flyinmonkie's chopper build

[flyinmonkie]

Well, it has been ages since I have worked on my bike! And I am still alive! So, I finally have done some work after a week off of real work and some fun. I also had to think long and hard about my rear hub. The one I built didn't really come out true and my wheel wobbles pretty good. I am going to push on until the other hub I ordered from the US arrives in a couple of weeks. I have moved on to the battery box and have it all cut and bent up. I am hoping to get the corners welded, but it is thin aluminum, so I may not be able to find someone cheap enough. We will find out soon.

After I get it sorted and mounted, I will start a lid as well. I may incorporate the charger into the lid. I have also set aside a 36v controller and throttle just in case I'm not happy with the 24v system like I was with my other build. So let the fabricating continue. From here is mounting the battery box and guts, mounting the motor and gear reduction, and sorting the rear wheel. I have included some early pics of the battery box.

FM

 

[AussieJester]

HEEEEY!!! I was just thinking about you yesterday wondering where you had gotten too, good to see you back and progressing...I LOVE the checker plate aluminum, have a bit of that here myself Instead of welding perhaps follow the route i did with my new battery box ie. aluminum angle on the corners, you could simply pop rivet it to the checkerplate box...(check my worklog if your not sure what i mean i just posted pics)

KiM

 

[flyinmonkie]

Hey Kim,

I know what you mean and it is my back up plan. Probably on the inside with a epoxy on the outside to make the edges look clean. I'll check yours out though to see how it looks. I really want a clean look to this one, unlike the last one. It looked good form 10 meters, but up close is was very home made. I should have more progress this weekend on at least parts of the build if not a mostly installed battery box.

FM

 

[flyinmonkie]

Good news Good news!!! I found a guy to weld the battery box and it could be done tomorrow, but I'm not holding my breath. That means this weekend will be a big one on the build scene for me. I'm going to get my rear wheel sorted for sure and start the motor mount. If I get the battery box back, I'll try to get it mounted as well and the guts put in it. Maybe another week and test riding the chopper. We'll see. Depends how motivated I am.

FM

 

[flyinmonkie]

I didn't get my battery box back yet, so I didn't get much done. I am starting to sort out the rear wheel and that will allow me to start the motor mount. I need to make sure it all lines up. I finally have some pictures of my double rear freewheel set up so see below. Basically I have threaded a freewheel onto a cassette body. To recap, the motor will drive the cassette body and large sprocket like a normal bike. The pedals will drive the freewheel, which drives the cassette body. When the motor is turning, the freewheel will freewheel and the pedals and the long chain to them won't turn. This eliminates a freewheel crank and allows me to gear the pedals for the speed I want to pedal at and gear the motor separately at the speed I want the motor at. I think it's all pretty clever, but then again I came up with it. :lol:

This set up would be so simple on a standard rear wheel/tire. You could even use the rear derailleur to give you several gears through the motor and the front derailleur to give several gears while pedaling. We will see how it goes on the chopper bike, and I may have to do an rc version on an downhiller. I get ahead of myself though.

 

[dnmun]

too cool!

how does it spin on the axle? no binding during rotation in the bearings?

this is a great idea, hubs could even be super narrow too if needed or even wider than this. waiting for road tests.

this may be spotted by the motored bike guys too. i see kim is here, bet the idea gets around now. too cool!

 

[flyinmonkie]

Thanks dnmum,

It was one of those ideas that just hits you. I went down the freewheel crank system and built a bike with it. I wasn't real happy with how it turned out and the idea of the freewheel on the hub just smacked me one day as an obvious solution.

As for the extended hub, I hoped the bearings and races would hold it all true when I tightened it up, but that wasn't the case. It runs nice and free with no stiff spots, but not very true. You may be able to compensate on a narrower rim, but then again you wouldn't have to as the hub would stick out past the rim and tire. I don't think I can true the 4 inch wide rim to compensate for the wobbly hub, so I have ordered a slightly narrower, DH hub. It was the widest I could find for a reasonable price. When it comes I will lace it in the rim.

If you were using a standard width rim it would be easy to just replace the hub body, or possibly cut threads on the outside of the hub for the freewheel. Then you are ready to go. The next challenge is getting the motor lined up and both chains to run next to each other without running into each other. Shouldn't be too bad as I haven't built a motor mount yet and should be able to put it where ever I need laterally. Kind of wishing I had the $ for an RC set up for this with one of Matt's drives. It would fit so well between the seat post and the fender, motor and all. Oh well, not this time around. I'll squeeze my currie in there and set up a gear reduction below the lower tube of the frame.

