Scratch Built - Stealth Fighter Style Bike

Storapa

100 W
Joined
Sep 21, 2014
Messages
126
Location
UK, Warwickshire
Hi Folks, I thought I should post up my project as so many others have taken the time to post up theirs.

About the bike. It’s a commuter for me to ride daily. I live 10.5 miles from work but need to be at my desk at 7.00am and reasonably smart. The spec of the bike is as follows.

Motor - Crystaline HS3540.

Controller –12 FET IRFB4110 Infineon (40A current limit)

CA V3

20Ahr 20s EIG pack (two 10s packs run in series)

A standard bottom bracket width of 68mm

I wanted something similar to a Stealth Fighter but with geometry that I like. Head tube – 69 deg, seat tube 73.5 deg.

Whilst I was designing the bike I fitted the motor, controller, battery pack etc to a surrogate frame so that I could iron out any powertrain issues early on. This was time well spent. There were a few issues that needed a fair bit of attention that I didn't expect. I’m a mechanical engineer, so I've had (and still have) a lot to learn about electrical engineering. The surrogate bike was a bit lively and not that pleasant to ride as it was fully rigid, but it went well.

The wheels I'm using are 24” jump bike rims with a Shimano front hub. Graham (Tiller Cycles) cut the spokes for me. I re-spoked the rear wheel as I wasn't happy with the spoke to rim angle. I re-drilled the hub and used a paired spoke pattern. The front wheel also needed re-spoking as I decided to use a 15mm through hub with the new front forks.

The frame build is still in progress. I've been building the new frame for nearly 2 months now. The rear swing arm needs a fair bit of work at the moment. I’ll put some info about the frame build if people are interested. It’s laser cut sections that I have TIG and MIG welded.

Now some thanks.

Graham at Tiller Cycles (UK) for cutting spokes (several times) and listening to me waffle.

Paul and team at EM3EV for helping me out with my controller and various other bits and bobs. Paul and Moon are always very helpful and efficient.

Justin and his team at Grin Technology for putting some great products out there and his approach to this field as a whole. I wish more businesses could be run like Grin.

Central Laser Services (UK) for laser cutting my parts.

You lot - Endless Sphere folk, for posting so much inspirational and useful information.

Right, that’s it for now.
 

Attachments

  • E-Bike 1.jpg
    E-Bike 1.jpg
    107.4 KB · Views: 4,650
Nicely done, love the mudguards and the Crazy Bobs.

I'm curious, how do you get away with riding something that looks like a lightweight electric motorcycle on the streets regularly in the UK? Even deputy Strate here in Hazzard County would laugh at a 200 watt sticker on that elegantly brutal looking piece of machinery.
 
Hi,

Thanks for the compliment.

Hmm, not sure how I will get away with it to be honest. I will have a road legal mode dialed in to the CA and I will make sure that I always pedal and don't travel at silly speeds on the road, say above 20mph. I'm probably going to paint the bike black, to tone it down a bit. I was also thinking about putting a rack and panniers onto it. I got into this project without considering that side of things, which was probably a bit silly.

I know that there are a couple of Stealth Bombers being ridden on UK roads and several other brutal looking e-bikes. Fingers crossed I suppose.

The other option is to use a Q100H instead of the HS3540 motor.
 
Nice design, looking forward to updates :).

Just a heads up, I've used the exact same mudguards (blue something)... the rear mudguard at 30+ starts bouncing and catching on the tyre. The second time I noticed it was the last as the tyre gripped the guard and spat it off after bending the wires to touch the spoke and the plastic shattered. You'll need to make a support for the bit near the rear shock :wink:.

Whats wrong with the swingarm? It looks good, especially how the shock mounts to the chassis.

Are you intending to charge her at work? Only ask because I've found using the 80% DOD rate then 0-10C (temp not discharge) standard UK weather diminishing another 10-20% can limit your overall desired range/speed. Doing 27 when you really want 30 for some reason becomes intolerable :D.

You've planned well, bike looks sweet :wink: , but just in case use this range calc making good use of your motors efficiency. In the customized parameters make sure everything is as it should be and add a '12 km/h' front wind. It gives a suprisingly realistic value of how much Ah you will use. Work out your 80% DOD = 16Ah @ 23 degC around 13Ah at 0 degC. Once you know how much Wh/km you can afford to burn you can retransfer it back into ebikes.ca calc to see what you need to limit your speed to. Some of our more heat acclimatised friends forget that 15degC+ is reserved for only a few months of the year :lol:.

HS3540 would be fine. Riding sensibly is one way to aviod attention, don't skip red lights or hop on the pavement and as you say always pedal. 30+ mph isn't that noticable in rush hour. See someone suspicious slow down, they'll pass soon enough. 10 miles isn't far, try avoiding major routes. Being black helps, but appear as much like a cyclist as possible, Hi-Vis rucksack, reflectors etc... I regularly filter past slow moving traffic and even politely asking police if I can 'cycle' past road obstructions, car crashes, lorries, haybales etc... when the main traffic is at a complete standstill.

