sparkplug gap
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Tourer
Joined: Jan 2015
Posts: 344
Likes: 4
From: USA
sparkplug gap
What's the gap spec for the oem sparkplug on my '15 RGS? Yes...I do indeed have a shop manual and I'm the other idiot who doesn't carry my owner's manuals with me...and I'm faaaar away from either. So please provide me with the specs if you have it and I'll buy you a beer and a burger if I see you!
Thread Starter
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Tourer
Joined: Jan 2015
Posts: 344
Likes: 4
From: USA
Thanks! How critical is the difference when gaping them from 38 through 40...in other words, is 38 better than 40...or the other way around? Or is is a particular motor specific issue?
Stellar HDF Member
Joined: Sep 2013
Posts: 3,490
Likes: 610
From: USA
Spark plug type
6R12
Spark plug size
12 mm
Spark plug gap
0.038-0.043 in.
0.97-1.09 mm
Spark plug torque
12-18 ft-lbs
16.3-24.4 Nm
Road Warrior
Joined: Nov 2014
Posts: 1,962
Likes: 140
From: NY
If using cheap std design plugs gap to .038" because as the plugs wear over time the Gap widens and when you start at tighter .038" your good as plugs wear to .039" & .040" till plugs (ground strap and center electrode) wear past .040" spec.
But if your starting out either dbl plat or iridum plugs that have basically no plug wear (gap wear) for example, dbl plat can go up to 100k miles and iridium well over 100k miles (motor in good cond with proper tune) before requiring replacement i'd rec going with .040" to expose more spark kernal to the combustion chambers for a bit better more efficient burn since gap will not be wearing / widening when using more durable dbl plat or iridium plugs that outlast std plugs by 3x-4x respectively.
But with that said plug mfgs state not to touch/chk gap on their dbl plat or iridium plugs because they calim they are properly gaped from factory and to not damage the plat or iridium plugs when trying to chk gap.
Even though mfg rec's not checking gap on dbl plat of iridium plugs prior to install i do it (Carefully!) for my own cars or bikes (vehicle's i work on for other people too) not ever damaging them and have in fact found a few plugs over the yrs that were in fact way out spec'd gap range which i corrected prior to install with again,no i'll affects.
I also apply some anti seize on plug threads too because dbl plat or iridium plugs will be in the motor much longer due to their 3x and or 4x longer (by design) srv'c life ,but,thats as long as the motor is in good cond ,has proper tune along with coil 7 plug wires also being on good cond too .
That's because if motors not in good cond being tired using oil ,the tune if off being too rich or plug wires & or coil are tired or worn out all of which can cause the plugs to get dirty much quicker and or be fouled significantly reducing their srv'c life.
Scott
Last edited by wscott; Jan 28, 2016 at 10:30 PM.
Road Master
Joined: Apr 2015
Posts: 1,013
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From: Elk Grove, California
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Tourer
Joined: Nov 2007
Posts: 442
Likes: 4
Plug will last longer and stay in range. Book says 38-43 if your motor is stock go 40. If compression is greater than stock go 38. Some even go 35
Last edited by vbx07; Jan 29, 2016 at 07:00 AM.
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Road Master
Joined: Jan 2013
Posts: 967
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From: Woodland Park, Co
===================
If using cheap std design plugs gap to .038" because as the plugs wear over time the Gap widens and when you start at tighter .038" your good as plugs wear to .039" & .040" till plugs (ground strap and center electrode) wear past .040" spec.
But if your starting out either dbl plat or iridum plugs that have basically no plug wear (gap wear) for example, dbl plat can go up to 100k miles and iridium well over 100k miles (motor in good cond with proper tune) before requiring replacement i'd rec going with .040" to expose more spark kernal to the combustion chambers for a bit better more efficient burn since gap will not be wearing / widening when using more durable dbl plat or iridium plugs that outlast std plugs by 3x-4x respectively.
But with that said plug mfgs state not to touch/chk gap on their dbl plat or iridium plugs because they calim they are properly gaped from factory and to not damage the plat or iridium plugs when trying to chk gap.
Even though mfg rec's not checking gap on dbl plat of iridium plugs prior to install i do it (Carefully!) for my own cars or bikes (vehicle's i work on for other people too) not ever damaging them and have in fact found a few plugs over the yrs that were in fact way out spec'd gap range which i corrected prior to install with again,no i'll affects.
I also apply some anti seize on plug threads too because dbl plat or iridium plugs will be in the motor much longer due to their 3x and or 4x longer (by design) srv'c life ,but,thats as long as the motor is in good cond ,has proper tune along with coil 7 plug wires also being on good cond too .
That's because if motors not in good cond being tired using oil ,the tune if off being too rich or plug wires & or coil are tired or worn out all of which can cause the plugs to get dirty much quicker and or be fouled significantly reducing their srv'c life.
Scott
If using cheap std design plugs gap to .038" because as the plugs wear over time the Gap widens and when you start at tighter .038" your good as plugs wear to .039" & .040" till plugs (ground strap and center electrode) wear past .040" spec.
But if your starting out either dbl plat or iridum plugs that have basically no plug wear (gap wear) for example, dbl plat can go up to 100k miles and iridium well over 100k miles (motor in good cond with proper tune) before requiring replacement i'd rec going with .040" to expose more spark kernal to the combustion chambers for a bit better more efficient burn since gap will not be wearing / widening when using more durable dbl plat or iridium plugs that outlast std plugs by 3x-4x respectively.
But with that said plug mfgs state not to touch/chk gap on their dbl plat or iridium plugs because they calim they are properly gaped from factory and to not damage the plat or iridium plugs when trying to chk gap.
Even though mfg rec's not checking gap on dbl plat of iridium plugs prior to install i do it (Carefully!) for my own cars or bikes (vehicle's i work on for other people too) not ever damaging them and have in fact found a few plugs over the yrs that were in fact way out spec'd gap range which i corrected prior to install with again,no i'll affects.
I also apply some anti seize on plug threads too because dbl plat or iridium plugs will be in the motor much longer due to their 3x and or 4x longer (by design) srv'c life ,but,thats as long as the motor is in good cond ,has proper tune along with coil 7 plug wires also being on good cond too .
That's because if motors not in good cond being tired using oil ,the tune if off being too rich or plug wires & or coil are tired or worn out all of which can cause the plugs to get dirty much quicker and or be fouled significantly reducing their srv'c life.
Scott
