Which way? Spark Plug Slant?
- Thread starter gokart25
- Start date
It might be best to position the plug so it gets most benefit of the swirl effect within the chamber, for ignition and cooling purposes.
I like how Bairdco has mounted his coil down under the motor, and runs the spark lead up to a front leaning plug. makes for a cleaner look, not having the coil hanging around in the front of the frame... imo
Not sure how good it is for the coil to be in the drip and grime zone, though...
...there are a number of builders who have noted more problems with the slant plug heads on their engines... you may wish to review those posts...
Best
rc
I like how Bairdco has mounted his coil down under the motor, and runs the spark lead up to a front leaning plug. makes for a cleaner look, not having the coil hanging around in the front of the frame... imo
Not sure how good it is for the coil to be in the drip and grime zone, though...
...there are a number of builders who have noted more problems with the slant plug heads on their engines... you may wish to review those posts...
Best
rc
What ever suites your fancy. If there is a proper way (front or rear) I doubt that you could tell any difference in performance.
I like to pull the head and check the cylinder regardless of type, but I always reverse the slant to go forward when I put it back on.
Besides getting the plug wire away from the carb side and the CDI away from motor heat, I replace all the stock wiring from the magneto to the kill button through my unique CDI ignition keylock addition.
This is not the best bike example because it has 2 split cables running down the front tube for the rear brake and derailleur where I like to run the motor wire, it does show why I point the plug to the front ;-}
Besides getting the plug wire away from the carb side and the CDI away from motor heat, I replace all the stock wiring from the magneto to the kill button through my unique CDI ignition keylock addition.
This is not the best bike example because it has 2 split cables running down the front tube for the rear brake and derailleur where I like to run the motor wire, it does show why I point the plug to the front ;-}
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i've always put spark plug facing forwards, my bike frames don't have much room so that's the only way. Does a straight head give more performance?
I used to put the plug forward, until I realized that there are more cooling fins on the opposite side of the plug that would do the engine much more good over the exhaust port (where the engine gets hotter).
Pirate billet heads are made to have the plug facing forward.
Pirate billet heads are made to have the plug facing forward.
That's a good point, Venice.
...for a stock slant head.
and could still tuck the cdi box under the motor.
rc
...for a stock slant head.
and could still tuck the cdi box under the motor.
rc
Alright. Well I just got a slant head for my build. Its turning out to be a little bit of a tight fit. But it will fit if i flip the head to have the slanted spark plug facing forward.
Im glad I found this thread before I was going to post the question. It always pays to search the threads before posting!
Im glad I found this thread before I was going to post the question. It always pays to search the threads before posting!
KC,
That's got top be the neatest wiring job "outside the tubes" Ive ever seen
Props grass hoppa
Thanks Jumpa, cable and wiring is a bit of trademark of mine ;-}
The motor to CDI box wire is different, I use fatter 16G shielded 115V AC wire. It just fits the motor wire hole and gets everything the dyno can make to the CDI.
To answer your question jrol22, yes, any key switch with a rating of 24VAC 1A or better is plenty, just put it between the blue motor CDI wire and the CDI's blue wire in.
The hard part is where to mount it.
Though any kind of switch anywhere between the motors dyno and CDI will prevent the motor from starting, if it can be easily hot wired to bypass the switch it won't be as effective.
I use a 4 tumbler cash register switch that lets you remove the key in both the on and off positions, and then mount it as well as the wire ends in a Radio Shack hobby box epoxied onto the top of the CDI itself on every build.
The switch lock may be able to be picked, but you won't be able to hotwire it, and if you break the case open it takes the CDI wires with it so they would need a new CDI.
Being in the business here if someone does steal a local customer of mines bike and they can't make it start they are likely to contact me, especially since my name and number are on each one.
Suffice it to say that my customer will get his bike back if the thief brings it by here ;-}
But to get back to the Spark Plug Slant topic...
Though Venice has a valid point about where the head cooling fins are located plus the 'non-symmetrical' look of a reversed 48cc Skyhawk head to the trained eye like this example of my latest build, even riding here in Phoenix in 110F summer heat that fin orientation is meaningless.
I got a little fancy with this latest build pics, do you guys think it's 'a bit too much' or kinda cool?
Regardless it does show why I do what I do and how it looks.
I use the stock throttle kill button, I just replace the wire from it with that regular pull cable sized black wire and run it to my CDI box.
The motor to CDI box wire is different, I use fatter 16G shielded 115V AC wire. It just fits the motor wire hole and gets everything the dyno can make to the CDI.
To answer your question jrol22, yes, any key switch with a rating of 24VAC 1A or better is plenty, just put it between the blue motor CDI wire and the CDI's blue wire in.
The hard part is where to mount it.
Though any kind of switch anywhere between the motors dyno and CDI will prevent the motor from starting, if it can be easily hot wired to bypass the switch it won't be as effective.
I use a 4 tumbler cash register switch that lets you remove the key in both the on and off positions, and then mount it as well as the wire ends in a Radio Shack hobby box epoxied onto the top of the CDI itself on every build.
The switch lock may be able to be picked, but you won't be able to hotwire it, and if you break the case open it takes the CDI wires with it so they would need a new CDI.
Being in the business here if someone does steal a local customer of mines bike and they can't make it start they are likely to contact me, especially since my name and number are on each one.
Suffice it to say that my customer will get his bike back if the thief brings it by here ;-}
But to get back to the Spark Plug Slant topic...
Though Venice has a valid point about where the head cooling fins are located plus the 'non-symmetrical' look of a reversed 48cc Skyhawk head to the trained eye like this example of my latest build, even riding here in Phoenix in 110F summer heat that fin orientation is meaningless.
I got a little fancy with this latest build pics, do you guys think it's 'a bit too much' or kinda cool?
Regardless it does show why I do what I do and how it looks.
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it doesn't matter which way the plug is slanted.
I flipped my head around for more frame clearance, but I ran the engine on the bike with the head in both configurations.
I went from a rear slanting plug to a front slanting plug, and there's no difference in the way it runs, or how hot it gets.
I flipped my head around for more frame clearance, but I ran the engine on the bike with the head in both configurations.
I went from a rear slanting plug to a front slanting plug, and there's no difference in the way it runs, or how hot it gets.
