I am the owner of a Honda motorcycle [CBX1000] who lives in Hiroshima City, Japan. I am posting about FCR carburetor and CBX1000 customization. I also post about things other than cars and motorcycles. We will post information that will make bikers around the world happy.
Today, I was driving in the morning, and the throttle opening was from 1/2 to full throttle, and it felt very rich. Fixed. SJ45→42 MJ132→128
The final tuning is SJ-42 PS-2.20 minutes return AS-2.10 minutes return JN-90FXM#2 MJ-128 Uotani ignition timing [1] Acceleration pump diaphragm is KLX250 Discharge timing is 10mm
I feel like the screw is set back too much, Is it because of the temperature? Or am I just feeling weird because of the temperature? It's within the adjustment range, so I'll take it as good.
With SJ45, I felt like the screw was opening too much, so I changed it to 42. I chose 42 because I wanted to make fine-tuned tunings, but 40 might be the perfect range for all year round. I feel a little regretful that it might not be necessary to make it look strangely deviate from Bito's initial tuning. When I checked MJ using an air-fuel ratio meter, it was clearly too rich, so I adjusted it to a lighter level. If you are concerned about the full opening range, it may be a good idea to change the tuning by two steps or by a value of about 10. Be careful as it will definitely be affected at around 1/2 throttle opening. When changing SJ, prepare a spare chamber packing. After installing and removing the caburetor, check the synchronization. Adjust the height of the two legs at the beginning of opening using the stop screw. Adjust the previous height of the two legs by pulling the throttle wire. I did something like this. The stop screw and throttle wire are adjusted visually.
My doubts about CBX1000 PS
In my case, there is no one to answer any questions I have, and the only way to confirm the answer is to try it myself and evaluate it myself, so when I come across a case where the answer is unclear, I get very troubled. . That is the appropriate amount of PS to return. Currently it is 2.20 minutes return. Until a while ago, I was trying to set it back by either 1 or 1.15 minutes return, but Perhaps because I'm currently adjusting the JN and ignition timing, I feel that tuning it back by 1 or 1.15 minutes is not appropriate. In order to keep the air-fuel ratio to about 13-15 when the throttle is fully closed, the PS is turned back about 2 turns. Even when I watch videos of tuners that appear in magazines, they tend to go back 2.15 minutes, so I don't think the answer is wrong. I received a comment from a senior tuner who rides the Z that it would fit around 15. I feel like it's good the way it is now. I have the impression that the air-fuel ratio at idling is roughly determined by the combination of JN and SJ. Until recently, when I adjusted the screw to what I felt was good, it was generally around 12. Currently, it seems to be around 14-15. The big difference between the above and below is the number of clip stages of JN. Especially as the number of clip stages increases, the starting position of the JN's straight diameter becomes leaner, so I think that this may have an effect.
For FCR beginners – Working outdoors
This time I replaced the SJ outdoors. Basically, we believe that you should not disassemble your motorcycle in a flashy manner when outdoors. The reason I disassembled it outdoors was because it wasn't a fancy job for me.
I decided what I was going to do in advance, and I also brought spare parts with me in case an unexpected situation occurred.
This is the reason why I was able to do the work.
When tuning up FCR, outdoor work will always follow.
Here are some things you should keep in mind when doing so.
① Pay attention to the weather
②Secure emergency contact information
③ Prepare spare parts
There are three points.
Regarding ①, since it is outdoors, it would be very unfortunate if it suddenly started raining.
Please pay attention to the weather.
② means that it is better to work on days of the week and times when friends or shops who can help you if you lose a part or something unexpected happens are active.
③ Prepare parts that are likely to be lost or damaged, such as gaskets and JN clips, beforehand.
This means that you should do some outdoor work.
Basically, it's best to decide what you're going to do when it comes to outdoor work, and then limit it to the bare minimum.
FCR tuning – SJ and MJ change – 2022-08-15【summary】
The big thing I learned this time is that you shouldn't do any flashy disassembly outdoors in the heat, which could lead to heatstroke. Basically, I try to touch the FCR tunings as soon as I'm interested.
It's fine to touch things haphazardly, but I think we also need to be mindful of environmental factors.
I checked for rain, but the sun was too strong and it was pretty scary.
When riding a motorcycle, please take sufficient precautions to avoid heat stroke.
See you again!
*Work photos are posted below.
work photos
Although not shown in the photo, after installing and removing the carburetor, adjust the throttle wire and synchronize the carburetor.
I definitely go there.
