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Redmohawk
05-06-2010, 04:50 PM
OK Fellow nutters, I found the photo of this jigger and just fell in love with it right off the bat! I want to make something very similar for the road, but with a big twist (Electric powered, Currently putting a 20kw continuous Hub motor together to power it) Don't laugh to hard the power/torque should be better than a xr600 motor. Only prob is distance traveled before a flat battery is going to be low without big buck batterys.

My question is, whats the most suitable material for the frame ? I'm guessing something like chrome molly is the way to go ? I want something light and strong but I've been told its a bitch to weld due to having to pre heat welds etc, I'd love some advice I remember a guy that used to make kneeler's from scratch around here years ago tell me to use rynolds 355 tube ??? as you could weld it with a mig without pre heating and the tube didnt become brittle. Am I on the right track there???

If it can be bent with a hydraulic tube bender would be nice to !

http://www.asfphotos.com/upload/1275777308.jpg

wackyrider
05-06-2010, 05:15 PM
I'm looking for something similar myself, so let me know what u find. The issue is getting a material strong enough, but not too heavy and doesn't cost an arm and a leg. Plus not to be impossible to weld. Just got myself a 12T hydraulic pipe bender and we just got a new welder here as well.

Redmohawk
05-06-2010, 06:14 PM
Cost is an issue but with the amount of material used even $20 to $30 a foot I would pay as long as i dont need to by it in 8 m lengths lol I was told ages ago the stuff they make Group A roll cages out of is the shit to use and it only comes from pommy land but that info is 15 years old an banged around in my head all that time lol

fimpBIKES
05-06-2010, 06:58 PM
more info on the motor mate!

are you in sydney? the place to get tubing is called "british international trading"
http://www.britint.com.au/

Redmohawk
05-06-2010, 08:09 PM
Thanks fimp , Looks like its going to be made from seamless mild steel! As reynolds 531 and 15CDV6 are the good stuff thats easy to weld
But without heat treating them you cant bend them, and then you loose 2/3 the tensile strength on average once bent. Prob to much stuffing around for a one off project like this, for me anyhow. And I just love the curves of the frame, I could probably do something similar with no bends hmmmmm time to get the crayon's out lol

What you want to know about the motor mate? Not sure of your background/knowlage on electric motors so here goes with basic info. Its a 3 phase rare earth magnet brushless motor using the stators from a fisher and paykel washing machine (3 of) machined to fit together to make one unit then rewound with heavyer wire. The stator is fixed onto the axle and an aluminium housing retaining the rare earth magnets revolves around the stator mounted on bearings running on the axle. The wheel/tyre will be directly mounted to the magnet housing. Torque from the motor is maximum at zero rpm so the motor controller will be torque based not rpm so you can pick when you want to do a burnout lol. Voltage can be anything from 12 volt to 144v depending on controller and how its wired etc. I will be aiming for 48 volts and using sealed lead acid batterys for the initial setup with lithium to follow (when i win tats lol) Motor and bike frame is the easy part really, Try and buy a brushless motor controller that will handle 48 volts at min 400 amps continous that will fit into a bike frame easy lol

When i get it a little further along I'll post up some photos for you.

05-06-2010, 08:22 PM
I made a similar version of this for my Highschool science project many years ago.Turned out qutie strong but voltage supply wasn't up to demand,although it was impressive while it lasted.

RevHead
05-06-2010, 08:30 PM
hey ive always said why cant they charge while thy drive, its got me fucked ,use 24 volt generators x2, 1 on the back wheel 1x on the front wheel then feed that back to a big lithium battery ,surely it can be made to work

megareg
05-06-2010, 08:57 PM
Impressive output from washing maching motors, I like it, and I'd like to know more, any chance????

Redmohawk
06-06-2010, 12:38 AM
These are not your usual washing machine motors lol here's a photo of the rotor with the perminant magnets in it (wont be using it, its plastic and has shit as magnets in it, I'll be using rare earth magnets strong enough to break your finger sort of stuff)

The only part of the motor I'm using is the bit mounted on the tub in the second photo, and I'll be using 3 of the armatures , but only the laminations the windings will be cut off first so 3 sets of laminations can be bolted together. Then much larger wire will be used to wind the new coils.

To achive power levels I desire currents in the order of 400 amps at 50 volts will be needed. These sorts of power levels can turn wire from batterys etc to molten projectiles traveling at hundreds of kh/h. And may spike higher upwards of 1000 amps.

