Weak / intermittent spark

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freeserve
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Weak / intermittent spark

Post by freeserve » Tue Jul 24, 2018 10:44 am

Hello,

I am after some troubleshooting help please, :peace:

Bit of background:
This is a very long term project, +5 years now. I purchased the bike as 5 boxes of bits and frame witch turned out to be UK spec.

The bike is now built (mostly) and is, or was just about a runner. After getting the bike fired up I noticed it was not reving past 4 - 5K, when I tried to push past this the bike would try to stall but I also noticed it was not running on one of the cylinders. I put this down to Carbs which are beyond me so I got them all fixed up by GF Racing. awesome job :plus:

Crabs all sorted but now it refusing to fire up, after checking for spark I realised I had at best a very weak spark but most of the time I had no spark at all. Plugs are new, HT leads are new, coil packs are tested in accordance to the manual.

Not sure where is the best place to start with this issue so any help would be very much appreciated bighug

Regards,

John

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NGneer
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Re: Weak / intermittent spark

Post by NGneer » Tue Jul 24, 2018 1:31 pm

1. Check all your earths and plug connections (Have you painted or powder coated bits like the sub frame which could now be preventing a good earth connection?)
2. Try working through this (http://www.electrosport.com/media/pdf/f ... iagram.pdf) as that will guide you through checking most of your electrical system. If you get through that without finding anything wrong then start looking at the more obscure options such as the ECU possibly breaking down.

magg
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Re: Weak / intermittent spark

Post by magg » Tue Jul 24, 2018 1:52 pm

Speedo plugged in?

freeserve
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Re: Weak / intermittent spark

Post by freeserve » Tue Jul 24, 2018 1:57 pm

magg wrote:Speedo plugged in?
Yes mate.

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freeserve
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Re: Weak / intermittent spark

Post by freeserve » Tue Jul 24, 2018 1:58 pm

NGneer wrote:1. Check all your earths and plug connections (Have you painted or powder coated bits like the sub frame which could now be preventing a good earth connection?)
2. Try working through this (http://www.electrosport.com/media/pdf/f ... iagram.pdf) as that will guide you through checking most of your electrical system. If you get through that without finding anything wrong then start looking at the more obscure options such as the ECU possibly breaking down.
Thanks, I will work through it and see if it helps.

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moforockband
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Re: Weak / intermittent spark

Post by moforockband » Tue Jul 24, 2018 4:29 pm

check the 12v and ground at the cdi. Also check that the coils both have 12 volts, and that the grounding wire on each coil measures 0 ohms when continuity checked back to the cdi (unplugged).
Obviously check that the sidestand switch/neutral cutout isn't causing you any grief.

freeserve
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Re: Weak / intermittent spark

Post by freeserve » Tue Jul 24, 2018 4:42 pm

moforockband wrote:check the 12v and ground at the cdi. Also check that the coils both have 12 volts, and that the grounding wire on each coil measures 0 ohms when continuity checked back to the cdi (unplugged).
Obviously check that the sidestand switch/neutral cutout isn't causing you any grief.
Thanks, I will check it out.

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Neosophist
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Re: Weak / intermittent spark

Post by Neosophist » Sun Jul 29, 2018 4:35 pm

what ignition box are you using? jdm boxes have a speed limiter which cuts the rev limit after 5500rpm.

apart from that pretty much what everyone else has said, since its a new build check the earths, re-check battery voltage.. kill switch.. try some other plug

strange one!
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...

freeserve
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Re: Weak / intermittent spark

Post by freeserve » Sun Jul 29, 2018 4:42 pm

Standard unit, thanks everyone. I will check everything over the next few days.

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