Cyclone 3000W Diamondback Aluminum custom build picture thread.

[Jim Day]

I guess I should start by telling you how I got into this......

I'm an artist/sculptor/custom fabricator with a shop in L.A. I concentrate on one offs, or one of a kind problem solving. Clients come to me with an idea of something they want to make, but that they can't figure out how to build, and I make the thing, often coming up with a unique process to do it. I can fab in variety of materials but what I really like is metal and one of my favorite materials is aluminum which I both TIG and MIG. I'm one of those crazy/lucky people that kind of does exactly what they are supposed to do. I build things for money and when I get free time I build my own things for fun, or make things for my friends. In this case I'm building for my freind Gary so it's really kind of a collaboration. Gary is a hunter. I'm not talking about a guy who wears orange gear and rides around in a truck looking for something to shoot at. I'm talking more a mountain man who goes out into the wilderness for weeks at a time miles away from the nearest roads or help, and then packs out meat when he's done. He doesn't just want a electric bike, he wants a mule to get him out to the wilderness and back extending his range. So this build has a very specific purpose. Kind of a dual sport motorized mountain bike. I've never messed with electric bikes before but I'm good with power and have played around with bikes in general. In L.A. there is a art bike scene where people build crazy bicycles then ride them around at huge events. One of the main co-ops used to rent a space next to me and they got me into it. Since I weld aluminum I get to play with aluminum frames that no-one else can work on, so I'm pretty used to playing with aluminum bikes with various funky configurations.


I also dual sport motorcycle mods. My current build is a rally style dirt bike for vintage offroad racing.


So basically there is nothing more interesting to me then inventing my own suspensions or doing frame mods.

When Gary came to me with the idea of his electric bike mule I initially wanted to design him an electric motorcycle with my own suspension design from the frame up. He wanted a bike that still could pass as a touring mountain bike at least from distance, and wanted to play with a standard build kit. So it was a compromise. It needed to be built with the standard stuff but it needed to get him out there, and not fail him if he dropped it or crashed back in the back country. I like the idea of the mid motor but was afraid he'd destroy the gear motor under the frame mount on rocks. So we bought a kit from Luna, but I moved the motor up where I could protect it.

Madness ensued

Part 1 Aluminum.
Gary brought by his donor Diamond back and like with all the best bike mods this started with a sawsall.


The idea here was to replace the downtube with twin tubes like a MX motorcycle frame. I'd connect to the front at the headtube, and run the rear down to the bottom bracket moving the connection slightly forward to make room for the motor. Since I was using only 6011 T6 aluminum and MIG welding it (lower heat exchange) I could weld it up without blowing the temper or having to heat treat it afterwards. The first thing was to get the forward transition to look right, which meant I had to bend the tubes. T6 can't be bent cold untreated you have to heat it to temporarily remove the temper. I always do this on the stove. You start by marking the tubes with a black marker then heat them.




When the black marker has transitions from dark to brownish gold. That metal is 350+ or temporarily T4 (it re-hardens with time) so it's ready to bend. This is the oldest trick in the book, but I still think it's cool every time I do it.

So I threw that metal in my bender, put a radius in it then cut the ends to make a even transition to the head tube.




Once that was fitted I cleaned up the bottom bracket and then welded the tubes to the front of it then added additional bracing.


Here you can see the added back plate stiffener for the motor mounts.



I considered making my own motor mounts but used theirs out of expediency. As you can see I beefed them up a bit.




With the added bash plates you can see where this is going.












So that is the basic frame, weighing in at mighty 6 pounds.

Part 2 Dubious additions.

Next step was to add the side bash plates to protect the motor and my initial try at a battery mount.


The idea there was the battery would twist in and out and be held by a removable bracket in the front. Unfortunately the battery got stuck. While fighting with it I decided I wanted to cover the battery with metal to protect it anyway so that mount was scrapped though the bash plates remain.

Part 3 the war of the bottom bracket.

I hate to bash people's stuff, but I'll be straight up I had some real problems with the standard cyclone kits ]replacement tapered 68-83mm BB. The right side tried to cross thread every single time I attempted put it in. Both cups were shallow and the left cup was also not deep enough to correctly catch the bearing, and the bearing spacing was not correct to line up the crank arms properly with the motor. Just not cool. The first mod I made was a bearing spacer to get the bearing over.


Even with the bearing moved over the cup still would not thread. After fighting with it the better part of a afternoon, and re-cutting the threads with a die, I gave up and threw a pair of used Shimano cups on the lathe and machined them to the exact tolerances I needed.


