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Old 28th March 2019, 09:35   #1
zedhed
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Default 0.5 spark gap

Still got this annoying hesitation folks,and was reading some old threads regarding the 0.5 spark gap.is this really the way to go?,I mean thinking about what someone said about it running perfectly fine from the factory on a 1.0mm gap makes me think if I’m just masking another problem😏


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Old 28th March 2019, 10:16   #2
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Reducing the gap from the MGR spec down to 0.5-0.7mm is frequently found to fix hesitation when accelerating, but if yours is fine as it is, it's not necessary. I reduced mine to 0.7mm when I last changed the plugs, but I had no specific reason to do it. I'd read all the threads and simply thought, why not? As vehicles get older, there's a natural tendency to experiment and vary away from what the manufacturers specified. But many of the reasons are arbitrary I suspect.

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Old 28th March 2019, 12:22   #3
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Mine does still have a hesitation problem,even after re gapping plugs to 0.7,so now thinking of doing it again to 0.5.have already changed one coil pack,so might do the other aswell👍


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Old 28th March 2019, 16:07   #4
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If you replace your plugs, make sure that they are genuine. There are a lot of fake spark plugs out there and misfires is typical of faults with them. I had a Honda 750 bike with dodgy NGK plugs in it which took ages to fathom. I found pics on t'interweb of fake plugs and mine were. A good set from a reputable supplier and the misfire was gone!
https://www.google.com/search?q=fake...=1920&bih=1064
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Old 28th March 2019, 19:49   #5
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Quote:
Originally Posted by zedhed View Post
Still got this annoying hesitation folks,and was reading some old threads regarding the 0.5 spark gap.is this really the way to go?,I mean thinking about what someone said about it running perfectly fine from the factory on a 1.0mm gap makes me think if I’m just masking another problem��


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Reasons.----From the factory the insulation of the leads is good. As the leads age the resistance to breaking down under load decreases.

Making the gap smaller allows the spark to jump at a LOWER voltage thus taking the strain off the leads.

Big gaps mean higher voltages and the spark quite often prefers to jump out of the side of the lead to the nearest earth point than across the one mil plug gap.

Higher revs make greater combustion chamber pressures. At higher revs with poor condition plugs the spark will track down inside the plug and not jump the gap and ignite the fuel.

Generally the need to reduce the gaps to get the fuel to fire is the first indication of spark lead problems or dying plugs.

Last edited by COLVERT; 29th March 2019 at 13:04..
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Old 29th March 2019, 09:14   #6
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The boost control valve on the side of the airbox can cause hesitation if faulty.
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Old 29th March 2019, 09:46   #7
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Quote:
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The boost control valve on the side of the airbox can cause hesitation if faulty.


But would it hesitate before turbo spooling?


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