Author Topic: cb750 miss fire HELP  (Read 1668 times)

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werdna

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cb750 miss fire HELP
« on: May 28, 2005, 06:03:29 AM »
Hi all

My cb750 has started to miss fire at around 5000rmp, I've checked float hight and re tuned the carbs but no difference  any idea's please?

Andy
England

MetalHead550

  • Guest
Re: cb750 miss fire HELP
« Reply #1 on: May 28, 2005, 07:07:17 AM »
Does the bike have the original induction system?  Any upgrades or repairs lately?  How old is the gas?  What do the plugs look like?  Alot can be decifered about an engine's running condition by examining the plugs.  Check out this cool page that TwoTired has been posting.  Very usefull.
http://www.dansmc.com/Spark_Plugs/Spark_Plugs_catalog.html

Oh...and Welcome!

Offline TwoTired

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Re: cb750 miss fire HELP
« Reply #2 on: May 28, 2005, 12:10:34 PM »
5000rmp?
That's a lot of Royal Mounted Policemen.  And, in England no less.  I think I'd check the accuracy of your indiicator.  Or, have you been a really bad boy? :)

Seriously, you need to start with a thorough tune-up with the bike.  Plugs points, timing, tappets, cam chain, air filter need regular attention. This is called routine maintenance.  And, it can prevent symptoms that you've described.  If you are still having problems after a basic tune-up, give us another post.  Anyway, this will prevent us from suggesting some obvious things and eliminate some variables.  Have you read your plugs to determine the misfireing cylinder?

Cheers,
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.