flyinmonkie's chopper build

[flyinmonkie]

dnmun,

Yup that's right, the diamond plate bracket. It is a lot smaller now and attached to the chain guard, which is not in the picture above. The area where the hub attaches has a thicker plate of aluminum behind it. The chain guard also has a thicker strip of aluminum running from the bracket the the rear attachment point for it. It helps a lot, but there is still a fair amount of movement as the bracket is only attached at the top and there is a lot of leverage on it when you open the throttle quickly. I will most likely run a bracket to the frame at at the bottom of the bracket as well. This will stiffen up the bracket and allow me to run a chain guide for the motor drive chain to keep the chain out of the way of the rear brake. Little things, it's always the little things. Overall it is going well and is better than my first bike.

FM

 

[flyinmonkie]

Only some final touches and some paint left now. I have my drive sorted and all my mounts done. I need to add a tensioner or a block of hard plastic to take up the tension on the drive chain. Then I can put the pedal chain on as well. I also have to sort out how the cables will go into the box, but these are minor details compared what I've done already. I'm also going to paint all the motor brackets flat black, with the exception of the small piece of diamond plate holding the gear reduction.

I have test ridden it some more and with 24 volts of SLA's I get pretty good acceleration and a top speed of 22k/hr. I haven't run the bats down yet so I don't know how far I can go yet. That will be coming soon. I am very happy with this build so far and am looking forward to commuting on it. It is solid, smooth, and quite. Most of the noise is coming from motor whine and not the chains.

FM

 

[flyinmonkie]

Well, I have my bike fully functional now and have ridden it to work and back. Of course everyone there had to have a go. So far so good. The only problem so far is my gear reduction hub slipping. I'm not totally surprised as it is just a quick release bike hub in horizontal slots. I've heard a QR can hold a rear wheel on a single speed so I figured if I did it up really tight it'd be all good. It may have been a few of the people that rode it hitting the throttle a little hard. Not a bad safety measure if it is. Keeps from breaking chains. I'll tighten it up a bit more tomorrow and give a few more days before I decide if it needs to be changed. I also am working out a small chain guide/tensioner for the final motor drive chain.

Basically I have the drive chain running over a bolt with an aluminum sleeve and a PVC sleeve over that before the drive sprocket. It takes up a bit of slack in the chain due to the pedal chain and the motor chain being half a link out, and keeps the chain out of the way of the rear brake. I'll post pics soon. I know it takes a bit of wrap off the drive sprocket and being on top is not ideal, but is allows room for the rear brake. I'm not sure how long the PVC will last and may have to come up with something that is harder or a roller on a bearing. The space is very limited though.

Over all I am very pleased. It tops out at 25K/hr on the flats. It slows down quite a bite on a small incline, but you can pedal to help out. I don't know how far it will go on a charge yet, but I will test that soon. Just a few cosmetic things to clean up and I'm set. I'll ride it as is for a while and then decide if I up it to 36 volts as well.

FM

 

[GGoodrum]

Interesting. I'd like to see more pics of the your reduction setup. Always looking for new ideas.

On my new Cyclone setup, with dual chains to the rear, I had to route the pedal chain around the jackshaft drive sprocket, due to clearance issues, and that caused problems with trying to get the two chains tensioned properly, I ended up using one of those deraillur hanger-mounted spring-loaded tensioners, used for singlespped conversions. Works pretty well. Here's what it looks like:

 

[flyinmonkie]

Hey GGoodrum,

Nice, I like it. How is it with the tensioner on the top? Is the front one fixed so it can not move up and down? I thought about using the same tensioner, but I figured the motor would just pull it down whne under power if it was on the top side of the chain line. Yes the two chains to two different places is difficult to get the tension right on both. My pedal chain is a little on the tight side, but it is good so far. Will be interesting after they stretch a little. Half links or a tensioner on the pedal chain is the way to go.

You are still using a freewheeling crank, yes? Another way to achieve the same set up with out running two freewheels or a freewheel on a cassette at the rear wheel, is to add another freewheel at the gear reduction and run the pedal chain to it. It would give a shorter pedal chain run, some more choice in gearing for the pedals, and eliminate the freewheel crank and one chain turning when under motor power.

I'm away for the next two days, but I'll get some pics of the gear reduction and tensioner up at the weekend. I'll also work on a vid.

