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Author Topic: Changed plugs now no power  (Read 3836 times)

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Offline TwoTired

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Re: Changed plugs now no power
« Reply #25 on: July 05, 2011, 11:34:56 PM »
You don't really need a dwell meter.  All it is used for is to set the point gap, which you can do with a thickness gauge.

Cheers,
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Offline Bahumut

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Re: Changed plugs now no power
« Reply #26 on: July 06, 2011, 07:30:01 PM »
Well, I'm on broke-mode, so I went to harbor freight, bought a timing light and got to work.  And man did I learn a lot today playing with that light!

 I spun the timing plate counter clockwise a little bit to get the F mark to line up with the casing mark and went to work.  After rechecking the gap I screwed everything down and back together went on a test run and not only did it run better, my tach actually swept past 4K for some reason.  The bike still seems to stutter at 3/4 to WOT though, which it DIDN'T do last week, and the sound from the intakes sounds like it's drowning or something.  The bike will pull (eventually) past 80 which is as brave as I'm to take it. 

So, power is back, but something is still up...
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Offline Spanner 1

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Re: Changed plugs now no power
« Reply #27 on: July 06, 2011, 08:16:44 PM »
So the timing light showed both points opening at their respective F marks @ idle ( 1100 rpm, no more) but did you check for max. advance @ 2,500-3,000 rpm with your strobe light showing the // marks in the 'window' ??
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Offline Bahumut

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Re: Changed plugs now no power
« Reply #28 on: July 07, 2011, 05:36:41 AM »
yeah, the F1.4 (2.3) would rotate counter clockwise and stop at the ]] marks to the right of the numbers under revving.   I didn't purposely check that, I just noticed that it did that and was consistent across all four plugs with the timing light.  One thing to note however is that it takes a while for the revs to come back down on their own.  On my fuel-injected bikes, you hit the throttle and it revs up but goes back pretty quickly.  This CB seems to take a lot longer than a split second to come down after shutting off the throttle. 

I'm gonna pull the carb bank off tonight and re clean them, just in case I have some crap in there or something.
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Offline Bahumut

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Re: Changed plugs now no power
« Reply #29 on: July 07, 2011, 05:48:30 AM »
You know what.. I'm thinking I advanced the timing a little tooo far.  I'm going to go back to there and adjust it once more.  I'll let you know how the bike behaves after all this rain stops...
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'08 KTM 690 Duke - teacher of backin' it in on public streets and collector of traffic tickets

Offline Spanner 1

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Re: Changed plugs now no power
« Reply #30 on: July 07, 2011, 11:24:32 AM »
Be careful with the strobe as anything above idle rpms will show advanced timing as the advancer may be already turning the cam ( which would be normal )  ;)
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Offline dave500

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Re: Changed plugs now no power
« Reply #31 on: July 07, 2011, 12:52:37 PM »
ignition sorted,,now play with pods and jetting.
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Offline Bahumut

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Re: Changed plugs now no power
« Reply #32 on: August 09, 2011, 01:48:55 PM »
It's been a month, I figured I'd fill y'all in.

First off, thanks to everyone for helping me sort out my issues (with the bike, my personal ones are a whole 'nother thing).

It ended up being a combination of problems that was keeping my bike from running right.  The timing was off for sure but when I took the carbs apart, one of the main jets was sitting in the bottom of the float bowl!

Now i have another problem, but I'll do a search first and start a new thread if I need to.

Thanks again everybody!
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Offline Bankerdanny

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Re: Changed plugs now no power
« Reply #33 on: August 09, 2011, 01:58:00 PM »
That heppened to me right as I was getting my bike on the road, I pulled a float bowl and found a jet sitting at the bottom.
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Offline dtmmil

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Re: Changed plugs now no power
« Reply #34 on: August 09, 2011, 02:31:24 PM »
Did you get your 1-4 trouble fixed? Sometimes with the pods the airflow from the sides will kinda rob the air from those carbs with pods. If you didn't, next time your out try moving your legs around to deflect the air at those carbs, or cover the outsides of the pods with some tape or something and try again.
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Offline dave500

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Re: Changed plugs now no power
« Reply #35 on: August 09, 2011, 02:57:15 PM »
 I don't have that tool yet.  I guess I know where my lunch money for the week is going...

ive eaten cold boiled potatoes and those corn disc styrofoam things for lunch at work for a fortnight to save for things before!
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Offline Bahumut

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Re: Changed plugs now no power
« Reply #36 on: August 09, 2011, 03:20:59 PM »
Quote from: dave500 on August 09, 2011, 02:57:15 PM
I don't have that tool yet.  I guess I know where my lunch money for the week is going...

ive eaten cold boiled potatoes and those corn disc styrofoam things for lunch at work for a fortnight to save for things before!

wha----?
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'77 CB550K - current teacher of patience and things mechanical

'08 KTM 690 Duke - teacher of backin' it in on public streets and collector of traffic tickets
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