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Mini moto mayhem

Level 7

Time to start a new project, This one is something I had in mind when I finished my first build but because of time/money it didn't start. This is going to be a long termer but hopefully it should be finished by the end of the year as there is a lot of work to do and hopefully it should help spread the cost of the hardware.

The name should give away the concept of the build, basically I have a couple of old minimotos that I can't run on track anymore (noise restrictions) and so I thought it'd be a cracking idea to utilise one for a build.

Ok some pics of where it's at

The bikes have been stored under a table in one of my sheds, it will give you an idea of how small these little motorbikes are.

A bit of a zoom shot, you can make out some old bodywork there too, this body work might still be used but I figure that i'll have to make some new bodywork or at least add acrylic windows and modify these ones.

Here it is next to my road bike.

So now the bike has been rescued from a life in a garden shed, this is what it looks like in isolation. The reason I have chosen this one is that it has a very nice trellis frame with plenty of points to mount the hardware.

Ok so now it's time to remove the engine, don't worry it won't go to waste, I have another frame that it can go into.

The bike without the engine, there's plenty of space for what I have in mind. I will keep the throttle and brakes, It will need brakes to help it stop....err yes you did read that right, I plan to put an electric motor in the bike so that it will still run and i'll still be able to ride it. (it'll raise a few eyebrows at Lan parties)

A view from the front, the PSU to run the PC and battery for the electric motor will fit under the seat. It'd be good to figure out a way of running the PC and the electric motor off the battery but failing that it will run off two different circuits.

I have made out a board that is the same size as a mini ITX board to give me an idea of how the mobo will be mounted

The system will be water cooled, I test fitted a rad, which is just a little too big so I will have to use smaller items. The reservoir will be in the obvious place, the petrol tank (gasoline for our American friends :eyebrow: ) There will be two rads mounted inside the frame on both sides of the bike.

So hang on tight and watch where this project goes, you should be able to guess what direction I'm going in with the coolant

Level 7
I got home from work and the other half was annoyed with me, a parcel had been delivered from AquaTuning (Germany) and she thought I'd been spending more money (y'know how it is) I was baffled as I hadn't ordered anything and thought the parcel had been sent to the wrong address.

It had my name on it and thought what the hay and opened it. Inside was a modding kit from Phobya. 3 nice fans, some braided sata cables, LEDs and a fan controller ... oh and some gummy bears which got damaged in a series of small accidents involving me and my stomach.

Then I remember .... It was a prize for D33P THOUGHT and the write up it had in CUSTOM PC magazine. So a big thank you to AquaTuning for sending the Phobya kit through and also to Corsair for the Case and PSU. Also a Huge thanks to Combatus for chasing it all up :thumb:

So the fans came in handy as I have been looking through the Net trying to decide what to get, (they still might change yet) but for now they're a god send as I can see that they fit perfectly.

The fans look pretty good and should give off a nice red glow through the frame.

Right now for thing that's been bugging the hell out me, the reservoir. I really don't like the first idea as the reservoir will break up the lines and shape of the tank. The bike has been screaming at me every time I walk past it. I plan to use Mayhems fluid in this build and want to do the Aurora fluid some justice. So I have ordered up a solid block of acrylic and will make a custom reservoir, the shape will be the Mayhems water droplet logo (If Mayhems doesn't mind) and the return flow will go through the top of the tank, much like a fuel breather hose.

here's a mock up of what I have in mind, I need to see a man about a dog for this but it should be possible. I will use an anti kink coil as the hose will be exposed, it will help to keep the hose open and also protect it.

Another small job that I've done is to fit the front fender, which wasn't as straight forward as it should have been as I had to remove the whole front end and turn it around as the mounting brackets were facing the wrong way.

and finally the where it's at pic

Jobs to tackle next, fit two 12 Volt batts, fit the electric motor and fit the PSU.

I redesigned the res for the tank and realised that I'd need some help to achieve what I had in mind, I contacted Phame (of Golden Pi fame) and he kindly agreed to lend a hand, This is the sketch that I gave Phame, yeah I know not a lot to go on but he's been given free reign and so I'm looking forward to see what he comes up with.

