I9 Hydra Hub slipping under sprint power?

Anyone have this issue? Overall I have loved the hub and it’s high engagement… when it is working, but I am having to clean/re-grease every 10 or so outdoor rides to keep it from slipping. I live in southern CA, so it isn’t like they are getting doused like in the PNW. Email into support at i9, but waiting to hear back.

Grease helps it not slip? Grease can hold the springs/pawls back, I would try less grease or thinner grease.

There could be a lot of things going on here. The place I’d start is with your grease. What are you using, and how much? The only grease you should be using in a hydra hub system is DuMonde Tech freehub grease - it’s very thin, and even so you really only need a tiny amount. Anything heavier could be causing slipping. You may also try using DuMonde Tech freehub oil instead, which will make the hub slightly louder. Again, you don’t need much, a drop on each pawl will do.

Yes, there are other oils and greases in the world. Not all of them are appropriate, and these two are the only ones spec’d by the manufacturer. I use both on Hydra hubs in the midwest, and haven’t heard of any skipping issues. But your issue may also be something different.

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agree with both of these. lighter grease and oil. inspect the pawls as while you’re there and actuate the pawls with your finger. while you have it off, take a look at the drive ring too.

Thanks all. I found this worked by process of elimination. Clean/fix one thing at a time and see if there is a change. This service has been the only thing that has “worked”. I also have experimented with different amounts of grease (Dumonde ProX) and found a direct correlation between the amount of grease I use and the time between a required service interval (less grease and I may only get 4-6 rides, but if I overdo it, I can get 10-12) seems counterintuitive to me also, which is why I am here. I’m 6 intervals in and I can now tell when it is about to fail by the sound change. I have not tried the oil yet, so that’ll be next on the list. Pawls and drive looked good previously, but I’m about to open it up again so I’ll give it another check. Thanks again

When you crack it open for service, take a photo of the freehub pawls and the drive ring - I’d be curious to see.

Clearly you should do more endurance workouts and hope your sprint power decreases…

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Will do and thanks again. Sound tells me that I have a couple rides left, so it should be within the week for the photos.

For longevity’s sake, try to keep it under 3,000 watts.

Things Lasted longer than expected which meant that I had time to get the dumonde oil. Holy “whzzzzzzzzzzz”. That makes an incredible sound difference.

Attached is the photo of the pawls. I didn’t realize when I was taking it but the photo of the ring turned out too blurry to be useful. Inspection-wise it looks to be in good condition.