FM

 

[flyinmonkie]

I got the battery box back this week and the welding is fantastic. I will try to mount the box this weekend and start putting the guts in it. I have started designing the motor mount and think I have it sorted in my head. I may make a mock up just see how it looks. I also have to see about clamps to attach it to the frame. Won't be too long now before test rides.

I have attached a couple of pics of the box placement. I'll be making a lid as well after I get everything all sorted and see if the charger will fit in the box.

FM

 

[flyinmonkie]

I now have my motor mount mostly cut out and how it is going to attach to the bike sorted. The motor mounts to the large plate and the angle pieces will be extended to be able to use u-bolts to clamp to the bike frame. The smaller bracket will be extended and be bolted to one of the rear fender mounts. The small plate is for the gear reduction. That will be achieved with a bike hub, maybe 2 if I decide to go with a double reduction. That will make it very easy to change gear ratios if I want. I just have to work out how to hold up that bracket without getting in the way of the pedal chain.

My new hub also showed up today. Check out the size of that axle. I may have to get a longer one made and enlarge my dropouts to fit. This extra big rear wheel has been the biggest problem of this build. But it will be worth it when it's done. Almost rethinking my drive setup for this bike, but going to hang with it. Below are pics of the motor mount and the new hub.

FM

 

[flyinmonkie]

Hello everyone,

Well, I have been quietly tinkering away like the little elves in the shoe shop and things are getting close. My motor and gear reduction mount are almost finished. I have a little shaping to do on the bat box brackets and then it is bolt it together and wire it up. After a lack of motivation, I am getting close enough to be remotivated again.

I'll get some pics of the motor mount soon as I finish it up. I'm going to go with one gear to start with, as it is a single speed bike. After I test out the drive setup, I may look at trying to add a couple of gears for the motor.

FM

 

[deecanio]

HI fm,

the chopper is looking nice 8)
Looking forward to some more pics and the first test runs

Cheers,

D

 

[flyinmonkie]

Thanks D,

Here are the pics finally. I have the motor mount sorted now. The slots in it that are below the frame are going to hold a bike hub or 2 for the gear reduction. I just need to figure out how to hold up the other end. It is very close to the chain from the pedals. I have a bit more shaping to do on the battery box brackets and have to get 1/4 turn fasteners to attach the box to the brackets. I've included a couple of pics of the rear sprocket set up in the bike as well. We're getting closer every week.

FM

 

[marks]

you probably don't want to hear this, but I hate the look of the battery box! Are you sure you can't go to a motorcycle wreckers or something and pick up an old motorcycle fuel tank? You could then cut it somehow so you can get the batteries in there.

 

[Lucky_Hoodlum]

I think it look ok, i think if you paint the battery box same color as frame it could possibly look nicer? i like this double sprocket arrangement on the rear you have going and how you did it nice work

 

[flyinmonkie]

Thanks Lucky,

I'm going to leave the box for some bling, and it is pretty hard to paint aluminum well. I may paint the motor mount black or grey though. I don't want too much bling.

 

[recumpence]

I actually like the look. What may not look right to some people is the fact that the bike itself looks like a motorcycle. So, from a familiarity perspective, the rest should look like a typical mootrcycle as well.

I think it looks fine.

Matt

 

[dnmun]

big blingy, why not flames too, hehe. i think its cool too. wear ankle shields, but you not gonna pedal much i suspect.

 

[EVnewbie]

I love your bike and the dual drive makes a lot of sense,
I plan on something along the lines of your system. I want a one-speed freewheel to get the bike started to conserve on battery power. I was thinking a 34/28/24/20 four speed for my motor. My motor is a Powerpack 36/48V with a 35 amp controller that spins around 3,000 RPM. Four Dewalt 32V packs in parallel provide the juice to a 48 spoke 26" rear wheel.
Were can I get a freewheel to slide on a cassette body? Unlike you, I have the space for the chains and was hoping I could squeeze on 4 gears with a freewheel gear on an 8/9 speed 135mm cassette hub. Is that part something special or a standard BMX type part?
Now to figure out how to get the speed of the motor down. My bike is a Giant Stiletto so it has a mid drive crank axle so I can use a 52T crank on one side to drive the 21T on the other side of the axle. Now I have to figure out how to get the motor speed reduced from 3K to around 750 RPM before I reduce it again with the 52T crank gear. A planetary 4:1 or so would work but my powerpack motor uses a smooth shaft.
Thanks for posting your build, I have another variant in the wings and appreciate any info on gear reduction or freewheels to fit on cassette hubs.

