How to jet for pods and open exhaust
When you switch to high flow air filter and open exhaust, the engine absorbs more air than before. However the carburetors will not deliver the corresponding amount of fuel if we do not rejet them. Therefore, we have to follow up with a correction of the jetting. How much is difficult to say. Sometimes it is enough to increase the main jet circuit with a 20% larger jets (i.e. from 100 to 120). In other cases, you may need to go even bigger. I advice you to start with one size bigger main jet than you suspect will be needed and work your way down from there.
As for the idle circuit, it is usually enough by increasing it just one or two sizes (i.e. from 40 to 42 or 45). This applies in most cases.
Do not expect Braigasen to come up with suggestions on how to jet your specific carburetor. All bikes are unique and there are no short cuts - it is always a matter of trial and error! I have worked on cv-carburetors that needed as much as 60% larger main jets before we were finished.
Exhaust bangs on engine breaking?
If you let go the throttle and experience bangs in the exhaust - and you know with yourself that there are no air leaks - then try with opening the Idle Mixture Screws a tad further.
Hesitation and jerking when going from half to full throttle?
Try a larger main jet and see if the problem disappears. *
It feels sluggish at full throttle?
If you cannot feel any major change in speed when going from 3/4 to full throttle, then the main jet is probably too big.
If it does not respond willingly up to half gas?
Try shimming the needle. A 0.5mm shim is often enough.
Air filter location?
When mounting pods directly onto cv-carburetors turbulence often occurs, especially in the sensitive part of the carburetor where we find the venturi and the vacuum slides. For this reason, it is recommended to mount the filters on extension pipes, approx. 70mm long. This will calm down the air flow and make the carburetors easier to jet.
* If you find the changing of jets laborious... then you can take the shortcut and cover the filters. If it runs better with air restriction, then you must increase the main jet size. If it runs worse, then decrease it.
When you switch to high flow air filter and open exhaust, the engine absorbs more air than before. However the carburetors will not deliver the corresponding amount of fuel if we do not rejet them. Therefore, we have to follow up with a correction of the jetting. How much is difficult to say. Sometimes it is enough to increase the main jet circuit with a 20% larger jets (i.e. from 100 to 120). In other cases, you may need to go even bigger. I advice you to start with one size bigger main jet than you suspect will be needed and work your way down from there.
As for the idle circuit, it is usually enough by increasing it just one or two sizes (i.e. from 40 to 42 or 45). This applies in most cases.
Do not expect Braigasen to come up with suggestions on how to jet your specific carburetor. All bikes are unique and there are no short cuts - it is always a matter of trial and error! I have worked on cv-carburetors that needed as much as 60% larger main jets before we were finished.
Exhaust bangs on engine breaking?
If you let go the throttle and experience bangs in the exhaust - and you know with yourself that there are no air leaks - then try with opening the Idle Mixture Screws a tad further.
Hesitation and jerking when going from half to full throttle?
Try a larger main jet and see if the problem disappears. *
It feels sluggish at full throttle?
If you cannot feel any major change in speed when going from 3/4 to full throttle, then the main jet is probably too big.
If it does not respond willingly up to half gas?
Try shimming the needle. A 0.5mm shim is often enough.
Air filter location?
When mounting pods directly onto cv-carburetors turbulence often occurs, especially in the sensitive part of the carburetor where we find the venturi and the vacuum slides. For this reason, it is recommended to mount the filters on extension pipes, approx. 70mm long. This will calm down the air flow and make the carburetors easier to jet.
* If you find the changing of jets laborious... then you can take the shortcut and cover the filters. If it runs better with air restriction, then you must increase the main jet size. If it runs worse, then decrease it.