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I posted earlier with tuning problems/dead cylinder, chasing electrical. After replacing the caps, i have proper resistance on the wires, and battery was low charge too -- maybe replace it?

The bigger discovery was that the cam/valve timing was WAY off. Short of a carb rebuild, i thought i'd check the timing, so i removed the covers last night, put the crankshaft at TDC1 and the cams were totally off. After a ()#*$&(#*$ of a job, i put them on properly. Without any feeler gauges (doh!) i couldn't check the valve clearance. Also, i have electronic ignition, and today ordered the spyglass timing plug to do strobe timing. Even advancing by enging rpm/ear, the bike idles/runs WAY better. I also synched the carbs last night after valve timing for good measure. I was already able to bring the idle screws back close to factory setting (no idle drop for this year).

I'm convinced the #1 cylinder noise was from timing. Doesn't hurt i also ran some Techron in the tank, which smoothed it out. I'm sure with proper advance/carb synch, the bike will run great! Only 60k km on it. Hopefully no engine damage (bent rod?) was done by being so out of tune.

One major question: the bike has OEM mufflers with baffles removed. This will certainly cause a lean condition, not to mention noise. Can i retrofit these mufflers with baffles? Seems the tips are only 4", too short for any aftermarket ones. I've heard the Gl1000s don't tune very well without proper backpressure.
 

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Sorry, dont' have an answer for you, but I have a 79 with aftermarket pipes and I was wondering the same thing about tuning and backpressure. Thanks for bringing up that topic.
 

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How did the belt timing go off mag? Did you replace the belts yourself or did you buy the bike like this? Instead of meddling with baffles it might be cheap enough to get a used set on ebay.
 

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On my 1200 with modified (open) mufflers it turns out that the mixture is right where it's supposed to be. My bike was running too rich with the stock mufflers.

The only way to find out for sure with your bike is to do a high RPM plug check or use an air/fuel meter.

Vic
 

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mag wrote:
I posted earlier with tuning problems/dead cylinder, chasing electrical. After

I'm convinced the #1 cylinder noise was from timing. Doesn't hurt i also ran some Techron in the tank, which smoothed it out. I'm sure with proper advance/carb synch, the bike will run great! Only 60k km on it. Hopefully no engine damage (bent rod?) was done by being so out of tune.

One major question: the bike has OEM mufflers with baffles removed. This will certainly cause a lean condition, not to mention noise.
1.) Probably was the cause of noise. Goldwings are bad for "valve noise" that is actually exhaust system noise.

2.) Mufflers do not control fuel mixture, carburetors do. Noise - yes.
 

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Dave Campbell wrote:
mag wrote:
I posted earlier with tuning problems/dead cylinder, chasing electrical. After

I'm convinced the #1 cylinder noise was from timing. Doesn't hurt i also ran some Techron in the tank, which smoothed it out. I'm sure with proper advance/carb synch, the bike will run great! Only 60k km on it. Hopefully no engine damage (bent rod?) was done by being so out of tune.

One major question: the bike has OEM mufflers with baffles removed. This will certainly cause a lean condition, not to mention noise.
1.) Probably was the cause of noise. Goldwings are bad for "valve noise" that is actually exhaust system noise.

2.) Mufflers do not control fuel mixture, carburetors do. Noise - yes.

 
Doesn't lack of backpressure from removed baffles cause more airflow than the bike is jetted for, thus leaning out effectively?
 

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weewillywing wrote:
How did the belt timing go off mag? Did you replace the belts yourself or did you buy the bike like this? Instead of meddling with baffles it might be cheap enough to get a used set on ebay.
Hi WeeWilly,
I was told the previous owner had put new ones on. I decided to check if they were properly installed. With the crankshaft at TDC, both pulleys were not aligned with the timing belt cover marks or "up" marks vertical. I slipped them off and re-installed them.
 

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Apparently some people are not very knowledgable about motorcycle tuning and do not know that exhaust modifications can make dramatic changes in air/fuel mixture.

If you would like an intelligent answer onwhy this occurs please email me at [email protected] or specifically request an answer here.

Vic
 

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i corrected my valve clearances, and went to set the (electronic) ignition advance, but my timing light wasn't working properly! arrgghh...Anyway, got it as close as i could, and synched the carbs. Sounds/rides better. Still looking for that correct advance timing to get the perfect acceleration curve. It's a lot better though. #1&3 carbs still have to have idle screw in quite far to get good idle, which leads me to a rebuild/cleaning later on.

Can one get pretty close with ignition timing by ear/test riding? The carbs synched very nicely.
 

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Goldwinger1984 wrote:
Apparently some people are not very knowledgable about motorcycle tuning and do not know that exhaust modifications can make dramatic changes in air/fuel mixture.

If you would like an intelligent answer on why this occurs please email me at [email protected] or specifically request an answer here.

Vic
Vic is referring to me but is being an insulting individual, which is normal for him. Vic, why not post your credible explanation here instead of taking traffic from the board? Id like to read it.

Heres the 411.

Exhaust back pressure controls (causes) something called "reversion" which is a reflow of exhausted combustion products back into the cylinder. This affects the apparent fuel charge in the cylinder, but cannot affect the A/F ratio from the fuel system, which is only controlled by airflow through the carb due to the "venturi effect." There is no connection between exhaust and carburetor except for gross airflow through the cylinders. If the carburetor is properly tuned and designed, and the increase in airflow is within the calibration of the carb, one will see little or no difference. Ive tested it.

The end effect to an untrained (non-engineer = Vic) mechanic is that it appears to have changed the AFR, but it has not. It has diluted the incoming AF charge with unburned/partially burned hydrocarbons and causes an apparent enrichment of the successive fuel charge.

The problem is in the definition of "A/F ratio." The AFR from the carburetor is one thing, the cumulative effect of unburned fuel (from a poor ignition as you will usually find on a Goldwing - but not after I tune them) is what appears in the cylinder and affects spark plug readings. When I tune an engine, there is no fuel left in the exhaust after the combustion stroke, so the exhaust has nothing to stuff back into the cylinder.

The mechanic usually has no means to check AFR and relies solely on spark plug coloration, which indicates cylinder conditions, not AFR.

If anyone would like some credible engineering references, Im a member of the Society of Automotive Engineers and can retrieve them from SAE's archives. Otherwise, continue with old wives tales from mechanics.

have a nice day, Vic.
 
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