FM

 

[GGoodrum]

The tensioner works quite well, even on top, but I'm only using it on the pedal chain. It moves up slightly under load, but it actually pulls the chain away from the stay, which is good. On the motor drive, the chain is all half-links, which is very handy.

I' agree, it would be better to have another FW at the hub, instead of on the crank, but I haven't yet figured out an easy way to do this on a Nexus hub, with its single 3-splined cog. One problem is that the ideally, you'd like the added freewheel to be the one the motor drives, as it could then be a high-quality one, like the ENO, but then it would need to be inside of the cog driven by the pedals, assuming you wanted to use a larger sprocket, but a standard freewheel won't fit over the front end of the Nexus hub. What's really needed, to at least use a standard FW for the pedals, is a piece of threaded pipe that screws into the FW, and then is welded to a standard Nexus cog, which could then be bolted to an adapter that can hold a larger chainring. I'm still noodling on this.

-- Gary

 

[recumpence]

I agree, it looks very good Gary.

Double chains can be a little finicky to setup. But, once setup, they work very well and solve certain problems.

Gotta love those Trials chains. :wink:

Matt

 

[flyinmonkie]

Gary,

I thought the drive chain was half links. I have a bit of trouble finding one here in New Zealand. Great place to live, but you don't get all the cool options of a larger country with a bigger population. I guess that has developed the Kiwi ingenuity, lol.

Keep us posted on getting 2 sprockets and a freewheel on a nexus hub. I'm keen to run a setup like that. As Aussie Jester posted early in this thread, you can run the pedals to the the jack shaft for the 1st or second stage reduction with a freewheel. That of course is if you have the room on your frame to do that. I really like the simplicity and separation of drive systems using 2 chains and no freewheeling crank.

As far as how the bike is going... I went for a long ride the other day and ended up pedaling most of it. The chain came off the front sprocket and got stuck between the 2 sprockets and under the head of the bolts I used on the sprockets. I am going to replace these with a pan headed bolt so the chain won't get stuck if it happens again. On the up side, it actually pedals quite nicely.

I'll get some close up picks of the gear reduction and chain tensioner I have set up today and post them this afternoon. While I am doing that, I'll be putting final touches on the connections and battery box and cleaning up the appearance.

FM

 

[flyinmonkie]

Here are the pics of the drive train and gear reduction set up I am using. The quick release rear bike hub has slipped a couple of times, but I am going to see if I can get it tight enough to stay put. If not, I'll go to a bolt on axle and if I have to BMX chain tensioners to hold it in place.

FM

 

[GGoodrum]

Very clever setup. Did you have to do anything special to get the pedal chain to clear?

On mine, I blew the Cyclone controller (it didn't like simply reversing two phase wires... ), so I backed up and have decided to skip the Cyclone test, and go straight into a 3210 setup. One change I just did has simplified the setup significantly. Originally, I couldn't use one of Matt's freewheel adapters to hold the 12T track cog on the reduction shaft, as this adapter doesn't have a shoulder. It is designed to screw into a freewheel, period. I had to use an adapter I got from BikepartsUSA.com, which has a shoulder, but it is huge. What I found, though is by using a standard bottom bracket lockring, I can use Matt's much narrower adapter with the 12T cog, and now the pedal chain easily clears the shaft/adapter. This means I don't need to route the pedal chain around the adapter anymore. I've also moved the tensioner to the bottom.

-- Gary

 

[flyinmonkie]

Nothing special to get the pedal chain to clear. The bottom bracket on this bike is huge. I haven't measured it, but it is seriously wide. That with the 170mm rear hub, there was tons of room to run the 2 chains side by side. The chain lines are nearly perfectly straight on both the motor and the pedals.

Sounds like you have simplified yours greatly. Yes, bottom brackets and freewheels have the same thread. Comes in very handy in many ways.

Tomorrow, I'll be sorting out a few little things with the battery box and and putting a some final touches on. I think I'll ride it as is for awhile at 24v and get any bugs out of the drivetrain and then probably jump it up to 36v and see what happens. Has anyone overvolted a currie scooter motor before? I have a 36v controller and throttle, so it will just be the motor.

FM

 

[flyinmonkie]

I have done an endurance test now by ridding to work and back. I got 12ks out of the batteries before they started to drop off. I am very pleased about that. I also topped out at 27k/hr, and mostly ran at 25k/hr. I had no mechanical or electrical issues either.

