Valve adjustment

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Garrett

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Hey guys my 1988 vmax has about 30,000 miles on it and there is some crackling and popping at idle and most days it will have alittle trouble idling for a long period of time, I’m thinking it’s time to get the valves checked but I’m to afraid to do it myself so I was wondering if anyone knew someone in or near Indiana that would do it for under $500?
 

Garrett

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Have you synched the carbs lately? I'd try that, first.
No I have not synced the carbs I know how to clean and rebuild carbs but I’m not sure if that’s what you mean by syncing them because I’ve never worked on something with 4 carbs like my vmax, thanks!
 

Parminio

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No I have not synced the carbs I know how to clean and rebuild carbs but I’m not sure if that’s what you mean by syncing them because I’ve never worked on something with 4 carbs like my vmax, thanks!
Get yourself one of these:

Carb Sync Set

Syncing the carbs is making sure that each carb is pulling its own weight when it comes to vacuum. There are lots of videos that show you how to do it. It typically takes about 15 to 20 minutes and is easy to do.

Basically you just pull the intake runner covers on either side. You'll see vacuum plugs on each intake runner. You pull those caps off, hook the hoses of the gauge set up to them, set the gauges up on top of the bike or hang them on the handle bars.

You'll need a flat head screwdriver.

Make sure the bike is warmed up to regular operating temperature. Up the idle a bit with the finger adjuster to about 1000 to 1100 rpm.

The order is:

Set 1 to 2
Set 3 to 4

Set right to left.

The "driver side" is 1 & 2, the "passenger side" is 3 & 4

When the bike is running, you open the valves on the bottom of the gauge set. You'll seet the vacuum gauge giving a reading. What I like to do is open the valve and then slowly close it down until the gauge is just BARELY bouncing. You don't want it to be completely still because if it is you may be choking the vacuum down and not get an accurate reading.

You'll be able to tell once you get them all open and set if you have a problem. You'll first adjust 2 to 1. Carb one cannot be moved at all. Once you get that matched you go to the other side and do the same.

On the "passenger side" you'll see two screws: one is to match carb 3 to carb 4 like you did on 1&2. The other is to match 3 & 4 over to 1 & 2.

Take your time and you'll figure it out. Once you've done it the first time it's easy to remember how to do. If you need help or support there's plenty of it to be found, but it's pretty elementary. You'll ace it.

Also important to note: each time you make an adjustment, give the throttle a blip or two and let it settle back down. That'll make sure you let the slop out of the linkage after the adjustment.

Get to it!
 

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