 

[flyinmonkie]

Hey Marks,

Yes the box is very square and kind of bulky. I don't think I could fit 3 12v SLA's in even a Fat Boy tank lol, nor would I want to spend the money for it. The diamond plate was free and the welding cost $25. Hard to beat. I kind of like the look of it personally. I'm not trying to build a motorcycle, or I would have used one. I really just wanted all the space in the frame a chopper gives.

dnum,

We'll see how it preforms, maybe I'll need the flames to make it look like it is going faster. :lol:

Thanks Matt,

I appreciate the compliment from see the workmanship you do. I agree with your comment, that since it looks like a motorcycle, people would expect to see motorcycle parts. I thought if I go to lipo's or something similar in the future with this bike I may try to configure them to look like a V-twin, though. Hard to do with SLA's.

EVnewbie,

If you look back at the beginning of my thread, you will see that the freewheel is the standard part. Well, the hub is as well, it is just an older style hub. It is a uniglide hub, which is older technology and the outside sprockets threaded on. They happen to be the same thread as a freewheel. Examples and pics of the set up are early in the thread, check it out. Talk to the LBS and see what they have laying around, or check ebay. Make sure it is uniglide. You should be able to get at least and 8 speed in one.

Check out this thread http://endless-sphere.com/forums/viewtopic.php?f=28&t=7180 for gear reduction. Matt may be able to make a drive for your motor. You could always use the middle set of sprockets for reduction as well and run a single chain back to the rear wheel form the pedals.

FM

Yes it will be easier with a standard rear wheel as well, instead of this really wide on. I like a challenge though.

 

[marks]

Hey Marks,
Yes the box is very square and kind of bulky. I don't think I could fit 3 12v SLA's in even a Fat Boy tank lol, nor would I want to spend the money for it. The diamond plate was free and the welding cost $25. Hard to beat. I kind of like the look of it personally. I'm not trying to build a motorcycle, or I would have used one. I really just wanted all the space in the frame a chopper gives.

I know where you are coming from of course, plus I didn't rememeber you had SLA's in there - perhaps if you revisit later and put in lion batteries you might consider a motorcycle fuel tank - just look at the variety out there
http://www.justgastanks.com/store/index.php?main_page=index&cPath=65&zenid=km810auu6ece216153vte3ggo4

 

[flyinmonkie]

Again I have been quite for a long time. Well, I have been lurking here between working on my bike. Lots of progress has been made. The motor is fully mounted and the gear reduction brackets are almost totally sorted. It has been test run in the stand to make sure the concept works and nothing rubs this time. It is all good and surprisingly quiet compared to my last bike. Could have to do with the chains not rubbing on anything. :lol:

I should be test ridding within a week or two. I still have to attach the battery box and finalize the right side gear reduction mount. It won't be what you see in the picks below. So I have included an overall pic, and some close ups of the drive system and chain layout.

FM

 

[flyinmonkie]

I am very close to test riding now. I am putting the last touches on the gear reduction mount. I am having some trouble making it strong enough to support the force created by the chain and motor. Basically the end of the reduction that the sprockets are on is moving around under a load so the chain jumps off. I hope to have that sorted tomorrow. I also still need to attach the bat box and set everything up inside it. That shouldn't be too bad though.

I did find that I need to get a half link or a half link chain to get the final drive chain and the pedal chain to be the proper tension at the same time. I thought I had put enough adjustment in the set up, but I have ended up a half a link off again. In the mean time I have taken the pedal chain off to keep testing the motor drive in the stand. I am excited about being able to test ride it soon. This has been a bit of an epic build as I have been very busy with work over the last few months as well.

With all the progress in the RC area, I am already thinking of my next project. Oh to have $ to just play.

FM

 

[Lucky_Hoodlum]

I am very close to test riding now.

I look forward to seeing this wonderful build in action! I wish luck with finishing the rest of the work
off quickly and hassle free

 

[flyinmonkie]

I got the bike complete enough today for a test ride! I still have a lot of small things to do for it to be complete and become my commuter, but I did ride it today. It was very smooth and quieter than I expected. I am very happy with what I have done so far. It accelerates pretty good compared to my last bike and I have gotten it up to 22k/hr so far. A little slower than the 30k/hr of my last build, but I can change the gearing if I need to. Over all it is a lot smoother and feels better than my last bike. The chain popped off a couple of times, but I am using an old chain and it has at least one stiff link. I also need to stiffen up one side of the gear reduction bracket. Bur over all a good test ride.

FM

 

[dnmun]

neat, that's the bracket with the diamond plate over on the right side?