A friend of mine from many years ago when I first started playing with this kind of shit had a little "accident" and now he is missing the end of his index finger to the knuckel! poof and it was gone lol

http://www.asfphotos.com/upload/1275786432.jpg


http://www.asfphotos.com/upload/1275801041.jpg

Redmohawk
06-06-2010, 12:51 AM
Rev , the plan is to use 4 sealed lead acid batterys mounted real low under the frame like where the gearbox of the bike in the top photo. There cheap and can supply the instantanious current I need for 20 kw but at the currents needed would be depleated in very short order (about 10 min to a smoking mess lol) But 10 min would be real fun ! A 20kw electric motor depending on setup can have the low rpm torque of a 750 cc IC engine. There will be plenty of room for a very small electric generator I have made one in the past that would fit easy and produces enough to run at highway speeds just. Ideally I would use a off the shelf free shaft gas turbine (yeah jet engine! but it has an output shaft) driving a generator the whole unit would fit under the tank easy and produce about 10kw continus but would cost abut $7k .

Swordsy
06-06-2010, 01:25 AM
The other thing to look at is a switchable motor, Ie switches from series connected to parallel connected. This will give you max torque at no rpm (series) and then max torque at approx 3000rpm when you switch (parallel for a 3 pole motor, 1500rpm for a 6 pole etc). This will need contactors to switch between the 2 (added weight) but should give you better efficiency. You will need all the contacts for the motor to come out to a contact block for this to be wired properly. 20kW contactors are fairly small. The heaviest part will still be your batteries.

Redmohawk
06-06-2010, 10:11 AM
Swordsy , I assume your talking about a diferent type of DC motor (one the has a field coil and a stator coil) like what most co nventional high powered DC motors IE forklift motors etc Yes your right there changing the motor setup inn that case will change the torque to rpm dynamics.

This motor uses Extreamly powerful rare earth magnets instead of a field coil so the motor torque/rpm curve is resonably fixed but MUCH more powerful on power to weight than the type of motor your thinking of. The windings can be changed from star to delta like a coventional 3 phase 415 volt motor and this will change the motor setup but isn't really nessassary in the setup. There are other options also in the winding stage of the motor , such a a special winding pattern where by not all of the stator posts are used. This produces a motor with basicly a magnetic gear reduction built into it. With this special winding setup the magnetic revolutions inside the motor can be higher than the physical revoloutions of the motor by up to 12 times, effectively giving you a 12 to one gear reduction without any gear friction or mechanical losses. Producing a motor with 12 times the torque of the same sized motor in a conventional winding patteren. The rpm of this winding patteren is limited by the frequency limit of the 3 phase controller. Most controllers can control motors up to and above 50,000 rpm so one 12th of this would be your max rpm say 4000 rpm max. This will be far more than i will need as 1000 rpm equates to 100km/h

probike
06-06-2010, 10:24 AM
chrome moly isn't that bad for price 1 1/4 x 58th [31mm x1.6] $18 per mt from performance metals and they will sell you any length you want welding is very easy here's a link to lincoln with tips on c/molly welding http://www.lincolnelectric.com.au/knowledge/articles/content/chrome-moly.asp

also you could use http://www.performancemetalsaustralia.com.au/stocklist/mildsteel

Redmohawk
06-06-2010, 04:59 PM
Thanks probike but whats it like to bend?

JackTar
06-06-2010, 05:23 PM
quote:Originally posted by davo

I made a similar version of this for my Highschool science project many years ago.Turned out qutie strong but voltage supply wasn't up to demand,although it was impressive while it lasted.


As if you went to school.

probike
06-06-2010, 06:14 PM
not to bad to bend what sort of a bender do you have

Redmohawk
06-06-2010, 06:15 PM
Just an elcheapo jack type with cast mandrels

Hillsy
06-06-2010, 06:38 PM
Have a look over here:

http://www.thefont.info/contents.htm

It's chopper orientated, but it has lots of info on type of tubing to use, tube benders, etc.

fimpBIKES
06-06-2010, 07:27 PM
there was a bloke in newcastle doing mandrel bending for $15 a bend

i would farm it out and get the bends done properly
just mark out the result you wont at the end on mdf, put some nails in it so the tube will only fit once its right and take it when you pic up the bent tube

saves to be sure before you get it back to the workshop

Redmohawk
06-06-2010, 09:38 PM
Thanks Hillsy was an interesting read the pipe bender is a great idea , but I think I'll go a little flash and build something with a little more potential for all kinds of bend radi . With some considerable discussion with a few locals that have been building slider and bike frames for 20 odd years I've decided to go with rated seemless tube like the 350psi cold drawn stuff from performance steel. The general consensus is the weight penalty for the type of frame is resonably low, with the advantage of being very easy to bend and weld with any form or welder without cracking issues. Now thats sorted on with the show lol

Redmohawk
06-06-2010, 09:39 PM
When I have the tube roller up and running I'll post some photos , the idea has been stolen from a local.

