Main sprocket leak

So I fixed main sprocket leak last year. New seals and gasket. At the end of the season I noticed a small oil residue outside that area so I decided to inspect closer.

After removing the main sprocket bolt the oil już poured out of the hole. No noticeable leaks anywhere but this is a first time I see oil there. And I have done this repair on my f1 without any issues before.

Aby thoughts what happened there? Worth to disassemble and check what’s up?

Hi pablo, the shaft that the sprocket fits onto is hollow and should have oil pumped through it, the bolt that holds the sprocket on should have an O ring on to seal it, I always put a tiny little smear of gasket seal on the threads


That is good news. That means that I did not botch that job.

There is no oring on that bolt though, not on 3 bikes I own a this point. Are you sure it supposed to be there on the bolt? There are orings sandwiched between the casting though, maybe you meant them.

Some models did, some didn’t. I usually put a little Hondabond on each side of the clean washer.

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Hi pablo, yes I’m pretty sure all my vfs have the o ring on the bolt,

installation of oring did not solve my issue. I believe that I need a directional seal as generic one lets go if I drive at highway speeds.

Here is a picture of my leak

OEM seal looks like this

Never seen one without the O ring, part # 91305-422-000. 9.8X2.4mm. I’ve had 15 VF engines, they’ve all had them.