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Old 07-10-2012, 08:25 AM   #16
photorider
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Almost sounds like one side is picking up before the other. Did you synch the cables just off idle?
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Old 07-13-2012, 01:17 PM   #17
2GbeemerLUV OP
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With the peace of mind provided from all y'all, I did my re-adjustments: valves were set too tight, statically retarded the points,**(disston: I couldn't believe it when it wouldn't start due to the points wire tangling around the atu, even with the cover on!!! Jinxed!!), then cleaned and balanced the carbs, end result: noise is gone (imagine that?)
Thanks everyone who contributed

Question in reference to above post: am I balancing the cables properly (sorry, another noob carb question)? Throw a leg over, with the bike shut off and my nose on the tank, I slowly roll the throttle and listen for the first of two clicks in the carb. I deduce the first one is the cable engaging with the needle and clip, and the second being the actual slide moving? Then I adjust until the first click on both sides are in unison and only one stereo click is heard.

My issue with some of the write ups I read that refer to 0.5 mm of slack in the cable, I'm not sure how to measure that. While its seated or while pulling on the cable? If pulling, when there's resistance, or when it's all the way open?

Ps, I'd love a link for those of you with carb-pull tunnel syndrome or carbthritis- but please, no snobum- I've read it and read it and right when it starts making sense I start to hallucinate
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Old 07-13-2012, 02:16 PM   #18
disston
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If you have ears that good you are way beyond me.

The carbs are balanced in two places, two times. One is idle. At idle there is no tension on the cables the butterfly or slide stops are at rest. The slack in the cables is measure at rest. 0.5 mm means small. About the thickness of 4 or 6 pages of note book paper. The amount of slack can be almost anything, the idea really is to make it as small as possible while still having a slack situation.

Just off idle is at about 1500 rpm and the carbs are balanced again.

One way to do this is you have the idle set and the carbs balanced at idle then watch the cable pull on both sides simultaneously. When you get the cables pulling together at exactly the same point they are balanced.

All of this is done with a manometer or the Harmonizer or shorting out the plugs.

When adjusting the carbs do not let the bike idle for too long. It can over heat. The bike must be warm when setting carbs but not over heated. I sometimes ride the bike till warm, about ten minutes, set carbs, ride some more, adjust some more, ride some more. Stopping usually in small shopping center parking lots. Or the 7-11 for a cup of coffee.
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Old 07-15-2012, 03:07 PM   #19
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Okay, I'm not too far off in terms of methodology- all that sounds familiar. I had it purring smoothly, but well into my ride today I was hearing the popcorn carb backfire- pulled the plug and it was carbon fouled. Coulda been thanks to the cool night air that I set them in vs the harsh summer mid day sun I was riding in. They're easy enough to clean, so in order place the burden of the malfunction on this bozo, I'll pull 'em tomorrow

I'm having trouble with: "..then watch the cable pull on both sides simultaneously..." the movement is all hidden in the sheath of the cable, I'm not sure what to watch for. Am I watching the cable or the carb?

Another method question: From what I can understand, the throttle stop screw (the bigger one), does not effect the gas/air mix-- is it acceptable to use it to set the off idle adjustment as long as I return it to proper idle speed?

Sorry if I'm ... As things are making more sense to me, I get more info out of articles/posts I've read before. But I've been lazy and slacking on my research. Looks like I got something to do at work tonight after all...
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Old 07-15-2012, 04:37 PM   #20
rufusswan
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Quote:
Originally Posted by 2GbeemerLUV View Post
-- is it acceptable to use it to set the off idle adjustment as long as I return it to proper idle speed?
NO, the "off idle" condition means the carbs are running on the cables and are NOT resting on the idle stops. The off idle synch is the 2nd synch function. When doing the idle synch, you must first be sure there is some slack in the cables so that you are sure the cables are NOT effecting rpm while you are setting the idle stops.

As to the first question above, don't over think it. You cannot watch both cables and both carbs at the same time. After you are done synching the bike at idle, adjust both cables so that they have about the same amount of slack. Then you can start the bike, set an off idle speed, say 1500-2000, and then synch using the cable adjusters.
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Old 07-15-2012, 06:28 PM   #21
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Aha. You put that in words even I can understand, I think.

I think I might loosen the cable adjuster lock nuts, turn the bike on and back out the threads until it increases rpm, then retighten by a half turn or so to give it slack. Fool proof? If nothing else, it will without a doubt prove I am in fact over thinking this.
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Old 07-15-2012, 06:53 PM   #22
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Yes, yes you are over thinking this

As the proud owner of a 74 R60 I spent most of last year huddled in a corner of my garage rocking back and forth wondering what all those strange noises were that occurred after I replaced the base gaskets. Get over it! These bikes are noisy, clunky, and cantankerous at times but they keep on ticking off miles. I think that noise that you are hearing (heard it on my own bike) is the fact that shifting at 3K is a bit early, Going from first to second I usually get the bike up to 4.5K and preload the shifter. This sounds like lugging to me and with slide non-diaphragm carbs seems the most likely culprit. Aside from that, ride the damn thing, it's more fun than a mental institution.
Forgot to mention yes set the carb pull as described, if the carbs are out of balance it will make all sorts of odd noises. I couldn't figure out why my bike was idling funny the other day, I looked down and saw my dog had grabbed one of the cables and yanked it out of alignment. I fixed it at a traffic light and the dog aint allowed in the garage no more!
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