Author Topic: Won't fire  (Read 992 times)

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Offline crue98

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Won't fire
« on: June 29, 2011, 07:35:59 AM »
I'm new to the 750's. I have just bought 1975 750f. Rode it a couple times just fine. Then yesterday I shut it off after riding and a couple minutes later I went back out the adjust the idle, it wouldn't fire. Check a few things and found it had no spark, but had power the ignition and the headlight and panel lights. Don't know where to go from here, again just a noob. Any advice would be great

Offline MoMo

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Re: Won't fire
« Reply #1 on: June 29, 2011, 07:52:29 AM »
First off, welcome.  Do you have electronic or points?  I am assuming points, which are probably dirty and need to be cleaned with a point file, electronic cleaner and the blown off with air. That is the most common problem. Check voltage at the black/white wire going to the coils, if there it is probably dirty points...Larry

Offline crue98

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Re: Won't fire
« Reply #2 on: June 29, 2011, 08:28:04 AM »
Thanks Larry...we will check that. The bikes at a buddies house so we will do that when we have a chance.

Offline crue98

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Re: Won't fire
« Reply #3 on: June 29, 2011, 08:30:18 AM »
i forgot......it's points. and they looked very clean when we pulled the cover off.

Offline flybox1

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Re: Won't fire
« Reply #4 on: June 29, 2011, 08:56:16 AM »
they looked clean, and i just cleaned them as you kindly suggested and it didnt help my situation are 2 different things... ::)

how new is your battery and is it fully charged? whats your voltage?
check your fuses?  cleaned and treated all yoour connectors?  got a multimeter?
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

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Offline crue98

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Re: Won't fire
« Reply #5 on: June 29, 2011, 09:03:51 AM »
It just happened last night...we just try little easy stuff at first. When we have a chance we will do all the suggested thing that you guys have mentioned.....thanks again. We will eventually do the cleaned up wiring diagram that was found on the forum, since its more of a simple bike.

Offline gnarlycharlie4u

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Re: Won't fire
« Reply #6 on: June 29, 2011, 09:10:40 AM »
do you have a multimeter? checking continuity of connections and power would be a good place to start.

The easy check is to pull plugs (one at a time) and while trying to start it hold the plug tip against the head (away from plug hole and with carbs drained and fuel off).
If they produce a white/blue spark you're probably good there and it's time to start looking elsewhere.