That threaded up nice fine but once in place I realized the right cyclone kit bearing was bad. It had a bind or catch in it, so I took the whole thing back apart and replaced the right bearing with a Shimano sealed bearing of the same size.

All Shimano goodness right there.

Since the right side gets the most force and the left bearing seemed fine I just used the left bearing that came with the BB on that side. Hopefully that won't come back to haunt me.


This got me the exact alignment I needed one the crank and drive chain rings.


The crank arms had the proper spacing as well.




Part 4 General refinements and the battery and controller mounts.

Now I needed a way to hold the battery in place, so I modified the first bracket I made.

Chain ring side bash plate, rear battery support, and controller position.


Down tube Bash plate right side full length.


Motor bash plate left side.


Bash plate and down tube left (note the opening for power cable routeing in front of the forward battery stop, all wires from the front will run under the battery.)

Here you can see how the twin tubes line up compared to the original.


Here's the battery position with my initial enclosure (there are still some minor refinements I'll be doing to the enclosure)


As you can see the down tube has been converted twin arm motocross type to give him more protection but also more space for the battery and motor. It also allows space under the battery for routing excess wiring. Best of all it keeps the frames original size with the profile of the frame the remaining same. (stealth factor) The new structure connects at the two fixed (non flexible) points of the frame, but leaves the rest of the frame to flex under load like a normal frame. So the bike itself still feels like a normal bike even with it's gear and power load.


Part 5 ride tests no power.

At this point I decided to assemble it all and check the ride. My take was that if it did not ride well, I needed to know as soon as possible. We are talking the battery and motor in there for weight but not wired, with the rear derailleur installed and working, and the brakes are set up and adjusted. I first tried it with only the motor and it felt like a decent well balanced mountain bike. I could ride it like that all day and never think twice about it being anything but a normal bike. The battery increased the weight, and it alters the center of gravity forward but the bike still rides decent. Straight up no bullshit assessment. Bike rides a lot better without power then I thought it would.

Assembled pics.




Here's a couple of pics my neighbor took of my while test riding it. They are good for scale but you can also see how relaxed I am riding it. Even in tight circles in a confined space behind my shop it felt good. Great low speed stability, bike felt great, very comfortable to me.




Part 6 Wiring the controller.

So I could not find much information about wiring the controller, but gave it a hard look over and basically figured out what I needed. I kinda decided to remove everything else, but then was afraid to do it

Friday after a long night I took the plunge. I cut off all the wires that I did not need, and heat shrinked them clear with their respective labels inside the controller for further reference.


I then spliced in a new power feed wire for one of the connectors so I could solder it in inside the box.


Connected that wire in when I wired the new power leads, with XT90 connectors.


....and this is the result.



Now there is a mistake there. I used a quick connect for the blue wire underestimating the power that was running through it. It functions but it's overheats. What I really need is a single XT90 connector to solder in there (fixed that last night).

Here's everything in the bike.




I'll post some better pictures later



Part 6 first powered ride test.

Gary showed up a on Saturday and I hooked everything up. Amazingly it all worked the first time. I swear the last thing I said before I plugged it in was: "How much are those control units"

Road good.

I was pretty impressed. Very fast but very stable even I'd say comfortable at all speeds.

That's not even it's top speed. I was testing it with the 46 chain ring forward, and in the middle of a 11/34 mountain bike cassette rear so probably about a 18 rear. I later made some faster runs with higher gears but started getting nervous when the speeds topped well over 40+. The bike felt fine but I didn't feel comfortable riding at those speeds on something I just built without a helmet. Since I ride both motorcycles and bikes it's almost too accessible. It's not really a bike anymore but does not feel like a motorcycle, it's something in between. What really surprised me was the high speed stopping distance. The disc brakes had plenty of grab but the issue was traction. It's under sixty pounds so it wants to skid when you brake hard. I'm just not used to braking a bicycle at those speeds. It's probably going to eat tires.

So that is where it's at now. I still have a few refinements to do, and it's going to get painted, so I'll be adding more later

[JPLabs]

That's a heck of a post. It's nice to see some of the finer details...sequence of welds, fitment, metal thicknesses, and such. It all looks great.

You seem to have a solid understanding of working with aluminum and it's properties. So, a question about that, if you don't mind:

You had mentioned, I think, that welding that 6061 (?) alloy with MIG worked well without ruining the material properties, due to lower heat. Do you mean that TIG really isn't suitable, unless you can heat treat again after welding? I have both MIG and TIG, but prefer TIG and have a better setup for Al with that. I haven't tried a bike frame (or anything that highly stressed and structurally tuned, really) but would like to.

