Initial tuning question 79gs1000

[Guest]

Hey everyone, first time posting here as this is my first GS. That being said I have had my fair share of KZ's and CB's. Picked up a bike on the cheap but the previous ok is owner really let the poor girl go. Did some general maintenance to the carbs like a cleaning and adjusted float heights but was not sure where to start with the air and fuel screws as they had for sure been tampered with. So before I get out my old syncing tool and get too deep just wanted to know if anyone knew the best starting point. I'm usually a 1 1/2 turns out kinda guy but figured I would defer to the experts. Ry je bike is 100% stock, no pods, no fancy exhaust. Any help would be appreciated.

[Big T]

Slide carbs? Fuel screw -3/4 turn
Air screw - 1 1/2 turn

Then tune air screw for high idle

[Downeydyer]

Vm carbs not Cv

[Big T]

Yeah- VM carbs = slide

CVs lack a fuel screw

[Downeydyer]

Well it turns out the guy I got the bike from snapped one of the fuel mixture tips into the carb base. Tried lots of compressed air and penetrating oil to get it out but no luck. Any ideas guys? The bike did run with initial tuning but not well so I took it apart again to find this problem. Pretty discouraged, would rather not make this a parts bike but not spending hundreds on a second hand set of carbs either.

[Steve]

I have found that a broken tip usually has the point just barely sticking into the throat.
Roll the side of a Phillips screwdriver over it, it might pop out.

Replacement screws are available for considerably less than "hundreds". :encouragment:

.

[leftlostcommonsense]

If you can't get it out check ebay I see a whole rack of VM carbs for $112. I'm not sure which ones you need but if that's not something you're willing to spend you may as well go ahead and get rid of the bike because you're going to be looking at a good grand to get the bike safe and reliable. You may not think so (I didn't either) but you will spend that much unless you don't value having a safe bike that will get you home...I remember arguing there's no way I could put a grand into a running bike when I got mine but I did end up spending that much and there wasn't anything wrong other than damage caused by sitting for a few years. Over time you continue to find things that need to be addressed and that cost money. It's just the name of the game is all..

[alke46]

If you can't get it out check ebay I see a whole rack of VM carbs for $112. I'm not sure which ones you need but if that's not something you're willing to spend you may as well go ahead and get rid of the bike because you're going to be looking at a good grand to get the bike safe and reliable. You may not think so (I didn't either) but you will spend that much unless you don't value having a safe bike that will get you home...I remember arguing there's no way I could put a grand into a running bike when I got mine but I did end up spending that much and there wasn't anything wrong other than damage caused by sitting for a few years. Over time you continue to find things that need to be addressed and that cost money. It's just the name of the game is all..

Very true indeed. After all this new to you bike is 40 years old and has probably been neglected most of it's life. You have to decide just how much you are willing to spend. If not upwards of a grand, then go ahead with the divorce.

[Downeydyer]

Ow I 100% hear you on spending the safety and maintenance stuff just a little hard to stomach a few hundred on a set of carbs. I am going to keep plugging along at trying to get that tip out. If I can't I will try and tune around it and wait for a cheap set of carbs that need a rebuild to pop up locally. I appreciate the I put guys.

[Big T]

If the tip doesn't come out, you should be able to get a carb body from someone here.

But, I want to know how you cleaned the carbs without removing the fuel screws.

[Downeydyer]

The fuel screws did not need to come out to take the bowls off. So I had left those and the air screws alone and did my usual carb cleaner and compressed air in all the orifices, adjusted the floats, then threw them on. Went to adjust the fuel screws because it wasn't running right and realized one was way off. The one with the snapped off tip.

[alke46]

So what you are saying is that the carbs have not been properly stripped and dipped. That needs to happen. And, this usually happens right after you have checked the valve clearances.

[Steve]

And, there is no way to "tune around" a blocked pilot port. Anything you try to do will simply not get the job done.

As far as your carb "cleaning", you didn't even get a good start at it. The carbs need to be THOROUGHLY taken apart (that includes the pilot screws removed, along with the "choke" plungers and EVERYTHING else), soaked overnight in carb cleaner dip, THEN have some carb cleaner spray spritzed through the orifices and blown out with compressed air. Until you do that, the carbs are simply not worth of being called "clean". Then, when you go to put them back together, do NOT waste any money on carb reubild kits. All you will need (except that damaged screw) is an o-ring kit from cycleorings.com, which costs about half of one carb kit (you would have needed four).

You will, of course, need to sync the carbs, but you said you have a tool for that. Just out of curiosity, which tool do you have?

.

[Downeydyer]

It's an older tool I got from z1. Has the 4 vacuum gauges and adapters and fittings to sync them. I understand there is far more in depth carb cleanings I wanted to just fire the engine to make sure it was a runner. That being said if I can't get that tip out of the carb body I wont dive deeper into the cleaning. On a plus note it did run haha.

[hannibal]

I recommend soaking in the carb dip longer than 24 hrs. I had to reclean my carbs because I did not get all the debris out. I say 48 hrs in the carb dip. It did discolor my carbs, but appearance is the last thing on my list.

You can find a carb cleaning tutorial plus a whole lot more here: http://members.dslextreme.com/users/bikecliff/