specifically eliminate the pinging it would be really minimal at best.
Even if they reduce oil temperature there is not enough cylinder head temperaure reduction to be worth mentioning. this is mainly controlled by the state of tune on an air cooled engine.
 

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Now Hippo you've got me worried. I had my jugs bored to 95", and bought a set of the vortec heads from SBC last week. When I spoke to Charlie he said the SE-204 was a good match. Now I haven't hammered my ride yet, as I want to break it in properly. So I can't tell you if I've got any detenation or "pinging". I'm running a carb. Am I begging for problems.

On a side note. I can tell you so far it is a lot louder. I can set off my neighbors car alarm at will. I can also tell you it feels like she wants to get to the red line in short order. :) I can hardly wait to get some miles on.
 

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You didn't say what model bike they are on.
If you told him up front you were going to run these cams he likely set the heads up to run with them.
The original comment as you can see referred to stage builds that do not include heads. Stock heads with stock valve sizes are corked up big time and this tends to promote heat build up. Our heads flow extremely well where it matters most and keep charge velocity up and this helps to somewhat reduce heat buildup at a given output level.
We also use and recommend the cometic .032" head gaskets. This marginally increases compression but very significanly reduces squish height. This goes a long way in minimizing detonation on TC's, despite the small compression increase.
Given all the above reasons, and in particular the fact you run a carb, you shouldn't have a problem if the carb is set up anywhere close to right.

No question the bikes pull like locomotives with these heads, and they have better midrange then most others everything else being equal.

Usually we tailor things to what people want to run, but I still recommend at least the 37b Andrews cam, and prefer the 44 or 50 personally.
 
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