CBX photo and FCR acceleration pump discharge timing tuning

This article can be read in about 7 minutes.

CBX photo and FCR acceleration pump discharge timing tuning

I rarely ride my bike without thinking about anything.
I think it would be more meaningful to make some changes to the FCR before riding the bike.
I've gotten into the habit of touching something before I run by myself.
I would like to post a photo from when I took a test drive to Yasunohana Station the other day.

↓ Google Maps will open in a new tab. ↓
Yasunohana Station

If you take photos on a sunny day, the effects of camera shake will be reduced and you will be able to take very clear photos.
After the test run, adjust the discharge timing of the FCR acceleration pump while watching the air-fuel ratio meter.
Let's start!

Tuning of FCR

[Current tunings]
AS-2.00 minutes
PS-3.00 minutes
Acceleration pump diaphragm KLX250
Acceleration pump discharge timing 1.7mm
AS Uotani SP2-Ignition [1]

The discharge timing of the acceleration pump was changed from 1.9mm to 1.6mm and then 1.7mm.
I touched AS, etc., but I ended up changing it back so I haven't touched anything.
I just reconfirmed that the current tunings are good tunings according to my own feelings.
I wonder if it took more time to attach and detach the cab.
In the end, I made the plate width 0.1mm wider in terms of measurements.
If the discharge timing is made faster, the throttle valve will be damaged when the throttle is suddenly closed.
The fuel discharged from the FCR's accelerator pump will directly hit it.
I do not want to advance the discharge timing of the acceleration pump by more than 1.6 mm.
The timing of discharge seems to be good even in the current state.
When the engine suddenly starts up, the air-fuel ratio meter shows rich in the 10s.
Make the diaphragm even smaller and run a test run to see how much the total discharge volume changes.
There is a problem if the accelerator pump is too rich.
The feeling of acceleration will be impaired.
It's fun when the accelerator pump is working properly.
It's worth pursuing.

CBX Photos

Taking pictures in direct sunlight on a bright, sunny day is very pleasant as you can take beautiful pictures.
By the way, direct lighting is one of the techniques when taking photos.
If you take a photo with the sun on your back, you will get a better photo. If there is a photo on the side, it will be obliquely lit. You can take photos with a slightly lighter and different atmosphere.

For FCR beginners – don’t worry about fuel efficiency

You may have heard that FCR improves fuel efficiency depending on the tunings.
I don't really care about fuel economy.
In theory, a racing carburetor consumes a lot of fuel to produce power.
This is one way of thinking about the tuning of a racing carburetor.
I'm not tuning it up to pursue fuel efficiency.
There are bound to be cases where the proper tunings result in higher fuel efficiency compared to the previous tunings. Seeking power is connected to how efficiently and how much fuel is consumed.
Fuel consumption varies considerably depending on how the rider rides.
I have ridden with an intercom and compared the oil temperature with other air-cooled motorcycles.
The oil temperature changed by about 10 degrees depending on how I drove.
There is a huge difference depending on riding.
Fuel efficiency may be the best if the tunings are appropriate. Even if it is too lean, the engine will spin.
Even if you get too rich, fuel consumption does not change by even 0.1%.
For reference, when I drive my CBX, the fuel consumption is approximately 11km/l.
If anything, I tend to rev the engine and increase speed.

CBX photo and FCR acceleration pump discharge timing tuning【summary】

It's a lot of fun to just go for a test drive on the FCR without thinking about anything.
Currently, I have roughly decided on the low throttle opening position, so next time I will increase the driving time.
If there are any concerns, we will make changes at any time.
Recently, I often set up the accelerator pump.
I will try various things little by little.
I hope everyone has a fun FCR life.
Well then, see you again!
Copied title and URL