Test run – Throttle opening 1/2 – MJ change – 22/07/08

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Test run – Throttle opening 1/2 – MJ change – 22/07/08

This is about the CBX FCR tunings.
I wrote about the results after replacing the MJ in my previous post, but I'll write about my impressions after a test run. I value test runs, but if you have an air-fuel ratio meter installed, you may get caught up in the numbers, so I try to be careful.
The purpose is not to chase numbers, but to run.
The fact that I was able to take nice photos is another reason why I only post test runs on my blog.

Rapid opening! Throttle opening 1/2

My CBX gets bumpy when I suddenly open the throttle from about 1/4 to 1/2.
When I look at the air-fuel ratio meter, it shows an unusually high reading. It's 10.1.
I just couldn't get it right, so I Change SJ to lean, kept the AS open, changed and adjusted the acceleration pump,
I changed JN to lean, raised the JN clip, replaced the MJ...
There was a change when I replaced MJ. It may be a placebo effect, but in my opinion,
There are changes! I decided that the combination of MJ and SJ would make it richer.
This is my impression after dropping MJ from 135 to 125.
MJ was currently feeling that the larger the size, the better.
It doesn't seem like anything can be done unless I lower the MJ, so next time I touch FCR I'll take the lowest step and set it to 122.
I actually think it should be lower.
As for the change in feeling when driving,
It became difficult for the air-fuel ratio to reach 10.1 when the engine suddenly started.
Also, the partial was around 12.0, but the feeling of acceleration was impaired,
Symptoms such as getting tired have almost disappeared.
At first, I thought it was due to the accelerator pump, but the symptoms did not improve even after I turned it off.
On the other hand, the accelerator pump seems to be working properly to counter the symptoms of leaning around 3/4 of the throttle opening.
I think so.
If you suddenly open the engine at high speed, the symptoms will be that you will get hit and have to wait for it to open.
go out.
I feel like the current tunings are very good, except for one thing I don't like.

CBX photographed during a test run

The sky was a little cloudy, and the red color looked very cool.
I didn't come here to take pictures, but I'm glad they were cleaning regularly.
The next thing I want to do after the test run is to set the current F taper to a point where I think it's good.
After that, I will change to an E-taper JN jet needle, make the MJ extremely large, and proceed with the tuning.


I have written this several times, but if you are thinking of starting FCR tunings,
We absolutely recommend installing an air-fuel ratio meter.
As long as you purchase a wideband air/fuel ratio meter, it doesn't matter what price you buy.
It is necessary to process the muffler to install the boss, but I am looking forward to a wonderful FCR life later.
When you think about it, there's no need to waste time. If you are in an environment where you can consult with a veteran or someone,
It may work out somehow, but it's best for amateurs to start tuning up the FCR by fumbling around.
Is difficult. Don't rely on the burnt color of the plug.
If you have an air-fuel ratio meter, you may be able to reach the same potential as a veteran who does not use an air-fuel ratio meter.
This is a highly recommended part.
Also, it is best to mount it in a position that is as easy to stare at as possible.
I am not installing an additional meter, but replacing it with a normal voltmeter.

Test run – Throttle opening 1/2 – MJ change – 22/07/08【summary】

CBX requires approximately 6 tuning parts.
And the JN jet needle is an expensive tuning part, and it is difficult to set unless the straight diameter number is also aligned.
From the time I started tuning up the FCR, I thought I wouldn't mess around with the taper.
I am planning to purchase this for my next tuning.
For throttle opening 1/2, it is a combination of MJ and JN.
A rod called JN is moving in and out of the hole in MJ.
MJ probably has a change of 0.02 or 0.03mm at No. 1, but JN's straight diameter is only 0.01mm at No. 1.
No change. Even if you change the straight diameter drastically, the change will not be large.
I can't help but want to know what happens when I change the taper, so after changing the taper,
I'm thinking of making MJ bigger.
Changing the number of clip stages on the JN has an amazing change in driving feeling that doesn't show up in the numbers.
I'm worried that if I fix one thing, problems will arise elsewhere, but once you know things, you gain experience.
It will be easier to predict changes, so you can have fun with the tunings as you go along.
I hope you all have a fun FCR life!
See you again!
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