Following the sequence the team is accustomed to the rear axle is next, and they got some work getting some good shots!
The rear axle is 11.5 inches long with a diameter of 15 mm. The bolt head is 15 mm and nut 21 mm so here we go again I need to find a lightweight wrench of 21 mm. The standard one from my box end is big and looks to weigh a lb. So to take the axles off front and back you need a 15mm, 18mm, and 21 mm.
The axle adjusting spacing hardware seems massive compared to the HAWK and should handle any necessary torque placed upon it. Let me say I am not trying to disparage the HAWK, it is just a good comparison reference for me.
The sprocket is 46 teeth and is attached to part of the cush bearing interface with its own bearing. PIX shows sprocket side and backside.
The bearing is BUC 6204 RS
The hub and brake drum contain the cush bearing (rubber fits to hub) with bearing CXCL 6202 2RS/X1
The cush bearing absorbs that initial shock from the drive chain when you pop those wheelers I believe, but any expert can chime in whom knows more about it.
The hub is aluminum with a steel insert for the brakes shoes to ride against. The diameter of the Hub on this bike measured at 129.46 mm. We can see stamped inside the hub is a maximum diameter of 131 mm. So when wear exceeds this number it should be replaced.
The brake drum side of the hub uses bearing CXCL 6302 2RS/X1
The brake shoes are held in place with springs keeping them against the lever top and pin bottom. The diameter of the installed shoes measured 128.80 mm.
Braking force is applied mechanical by linkage and you can see in the PIX a rod rotates that rounded square side lever against the brake shoes forcing them out against the drum. Looks like they have put some grease on the actuator which is likely high temp. A sign of quality manufacture and quality control.
Outside PIX of the brake lever and rod
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Front drive sprocket 15 tooth held in place with retaining clip and bolts.
The stock chain is 428 with 128 links. With prior bikes I would always oil up the stock chain and drive it for awhile, eventually switching over to an O ring or X ring. I have finally learned there is no cost savings in messing with it when considering my time, and I have ordered a new X ring chain to install from the get go. On the backroad they just work better IMO.
Thoughts: The team was a little surprised to see there are no grease seals to protect any of these bearings. I have never worked on a motorcycle drum brake for reference but it would appear this likely a well established lay out. Maybe somebody with experience can comment. The other thing you wonder about is why not upgrade to a rear disc brake. The only thing I can figure is this model was EPA approved and any modification requires more money/ approval. As we have seen, a small cover protects those bearings and I would not trust that to provide to much water protection. I ordered some waterproof grease with a high temp point and will put a light coat on the outside of the bearings and the axle to add some more protection, understanding that grease attracts dirt. These brakes generate heat and you don't want to put some cheap grease on that will melt and run down on your brake shoes and drum. If you soak it in the river, may require some maintenance. Brake drums have been used on cars and motorcycles a long time so I don't anticipate any issues.
The story is caught up, time to turn some wrenches this PM.