Well, though I am pleased with how the bike has turned out, I have already upgraded it to 36v. I had a controller and throttle because I had the upgrade in mind when I started. After a short test ride tonight when I finished, I now have much better acceleration and topped out at 36k/hr. What a big difference between 25k/hr and 36k/hr! Tomorrow I'll to some more testing to see just what it can do with 36v. I think my gear reduction hub is moving under the power, but that should be easily fixed with a bolt on axle vs a quick release axle. Also, the chain seams to pop off the rear sprocket, so the rear wheel may not be perfectly straight in the drop outs. I'll check that tomorrow too. Let the fun really begin now.

I can't imagine 6kw on a BMX, like Matt's PK!

FM

 

[recumpence]

I can't imagine 6kw on a BMX, like Matt's PK!

FM

8KW. :wink:


It sounds like the build is going very well indeed. I think the performance at 36 volts should be good for the long haul. The performance you were getting on 24 volts seems anemic.

Matt

 

[flyinmonkie]

Nice Matt,

An RC build is in the future for me, but not anytime too soon. Need to save up a little.

Yup 24v was pretty tame. Not too bad on acceleration and top speed for a single speed and currie scooter motor, but 36v is pretty good so far. I'll stick with the SLA's for now, byt might upgrade to NiMh or LiPo eventually. Remember it is a big heavy steal frame chopper with 3 12v 18amh SLA's in it. I'm just happy it all works as planned. It actually feels and handles really well. It is solid to ride and feels like a manufactured product, not a home made tinker toy you have to be careful with. that was the plan.

I still need to finish the battery box lid. I also have to modify the box so I can get at all the plugs with the 3 batteries in it. Not much room left in there now.

FM

PS Happy b-day Matt

 

[recumpence]

Thanks!

I got a gift card for $50. So, I am off to Best Buy to pick up some sort of technical documentary (maybe something on NASA). My wife gave me a little something too.......... :wink:

Anyway, I am glad your build is going well. I hate that "Home-Brew" thing like you mentioned that you have to be very careful of-------- "Do not turn left while accellarating with your right knee hitting the frame or the thing shorts out......"
That kind of thing. I want to be able to just give my bike to someone with a simple explanation of how it works and off they go without worrying that they did not do everything just perfect, or with a fear that the slightest bump will destroy the bike.

Matt

 

[flyinmonkie]

No worries Matt, sounds like a good b-day.

Yup that's the idea, anybody should be able to ride my bike and they nor I have to worry about it.

I don't have to worry about that at the moment though. I went out to do a good test run with the 36v set up today. It was going quite well, then the controller was loosing sync with the motor. It happened mostly at low speeds and would sort out once I was moving. I went to the LBS to show the guys there why I had been accumulating so many odd parts. At the second ride it just stopped working.

The main fuse had blown, so I pedaled home and went to replace the fuse. Big spark, motor spooled up and the fuse blew. I made sure everything was ok and unhooked the batteries and plugged a fuse in. I then rehooked up the batteries and same thing, motor spools like it WOT and the fuse blows in less than a second, whether the throttle is hooked up or not. I took it all apart and pulled apart the controller, everything inside looked fine. A little hard to tell as it was all covered in silicone, but nothing was melted or burned, or smelled burned. I didn't see any magic smoke let out, other than the fuse. Not sure if the controller is toast now or if it is in the motor. It is a currie controller and motor.

Any ideas?

FM

 

[flyinmonkie]

Hey guys,

Well, this project is not dead. I went back to the states for a few weeks on holiday. I'm back now and am starting a new business in the next month (not EV related), so I have been pretty busy.

So a quick update, my controller or throttle crapped out after going to 36v. Doesn't make too much sense as I used a 36v controller and compatible throttle. Maybe I just got a bunk one. Anyway, when you plug it all together, the motor spins up like mad and with in less than a sec the fuse blows. The first fuse to blow was 40a, so it is drawing like mad under no load. I opened up the controller, but it did not look or smell burnt, and I never saw any magic smoke released. The entire controller guts have been covered with silicone, I assume to water proof it, so I can't really see anything. It is a currie controller and currie motor and currie throttle. I am using 12v 18ahr SLA batteries.

So on to a new controller that I picked up while I was in the States. Turns out I needed a different throttle for the controller. Couldn't remember which one I got. Oh well, I am now waiting for a throttle as they are back ordered and should see it in a couple of weeks. Then time to try again. My new controller is a 30a, so it is a little step up form the 25a controller I had. (I'm sure pulling 40a through it before wasn't good, got the fuse size wrong as I was guessing when I put the first one in). I hope to be up and running again as 36v was much closer to what I was shooting for. I'll keep you posted.

