Rejet question

[Guest]

Hello.. I have a 78 gs750 cafe. It has air pods and 4 to 1 exhaust. I rebuilt the carbs and changed the jets with ones from the kit. The guy i got the bike from gave me the kit with the bike. a guy i know said that that kit has the stock size jets and i need to change them to run my current set up better.. Anyone know what size i need to go to? Any help would be greatly appreciated. Thanks

[stangas]

i too am interested in exactly this subject, so will be waiting patiently with you

[chef1366]

I would start by raising the jet needle two notches (putting the e-clip towards the tip two notches) and putting in a 117.5 main jets. May be a little rich but that's the way to start.
I'd also take out the air and fuel screws about a half a turn each the stock setting.

[Big T]

Hello.. I have a 78 gs750 cafe. It has air pods and 4 to 1 exhaust. I rebuilt the carbs and changed the jets with ones from the kit. The guy i got the bike from gave me the kit with the bike. a guy i know said that that kit has the stock size jets and i need to change them to run my current set up better.. Anyone know what size i need to go to? Any help would be greatly appreciated. Thanks

You don't know what size jet you put in?

What kit are you talking about?

[tkent02]

I haven't seen a jet kit for a VM 750 in decades.

[Steve]

I rebuilt the carbs and changed the jets with ones from the kit. The guy i got the bike from gave me the kit with the bike. a guy i know said that that kit has the stock size jets and i need to change them to run my current set up better..

First, we will have to know what "the kit" is.

If you are talking about those expensive, useless "rebuild kits", yes, they are pretending to be stock size jets, but there are no guarantees on how accurate they are.

Did you notice that those kits did not include all the o-rings that you needed to fully rebuild the carbs? You could have saved about $80 by getting the o-ring kit from cycleorings.com and using all your stock brass pieces.

Your main jets need to be increased a few sizes for the pipe and a few more for the pods. How many sizes will depend on whether you have good or cheap pods, as well as the quality and type of baffle in the pipe. Since we are not (yet) mind readers, we are not even going to guess and throw out some numbers.

.

[ATNasty]

You don't know what size jet you put in?

What kit are you talking about?

I dont know.. The bike wouldnt start when i got it.. I cleaned and rebuilt the carb with the kit that the guy had. I got it running but not well.. I dont have a clue what kind it is.. But i showed my friend the remander of the kit and he knew what it was and said the kit has stock size jets. I quess a better question is what are the proper jets to use with air pods and 4to1 exhaust? And how can i get this bike running proper?

[ATNasty]

First, we will have to know what "the kit" is.

If you are talking about those expensive, useless "rebuild kits", yes, they are pretending to be stock size jets, but there are no guarantees on how accurate they are.

Did you notice that those kits did not include all the o-rings that you needed to fully rebuild the carbs? You could have saved about $80 by getting the o-ring kit from cycleorings.com and using all your stock brass pieces.

Your main jets need to be increased a few sizes for the pipe and a few more for the pods. How many sizes will depend on whether you have good or cheap pods, as well as the quality and type of baffle in the pipe. Since we are not (yet) mind readers, we are not even going to guess and throw out some numbers.

.

I didnt spend any money on the kits.. The guy that i got the bike from just had them.he didnt even know what it was.. They came in little ziplock like bags. I do remember the they didnt have all the rubber pieces needed.
The air pods that came on the bike im pretty sure are Mikuni they are chrome looking with wire mesh.

[tkent02]

No those are the Emgo Dirt Sifters. They filter nothing, flow no air, and are untunable.

[ATNasty]

No those are the Emgo Dirt Sifters. They filter nothing, flow no air, and are untunable.

Really? Could you point me in the right direction of some good filters please?

[tkent02]

K&N or APE are very good.

[Steve]

I cleaned and rebuilt the carb with the kit that the guy had.

How did you "clean" the carb? If you just unloaded a can of spray in its general direction, you still need to CLEAN the carbs. (click the link)

I quess a better question is what are the proper jets to use with air pods and 4to1 exhaust?

Did you happen to see my post directly over yours?
It was almost two hours earlier, so you probably refreshed the screen.
Here is the part that answers that question:

Your main jets need to be increased a few sizes for the pipe and a few more for the pods. How many sizes will depend on whether you have good or cheap pods, as well as the quality and type of baffle in the pipe. Since we are not (yet) mind readers, we are not even going to guess and throw out some numbers.

And how can i get this bike running proper?

You are new, so you probably haven't introduced yourself in the GS Owners section. (I just looked back through your 5-post history and see that, indeed, you haven't.) When you do a proper introduction, our resident greeter (and all-around great guy) will give you his MegaWelcome, which gives links to all the information that you will need. It's not a quick process that will have you running by this evening, so sit down, have a read and get ready to get your fingernails dirty.

In the meantime, be sure to also look at the Top 10 Newbie Mistakes to make sure you don't do any more of them. (click the link)
So far, there is only evidence of commiting the first six errors (#1 has two parts) and possibly the last two.

.

[Big T]

I quess a better question is what are the proper jets to use with air pods and 4to1 exhaust?


And how can i get this bike running proper?

There is no single setting that works for all bikes - there are many factors that make every bike different

So, you have to start somewhere and tune to your factors -which exhaust, pods, compression, altitude, etc, etc,etc

BTW, did yoy save the brass parts you took out? If so, look closely for a number and a double box symbol

Proper - check the megawelcome, especially the newbie mistakes
You're getting ahead of yourself, you have a lot of work to do first

[ATNasty]

How did you "clean" the carb? If you just unloaded a can of spray in its general direction, you still need to CLEAN the carbs. (click the link)



Did you happen to see my post directly over yours?
It was almost two hours earlier, so you probably refreshed the screen.
Here is the part that answers that question:




You are new, so you probably haven't introduced yourself in the GS Owners section. (I just looked back through your 5-post history and see that, indeed, you haven't.) When you do a proper introduction, our resident greeter (and all-around great guy) will give you his MegaWelcome, which gives links to all the information that you will need. It's not a quick process that will have you running by this evening, so sit down, have a read and get ready to get your fingernails dirty.

In the meantime, be sure to also look at the Top 10 Newbie Mistakes to make sure you don't do any more of them. (click the link)
So far, there is only evidence of commiting the first six errors (#1 has two parts) and possibly the last two.

.

Hahaha.. Thanks i just introduced myself in the owners thread. Lots of knowledge on this forum.. Im guilty of 1a,2,3 and 4.. kind of .. I got the bike the way it is. I do want to learn the bike. so I will be reading a whole lot. thanks