Engine Stops While on Idling Rev

[Rich82GS750TZ]

@Rich82GS750TZ - if we are using pods for air intake instead of an airbox (because the previous owner didn't left an airbox on the bike but instead a pods on it), does that mean we have to rejet the carbs?

Yes. That’s as good an answer as I can give. I’ll bet there are hundreds of threads on the forum about rejetting for pods. You’ll see recommendations in those threads or from others chiming in here with experience. I have none. Depends on if you have VM or CV type carbs, and what kind of pods. All pods are not created equal. Cheap ones provide nearly no restriction and may actually block important ports on the intake side of the carbs. Again, others with experience will have to advise you on specific jetting with specific pods, on specific carbs. No easy answer here.

Big tip on using the site’s search function:
always used Advanced.
always be specific with your search words
always search titles only. If you don’t, you won’t get good search results at all.

[allojohn]

@allojohn If our carbs have pods rather than airbox, how do I know which jet I should change to adjust the amount of fuel (like do I go up one size or go down one size)?

You need to do a lot of reading on the forum and the workshop manual which is available on the BassCliff site you've already been directed to.
The carb cleaning pdf has images of the carbs broken down to their components - study it.
Also, see my sig.... I have a '78 750 with pods. I, and a bunch of others on here have done the donkey work for you already. A bleeder jet (pilot) of 15 (stock) and 117.5 main jet will work - full stop. BTW, you have four carbs so you need four main jets.....

Now, as some others have said there's probably many other things you need to fix on this bike to make it safe, reliable and smooth running. Learn about your bike and figure out what's important and what ain't. Very few people buy a 42 year old bike and not have to spend dozens of hours and lot of $$$$ making it road worthy.

[schwalbewurger]

Yes. That’s as good an answer as I can give. I’ll bet there are hundreds of threads on the forum about rejetting for pods. You’ll see recommendations in those threads or from others chiming in here with experience. I have none. Depends on if you have VM or CV type carbs, and what kind of pods. All pods are not created equal. Cheap ones provide nearly no restriction and may actually block important ports on the intake side of the carbs. Again, others with experience will have to advise you on specific jetting with specific pods, on specific carbs. No easy answer here.

Big tip on using the site’s search function:
always used Advanced.
always be specific with your search words
always search titles only. If you don’t, you won’t get good search results at all.

Will do! Thank you for your the info and advice in the search function.

[schwalbewurger]

You need to do a lot of reading on the forum and the workshop manual which is available on the BassCliff site you've already been directed to.
The carb cleaning pdf has images of the carbs broken down to their components - study it.
Also, see my sig.... I have a '78 750 with pods. I, and a bunch of others on here have done the donkey work for you already. A bleeder jet (pilot) of 15 (stock) and 117.5 main jet will work - full stop. BTW, you have four carbs so you need four main jets.....

Now, as some others have said there's probably many other things you need to fix on this bike to make it safe, reliable and smooth running. Learn about your bike and figure out what's important and what ain't. Very few people buy a 42 year old bike and not have to spend dozens of hours and lot of $$$$ making it road worthy.

For sure! Thank you for your info and experience. Will definitely follow your advice. Also will update with more pictures of the bike.

[schwalbewurger]

Carbs of the bike with pods
Carbs.jpg

[schwalbewurger]

Part of the exhaust
IMG_3463.jpg

[schwalbewurger]

Full picture of the bike (still have some saran wrap on it while prepping for fiberglass work to create new seat...). This was about 3 weeks ago.

GS750 Incomplete.jpg

[Rich82GS750TZ]

Part of the exhaust
[ATTACH=CONFIG]61282[/ATTACH]

Well this ought to be good. Please tell me that the PO (previous owner) didn’t tell you that those are exhaust pipes.

Those are engine case guards. Have nothing to do with exhaust. I’m really afraid of where this is leading.

[allojohn]

Well this aught to be good. Please tell me that the PO (previous owner) didn’t tell you that those are exhaust pipes.

Those are engine case guards. Have nothing to do with exhaust. I’m really afraid of where this is leading.

Oh boy......

[Big T]

Part of the exhaust
[ATTACH=CONFIG]61282[/ATTACH]

You are kidding, right?

Time to stop trying to be a "builder" and start trying to be a mechanic

[roeme]

You are kidding, right?

Time to stop trying to be a "builder" and start trying to be a mechanic

Take it easy, obviously they're new to this and those bikes, and can't identify parts yet. They don't seem ignorant and willing to learn.

We shall see where this goes.

(P.S. I do admit to snickering a bit when I saw the "exhaust parts")

[Steve]

My condolences on the "pods".

Partly because you are about to head on a frustrating journey in the world of jetting, but also because those are the cheap $25 Chinese specials that are rather hard to tune the carbs for.

Sorry to be rather blunt about it, but I'm actually serious about it. The jetting required depends on air flow. Unfortunately, the air flow available with those pods will change with the daily humidity. The paper will absorb some of the moisture in the air, and the slightly-moist filter will partially restrict air flow. If you really want the "look" of pods for your "cafe racer" project, good pods will cost considerably more. K&N pods are well over $100. APE pods are just as good, virtually identical to K&N, but cost considerably less. Your best bet would be a stock airbox, but that might not fit with the "look" you want.

.

[schwalbewurger]

Hello everyone,

My bad - I didn't know that those were the engine case guards. Thank you for teaching us more info! We are about to buy parts and tools needed to rebuild and clean the carbs - will post pictures of it. Will take no shortcuts to it.

[schwalbewurger]

So I've searched through the forums through the advanced search, and then using the "search titles only" function for GS750 pods tuning/GS750 pods adjustment. Please correct me for my mistakes, but here is what I've gathered:

-Jet needle (not needle jet) needs to be adjusted at least one notch up.
-Main jet: 117.5 (bought and arrived just now)
-Pilot Jet: Stock (15) (bought and arrived just now)
-Fuel screw: at least 7/8 out (because 7/8 out is stock airbox) - how many turns out should it be for our situation?
-Air screw: At least more than 1 1/4 turn back (since stock airbox is 1 1/4 turn) - how many turns according to y'all's experience does the air screw need to be for K&N pod filters with 117.5 main jet and 15 pilot jet? I found on the forum search that people are getting at about 1.5 turns out.

Also to recap, we are planning to use either K&N pods or APE pods (though I cannot find APE pods for 1978 GS750, they only have pods for 1980+ GS750) and stock exhaust pipes. Elevation is about 2300 feet here at Lookout Mountain. And I'm sorry for the noob question, but the pilot jet and the main jet just needs to be screwed tightly right?

We have been able to clean up the carbs and rebuild it, so now we just need to put the appropriate main and pilot jets and tune it up. Turns out when we cleaned the carbs, on carb #1, the pilot jet was broken - the top piece was stuck on the carb body, but we were able to pull it out and replace it with a new one (15).

Thank you very much

[schwalbewurger]

Pilot jet from carb #1
IMG_3251.jpg