Carb help please

[Boriqua]

I found the article by Kool aid kid to be very useful in helping me understand and finally get my bike to a sweet spot. I had read dozens of posts on several forums but the by ear method wasnt working for me. I just dont have enough experience. When I realized how rich or lean was affecting the idle and knowing I buttoned everything else up .. Took a couple of tries but my bike runs great.

http://www.thegsresources.com/_forum/showthread.php?199096-Adjusting-the-Idle-Mixture-on-CV-Carbs

[Nessism]

There are a few here with '78 750's with K&N pods. I run stock pilot 15 and main jet at 117.5, e-clip at position 4.
Fuel screw 1 full turn out, air at 1.5 ish, with highest idle. Syncing the carbs will make a huge difference so after you've adjusted the valves borrow a Morgan Carbtune and git er done!

What kind of exhaust? Same question for OP? I was assuming stock but it's not good to assume...

[BurtyMcSquirt]

Thanks for all the great info. Keep it coming

[Nessism]

Thanks for all the great info. Keep it coming

You didn't answer. What exhaust system?

[allojohn]

What kind of exhaust? Same question for OP? I was assuming stock but it's not good to assume...

I've run stock, V&H and currently Delkevic with this setup. If the exhaust makes a difference it doesn't appear to be significant..... to me.

[alke46]

I found the article by Kool aid kid to be very useful in helping me understand and finally get my bike to a sweet spot. I had read dozens of posts on several forums but the by ear method wasnt working for me. I just dont have enough experience. When I realized how rich or lean was affecting the idle and knowing I buttoned everything else up .. Took a couple of tries but my bike runs great.

http://www.thegsresources.com/_forum...re-on-CV-Carbs

I have not read this thread but the OP is working with vm carbs. At least that's what I suspect since his bike is a 78 750. This thread is about the cv carbs. I don't know if it matters or not, just throwing it out there.

[BurtyMcSquirt]

stock exhaust 4 to 1

[Boriqua]

I have not read this thread but the OP is working with vm carbs. At least that's what I suspect since his bike is a 78 750. This thread is about the cv carbs. I don't know if it matters or not, just throwing it out there.

It wasn't so much the physical manipulation of screws that helped me solve my issues but the part in the article where he describes symptoms and causes. I had a high idle and I kept being told it was an air leak when I had gone through the bike 100 times and it was sealed tight. I did at one point have my uno filter dry out which caused me to lean out but when I went to paper things got a bit easier.

After reading the article I started tuning based on what the bike was doing when warm. At first hanging idle so if all else was good I just had it set up to lean. So went up half a turn and it would slowly die at lights. Too rich. Turn down 1/4 and it would idle. So it was that diagnostic that helped me get there. so while the carbs may be different that little bit of information was immensely helpful to this newbe who had struggled and basked in profanity for weeks.

I've since checked the plugs and they look great but it was really that little bit of info that drove it home for me.

For months I was afraid to go to far from home but I have since put several hundred miles on her and she runs great.

[alke46]

Yeah once you get a little bit of confidence in them, they will take you almost anywhere without issue. This is particularly true after you've got the electricals taken care of.

[BurtyMcSquirt]

I found the article by Kool aid kid to be very useful in helping me understand and finally get my bike to a sweet spot. I had read dozens of posts on several forums but the by ear method wasnt working for me. I just dont have enough experience. When I realized how rich or lean was affecting the idle and knowing I buttoned everything else up .. Took a couple of tries but my bike runs great.

http://www.thegsresources.com/_forum...re-on-CV-Carbs

This was a really informative article. Great post.

[BurtyMcSquirt]

I thought I'd shoot you guys a pic of my plugs. Looks rich.20171028_123422.jpg

[Steve]

stock exhaust 4 to 1

So which do you have, stock or 4 to 1?

No GS left the factory with a 4 into 1 exhaust system.

.

[BurtyMcSquirt]

So which do you have, stock or 4 to 1?

No GS left the factory with a 4 into 1 exhaust system.

.

Oh. Well in that case I have no clue. It has no markings on it but I do know it will need to be replaced, its fairly well beat up and all rust.

[BurtyMcSquirt]

If your valves are tight (the usual situation), the intake valve closes while the piston is coming up, which lets some air out. The only place for it to go is back through the carb. It picks up a bit more fuel, because the carbs don't really care which way the air flows through, they are going to add fuel. On that cylinder's next intake cycle, the valve opens, the piston goes down and, you guessed it, you get a THIRD dose of fuel in the mixture.


.

So 6 out of 8 valves weren't measurable with my set of gauges (go down to .03mm) and at the .03mm feeler it wasn't even close to making it through. Currently recording shim settings to purchase the ones i need to adjust.

[Steve]

Have you looked into the GS Shim Club? A simple exchange and a token gratuity, you don't have to purchase shims.

Unless you want to start your own collection, that is.

.