[rij1]

I've been persuaded (haha) to replace my fork oil again and go from my usual 5w to 7.5w (1st pic) which is equivalent to Yamalube 01 which is KYB 01/Kayaba 01. Its usually about $40+ shipped)

Many run 5w and many mix 5w and 10w to make 7.5w.
I wouldn't run anything over 7-7.5 weight as higher the number the harder the suspension but some shop that do the work on these bikes and the forks add 10w.
Nor would I run lower then 5w as the lower the number the spongier the suspension.
Here's some 7w, 7.5w fork oils to eliminate the mixing to make the Yamaha spec weight.
Or if you'd like to just run the 5w there's a pic of what I've always ran.
If your going to mix a 5w and 10w to make 7.5w look for 16oz of each since just a bit over 32 oz total (16oz each fork) would be needed in the forks.

These pics and fluids below are enough for both forks which are 1 litter per bottle.. There's plenty of other brands but this should be easy enough to come by.

Just for chits and giggles,
Here's some seal saver/cleaners that may help stop seal leaks. You can use a credit card aswell but this may help some guys. They might save you the trouble of replacing your fork seals. If used just remember to pop down your dust seal then use the tool.

Motion Pro Seal Mate 08-0395
Sealmate Fork Seal Cleaner (Each) - Motion Pro
Or
Risk racing Seal Cleaner small 00123
Seal Doctor

Here's fork seals with dust covers kits
There's only 2 trust worthy kits

Yamaha Oem kit 4EB-W003B-00 -
Yamaha 4EB-W003B-00-00 - FORK SEALS KIT | Partzilla.com
Or
All balls racing 56-129 -
56-129 - Fork Seals & Bushings | All Balls Racing
The dust seals with the All balls look unfinished but the kit is usually cheaper and still good.

Motul Factory Line Fork Oil SAE 7.5W

Bel-Ray High Performance Fork Oil 7W

Maxima Racing For Fluid 7WT/125-150

Motul Expert Fork Oil SAE 5W

Motion Pro Seal Mate 08-0395

Risk racing Seal Cleaner 00123

Oem Oil Seal and Dust seal set 4EB-W003B-00

All Balls Racing Oil Seal and Dust Seal Set 56-129

Fork Specs

 

[markmag]

Sweet, I'm having a leaky fork soo..

 

[WarriorCustoms]

Here's an Oil Chart to help with choices!!! 5w is Heavier than stock

Fork oil weights

 

[WarriorBKNY]

This is sooooooo helpful. Recently noticed heavy leaking from my left fork. I’ll be doing this job very soon. Thank you for the info 🙌🏻

 

[random_guy]

This is sooooooo helpful. Recently noticed heavy leaking from my left fork. I’ll be doing this job very soon. Thank you for the info 🙌🏻

Start with cleaning the seal. Last year, I started to have a slow leak on one side. I kept putting it off since it was such a slow leak but then the other side started leaking. I bought the Risk Racing Seal Cleaner and it worked like a charm. Couldn't be easier and now, no leaks! Best $20 I ever spent!

 

[Dr.RR]

I appreciate this post. You just saved me a headache.