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This article is about the test run and tunings after changing the light dial of AS Uotani SP2.
This is a tuning change due to a change in ignition timing.
I was thinking of dealing with it by changing the accelerator pump or clip.
However, I think it is better not to include the acceleration pump as the main tuning item.
I think it is desirable to have something that compensates when you suddenly open the throttle or open the throttle.
FCR does not allow much tuning of the accelerator pump. It appears that TMR can also be used to set the accelerator pump. I would have been happy if TMR had a lineup for CBX, or rather a kit.
It seems that there are no plans to release it in the future. I've gone off topic, but I'd like to write about the tunings.

FCR-tunings-JN clip change

Current tunings
AS-1.35 minutes
PS-1.15 minutes
AS-1.35 minutes
PS-1.15 minutes

I test drove AS Uotani SP2 with ignition timing set to [1] and [2].

AS Uotani SP2 ignition timing [1]
AS-1.35 minutes back
PS-1.15 minutes
It feels great with no particular problems.
Would it be a good idea to increase the acceleration pump or increase MJ by one step?
I felt that there was no need to make any changes.

AS Uotani SP2 ignition timing [1]
AS-1.35 minutes back
PS-1.15 minutes
It's a great feeling. I thought I'd like to proceed with the tunings.
However, I was worried about whether I could handle it with the MJ etc. I had on hand, and I was worried about tuning it up.
Since it seemed like it would take a lot of time, I decided to use tuning ① this time.
If you open the throttle more than 1/2, it feels like it gets bumpy, so I'm thinking of countermeasures such as increasing MJ, increasing the straight diameter of JN, or increasing the acceleration pump.

Checking the FCR fuel adjustment on AS Uotani SP2

This is just what I'm thinking right now, but when I touch the ignition timing dial,
If the carburetor doesn't go out of order, I think the tuning is not very good.
If you advance the dial, the overall tuning will be leaner,
I feel like if I retard the dial, I get a richer tuning.
It may not be a very good point of view as it is a simulated situation, but I think it is worth giving it a try. It's a simple task, just move the knob one step.

Photo of CBX FCR tuning in progress

For FCR beginners – tuning order – As much as possible

I will write down the order of tunings. If possible, please equip it with an air-fuel ratio meter.
I will explain everything starting from preparation.
According to the manual and the words of a famous tuner, everything is in perfect condition.
However, it is clearly impossible for the average rider to fix the low engine compression. We have no choice but to touch it as much as we can, assuming that everything is in perfect condition.
Please try to troubleshoot as much as possible until the problem worsens.
There's definitely something to be gained.
First, make sure the oil level is at a uniform height. Accuracy is not necessary, but
The ideal height is just before overflow. It's not in the manual, but turn the FCR over and
It is also possible to set the height of the float to about 6mm. There is no problem even if the accuracy is not high in this area. I think the chamber is open, so close the chamber gasket and check to see if there is any gasoline leaking.
Next, you can roughly check the alignment using your eyes or a ruler. Synchronization is good if you do some light racing while idling and the tachometer does not get stuck at a level that interferes with driving.
It is better to set the PS back 1.0 minutes or 1.15 minutes and avoid touching it as much as possible.
For tunings, the first priority should be to change the AS and JN clips.
If SJ is CBX, I think if you put 42 in it, AS will be within 1.0.
I don't think there will be any problems with MJ's initial tuning around 120.
There are changes after touching the AS and JN clips, so from now on based on that,
You can think of things like making it leaner or richer.
Is AS suitable for driving well when the clutch engages?
You can take a look at it. You can try it on a hill with only a slight incline.
About the throttle opening from Clutchy meat to 1/8,
You can see the change even if you touch AS for 5 minutes at a time. There is also a balance with PS,
Regarding PS, it is basically easier to work in the direction where you do not touch it.
The premise is that you will be able to drive to some extent.
The task is to look at the changes between last time and this time.
Please try doing some research or asking your friends.
Then, I think you should gradually buy more jets that you think are necessary.
An air-fuel ratio meter is always required. Also, by having an air-fuel ratio meter, you can share information with others.
This is a wonderful item that allows amateurs to suddenly be able to talk about specific air-fuel ratio values like a veteran.


I am conscious of the tunings that take into account the ignition timing of AS Uotani SP2.
Is it necessary to adjust the ignition timing of the light dial depending on the season?
Or is the ignition tune a forbidden fruit that should not be taken lightly?
There are a lot of things I don't understand, but for now I would like to use the average 4 degree lead angle in [2].
I am thinking. I think that at least the average 2 degree lead angle in [1] can be used without any problems.
The temperature is currently summer-like, but it seems like there will be no need to worry about retardation, at least in the summer.
Riders who don't often ride at full throttle don't need to worry about advancing the ignition timing, but I'm very concerned about it because it can melt the piston and cause damage to the engine. Masu. I think this is not a problem for people who know how to use a spoonful. Plug melts when fully opened
The problem is that the combustion chamber may melt. It's hard to tell if the engine is knocking or not, and it's too late once the knocking has caused damage to the engine, so we have to be cautious. If you want to ride at high speeds, I'm thinking about changing the plug from the current No. 8 plug to a No. 9 plug. However, I'm using a No. 8 plug and it feels good, so I wonder if that's a little different. It's fun to spend time thinking about these things, so I'm going to take my time and think about them.
I hope you have a good FCR life!
See you again!
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