Politeness and not taking the mik, following the regulations for a bicycle (lights etc). As ebikes catch on and become more public maybe they'll clamp down more in the UK, it only takes a few to ruin it for the rest, but you don't sound like a 30+ on the back wheel type, at least not on public property :twisted:.
 
Hi Csmdr, SlowCo,

Thanks for the compliments. I need them at the moment as it's hard going. I knew nothing about e-bikes just over a year ago. This has been a bit of an adventure.

Ccmdr, Funnily enough I had the same issue with these mudguards. As you've also had the same issue, I'll put in a third stay. They do flap about a bit.

The swing arm on the bike is just a mock up to check clearances. I'll have the parts laser cut when I've tweeked the drawings.

I did some testing just before Christmas wrt range. Riding reasonably quickly I can get 50 miles or so out of the pack with some reserve (3.6v per cell). I'll have a look at the range calculator though. As you say, 15 deg + is not something that we get for an extended part of the year.

I'm with you on cycling sensibly and being polite. The other issue that I have found is that cars don't expect a guy on a bicycle in a jeans and a flapping lumi jacket to be doing much over 20mph in town and sometimes pull out after a brief glance. Don't take the p and I think you should be ok. My ride to work is along country roads. I see almost no cars. I only open it up on a section that is deserted and off road. I want to keep it as a bicycle for the time being. I might end up building or rather converting a small motorbike if I enjoy the bicycle.
 
Have a cheeky look on RADONLINE for some cheap(ish) ebrakes. Helps with people not noticing your speed :D. Having variable regen is handy for wet weather too, I've set up 20% regen on any brake application then if I want/need anymore I use variable.

50 miles is pretty good, 85.8V 20Ah pack gives me 35mph for 28 miles on a 'warm' UK day and 35mph for 22 miles on a chilly one (80% DOD). Land this side of the country is dead flat, but suffers from plenty of Wh draining wind... The randy bear county is scary with it's hills :wink:.

What are you making the frame out of, Alu frame/Steel swingarm of just steel dropout inserts?

I'm with you for the moto front, once you experience Electric torque even my 690 seems a little weak :D. When you start factoring in fuel costs vs one hit battery and tiny electric bills with massive e-grin it's hard to think of an ICE as fully satisfying experience.
 
Morning CCMDR,

I like the e-brakes. I wish I had seen those before I went to the trouble of converting some Shimano levers. I like the idea of setting a small amount of regen on initial brake application. I hope to be able to use variable regen as Justin has just introduced it as a software update to the CA V3. I hope that I can get it to work with the Infineon controller.

I was surprised at getting 50 miles out of my pack. The EIG cells are superb. You obviously know how brutal the hills are in Warwickshire.

The frame is mild steel at the moment. I designed it to be made up of 4 discrete components, main frame, seat mount, BB assembly and swing arm. The idea is that I can replace 1 part at a time with a slightly different design / material. Attached are some pics of the main frame part in build.

I like the fact that EVs are so quiet. I rode a VTR1000 until recently. Nice enough and it made a nice sound, but ICEs get a little irritating once you've experienced an EV.
 

Attachments

  • Frame Panels.jpg
    Frame Panels.jpg
    96.6 KB · Views: 2,588
  • Frame in Jig.jpg
    Frame in Jig.jpg
    100.2 KB · Views: 2,588
  • Tacked Frame.jpg
    Tacked Frame.jpg
    91.8 KB · Views: 2,588
Looking forward to the completed pic's.

How do you gain access to the battery compartment? Did you setup the swingarm/wheelbase for 24inch wheels or is it just the perception the fat Crazy Bobs give :) ?

I've stayed around Warwick after buying a CCM 644 DS and a year later the 690... Birmingham way is always a good area to get good cheap fix-er-upers :lol:. It's basically a sumo playground.
 
That's a really nice looking bike, you must have spent a lot of time on the design. I will enjoy following your build progress.

You said you are making the head tube at 69 deg and the seat tube at 73.5 deg. I was wondering why you choose those specs, is it for ergonomics or handling. I am working on a design myself and just wondering what drives the decision for those critical parameters.
 
Morning Gents,

Ccmdr, you gain access to the battery compartment by pulling out the BB assembly. There are 10 M6 fasteners around frame box. You can see them in the frame on jig pic above. I wanted the frame to be as compact as possible. With side covers I would need to increase the width slightly due to the fasteners. It's only 100mm wide at the moment. I'll get a better picture of the BB assembly. There is an access cover at the top / front of the frame where you will access the balance leads. The CA will also live there. I'll get a better pic of that as well.

The design is based around the 24" wheels. I wanted the bike to be as compact as possible as it might end up going on the back of my camper.

I like big singles. I had an XT550 for a bit. It was a cracking machine. I like to try one on really good road tyres.

IdleMind, thanks for the compliment. I spent about 8 months designing the bike. Getting it all to fit has been a struggle. The pack is reasonably large. I also wanted to use a standard 68mm BB.

With respect to the frame parameters, I like fairly upright geometry probably from my road bicycle days. The bike should handle well, and for me at least be comfortable. The bike is for commuting with the odd bit of trail riding, so is a reasonable compromise. You can stress about geometry all day long, as I did. A few degrees doesn't make a massive difference. You will soon get use to whatever you ride.

