Use a long flat blade screwdriver. I bet you can just catch the inner edge of the bearing or the race from down the axle tube. Hit the screw driver handle with a hammer and drive the outer race out. you will want to drive it straight out so don't just drive it out in one spot. Don't worry if you bung up the ID or that ledge a little that stops the bearing. As long as it's 80% there, it will work just fine. From the end of the axle opening, if you file down the edge of the screwdriver to a fairly sharp and curved edge, I bet you can wedge it under the bearing race with the hammer in several places to get it moving. I can guarantee you that if I had that wheel in my possession that I could get that outer bearing race removed and still be able to use the wheel afterwards.
Since you have a micrometer, measure those 3 bolt holes and the OD of that lip. You will need the hole spacing and that lip OD to get an adapter made that will fit your wheel. Contact Michael (LIghtingRods) and ask him to make you an adapter.
There are two things to think about regarding free wheels. Do I want regen or do I want to coast freely. You can't have both. I want the extra run time I get from regen so I don't use a freewheel anymore. Once I switched over to the new wheels, that eliminated the ability to have a freewheel anyway. The WI freewheel is stellar. I have several cheap Chinese freewheels...they are crap. I would only recommend using the WI freewheel. If you look through my Currie thread, you can see that the back wheel has freewheel threads. I took a fixed bike sprocket and drilled it as an adapter for LR's KART adapter. I just don't need or want a freewheel anymore. Regen is better IMHO. On your wheel, you have no threaded section where a freewheel can be screwed on so you are going to use a fixed wheel sprocket no matter what. You probably don't have sufficient width between your drop outs for a freewheel to fit anyway.
This is the original back wheel from my blue scooter. That threaded section is where the freewheel threads on.
The big block is 142mm wide from bolt to bolt. That means across two opposite ears that hold the whole motor together. In the below picture and looking at the black cover, there are two ears for larger bolts. They are 8mm. Place them down and use them and those three other 6mm bolt holes to mount the motor. You can also use the long bolts that hold the whole motor together to attach a bracket for support of the back end of the motor. That's what LR does. You measured 124mm. Put the wheel axles as far back in the drop outs as you can and see how much space you have. If you don't already have axle tensioners, you will want to get a set to hold the wheel from sliding forward.
3/4" ID is pretty standard for KART sprockets. Asusa Engineering is where LR gets them from, but they don't like dealing with small purchases so they may not sell you a single driver sprocket.
If I remember correctly, there are two different sized keyways on my blue scooter. I'm not sure if that is still true for motors that LR sells now or not. Anyway, they are 3/16" and 4mm. I think the 4mm is on the motor shaft and the 3/16" one is on the driver. I haven't tried putting an adapter or driver on my opened up big block yet so I don't know what the two keyways are now. Regardless, if you get the big block, just talk to Michael about that stuff and he will get you the correct parts. LightningRods only makes excellent parts and the big block is no different. His mid drive kits are 100% legit and well made. He doesn't skimp on quality EVER...unlike the bafang BBSHD kits which are pure crap and way over rated. The big block is sold as a 3000 watt motor, but I know for a fact that it will do lots more and not run hot. LR undersells everything he does or makes. Other guys...well they want to sell crap and over rate it excessively.
20S...on the big block on this tiny scooter...well it's going to be fast and quite powerful...probably 50mph or more and you will out accelerate all the cars. I don't know the dimensions of your battery box, but that will directly determine the amount of batteries you can put in the scooter. At 20S I draw 40-60 amps while accelerating hard. 20 cells takes up a lot of space and whatever cell count you go with, it will need to be able to deliver 60 amps continuously...if not more. Higher voltage means more cells to make that happen.
Regarding LIPOs vs LIONs...
LIPOs are cheaper for the same amount of mah than are LION. LIPO packs tend to deliver loads of current for a 1P pack while LION needs many cells in parallel to get the same current delivery. LIPOs have fairly short life spans...about 1/3rd as long as LION. It's not unusual for a LIPO pack to reach 50% of it's life in 50 charge cycles. Once LIPO cells start dropping off they lose capacity quickly. LIPO as a result actually costs a good bit more than LION in the long run. You will get close to 3X more charge cycles out of LION than you will LIPO. Also, if you build two packs...one LIPO and one LION and both have the same voltage and mAh, the LION pack will probably be smaller and lighter. I use LIPO for things, but LION is far better. I have a spot welder and welding supplies. If you are in the USA, perhaps you can buy the LION cells and have them sent to me and I will weld up the pack for you. Just about any battery pack maker can do that for you too. You just need to give them the dimensions it will fit in, cell type, voltage and capacity and they can get it made for you.
You will want a BMS for your battery pack. We can talk about that later.
aethyr said:
EGod,
Thanks for your input!
1) I need at least a new rear wheel because the outer shell/ring of the bears are stuck inside the wheel bore. The actual bearings/inner ring was blown out ages ago and that outer ring is oxidized in there and I simply can't remove it. If you have any suggestions on how I might remove that, then I could keep the wheel.
Below is a pic of the side of the wheel with the outer bearing ring/shell stuck.
The other side had an intact bearing I was able to remove, as you can see, it doesn't have that outer ring. It does have a stop to keep the bearing in place. That also makes it impossible for me to push out the stuck outer ring from the other side because the bearing stop blocks access to it.
Below are pics of my rear housing. I measure about 124mm from frame to wheel, depending on where I lockdown the axel to the frame. Pay no attention to the caliper measurements in the pic - it's wrong. How large is the big block?
The 12mm to 3/4 is perfect! So I'm assuming that 3/4" bore is standard for #219 motor sprockets? What size is the keyway?
I plan to run at 20s LiPOs because they're cheap. Although I probably should just bite the bullet and try my hand building my own pack. I remember you mentioned you had a good source for 18650s? And what BMS would you recommend?
I'm using this
http://toddy616.blogspot.com/2013/07/electric-skateboard-calculator.html to determine my drive ratios. My tires are 10" diameter. I figure with the Big Block I can run 2.5:1 or so to get me to 50mph at 20s with 10" tires.
That link for the adapter shows it as a freewheel adapter. I forgot to mention I would like a freewheel as well. I think I remember you recommending the White Industries freewheel. How does the freewheel, sprocket and wheel all mate together?