How are Keihin Jets measured?
On Keihin the size is the bore in mm i.e. a 150 main jet has a bore of 1.50mm. Hope this helps Dave. The jet number represents the cubic centimeters of fuel a minute that will pass through the jet at a low pressure-a head of 1ft. (30cm).
How do I know what size jets I need?
Consult your manual first to find the stock size. Also pay attention to the numbers on the side of your old jets, which you’ll be able to see in the steps to come. A larger jet number means a bigger hole and more fuel. A smaller jet number has smaller holes and should be used if your engine needs to run leaner.
How do I know if I need bigger jets?
Bigger the jet, the more the gas. More gas will cause your engine to run cooler because there is more wet stuff entering your engine; however, too much wastes gas and may foul things up. The only way to really figure whether you need bigger jets is by looking at your spark plugs.
Do I need a bigger main jet?
A larger jet number means a bigger hole and more fuel. A smaller jet number has smaller holes and should be used if your engine needs to run leaner. Whether your machine is running too lean or too rich is a good starting point for choosing your jets, but using a jet calculator minimizes trial and error later.
Are carburetor jets universal?
Yes you can. As long as they are the same style of Keihin jets.
How do you measure the size of a jet?
The suggested change in jet size is to go down one jet size for every 1,500 feet in density altitude you go up. Conversely, for every 1,500 feet you go down in density altitude, go up one jet size.
Do all jets fit all carbs?
Different carbs take different style and sized jets. Theres not 1 style jet for every keihn carb.
What is the equivalent of a Keihin jet for a carburetor?
For example lets suppose that a Mikuni carburetor has a size 100 main jet in it, the equivalent Keihin jet would be a 110. After the carb swap to a keihin carb start with keihin 110 jet.
Where can I buy genuine Keihin parts?
Main jets and needles are also available from Sudco which is a preferred source for genuine Keihin parts. Supposedly the experts at JD Jetting sell a custom made needle that is supposed to be ideal for the PWK carbs.
What jet do I use for a Mikuni carb?
Question, I am swapping a Keihin carb for a Mikuni carb, what jet do I use? The table below may give a place to start. For example lets suppose that a Mikuni carburetor has a size 100 main jet in it, the equivalent Keihin jet would be a 110.
What size jet should I start with after a carb swap?
After the carb swap to a keihin carb start with keihin 110 jet. The chart will not be a perfect match because there are many variables, for example, different carb flow characteristics, different needles, orifices etc. but it is a starting point. Question, I have some dynojets and would like to purchase Jets R Us jets, how do I compare the sizes?