Do you think I would be compromising strength a lot more if I TIG an aluminum frame instead of MIG?

[Jim Day]

That's a heck of a post. It's nice to see some of the finer details...sequence of welds, fitment, metal thicknesses, and such. It all looks great. You seem to have a solid understanding of working with aluminum and it's properties. So, a question about that, if you don't mind: You had mentioned, I think, that welding that 6061 (?) alloy with MIG worked well without ruining the material properties, due to lower heat. Do you mean that TIG really isn't suitable, unless you can heat treat again after welding? I have both MIG and TIG, but prefer TIG and have a better setup for Al with that. I haven't tried a bike frame (or anything that highly stressed and structurally tuned, really) but would like to. Do you think I would be compromising strength a lot more if I TIG an aluminum frame instead of MIG?

Here's what people imagine when they think of welded aluminum.


TIG welded, hot, clean and pretty.

I know you know this but TIG works with a torch. A tungsten electrode in a field of argon creates a AC electric arc flame that melts the metal. When the metal melts if forms a puddle, and once you have the puddle you stick a filler rod in there and create a raised disc or "dime", so each ring you see is made one at a time by dropping in a drop of metal that you get by sticking the filler rod into the argon flame. Since the flame is going all the time it really heats up the surrounding metal it's like having a torch on it the full time, and it takes time to lay down that type of weld unless you are really good at it.

Me personally at best I can do about a dime a second but it usually takes me longer then that, and at roughly ten dimes per inch that time and heat transfer adds up. Let's say it takes me roughly 20 seconds per inch at a low heat to make that type of weld, and a full time 40 hour a week welder might be able to do it 3 times that fast, it's still going to be a lot of heat transfer.

MIG means Motorized Inert Gas. There is no tungsten, no flame, no filler rod, no puddle, no drips of metal. The way it works is you have a wire feed gun with a nozzle that blows out argon and feeds out a DC charged wire that melts when it hits the parent metal and burns in. If it's melting and dripping you are welding too slow.

Here's a MIG weld from my frame project:

As you can see it's not even remotely the same. Someone who doesn't know what they are looking at might think that is a really ugly poorly executed TIG weld, but it's actually a really specific type of MIG weld that I setup specifically for this task. I'm running a spoolgun with .035 wire at a high amperage and very high wire feed speed. This allows the weld to get maximum penetration with the minimum heat transfer. That two inch weld took all of two seconds, roughly 1/10th the time it would of taken to tig . It's 100% penetration welded completely through but the metal surrounding it never got hot enough to change it's temper.

You do not have to take my word for that. Above in the initial post I talked about how you can bend 6061 T6 by heating it up to 350 degrees, just hot enough to temporarily relax it's temper for bending, but not high enough to effect it's temper long term. This is a known industry proven way to bend 6061 T6, but retain it's strength long term. I also showed how you can easily gauge it's temp with using a common sharpy. That the color of the sharpy changes when you heat it up hot enough to bend, an old good trick I learned from someone who welded for Boeing.

Here are two pieces of 6061 T6 marked with a sharpy.


Here's the same two pieces welded together 100% through at the exact same settings I was using for the frame.

Here you can see the size of the piece and that it was welded in one single pass with no starts or stops.

That weld took me all of two seconds to make, and it's just barely turning the last marks brown on the ends. So probably well under 350 degrees.

If the metal got really hot it would of burned the sharpy away, and it would of got that hot with a TIG. If it went up to standard bending temp, a temp warm enough to allow temporary bending it would of turned brown and looked like this:

You can clearly see they did not even go brown, they are still black which means the metals temper was completely unaffected by the welding. Straight up the metal I heated on my stove for bending got hotter, which means that welded metal is still T6 temper.

Lets do some testing.

I went over to my vice and put the now welded 6061 into it and tried to bend it 90 degrees. It got a little bunged up because it slipped out of the vice the first tries (hard stuff).

Bend one: Did not snap through but it shows fatigue evenly across the piece. The weld snapped but it was thicker so it deformed more. You might note that with a TIG the weld would have a lower temper then the parent metal and not cracked at all, but not the case here, because it's MIG'd not TIG'd.

The rest of the cracking is consistent with a standard piece of flat bar 1/8 6061 T6 Aluminum. With rod or tube it will often snap first try but flats you can usually get a bend or two into them before they break.