I also asked Phame to follow the contours of the inside of the tank, so I sent him a block of acrylic and sliced off the top of the scrap tank that I'd been using for mock up. He has sent through some pics of the mapping of the inside of the tank. (It all looks like witch craft to me)

and finaly some pics of the computer surface model (again I haven't a scooby about it)

The top of the res will petrude out of the tank in the form of the Mayhems logo and will be back lit with LED's. Phame will keep a small log of the machining, and I'll look forward to posting the result

A BIG THANKS goes out to Phame

Ghosted Viewpoint


A big thanks to Michael and welcome aboard. (I assume you have your own helmet)

So with the formalities done it's time to crack on with the update..

I mentioned that I had re-done the motor mounting plate, this was made out of a thicker gauge steel and now reduces the flex dramatically

With that out the way it's time to focus on getting the seat unit mounted properly. The seat unit I have is from a different bike, no real worries there it means new brackets will need to be made for the it to fit properly, It is quite critical that it is done correctly as there needs to be no flex in the panels otherwise they'll eventually crack and break. I rummaged around in my sheds and found a hand full of fasteners from my sports bike

Do you guys know the name of this type of fastener ? They are 1/4 turn quick release D ring DZUS fasteners (you're a clever bunch and already knew right ?) I'm going to use a lot of these on the body work to give it an authentic race bike feel.
So I need a starting point to take all my measurements from, I will use the single mounting point near the headstock. I basically measured and bent a strip of steal, nothing flash but solid (still needs tidying)

The sprung clip part of the fastener just slides into position

The D ring part of the fastener is then poked through both holes and the spring gives a satisfying click and the assembly is locked into position, these are really nice and I'm amazed that they're not used on some of the car/hotrod based case mods.
So here it is all in position.

So that's the front of the seat unit secured, the back end still needs to be done (next update) but in the mean time when I test fitted the seat pad, something was niggling me.. the bolts just look plain ugly and needed sorting

So after a bit of head scratching and a chat with the girl friend, she suggested that we could make a seat cover, I wanted it in red suede, but It would have to be a permanent fix, and so we settled on red velvet, So I was rather fortunate, the girl friend dragged out the sewing machine and upholstered the seat pad for me. Result :thumb: (The trick is to make them think it was their idea) This is a gorgeous colour and I'm going to have the frame powder coated in the same colour.
Think I'll run the same colour Mayhems coolant too

Ok Crackin on, it's time to address the mother board tray, remember the old PC that was gutted ?

I cut out the the part marked out in black with my Dremel, the edges filed down and the whole thing sanded down. After a coat of primer, I riveted it back together and very happy with the result

I saved the springy bit for the expansion slots ( Does anyone know what they're called ?) this was easily cut into it's new shape with a pair of scissors.

So know it's time to see how it will fit on the bike

I haven't ruled out using a riser ribbon for the graphics card, I need to check out how the belly pan fits as that will protect the mother board from boots/feet when riding the bike.

That's all for now but just to say again, Freakin brilliant that Mayhems is on board, THANK YOU.
(I now have a clear colour scheme and race graphics in mind)

This update is about getting the motor running and getting some drive to the back wheel. I have been down Maplins and got some connectors, I couldn't get the other connections to fit what was already on the motor control unit. So simple solution, change them for something readily available.

I have an old three pin fan extension, so I will rob the connectors to use with the throttle.

I have removed the brake and brake light connections, as there is mechanical brakes fitted and I really don't like the idea of an electronic brake, I really don't think you have the same level of feel as a good old fashioned pads and disc set up.

So, first things first, I fitted the motor control unit onto the top battery tray, a positive on one battery was connected to the negative connection on the other battery. This will give me the 24 Volts that I need for the motor.

This has highlighted a small problem with the battery and wire being visible through the frame and it looks awful. I hadn't removed the brackets from the frame in that area, so I can use those points to mount a small panel.

It's an awkward shape. I placed a piece of card behind the frame and drew around the inside of the frame to get the shape I needed.

With the panel cut out I can use it as a template and transfer it onto a piece of white plexi, a logo will be placed there and so I will be searching for another sponsor, I have someone in mind and hopefully they'll see the potential of having their brand on the bike, rather than their products hidden inside a case.

That's all for now, but the bike is running and i have been out for a ride, I will share the results on the next update. I've been to busy giggling to myself to get a video done but I will sort that out, once I've stopped having fun on the bike

As promised the test ride of the bike, Nothing fancy no music but quite a handy lil exercise as I have noticed a knocking noise that I can't hear while riding. The chain has seen better days so a replacement needed. Enjoy the Vid.

