The Good Humor GS850G

[Nessism]

You might want to check my signature for the carb rebuild tutorial and Newbie Mistakes thread. Both will help guide you towards a successful rebuild.
BTW, I have O-ring kits..

[Buffalo]

You might want to check my signature for the carb rebuild tutorial and Newbie Mistakes thread. Both will help guide you towards a successful rebuild.
BTW, I have O-ring kits..

I have been following your tutorial! It's been super helpful! Thanks for the offer of the o-rings, so far, I've had what I needed in my o-ring kit, but if I run into one I can't find, I'll let you know!

[Who Dat?]

What "o-ring kit" do you have? You should know that some of the o-rings in the carbs are made of different materials, and it's good to have the right stuff.

[Buffalo]

What "o-ring kit" do you have? You should know that some of the o-rings in the carbs are made of different materials, and it's good to have the right stuff.

I have an o-ring assortment for fuel applications from my clip supplier, disco automotive. I've been working on vehicles for over 20 years and am very much aware that not all materials are compatible with fuel.

[eil]

Man, I am digging this. Haven't seen such a thorough restoration thread in a long time.

Some advice if you haven't read it yet: it's very critical that the rubber boots between the carbs and head are air-tight, and old ones tend to leak where the metal and rubber are bonded. Strongly consider replacing those as well as the o-rings underneath. Even if yours are not leaking now, they probably will soon. They are not cheap, unfortunately.

[nvr2old]

Fun thread. Lots of great pictures. On your question on whether to paint the engine silver or black, I would keep the engine stock looking. Polished covers and silver painted motor. It would match the silver in your paint job nicely. Looking forward to the rest of your build.

[Buffalo]

Man, I am digging this. Haven't seen such a thorough restoration thread in a long time.

Some advice if you haven't read it yet: it's very critical that the rubber boots between the carbs and head are air-tight, and old ones tend to leak where the metal and rubber are bonded. Strongly consider replacing those as well as the o-rings underneath. Even if yours are not leaking now, they probably will soon. They are not cheap, unfortunately.

I do have new o-rings for the intake boots, I'm not 100% sure how pliable the boots are supposed to be, they don't seem to be too hard... that being said, I may see go ahead and source new ones form Suzuki while I've got it apart!

[Buffalo]

Fun thread. Lots of great pictures. On your question on whether to paint the engine silver or black, I would keep the engine stock looking. Polished covers and silver painted motor. It would match the silver in your paint job nicely. Looking forward to the rest of your build.

I didn't think of painting the engine to match the silver on the tank! Thanks for the suggestion! I will definitely be polishing the covers!

[Nessism]

I do have new o-rings for the intake boots, I'm not 100% sure how pliable the boots are supposed to be, they don't seem to be too hard... that being said, I may see go ahead and source new ones form Suzuki while I've got it apart!

Good idea. The O-rings must be Viton. Buna-N won't last.

[Buffalo]

Good idea. The O-rings must be Viton. Buna-N won't last.

That's what I've got, a viton kit from disco automotive, they are the company that I source all my aftermarket body panel clips, rivets, bolts and screws from. I've made the mistake of using Buna or plain rubber o-rings in the past, and it makes an unholy mess. Even the buna ones, though fuel resistant get really brittle, really quickly. With the switch from r134a to r1234yf in cars, we have had to switch to all viton o-rings, as the pag oil for 1234yf will eat the buna o-rings. r1234yf is $19 an ounce, and most cars take a little over a pound of refrigerant, so the last thing I want to do is throw a couple hundred bucks out the window because of cheap o-rings. Now the intake boot o-rings I sourced were direct from Suzuki, so I am not worried about them.

Have you had an experience with the aftermarket intake boots? They seem too cheap to be quality, being that a set of 4 aftermarket boots is the same price as a single OE boot. I am very much a buy once, cry once guy, so I don't mind spending the money on OE. The other ones I saw were a machined aluminum flange that then had a rubber tube that attached to them, I was curious if anyone has any experience with those.

[Nessism]

Buna-N O-rings in the carbs are fine, if not preferable. It's the intake boot O-rings that must be Viton. Regarding carb O-rings, the sizes you need are in the carb rebuild tutorial. One correction, though, don't use the smaller 1mm x 2.5mm O-rings for the pilot screws, use the thicker/larger 1.15 x 2.7mm size.

[Buffalo]

Here are some update pics! Finished cleaning and rebuilding the carbs today. They were really, really nasty, but that's to be expected when they had been setting for a decade, not being properly drained and stored...


The ultrasonic cleaner worked amazing for these carbs

I don't have new boots yet, but I did replace the o-rings on the old boots, they were incredibly brittle:


The airbox is apart, and got a soapy bath while I was washing a car this morning, when I get a minute today or tomorrow, the box is going to get a fresh coat of paint, the side covers polished and new foam weatherstripping all around:


Carbs back together, bench syncronized. Waiting on my gauges so I can sync tune them on the bike, those should be here tomorrow:

And I couldn't resist throwing the carbs back on the bike and seeing if it would fire up, guess what? It did!

https://imgur.com/qGn1TW3 (video of it running)

I know it is running a really high idle right now with the airbox off, but I was really happy that it fired up and ran after setting for so long. I was able to engage the transmission through all five gears as well, so at least I now know the clutch packs aren't stuck together. Next up will be to get the battery tray sorted out, the lithium battery that I have for it is just a touch too large, so I am either going to 3d print a new battery tray or I may just cut the old tray and add a bit of material to make it larger. Then I've got new dyna coils and wires, a dyna s ignition system (from a fellow member here), rebuild the forks, change the oil, new tires (maybe paint the rims, haven't decided yet) and then get it all together for a test ride!

[2BRacing]

Well done on getting the carbs so clean! What cleaning solution did you use in the ultrasonic cleaner?

[Buffalo]

Well done on getting the carbs so clean! What cleaning solution did you use in the ultrasonic cleaner?

Believe it or not, Zep All Purpose Pine Cleaner and hot water. Each carb took about 90 minutes to clean in the ultrasonic cleaner. I did it in 30 minute intervals. The first 30 minutes were the carbs as stripped down as I could get them, but there were some components that were just glued it with old gas varnish and I couldn't get out until they had been loosened up with the ultrasonic cleaner. It was mainly the float needle seats but on one carb, the needle jet was so gunked up that it wouldn't come out, even with trying to tap it out with a wooden dowel.

Overall, I think the ultrasonic cleaner did a better job cleaning the carbs than chemical carb cleaners do. I rebuilt the carb for my 1967 Ford 4000 tractor last winter and used this same method, even my dad, who runs the service department at our local John Deere dealer and who has been fixing tractors for 49 years commented on how much cleaner that carb was compared to the ones that they have done with solvent.

[salty_monk]

Morgan Carbtune is the king of the carb syncing tools..... https://www.carbtune.com/ you can get them next day on Amazon these days. Gauges are ok but it's a lot of extra messing around as you have to zero each gauge to the cylinder to do it properly.