Nice recumbent btw. I rode a similar machine recently by Cannondale I think. It was surprising comfortable.
 
Is your EIG pack the one you started out with here:
https://endless-sphere.com/forums/viewtopic.php?f=14&t=66020
?
and if so, could you post some details about that pack in one of these two threads? :)

I'm always curious to see details of other EIG packs, to see what others do with them, and how they perform, how they are charged, discharged, monitored, and how the packs are physically constructed.

Sometiems gives me ideas on how I might improve mine. :)
 
Hi Amberwolf,

Yup, they are the same cells reconfigured into two 10s packs. I'll post an update once I get some photos in the next few days.

The EIG cells are excellent. They stay very well balanced, usually within 6mV across 10 cells. I'm not using a BMS for the time being as I bulk charge most of the time with a balance charge if required, but so far I haven't needed to.
 
Right Folks,

Sorry about the lack of updates. I had a bit of a problem with some of the parts that I had made recently.

I had the dropouts and pivot for the rear end water-jet cut. The company that did the job made a right mess of the parts. My feeling is that the material was not clamped and moved about on the machine. The parts were scrap and expensive. Next attempt to get the parts made was using laser-cutting. I decided to try a company that a friend uses locally and recomended. They had the drawings for 5 weeks. They kept promising to do the job. I gave up and went with another company. They were polite and helpful. The result was parts on my doorstep some 5 days later. Job done.

The first photo is the delivered parts.

The next photo is the machined parts ready for the jig.

More updates tomorrow.
 

Attachments

  • Lasercut Parts.jpg
    Lasercut Parts.jpg
    144.7 KB · Views: 2,581
  • Machine Parts.jpg
    Machine Parts.jpg
    75.9 KB · Views: 2,581
Wow!. That's spot on. Beautiful!! What are the chances of sending me some drawings, I'd love to strip mine and build this piece of pure art.... 8)
 
Right, a bit more of an update.

I was not happy with the original frame so ended up redesigning it over the last couple of months. I've now put the controller into the frame. I figured that the UK ambient temperature is not that high, but the chances of rain are. The controller has been removed from it's case and the frame is now the heat-sink.

Firstly a new seat pod.
 

Attachments

  • Seat Pod 1.jpg
    Seat Pod 1.jpg
    121.7 KB · Views: 2,580
  • Seat Pod 2.jpg
    Seat Pod 2.jpg
    161.6 KB · Views: 2,580
mxer said:
Wow!. That's spot on. Beautiful!! What are the chances of sending me some drawings, I'd love to strip mine and build this piece of pure art.... 8)

Hi, thanks for the compliment.

The drawings are not complete at the moment. I've found a few issues along the way as you do. I'm not sure about releasing them as I'm over 800 hours into this project. Let me have a think about it.
 
Completely understandable, and I apologies for asking, think I got as excited as you are on the build :lol: .

Like I said, pure art!!..congrats.

Will certainly be keeping an eye on this one, thanks for posting :wink:
 
One more update for today.

The seat pod is finished. The main frame is tacked and in some places finish welded, as is the bottom bracket assembly. I couldn't resist trying the forks in the frame.

You can see where the controller electronics live. They sit inside the main frame, just under the seat pod mounting. The frame has internal reinforcements that stiffen the lower portion.

 
Thursday's update on the build.

I finish welded the main frame. I then set about building the swing arm. I forgot to take a picture of it in the jig, but if anybody in interested I can go back and photograph it in position.

New Frame.jpg

Bike - New Frame 4.jpg

I then spent some time finish welding the swing arm and damper mount.

Bike - New Frame 3.jpg

Bike - New Frame 1.jpg
The final picture is of the BB area. This is 3mm thick material. The BB assembly is removed so that you can slide the battery modules into the frame. I wanted to try something slightly different. I'm not sure that I like it that much, so might end up building a regular sheet metal version.

BB Detail.jpg

There are a number of small machining jobs to do now. Hopefully I'll complete most of them over the weekend.

Any questions etc, let me know.
 
A small update.

There a lots of little bits to machine now, like the damper pivot bushes and spacers, brake hose guides for the frame and motor wire outlet etc.

The idea for the motor wire outlet came from this site. I can't find the original post. It makes a better job of looking after the wire than the original plastic guide.

Motor Cable Guide.jpg


The rear brake hose guides were also an idea from the site. I'll braze them to the frame and swing arm tomorrow.

Frame Cable Guides 2.jpg
 
After a weekend of many little jobs on the bike I got to ride it, sort of. I wanted to see what the bike felt like, without the aid of the motor.

This was the first time I rode it. It felt great. The geometry was spot on (for me at least). This bike is for commuting and a bit of trail riding in the future. I took the geometry from a bike I ride and feel comfortable on, 69 deg head tube, 73 deg seat tube. The wheelbase is 1175mm.

First Ride.jpg

Still lots to do, but it's getting there. I need to tidy up the wiring and finish the bike loom so that I can try it under power before I strip it for paint.
 
Back
Top