1992 GSF400 Carb Conundrum

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lknbandit400
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Re: 1992 GSF400 Carb Conundrum

Post by lknbandit400 » Tue Jan 19, 2016 9:57 pm

LiteTekBlair wrote:Sounds like you are nearly there.
Yes, the pilot mixture screws are very sensitive. Try to set them individually by ear for the best result.

Have to separate carbs to fit fuel seals. It is not that bad if you are very methodical when you separate them, take photos, that sort of thing. Watch out for the springs that try to fly off into the void. Read my guide could be useful too.
http://www.litetek.co/Guide_MikuniBDST_Rebuild.html
Wow I didn't see that guide. Fantastic!

Also, I'm not familiar with how to set each carb individually by ear. I'm not sure what to listen for. I can google that, but in the meantime do you have some tips on that front?

Maelstrom
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Re: 1992 GSF400 Carb Conundrum

Post by Maelstrom » Wed Jan 20, 2016 12:13 am

I planned to write a guide for that and put it on my web page once I get my bike running but that will not be for some time, so I will just write it and post by the weekend
I had a quick google but most of what I could see was useless.
I have a links page that has a lot of useful stuff http://www.litetek.co/links.html and on most of the carb kit pages there are links to assembly guides. There is also a link to that rebuild guide on the home page.
Carb seal kits in viton & other parts
https://litetek.co

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Re: 1992 GSF400 Carb Conundrum

Post by Maelstrom » Wed Jan 20, 2016 4:53 am

Carb seal kits in viton & other parts
https://litetek.co

lknbandit400
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Re: 1992 GSF400 Carb Conundrum

Post by lknbandit400 » Wed Jan 20, 2016 5:15 pm

LiteTekBlair wrote:Here you go
http://www.litetek.co/Guide_FuelScrews.html
Thanks man! You reference a "fuel screw" or air screw. Is it safe to assume that if the screw is on the bottom of the carb, it's a fuel screw? For example, my CB175 has a additional screw on each carb (twin) next to the idle screw and I'm guessing it meters air since it's nowhere near the bowl....?

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Re: 1992 GSF400 Carb Conundrum

Post by Maelstrom » Thu Jan 21, 2016 1:14 am

No. Dellortos and Bings have their fuel screws in the body. The closest thing to a rule is to say if it is on the air cleaner side then it is an air screw.
Carb seal kits in viton & other parts
https://litetek.co

lknbandit400
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Re: 1992 GSF400 Carb Conundrum

Post by lknbandit400 » Thu Jan 21, 2016 1:36 am

LiteTekBlair wrote:No. Dellortos and Bings have their fuel screws in the body. The closest thing to a rule is to say if it is on the air cleaner side then it is an air screw.
Yeah I see the captions on the pictures you posted now. I missed that the first time around. Thanks man.

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Re: 1992 GSF400 Carb Conundrum

Post by lknbandit400 » Sat Jan 30, 2016 2:02 am

Well I still have a pilot/idle problem. I don't suppose it makes sense to adjust the air screws by ear without balancing the carbs with a gauge. I plan on buying the motion pro balancing gauge and knocking that out.

If I'm already at 3 turns out is there a likelihood that I need to go up to a 35 pilot jet instead of the 32? Could that be caused by me running a 1.5 air jet instead of a 1.45?

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Re: 1992 GSF400 Carb Conundrum

Post by lknbandit400 » Sun Jan 31, 2016 4:09 pm

I guess in all the hubbub I forgot that I have 1.5 air jets in instead of 1.45 because of the lack of availability of the 1.45. Since air is so much thinner than fuel, I'd suspect I'd need to go up in pilot anyway to maybe a 35 or higher, then bring the fuel screw in to maybe 2.5 turns out. All this of course after I get them balanced with a gauge. Does that sound about right?

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Re: 1992 GSF400 Carb Conundrum

Post by lknbandit400 » Thu Feb 18, 2016 6:43 pm

I haven't updated in a while. Two things I've done: 1) tried to get my gas tank situation sorted out and 2) try to sync the carb.

For the tank, I sanded off the resin compound on the bottom of my low mileage bandit. It's the only cosmetic thing wrong with the bike. Instead of spending $400 for fuel tank restoration, I bought the only bandit 400 tank on eBay in the US which turned out to be great on the inside and bottom.

I rinsed with metal rescue then baking soda rinse, and sent it off to my painter. Before it left, I also took the Dremel to the petcock hole because I've grown accustomed to the Pingel.

I'll put up a pic of the painted tank when it is done in a couple weeks.

Example of a few of the tens of holes on the old tank:

Image

Replacement tank:

Image

Widened petcock hole for the Pingel for the replacement tank:

Image

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1992 GSF400 Carb Conundrum

Post by lknbandit400 » Thu Feb 18, 2016 6:44 pm

I also got around to balancing the carbs last night. I was way off with the bench sync. But I was close enough to see my errors and correct them. I used a friends CarbTune. Worked like a charm. This is as close as I could get it:

[img]http://i904.photobucket.com/albums/ac25 ... wvxr8m.jpg[/img]

The rig:

[img]http://i904.photobucket.com/albums/ac25 ... e48bm3.jpg[/img]


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