The nice thing about helmets is that you can't see the rider grinning like an idiot


Small update this time, I have fitted the PSU and it fitted nicely into the spot that I wanted it to go, you'll notice the fans and grills have been fitted. I went with the white golf ball type, nice lil fans and they'll look at home when the build is complete.

I have been lucky and the other half has bought me some bike bits, some of these I have been waiting for, for a quite a while...

New forks (the old ones were bent) , new bars and brake levers... nice and sparkly.

Next up is a set of wave brake disks, a new caliper, new triple clamps and some other stuff that will bling up the bike when it comes to final assembly. So of to the spares box with this lil lot, we'll see these again later on in the build.

There was also some new brackets for fitting the bodywork, These are the bits I needed badly, so now I can fit and see where I need to chop down the fairing to allow access and viewing for the motherboard. I have had to make a few minor adjustments so that the bodywork will accept the Dzus fasteners.

I'm happy with the result, even with the mish/mash of panels the transformation is huge. there's still a few brackets to make up but for now one last final where it's at pic :cooldude:

Level 7
It's been a crackin day outside so time to get some more progress done on the bike

I have an old PC in the shed, it's never gonna be worth getting sorted and I'm low on material.

Not impressive is it ? but it has something I want so lets get this thing torn down, like I said it was a nice day, so took advantage of the sun and done it in the garden.

Now for the bit I want, not having any experience with the mini ITX form factor, I'm assuming it can still be mounted on to an ATX mobo tray (backward compatibility) and on further measuring I should be able to cut down the mobo tray and make use of the I/O shield and expansion slot mountings

and after drilling out all the rivets, I have what I want and also some useful material to make "other things"

I quite like the power button too, so I think I'll use that and mount that on the tank somewhere.

we will come back to the mobo tray later but in the mean time I have had some "bits" delivered for the drive system, motor, throttle, batteries, ignition, charging unit and port and motor control unit.

The motor control unit appears to have some excess connections (or at least to me there are) The light connections can go, or they might come in useful for adding bling when running, ohh and the brake connector can get binned too, pffft brakes ....

Fitting the motor was easier than expected, It's just mounted onto two strips of steel and bolted onto the frame, I did have some clearance issues with the front sprocket and the chain rubbing against the frame but I packed out the sprocket, ground down some of the motor cover and filed some flats onto the frame. This has allowed me to pinch a few millimeters and the chain clears the frame quite nicely.

It does however raise another issue about safety, namely getting my toes chewed up by the chain and sprocket, Luckily I have an off cut from an exhaust that I'd fitted to one of my race bikes. So I will run the header up to the graphics card (funky backplate to be designed) and the heat shield for the small piece of off cut will be a dummy exhaust and also double up as a chain guard.

So on with the update, yes it's quite a biggy

Now I have to think about fitting the batteries, I made a template so I could mock up the position and also use to mark out on my new found material.

Slightly over sized, to allow for a bigger battery to be fitted and some insulating material to stop it rattling around.

The position of the first battery on the rear of the frame

This will be hidden under the speed hump on the back of the seat unit

Ohh nearly forgot, I have a new seat unit, the paint finish isn't so good but it's very unlikely that it will stay this colour, as I plan to do a full race livery. Colour undecided it depends if any sponsors come forward.It would be great to have a nice ASUS or Mayhems livery, If not (the most likely scenario) Then it will be a Cal Crutchlow Replica (fave MotoGp rider)

Ok now for transferring to the steel from the old pc

and cutting out

So after bending, the tray fits onto the rear of the frame like so

and with the battery fitted

I run out of cutting disks so the second battery position is where the template is, that'll be done when I get more disks.

I have also been thinking about cable management, any loose cables is going to be bad news. I don't want them getting caught in the chain or wheels. I'm not going to win any MotoGp races if the bike don't run properly.
The idea is to use aluminium blocks with channels slotted into them and an acrylic cover over the top. I can bolt these all over the frame an keep those cables neat and safe.

Ok to finish off here's a couple of pics of the rear end of the bike, the ends of the frame under the battery tray are screaming for a set of exhaust tail pieces.

The tail unit has some beautiful lines, I'm liking how it follows the rear of the frame

That's all for now

Level 7
Here is a the first off design for the res.

I need to touch it up abit, like the outlet and inlet hose fittings.