New to a GS- carb cleaning Q

[dkruitz]

Hi All:
I've just picked up an 82 GS450GA (shaft drive semi-automatic) to help get my brother-in-law back on his feet for basic transportation. We cleaned the carbs yesterday and got them back on the bike, but it's still very difficult to start and we have to use starter fluid which only lasts briefly. I've previously rebuilt the 4 on my '71 CB500 and it worked out better than these two, and they were in much worse shape than the ones from the Suzuki.

Now, we might be doing something very wrong, let me fill you in. We have the tank off, and used an oil can to put in about two cans full of gas into the carbs. The airbox is disconnected to enable easier carb insertion/removal.
When redoing the carbs, there were brass two screws in each that we couldn't get out and were concerned about stripping the threads. The first was the small one at the face of the throat opening, the other next to the highspeed jet. Could these be the problems? We soaked the carbs in solution and used plenty of spray cleaner too. But those two didn't wan to budge. Should we just soak 'em longer, or can we stick a wire in there to verify passages are clear? We did get the main jet out and it's good.

At rest how high should the barrels be - how much gap to the bottom of the throat?

[Steve]

First of all, let me welcome you to the forum. BassCliff will be along shortly with the "official" welcome.

Sounds like you have gotten a start in to the ritual of getting a bike going. There is a pretty good write-up in the Garage section about cleaning the carbs. Along with a full cleaning, it makes sense to also replace the o-rings in the carbs and also the ones between the intake tubes and the cylinder head. The best method is to completely disassemble the carbs and soak all the mettalic parts overnight in Berryman's dip, one carb at a time (don't mix parts between carbs).

How far should the slides be up in the barrels? Never really measured them, but probably about 1/4" or so with the engine not running.

The brass jets in the intake throat (about the 8 o'clock position) are air jets. It is best to remove them for cleaning, but it won't hurt anything if they stay in while being dipped. Not sure about the other one, what are you calling "the highspeed jet"?

To enhance longer life of your bike and the safety of those around it, keep the starter fluid on the shelf, do not use it to start the bike. It is too easy to get carried away with its use, and the results are usually less than pleasant.

Another thing that will be necessary to ensure proper operaion of your bike is valve adjustment. This should really be done before adjusting the carbs. You can clean the carbs and change the o-rings any time, but it's best to adjust them with the bike running, which will be after the valve adjustment.

Here are some links to different areas in the garage and suppliers that can help get your bike running:
Valve adjustment
Carb cleaning
O-rings for carbs and intake boots

Enjoy working on the bike, and remember that we want pictures, especially of your rather rare bike. 8-[


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[dkruitz]

Thanks for the article links, that should help. I think I'm going to resoak the carbs in a new can of carb solution. Is a backfire a symptom of needing a valve job? The bike has 11,500 miles on it and is suffering more from sitting than anything else.

Also, I just reread the carb cleaning instructions and found two discrepancies with my job yesterday, I did not see the air screws, and those must be under a plug. And, I did not see a plug for the pilot screw - is that needed?

Here's the barn fresh photos of my brother-in-law's 450 in question, and after the first cleaning.

http://www.elginoutboard.com/jonsbike/

Here's a picture of my '71 CB500 (after first cleaning and right after we moved it, hence all the boxes :-)

http://www.elginoutboard.com/cb500-2.jpg

[spyug]

Carb cleaning can be a big pain in the you know where. All bikes that sit for any length of time without stabalized gas will have gunge in the fuel system from the tank to the carbs so all will need cleaning.

The carbs themselves can be the hardest to sort out and often you will need to clean them several tmes before they work right. As mentioned, you should dip each carb seperately. Disassemble everything but be sure not to dip any rubber o-rings or the diaphrams...they will dissolve.

You mention that you are trying to start and run with the airbox off. This might be a problem. I find that while i can do this with my 2 carb Yammie XS, the 750 4 carb GS will not run with the box off. It might be the same for you.

Read the carb cleaning tutorial over a few times and be sure all passages and jet orifices are clean. When working with the jets try and not enlarge any of the holes or that will make things even worse.

Also ,as mentioned, don't use starter fluid as you can blow the head off the bike and or do yourself an injury and be sure to look at the valve clearances as incorrectly set valves will make it near impossible to start.

Electrics are also extremely imortant for easy starting so make sure your battery is good, your terminals and connectors are clean and you have good plugs. Actually drop in new plugs as they are cheap enough.

Good luck with the new project and welcome aboard.

Let us know how you make out.

Cheers,
Spyug.