Fork Upgrade Kit

[How is it used?
GSX-S 125 2023 (DL32D), Rear is also converted to YSS at the same time.
The use of the vehicle is Light, including commuting, city driving, and day-touring.

Was the one you received as per Image?
YSSQuality as usual. No problems.

Was the installation difficult?
I asked the Shop to do this for me. The FFork oil that came with the kit seemed to have a very hard number in it. （The FFork oil included in the package seemed to be a very hard number, but it was less than one bottle, so it was supposed to be mixed with others.)

How was your experience with it?
The viscosity of the supplied FFork oil seems to be very hard. I was wondering what to do after reading other reviews, but I decided to give it a try and used a mixture of the supplied oil and OEM FFork oil.
As a result, I could feel that the system was working properly after the conversion, although I could not feel it working well in NORMAL mode for my above application.
However, the oil is definitely hard, and it does not seem to be soft or move well. On public roads, there may not be a situation in which the oil is at the full bottom.

[Included Parts:were they on?
Instruction manual, FFork oil (I forgot the volume, but not the full amount)

[Was there anything that disappointed you?
Nothing in particular. It has an adjustment mechanism, which I would like to try out in the future.
I have changed to YSS both front and rear and now have a normal suspension, which I think is safer, more comfortable and more pleasant to drive than NORMAL, including the behavior when stepping on the Gap and the overall ride quality.

I asked Shop to do the installation.
If I can remove the top cap, I may be able to do the work myself. Since I will be using it in a mini circuit, I would like to change the oil viscosity depending on the time of year, so I am thinking of trying this at some point.
YSS recommends viscosity No. 30, but it is too hard for my 60kg weight! So, I use Yamaha's No. 15 for now in winter, and it feels good.

Balance is good as it is now with YSS front and back.

I can recommend it.

It is supposed to be for GSX-R150, but I bought it for GSX-R125 because the distributor's website said it was for both 150 and 125. As a result, I was able to install it without any problem.
I also purchased this product as a Circuit Running and am satisfied with its perfect performance.
The installation process is a piece of cake if you have ever done a Fork oil change. Even if you have never done it before, you can do it if you have some tools. We recommend that you change the fork oil while doing the work.
The top cap of the fork is not screwed on like the FOR JAPAN MODEL production type, but only stopped by a C-ring using the force of the fork spring, so it requires a bit of hang, but as shown in the photo, it can be removed quite easily by using a Tie Down Belt and TWrench, etc. However, it can be easily detached by using a Tie Down Belt and TWrench as shown in the photo, or by preparing a 3-way Vise.
The Instruction Manual for the product is very unfriendly, but it seems to recommend an OilLevel of 125mm, so you will need about 200cc or less of Fork oil on the One Side when replacing. Also, although Fork Oil No. 30 is included in the package, it is not recommended to use Fork Oil No. 30. Use this with a Single Body. I don't think that's the case (it's only 250cc so it will run out after only One Side). I think the OEM No. 10 has enough viscosity, so you can mix No. 30 to your liking.

Purchased for GSX-R125Circuit Running.
The rear suspension was too stiff and didn't stoke at all, so I replaced it with a YSS kit.
Although I haven't run it yet, I can see the change just from the feeling of stroking it.

Installation was not particularly difficult, except for removing and attaching the Circlip.
OEMs also don't need Impact or Special Tool because they only need to remove Cap, Color, Washer, and Spring without making it all Rose.
The specified oil was #30, but I was scared that it would be too hard, so I decided to use KYB #20. I'm going to run it and see how it goes, and then I'll try the specified oil.

Basically, I agree with kamayan27, and I'll limit myself to talking about it in Race use.
Brake initial behavior is good, which cannot be handled by changing oil viscosity or oil level.
The lack of spring rate will be eliminated, the Construction Manual says, and Not by volume, but by volume of PD Valve.
Since the oil level will be raised 20mm, you need to adjust the oil level after feeding the Valve.
If the remaining stroke is more than 20mm in the course, the Oil Lock Piece can be used. It is not considered a problem. KYBOil No. 30 with proper elongation and pressure damping.