Bend two: It's almost failed with only the ends still holding on. That is really interesting in itself.

If the welding had changed the temper the metal farthest away from the weld would have the highest temper and crack first. If the metal had heated to 350 it would of bent and not cracked. This piece is cracking like stock right off the shelf 6061 T6.

Bend three: Well it never happened. I just broke it off with my fingers.

As you can see the materiel was unaffected by the welding and snapped evenly right across the weld like standard 6061 T6. I really thought the marker was going to go brown, and the metal would drop to T4 long enough to bend it, but it actually maintained a T6 hardness the whole time. Basically this test it confirms everything I thought about this process.

So in light of my new data...LOL

I wouldn't do anything like this with a TIG unless I could heat treat it afterwards. MIG is the way to go. You want to run it hot and fast, and if you do it right you won't damage the temper of the 6061 T6.

[JPLabs]

Thanks! That was great. Not only did I get the answer I was seeking, I also understand why, and I am 100% convinced because it was backed up with an appropriate test. A test! Performed to better answer a question on an internet forum, where everything is supposed to be opinionated conjecture. Awesome.

You are AOK, Jim Day.

[Alan B]

Nice work!!

[spinningmagnets]

That is an awesome post about welding. I have never heard that before, plus kudos for positing pics of every step...

"...The disc brakes had plenty of grab but the issue was traction. It's under sixty pounds so it wants to skid when you brake hard..." Traction is also important. I hear serious bicycle guys laughing about fat tires, but if they have the right tread pattern, more road-contact patch from a slightly fatter tire can help.

[Alan B]

The 27.5 plus size is catching on big time, and might be the right intermediate size between skinny at fat tires at around 3", plus there's a new wide axle (Boosted 148mm) that makes stronger wheels and would help out the hubmotors.

[Bubblehide]

The 27.5 plus size is catching on big time, and might be the right intermediate size between skinny at fat tires at around 3", plus there's a new wide axle (Boosted 148mm) that makes stronger wheels and would help out the hubmotors.

They also make a 29" 3" wide tire. I figured I would upgrade when needed.

[Alan B]

Personally I find the 27.5 is a much better fit for me (and probably most people), and in particular better for ebike battery space, gearing and thrust. But to each his own. :)

[Jim Day]

So I had some issues with the tension pulley system and did some redesign. Here's the current version with the chain guard in place.

[Bubblehide]

Personally I find the 27.5 is a much better fit for me (and probably most people), and in particular better for ebike battery space, gearing and thrust. But to each his own. :)

Yeah, everybody is different, or one size does not fit all. However, I do not for the life of me see how a 27.5 tire sized bike can provide better battery space. A frame only allows so much room, given it's size, small, medium large... or however else the manufacturer sizes them. The gearing is simply what a person goes with, as there are options, options, and options, with gears switchable between a 27.5 and a 29er. As for thrust, the 29er has a higher angle of attack, providing slightly more benefit than the 27.7, which in turn means the motor works less to travel the same distance. But your right, each to his.her own; as long as we are happy with what we have, well, we're happy.

[Alan B]

As I understand it, the triangle has to be shrunk on the 29" tire versions of the same person-size bike. The larger tires take more space, some of that comes from the triangle. Of course if a manufacturer wants to they can make the triangle even smaller, but not larger than the space available. Also, the same gearing and torque from the motor produces more speed and less thrust from 29" wheels. If you want thrust, small wheels win. At some point you are at the limits of gearing, it just isn't practical to go farther. Beyond that the wheels determine what you end up with. I think the 29" is a fad that is starting to abate, and 27.5, for most people, is a better fit. Unless you are over 6 feet tall, in which case 29" may be fine. At a bit under six feet tall I find the 27.5 to be more comfortable and better triangle space. The triangles on the 26" frames can be even larger. But to each his own.

[Bubblehide]

So I had some issues with the tension pulley system and did some redesign. Here's the current version with the chain guard in place.

Hey is that self pedaling, lol. I see the new chain tension-er. It looks like it really cleaned up that chain line, keeping things perfectly aligned.

[mcmccu]

Thanks for posting. Very nice. Is your cyclone the Luna full kit? What was your controller and battery choice?

[Bubblehide]

Yes the Cyclone is the Luna full kit, with their stock kit controller. The battery is a 72V, 17.5AH GA battery. If you want to know everything I bought, you can check out post #14 on this thread: http://electricbike.com/forum/forum/...one-3000-build