Booster
06-06-2010, 10:45 PM
Head up to Numurkah Honda and talk to the Peter , he has made a few frames and could offer a few tips, keen to help a diy ,and would get a kick out of your powerplant , bends his with sand and oxy .

Redmohawk
07-06-2010, 10:32 AM
Yeah might do that booster, thinking of seting the bike frame up almost identical the the photo up the top. Thinking Build it with an XR600 motor I want BIG single but a eletric sart would be nice (I know where a DR650 motor is) is a possability i guess. Get it reg , then build the new frame etc (yeah avoid the rego issues of the new frame etc etc lol) Then once its all up and running make the battery/electronics cradle mount to the engine mount positions so in 20 min you can swap out the IC motor and rear wheel and drop in the battery pack and electric rear wheel.

Redmohawk
07-06-2010, 10:45 AM
Hmmmm scratch the big single, maybe the next project lol. Found a few local donor bikes 200's etc almost ready to reg might be a better option to get the ball rolling and prob more in the spirit of the idea.

Any of you genius's have an idea how they might have set up the head stem bearings in this jigger? As from what i can make out it must have some kind of ball arangment in the head mounts to allow for the suspension travel , but an idea how to mount bearings in there as well?

pappas
07-06-2010, 12:30 PM
Looks like the forks have a rod attached that run up the inside of the head stem, with bearings top and bottom. The silver piece at the bottom of the stem sleeves around the outside of the stem and pushes the lever arm of the piece attached to the shock. It looks to only have about 20-30mm of travel though. That's my edumacated guess anyway.

Redmohawk
07-06-2010, 01:47 PM
Yeah thinking for the first one (yep might be 2 lol) I'll just use some very short upside down conventional forks but make the frame look very similar see how that goes, less muching around to get geometry all correct. Let alone mucking around with spring rates etc with the setup up top. So looking for a set of real short upside down forks with good sized disks maybe a set off some sort or 125 or 250 road bike ? if it had some nice sexy wheels front and back even better! lol

Booster
07-06-2010, 06:31 PM
Front bearings look to be sealed swivel ball type, like a rose joint end , use in ag stuff often,have one or 2 in the shed , Stan probably has them on the shelf,
require a parallel bore and circlip

Redmohawk
07-06-2010, 06:43 PM
Thanks booster , Mk2 will prob have a go at the front end like that. Going to start with some real short upside down forks maybe off a pit bike or something? Just had a big blow to the electric motor plan turns out the washing maching base is a no go as the number of posts on the armiture must be a multipul of 12 to set it up the way I want. The washing machine motor has the wrong pole count. So now I have to get laminations laser cut to my spec's and it will truely be a one off motor! Advantage is I can make the motor diameter bigger to suit the rim I use also increasing torque further.

DiscoDan
07-06-2010, 10:45 PM
quote:Originally posted by Redmohawk

Yeah thinking for the first one (yep might be 2 lol) I'll just use some very short upside down conventional forks but make the frame look very similar see how that goes, less muching around to get geometry all correct. Let alone mucking around with spring rates etc with the setup up top. So looking for a set of real short upside down forks with good sized disks maybe a set off some sort or 125 or 250 road bike ? if it had some nice sexy wheels front and back even better! lol

I've got the front end off a TZR250 (the later v twin ones like this http://www.motorcyclelane.com/img/Shopping/3XV-1.jpg) that might suit. It's got a drop-shoulder top yoke so the forks are even shorter than normal for a 250 smoker. The legs will need re-chroming though as they're pitted up and one of the brackets for the mudguard is snapped off the fork lower. Let me know if you're interested

Redmohawk
07-06-2010, 10:55 PM
Thanks disco but there still far to long, got to be much shorter Like 6 to 8 inches . Think i've found some off a new pit bike thats being wreaked due to dead motor. Anodised upsidedowners only thing is a single side disk mount but will prob make new ones anyhow if doable.

Tony OW31
08-06-2010, 08:39 AM
quote:Originally posted by Redmohawk

Thanks fimp , Looks like its going to be made from seamless mild steel! As reynolds 531 and 15CDV6 are the good stuff thats easy to weld
But without heat treating them you cant bend them, and then you loose 2/3 the tensile strength on average once bent. Prob to much stuffing around for a one off project like this, for me anyhow. And I just love the curves of the frame, I could probably do something similar with no bends hmmmmm time to get the crayon's out lol



I've made at least 10 frames out of Reynolds 531, never had to heat treat it to bend it. To get a good bend you need some cerabend (cerametal is available in different melting temperatures).
The best method of joining for motorcycle frame use is bronze welding.

