Fork oil weight?

Hey everyone. I see the manual calls for Yamaha 1 fork oil. There wasn't any of this in stock at the dealership, but the parts guy said it's equivalent to 10W. He appeared to look this info up somewhere on his computer. So I took my forks to my mechanic yesterday to have new seals put in, and he says 10W is unusual for cartridge forks, and it's more likely to be 7W. Does anybody know what the proper weight is?

Thanks a lot for your help.

my last bike was a cr250r....i was using the pro-honda showa fluid in 5wt....on the bottle it stated that it is also suitable for replacing the kayaba/yamaha "01" fluid. i also noticed on other brands of fluid that the "01" spec fluid is listed as a very light or ultra light oil being in the 5wt range.

with the wrr forks already being kinda harsh,personally i would opt to stay with a 5wt.....7wt would be ok but it would be a step in the wrong direction in my opinion.

Don't use 7...it's meant to use 5.

I gaurantee the bike is not meant to use 10w.
Many have debated weather it is supposed to be 5 or 7.
I'm planning on putting in Ohlins 5 but I keep not getting to it.

I wondered myself , and was told by both the tech and a friend who builds suspensions. Use the 5.

Great info guys, thanks. 10w didn't seem right to me, but I'm a street guy, so thought maybe it was a dirt thing. Glad I checked with folks who know rather than trusting some punk at the dealership. Saved me a lot of headache. (Not the least of which would have been taking that first jump with the front forks stiff as steel pipes.

10 is good for an old fashion damping rod fork like found on the KLR
Cartridge forks usually use 5 or 7

I made the mistake at first too. I had a bottle of 10 on the shelf and pulled apart the front end of the WRX. I've never had a 'dirt bike' with decent suspension so assumed it would be damping rod style. one look at the oil that was in there it became obvious that it wasn't 10 wt, so I put is back together until I could get some 5wt. Now I've had two bottles of 5 wt sitting here for weeks and haven't gotten around to it again since.

I tried 10wt in my Z1000 for a while. It was OK for the track, but felt totally solid on the road. I can't imagine what it would be like in the big WR forks.