MBc-Member Product Review: GruBee Solid Hub Heavy-Duty Axle Kit

[alesterfeind]

Ok, I got my new axle, hub and sprocket yesterday by FedEx from bicycle-engines.com. I called them on Tuesday and got it on Saturday. This is the 2nd order I have made with this vendor, and they have been very quick to deliver both times.

Now, about the hub:

It's HUGE! The picture on the website does not really give you an idea of the size of this thing. I had planned on threading and building my own wheel. After getting it, I realizd the diameter is bigger than my other axle, so I have to replace the spokes as well. I took it up to the bike shop along with my wheel to talk to the techs about it. And, just so everyone knows, the guys at Bicycle's Plus here in Flower Mound were really cool about it being a motorized bike. One guy mentioned, "I have seen a guy riding one of these going north on FM-2499." I said, "That was me!" They can't wait to see the bike once it's put together.

After talking about options, I decided that if I am going to put any more money into this, then I am going to do it right. I purchased a heavy duty rim, (2 ply), new spokes, and I am letting a tech build it so it will be true when I put it on. It was $35 for the rim, $18 for spokes, and $45 for labor. So, it's going to cost about $100 to build the wheel around this new hub, and the hub cost about $50 with S/H. I really think the end result will be worth it in the long run. This new wheel should last forever and run much smoother compared to using the assembly kit we get with our engines that compresses and bends the spokes.

One great thing about this hub is how easy it will be to interchange different size sprockets since it just screws onto the axle. My hub kit came with a 44T. When Andrew gets his, I am sure he can come up with some custom sprockets to fit. I really want a 36T or 32T for my bike.

I should have it ready by this next weekend, and I will post pictures of the parts and the final result.

 

[Alaskavan]

If you have to start your engine by pedaling, you would need the solid hub (sans freewheel). If you have a pull (or electric) start, you can use the freewheel hub and the bike will ride better when you're pedalling with the engine shut down.

 

[alesterfeind]

Actually, by solid hub, we are referring to the hub/sprocket that attaches directly to the axle, instead of using the assembly that attaches the sprocket to the spokes. This provides a direct drive to the axle, with no stress or bending of the spokes for what should result in a much smoother, faster and safer ride. That is yet to be seen however.

You can get the solid hub with the freewheel so you would use with hand brakes, or with a brake that works right at the hub.

 

[HoughMade]

Nope- Alaskavan is correct. Way back in my mind I knew that...way, way back. In this context- both the hubs have a mount for the sprocket.

I have the 4 stroke Honda GXH50...inching so closely towards a test ride....I'm thinking of getting the freewheel.

 

[alesterfeind]

Ok, right, I see what you mean. I am more referring to the difference in the HD Hub that we are reviewing versus the hub that comes with the kit.

 

[alesterfeind]

Which now makes me realize my hub won't work. It is freewheel. Josh at bicycle-engines.com says that the solid hub they have will not fit the axle that I bought, so they discontinued them. Therefore, they don't have anything available for the 2-strokes. He did give me a name of someone who might have some information on an adapter for the axle, and I will report back.

So, I am back to square one. Alakavan should be fine since he has the 4 stroke engine set up.

 

[Alaskavan]

Alester, perhaps all is not lost. These style of freewheels are not made to be disassembled, but... Sheldon Brown's site has a section on destructive disassembly of freewheels. If you could open it up without damaging it too much, perhaps you could weld the insides of the freewheel solid. Better yet, maybe you could weld it on the outside.Then you'd have a sprocket attached to the hub instead of the spokes. Have to be careful not to warp anything. I don't know that this is possible, just trying to help.

 

[andyinchville1]

HI all,

I was going to get a sprocket off this hub sent to me from a potential customer to make them a custom sprocket but when this customer received his hub it was not what he wanted (and he did mention the hub was very heavy) so he was returning it for a refund.....so long story short, If there is an interest in custom sprockets for this hub I will need somebody to send me a sprocket off the unit for precise measurements....I mentioned this because in an earlier post there was mention I was getting one...but for now looks like that one fell through...But if anybody else is interested just let me know and I will try to help.

Andrew

 

[ocscully]

Questions?

Alesterfeind or Alaskvan,

Have either of you pulled the axle out of your hub. I'm curious as to weather or not there are shouldered cones for the bearing contact or does the axle itself bear on the inside dia. of the cartridge bearing? Also could either of you post the over locknut/spacing dimension of your hub? I don't understand all of the extra axle length on the left/brake side of the hub. Anyone know what thats all about? It would be very interesting to hear about the comments you get from the wheelbuilders you each use, as it appears to me that this hub is going to build up with alot of dish on the left side. I don't know that this is a bad thing for a motored bike application its just different from most bicycles. In a perfect world you want to have symmetrical / dishless wheels. Adding dish to a wheel creates a wheel with a strong side and a weaker/less strong side. this particular hub will put the higher tensioned spokes on the motordriven/braking left side of the hub/wheel. This may be a good thing, only time will tell?

 

[mickey]

If a spoked wheel is dished, higher tension on the driven side is correct.

 

[Alaskavan]

For my application, I don't want dish. I'll grab one and get back to you with dimensions.