Redmohawk
08-06-2010, 12:27 PM
Ok tony you have my interest Whats cerabend for a start ? I'm assuming its a metal and how do you use it to bend reynolds 531?
The guys around here state the "best way, ie strongest is tig with same material as filler" and bronzing as second but prob easyer only thing is its been 22 years since i used a oxy set and did any bronze welding lol and i dont have an oxy I have a ark, mig and planing on buying a dc tig next week. The supplyers of reynolds 531 stated the strength reduction from bending figures so took that as gospal.

Have sort of decided on the mild steel/mig route for the first frame project as its my first from scratch and would like to have something i'm familar with to start from. But I'm sure i could gain access to an oxy set without to much trouble and if you have some insite into bending 531 i would be very interested if you could point me in the direction of more info. From my searches on the net i havent found much positive info so far.

Tony OW31
08-06-2010, 12:51 PM
quote:Originally posted by Redmohawk

Ok tony you have my interest Whats cerabend for a start ? I'm assuming its a metal and how do you use it to bend reynolds 531?
The guys around here state the "best way, ie strongest is tig with same material as filler" and bronzing as second but prob easyer only thing is its been 22 years since i used a oxy set and did any bronze welding lol and i dont have an oxy I have a ark, mig and planing on buying a dc tig next week. The supplyers of reynolds 531 stated the strength reduction from bending figures so took that as gospal.

Have sort of decided on the mild steel/mig route for the first frame project as its my first from scratch and would like to have something i'm familar with to start from. But I'm sure i could gain access to an oxy set without to much trouble and if you have some insite into bending 531 i would be very interested if you could point me in the direction of more info. From my searches on the net i havent found much positive info so far.

Cerabend is basically cerametal, a very low melting point alloy. You cap the tube you want to bend and fill it with the cerabend, cap the top and then bend the tube. it works in a similar fashion to filling with sand, but is far superior.
The reason bronze welding is superior is not from a strength perspective, tig welding will give a weld with a greater UTS, but from the pov of the stresses involved in bike frames the bronze welding is more forgiving when it comes to stress fractures.
Frames I made that only did short circuit racing where fine, but those that went to the IOM and other road circuits held up far better when bronze welded compared to tig welding.

Chris41
08-06-2010, 12:58 PM
If you still want to use chrome moly you could build a frame similar to a Harris or Rob North and use as many straight pieces where possible.
When I've spoken to sidecar builders there is always a toss up between tig or bronzing tig is stronger though.

Redmohawk
08-06-2010, 03:34 PM
Tony your a dead set fucking legend ! Just chased up a mob in melb that sell something just the same (just a different brand name) top shit mate! makes bending tube so easy in just about any kind of bender ! Works out to be about $70 a kg so $200 dollars worth of this shit should be enough to keep me happy bending tube for some time. Looks like i might be shopping for an oxy set to lol.

Redmohawk
13-06-2010, 07:12 PM
Ok guys and girls if you want to use this stuff (not cerrobend but the same shit different name even made in aus!) give August metal and alloy company a call and ask for LW4 is the stuff you want (melts at 70 deg C) is about $70 a kilo there in melb and the number is 0397374816.

livewire
16-06-2010, 01:28 AM
just noticed in latest 'Silicon Chip' that they advertise a book "Build your own electric motorcycle"
Written by Karl Vogel. $47.95

Skorpion
16-06-2010, 03:31 AM
hey, the new hybrid toyota camry runs a charging system so that when your brakes are engaged the electrical circuit is reversed and the elec motor runs as a generator. just another idea to throw around.

Redmohawk
16-06-2010, 09:26 AM
Livewire yeah I thought hard about writting a book about it to lol, I have a book 1/4 done on generating your own power from wind hydro solar. There is more people wanting to read about that sort of stuff than can afford to do it, Is a nice little cash earner if you have a good rep as a writer (I don't as i cant spell for shit lol)

Skorpion yeah the hybrid toyotas are an easy way to access cheap battery packs high power electronics and inside the gear box there are 2 10 kw electric motors one is used as a generator and the other is a drive motor/regen unit basicaly the same windings are slightly different I would guess. If you can pick up a cheap crashed car the bits would prob be cheap at a wreacker as no one is interested in that stuff atm (to hard for most to play with) And if anyone decideds to do so please be careful 144 DC volts from a battery pack like these can kill and burn you much worse than 240volts from the mains!!!!!

I'd love a few totota puris electric motors battery packs and controllers, I'd hybrid Burtha! Just to expensive any other way (she does weigh 4 ton lol