Suzuki Quadracer HQ
LT500R Quadracer => LT500R - Engine => Topic started by: Rainman56 on February 12, 2013, 03:07:35 pm
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I originally asked because in general center is best but I wasn,t sure how much clearance there was.Purchased my 500 packed up in pieces so I had nothing to go by.If you have the room go for it,not sure how much benefit you,ll gain but would be interesting to know.:)
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maybe ill be the first
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NGK makes some shorty syle plugs that might clear the frame. Be interesting if someone wanted to tinker with a coolhead having a custom dome with the sparkplug hole centered and straight if it made enough more hp to be a worthy mod.
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dont aplogize. just dont expect me to pay for the online tutoring:). so moto, would you say idealy, given allowing chassis dimensions, would a vertical spark plug be better? im assuming the only time when an angled plug would be better/practical is if there were 2 plugs in 1 cylinder.
curiosity sometimes eats at me.
I would say straight and centered in the combustion chamber is best unless testing dictates otherwise on a particular engine.
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dont aplogize. just dont expect me to pay for the online tutoring:). so moto, would you say idealy, given allowing chassis dimensions, would a vertical spark plug be better? im assuming the only time when an angled plug would be better/practical is if there were 2 plugs in 1 cylinder.
curiosity sometimes eats at me.
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whoa! thats a whole lot of theory right there. i guess i just wanted to know if there would be any benefit to have the plug vertical in the head. i noticed cr500 have there's angled back towards the intake side. anywho, thanks for the info!
Sorry for such a long answer. This could also be added to my above response.
Manufacturing the dome so the the spark plug is in the center of the combustion chamber is desirable. It also simplifies machining and reduces manufacturing cost.
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...and when Kyle speaks, he gives good head (specifications)
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Oh yeah. When Jerry speaks, he gives good info.
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whoa! thats a whole lot of theory right there. i guess i just wanted to know if there would be any benefit to have the plug vertical in the head. i noticed cr500 have there's angled back towards the intake side. anywho, thanks for the info!
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:o
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The only reason the spark plug is angled is so that the spark plug and spark plug cap can be removed. The angled spark plugs have the electrode located so close to the center of the combustion chamber it does do not effect flame propagation. Locating the spark plug in another location other than the center of the combustion chamber will effect burn speed and when the combustion process is complete. We want to complete the combustion process as quickly as possible.
Detonation is more apt to occur as the time for complete combustion to occur increases.
Remember the basics: the pressure front travels at the local speed of sound in the combustion chamber, the flame speed is controlled by the turbulent intensity and heat travels at the speed of light. Flame speed is relatively slow as compared to pressure and heat velocity.
The speed of sound is governed by pressure and temperature. The speed of sound in free air at sea level is approximately 1100 ft per second. The speed of sound in the exhaust at export opening can be over twice the speed of sound in free air. The speed of sound in the combustion chamber at peak pressure and temperature can be many times the speed of sound in the exhaust. Knowing these facts we can see that the pressure distribution on top of the piston is distributed evenly at any time during the combustion process.
Spark plug location has nothing to do with pressure distribution on the top of the piston unless we are strictly being theoretical. The instantaneous effect of the pressure distribution on top of the piston would not cause the piston to rock unless the piston was mass-less. Piston rock is controlled by piston pin offset, offset of the cylinder axis over the crankshaft, connecting rod length, the length of the piston skirts, and piston skirt clearance.
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It's so you know that the cylinder is on the right way.
If the plug is pointing left, you're good.
If the plug is pointing right, you put it on backwards.
This is the reason why. I put a cylinder on once and thought the spark plug hole was facing the wrong way. Then I noticed the exhaust was pointing to the rear. Ram air FTW
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It's so you know that the cylinder is on the right way.
If the plug is pointing left, you're good.
If the plug is pointing right, you put it on backwards.
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hey sorry to gave dig this, but why are the spark plugs offset angled? is the official answer for ease of access? ive always wanted to know
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...I need to read all these threads before I post.
Seems you guys already have it figured out :)
Not 100% yet,still all ears.:)
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...I need to read all these threads before I post.
Seems you guys already have it figured out :)
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Thanks Dezsled,you,ve been a big help.Looks pretty tight in there.Looks like the angled plug is for clearance issues.Looks like I,ll be leaving things as they are and just fixing the squish. +k2
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This is the best I've got atm......
(http://i83.photobucket.com/albums/j300/Dezsled/photo90.jpg)
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[quote author=Stpltn250r link
The reason its angled the way it is is so when the spark plug fires the flame front does not rock the piston from front to back, it aims it parallel to the wrist pin so there is no rock in the piston. No one wants the piston to rock back and forth at 8k rpms do they??
[/quote]
Generally piston rock is dealt with more so by the pin location being offset on the piston itself no???
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So does anyone have a clear up close pic of a Zilla engine in the quad to show how much clearance there is?Preferably with the fuel tank off.
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there is way more than enough room for clearance on the plug. the domes in the cool head also turn in any direction but are still at an angle. its fine the way it is. no need to reinvent the wheel. T
The reason its angled the way it is is so when the spark plug fires the flame front does not rock the piston from front to back, it aims it parallel to the wrist pin so there is no rock in the piston. No one wants the piston to rock back and forth at 8k rpms do they??
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Checked out a few more pics and beings a cool head has the plug on an angle I,m pretty sure it must be for clearance.If there was room to move the plug to a better location(the center) I,m sure the aftermarket would have done it already.
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Yeah I'd hate to steer you in the wrong direction.
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Hard to tell in the pic but looks like it may be too tight up against the arch/backbone?
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This pic might give you an idea of the space available
(http://i83.photobucket.com/albums/j300/Dezsled/photo39.jpg)
If it was straight up removing the plug might be a problem
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Is there enough room to remove it if it were to be placed straight up in the center of the head?Like I said my 500 was purchased in pieces so I don,t know how much clearance it has.Basically would the plug be able to be removed and installed if it was dead center straight out?
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It looks like its at an angle to easily remove the spark plug.
Oops it's already been answered.... Duhhh
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yes its offset. assuming to remove it easier when bike is fully assembled.
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Anyone?
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Bought my Zilla in pieces so i don,t know but is the spark plug off center in the head for clearance reasons?Doing some head mods and if there is clearance I,m going to weld and move the plug hole to the center while modifying the dome/squish are.
Like I said wondering if the plug being offset is for clearance issues?