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Discussion Starter #1
:pepper: Ok,I put the carbs back in.Ouch! Anyway,I was so proud that I did it myself,as the Kaw dealer wanted $500.00 to do it.I found a ripped vac shutoff diaphram on the rear carb and also plugged jets.I cleaned everything and put it all back according to the book.:doh: I prayed,then started the bike.It started right up!:rockon: It sounded meatier, but off sync.I took it for a short ride and know that it needs to be sync'd.I adjusted to pilot screws to about 2 1/4 turns out.I am now trying to get the sync screw somewhere in the vicinity of correctness.If it's way out of sync,will it be hard to make it idle right?:baby: Am I close to adjusting the pilot screws right? By the way,the Kaw dealership here in Hutchinson,Kansas,wants $90.00 just to sync the carbs!:itchy-scr You guys and gals are the best,as you are owners and savy about our vn750's.Steve
 

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See crobins365's post on how she did hers. You will need to build or borrow a manometer. The cheap version is about $2 or so to build. That's how Cindy did hers. You can't sync the carbs by ear. The expensive route is to buy a manometer for min $50 or so. It's an easy procedure but you'll most likely end up shutting the bike down to adjust the sync screw as it's difficult to get to when the carbs are at idle.
 

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I'd say so, especially if it's badly out of sync. If it's close, you'd need a manometer to tell. Clogged pilot circuitry in the carbs will also cause rough idle, but since you had the carbs off, I'm sure you cleaned them up good.
 

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Hey mendez, you didn't by any chance take pictures did ya? I've been thinking about re-jetting myself....
 

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Mendez 90 bucks is a bit steep.. but the norm.. Up here in Olathe.. any dealer wants over $100. I borrowed a manometer mercury style from a friend of a friend for my kz1000 OMG it was like someone flipped a switch.. When they are in synch it just runs soooooo much better of course that is a 4 cylinder. For a two it should matter also.

too bad I didnt have a set for ya to borrow.. I am heading out west this weekend for opening weekend hunting.
 

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you can make your own manometer with tubing a meter stick and oil..
 

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When you're through, you can dump the stick and use the rest as an enema. Make sure the oil is mineral or canola oil, though!
 

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Hey, Mendez!

Here's a link on the web for a $1.55 carb sync tool - http://www.powerchutes.com/manometer.asp (sorry - it doesn't appear to be a hot link). Works like a charm. The gist of it is that you're using 12 feet of pvc tubing against a yard stick (6 extra feet allows for the connections to the carbs), and then using a light oil (I used final drive oil in mine - fill so that the top of the oil is around 26" on each side) as your "barometer." Pull the vac hoses off the carbs, hook the manometer tubes (one to each carb) and turn the engine on. A higher draw in one tube means that carb has a higher vacuum - the carb adjusting screw (down by the throttle cables) adjusts *only* the rear carb (your goal is to adjust the rear carb so the vac is equal to the front carb).

If you need more info on how to actually do the syncing, just holler. A few of us have blundered our way through the process (some with a vacuum pump, others (like moi) without), and it *really* makes a difference in the bike's performance.
 

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Discussion Starter #10
I made my own manometer and made it look really fancy.The problem that I encountered, was that one carb, I think the rear carb,tried to suck the oil out of the tube.I was lost then.
 

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where did you connect the front carb hose to? also make sure you get it adjusted at idle first then rev it a lil and adjust again.....
 

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Like Hizzo says - set your idle speed (if ya can - 1100ish) first. Just in case, the vacuum hoses go over those little brass "tubes" on each of the carbs. Sounds like you might be way out of sync - when i sync'd mine, the rear carb did the same thing and I shut it off and started adjusting. According to Clymer's, "Turning the butterfly bolt in will increase the vacuum in the rear cylinder carb...out will decrease." If your rear cyl was already pulling that hard, then lefty-loosey to decrease the vacuum so that it's closer to the front carb's pull. These are small adjustments - if you're not using an external fuel source (I didn't), you may have to reinstall the vac hoses on the carbs, start the bike up, get some fuel into the carbs, and then hook the manometer back up. A couple of times. But you;ll know when you're getting close - and once you're close, let the bike run as long as it can so that you can see that the adjustment has held and that it's right (once you're set, and the oil levels are almost equal, they'll pretty much stay put).
 

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Like Hizzo says - set your idle speed (if ya can - 1100ish) first. Just in case, the vacuum hoses go over those little brass "tubes" on each of the carbs. Sounds like you might be way out of sync - when i sync'd mine, the rear carb did the same thing and I shut it off and started adjusting. According to Clymer's, "Turning the butterfly bolt in will increase the vacuum in the rear cylinder carb...out will decrease." If your rear cyl was already pulling that hard, then lefty-loosey to decrease the vacuum so that it's closer to the front carb's pull. These are small adjustments - if you're not using an external fuel source (I didn't), you may have to reinstall the vac hoses on the carbs, start the bike up, get some fuel into the carbs, and then hook the manometer back up. A couple of times. But you;ll know when you're getting close - and once you're close, let the bike run as long as it can so that you can see that the adjustment has held and that it's right (once you're set, and the oil levels are almost equal, they'll pretty much stay put).
Like Cindy said, but if you tee into the left carb vacuum port (front carb) so that the vacuum line still goes to the petcock, it will run as normal and no need for external fuel source.

Jon
 

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Then They Are Way Out Of Sync. Try To Get Them Closer By Ear First Then Start Again
 
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