FM

 

[deecanio]

Hi fm,

hope the new controller and throttle work out ok, the build is looking nice and glad your getting some rides in to0
get some vids done when your back on the road, nothing like them to show how it goes.

D

 

[flyinmonkie]

Thanks D,

That's the plan. the throttle shipped in the US today. Should be on it's way to NZ early next week. Looking forward to it as it is warming up and drying out here.

 

[flyinmonkie]

Hey guys,

Well I have been away for quite a while now. I have been checking in occasionally. Lots happening and it's exciting.

My build has been put on hold, as I have started a new business and moved to run it, all at the same time. The chopper is still happening, but hasn't been moved to my new place yet. Shouldn't be too long now though. When I get it here, I just have to wire the new controller in and swap out the throttle. Then I can test 36v, which I will need now that I live in a not so flat area.

That will probably prompt another build with gears. I need to finish the chopper off and ride it for a while first though. I'll post some news as soon as there is some, along with some video of the chopper.

FM

 

[AussieJester]

along with some video of the chopper.

FM

Look forward to the video great to see your back...hope your business is going well too mate...Didn't move to OZ did you
rest of the Kiwis seem to be here wouldnt be too many left in NZ would there heheee...

KiM

 

[GGoodrum]

Didn't move to OZ did you
rest of the Kiwis seem to be here wouldnt be too many left in NZ would there heheee...

That'll make the sheep happier...

 

[flyinmonkie]

Aussie, yeah a bit of an invasion, I guess I'm replacing some of them as I'm from the States. lol Nope, I moved further south. Down in Wanaka now. Not sure where I am going to get parts from other than online. Little town in the mountains now. Great views though.

GGoodrum, lol, well... the aussie sheep are scared now.

 

[GGoodrum]

Aussie, yeah a bit of an invasion, I guess I'm replacing some of them as I'm from the States. lol Nope, I moved further south. Down in Wanaka now. Not sure where I am going to get parts from other than online. Little town in the mountains now. Great views though.

GGoodrum, lol, well... the aussie sheep are scared now.

I did some consulting work for the Ministry of Defence, back around 8 or 9 years ago, and spent about 3 months down there. My partner was a fly fishing nut, and NZ has some of the best fly fishing in the world. Each weekend he'd drag me all over both the North and South Islands. The problem was he was very stingy with his fly fishing tips, so it was two months before I caught my first fish. He got great pleasure in watching me struggle, while he was catching big lunkers, seemingly at will. Once he actually hooked one that was passing between my legs. :lol: Finally the local guide who ran a tackle shop near Lake Taupo took pity on me, so she gave me a few of her "special" flies, that she didn't share with my partner, and spent some time with me to show me what I was doing wrong (not waiting long enough before setting the hook...), so by the time we finished the project, I was doing pretty well. My partner thought I just lucked into figuring it out, and I didn't tell him what she did for me until we were on the plane going home. He was pissed.

Anyway, NZ is a beautiful place, and quite different from OZ-land. It is because it originally was part of Antartica, while Australia broke off of Asia. Parts of the South Island have these magnificent fiords, and you'd think you were in Norway. Lake Taupo, on the North Island, reminds me of Lake Tahoe, up in northern California, which is about as picturesque as it gets. Another amazing factoid I learned is that NZ has no poisonous snakes, spiders or insects. In Australia you'd be hard pressed to find a species that wasn't poisonous. :lol: Don't get me wrong, I love Australia, and have actually spent a lot more time there, over the years, than I have in NZ, but for different reasons. For one thing, the women in OZ are much better looking, and are much more inclined to peel off their kit at places like Bondi, etc.. :lol:

Okay, back to the regularly scheduled programming... :wink:

 

[flyinmonkie]

Gary,

The world gets smaller every day, huh? I do a bit a of fly fishing and I'm looking forward to actually doing some serious stuff, now that I live int he middle of some of th best in NZ. I have been here for 4 years or so now and have seen more of NZ than most Kiwi's I have met. You're right, it is an amazing place with such variety, and all so close. I enjoy the culture with it's laid back attitude. it reminds me of the Midwest in the US when I was growing up.

OZ is fantastic as well, and you have it spot on about the women. I've up and down the east coast and in Tazzy, but want to get to the centre and around the bottom to Perth sometime. Amazing climbing in Arapps as well.

Clay