Hawk Rear Sprocket Failures - reason why.

[o2jmpr]

Thanks so much Megadan! This was bothering me for the last few weeks. I've had this problem and I also recently noticed that my rear swingarm was crushed after torquing to "specs" and I've read tons of wheel bearing issues also so I took everything off for inspection today.

The wave washers totally eliminated ALL wiggle in the sprocket. I feel much safer now. I also found that none of my inner races (Front or rear) would spin freely. I apparently crushed the bearings inner races too tightly on the internal spacer tube. I'm replacing all my wheel bearings now and only putting the axles back on until my judgement says they're tight. I'm not using anything north of 30ft lbs for sure and probably less. I just don't think the China steel can handle it.

[Megadan]

Originally Posted by o2jmpr

Thanks so much Megadan! This was bothering me for the last few weeks. I've had this problem and I also recently noticed that my rear swingarm was crushed after torquing to "specs" and I've read tons of wheel bearing issues also so I took everything off for inspection today.

The wave washers totally eliminated ALL wiggle in the sprocket. I feel much safer now. I also found that none of my inner races (Front or rear) would spin freely. I apparently crushed the bearings inner races too tightly on the internal spacer tube. I'm replacing all my wheel bearings now and only putting the axles back on until my judgement says they're tight. I'm not using anything north of 30ft lbs for sure and probably less. I just don't think the China steel can handle it.

Glad it worked out for you. I have a feeling the snap ring groove was machined juat a bit too far out. I would recommend getting the honda studs as well. The factory studs just have too much play, at least mine did.

The wheel bearing issues are seemingly another common issue with the 2017 bikes. My rears were also locked up. Same with the swing arms. I tightened mine until the wheel spacers seated gave gave them a snug up after that. I also used loctite 242 on the axle nut just for assurance.

[Megadan]

Long-ish term update. Since doing the last fix I have logged over 700 miles on the bike, and I am happy to report that my sprocket is still rock solid. I am confident enough at this point to give my own seal of approval on the wave washer/shim method to take up the gap between the sprocket and snap ring. I still highly recommend getting NOS Honda studs to replace the factory ones, but it may not always be necessary.

[Fodarr]

Did you trim the wave washers to match the stud with a rounded section cut off or just tighten down till it squashed flat?

Originally Posted by Megadan

Long-ish term update. Since doing the last fix I have logged over 700 miles on the bike, and I am happy to report that my sprocket is still rock solid. I am confident enough at this point to give my own seal of approval on the wave washer/shim method to take up the gap between the sprocket and snap ring. I still highly recommend getting NOS Honda studs to replace the factory ones, but it may not always be necessary.

[hertz9753]

Do you have links the hardware you are using?

[Megadan]

Originally Posted by Fodarr

Did you trim the wave washers to match the stud with a rounded section cut off or just tighten down till it squashed flat?

Since I used a smaller stud size, they fit within the groove without needing any trim work, save a tiny little lip, which I just left on and they deflected around. The wave washers are so thin they don't take much force and bend relatively easy. You could trim them up if needed though.

Originally Posted by hertz9753

Do you have links the hardware you are using?

The studs were the Honda part number listed at the top of this page in my post. The rest of the hardware came from the local hardware store.

[hertz9753]

So I order the studs and go to Ace Hardware. Did you use stainless nuts?

[Megadan]

Originally Posted by hertz9753

So I order the studs and go to Ace Hardware. Did you use stainless nuts?

Sorry I didn't post more details sooner, so now that I am on my actual laptop on not my phone I should probably list it all in one spot.

As far as the studs, there are two options.
1. The studs I am using, which are an M8 thread and will use the smaller set of holes in the JT Sprockets, but will be too small for the stock sprocket which only has one pattern.
Part #: 90128-361-000

2. Alternate part number, and an M10 thread. These would be a more direct replacement to the stock studs, although I don't know if the thread pitch is the same. I may order these in the future, but I am happy with my current ones. These would use the larger holes on a JT sprocket, and would also work with the stock sprocket.
Part #: 90128-KE2-940

As far as the nuts, yes I essentially went to Ace Hardware and picked out some "serrated" flange head nuts. I did not use Stainless, but only because they didn't have any M8x1.25 flange head stainless nuts. Your other option would be normal nuts, with a lock washer and normal washer under them.

If you do the studs and nuts, tighten it all up, and still have a little wiggle in the sprocket, then 4 wave washers did the trick for me. They tend to be very thin and made a great shim to take up the gap between the sprocket and snap ring that I had.

Something I also did, but is probably not necessary, was to put 2 or 3 tiny little dabs of Loctite 620 retaining compound on the studs. This was more done for insurance, and given the forces that the studs see, has probably already released anyway. If not...I may have fun removing the studs later as even a tiny bit of that stuff can be a bear to break free. So for that reason I would say maybe skip that part.

[silva]

Magadan will these work? http://www.2wheelpros.com/oem-parts/...-940-part.html

[Megadan]

Originally Posted by silva

Magadan will these work? http://www.2wheelpros.com/oem-parts/...-940-part.html

Yes, those will be nore or less a direct replacement.

[silva]

[csavvy]

Originally Posted by Megadan

Ok, so I am finishing up with my bike, going over the rear end right now and I do believe I have discovered why a few folks have had the kush drive bolts shear or the C-clip come out. I did not find this until I had the rear wheel off. With the chain putting tension on the sprocket, it did not move.



After installing my JT Sprocket....



For your own safety please check your bike, please please please!

After working with the stock Snap Ring, I do not believe these to be a weak point. Snap Rings are NOT intended to take lateral thrust loads, and if the sprocket has play like mine did, under power, it could be enough to eventually cause a failure.

Also, something I wish I would have noted in the video, make sure those kush drive stud flats - the ovalish shaped part that sits on the back side of the sprocket - are seated inside the channel on the back of the sprocket. If those are aligned wrong, one side will actually ride up on the outside of the channel and put a lateral load on the stud and it will not seat right to the hub.

I just got a new Hawk X. The videos have been deleted on youtube and I checked a few other sites but not there. Could you repost them or tell me where to find them? Thanks.