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10kW Motorbike Conversion

Posted: Mon, 06 Aug 2018, 17:09
by moestrei
Hi Everybody,

I am in the process to convert a 250cc Kawasaki motorbike into a 10kW EV.
I got the bike, a 10kW Golden Motor motor and a 72V (VEC500) controller from the same company (...is not the best, I know, I know).
I also have purchased a Lithium battery bank (Winston) 72V/90Ah....24 cells actually.

The plan is to attach the motor to the rear swing arm (keeping the distance motor and rear wheel axle constant) and use a belt drive (Gates Polychain) system.
So far so good, I also got a list of Certifying Engineers from RMS (I am in Coonabarabran/NSW) but everyone I contacted either did not reply, was not interested or sounded like a rip-offerer. So do members know a good guy who is happy to assist in getting the bike certified at reasonable rates?
I am an Electronics Engineer and have a complete workshop available so the engineering is basically covered....it is just the certifying bit.
Surely there should be someone in Sydney/Newcastle or similar.

Thanks,
Martin

Re: 10kW Motorbike Conversion

Posted: Mon, 06 Aug 2018, 19:46
by jonescg
Hi Martin,
The motor on the swingarm is a well travelled route. If you can make it fit I think it will work quite well. The battery though - a little bulky for the energy stored, but the right price I guess. At least with the motor out of the way you should be able to fit them. Otherwise you could go for a 10 kW hub motor and that would free up a lot more room for batteries in the chassis.
I hope there will be a NSW member who can chime in about RTA certification and approval.

Re: 10kW Motorbike Conversion

Posted: Mon, 06 Aug 2018, 21:56
by antiscab
I was under the impression the certifying engineer just had to be a full member of engineers Australia?

Could you not just sign it off yourself?

Re: 10kW Motorbike Conversion

Posted: Tue, 07 Aug 2018, 10:09
by Richo
Seems he can't...
DEPT Transport IB-102R wrote: An engineering signatory who certifies a motor vehicle with respect to its construction or
modification must:
• personally inspect the vehicle; and
• ensure that any construction or modification of a vehicle complies with the
requirements of the Road Traffic (Vehicles) Regulations 2014 and where applicable,
the appropriate Australian Design Rules; and
• issue a comprehensive engineering report, which satisfactorily addresses any
concerns raised by officers from the VSS.
Signatories recognised by the VSS will generally have demonstrable experience in the
automotive industry and are members of one of the engineering organisations:
• “Engineers Australia” (formerly called the Institution of Engineers Australia), or
• The Society of Automotive Engineers, Australasia (SAE-A) - Automotive Signatory
Group.
This will determine what work that they are eligible to perform.
Membership of “Engineers Australia” is not the only criterion used to ascertain an individual’s
suitability to be an engineering signatory and people who have extensive experience in their
specific areas of work may appear on this list. It should be understood that few signatories, if
any, could offer consultation services for all aspects of automotive design. The client must
be satisfied that a particular signatory is qualified and experienced in the specific area
required before commissioning them.
Professional engineers who are members of “Engineers Australia” are bound by a code of
ethics limiting them to only give advice in areas where they are qualified to do so.
Officers from the VSS may use their discretion on whether to accept an applicant or to debar
an existing engineering signatory, based on a lack of pertinent experience or an
unfavourable record.
Signatories recognised by other state or territory registration authorities are also recognised
by the VSS. Upon request, the VSS may assist in providing a list of engineering signatories
from other states or territories.

Re: 10kW Motorbike Conversion

Posted: Tue, 07 Aug 2018, 17:46
by moestrei
Thanks for your reply,
Hi Martin,
The motor on the swingarm is a well travelled route. If you can make it fit I think it will work quite well.
I
It fits OK.
The battery though - a little bulky for the energy stored, but the right price I guess.
I wanted a Lithium battery and being in regional NSW a range to get to surrounding towns and back.
I also compared the capacity (6.5kWh) with other e-bikes like the Zero and I think I am not too far off the mark.
Back then when I bought it the battery was around $4k....not that cheap.
The bike has a full fairing which I have widened a bit and I also hollowed out the tank so I am fairly OK with design space.
However I have not done a final drawing as I am still fiddeling with the position of the motor.
Otherwise you could go for a 10 kW hub motor and that would free up a lot more room for batteries in the chassis.
Back then when I purchased all the components there was no 10kW motor available....at least I could not find one.
It would have been my preferred solution by far....perhaps you can point me at something suitable?

I hope there will be a NSW member who can chime in about RTA certification and approval.
It is the RMS Road and Maritime Services nowdays......I hope so too.

Re: 10kW Motorbike Conversion

Posted: Tue, 07 Aug 2018, 17:47
by moestrei
antiscab wrote:
Mon, 06 Aug 2018, 21:56
I was under the impression the certifying engineer just had to be a full member of engineers Australia?

Could you not just sign it off yourself?
No, I cant.....RMS has a list of certified engineers....trick is to find the right one !

Re: 10kW Motorbike Conversion

Posted: Tue, 07 Aug 2018, 17:52
by jonescg
https://www.qs-motor.com/product/new-10 ... -0x17-rim/

Might be a good place to start. Seems like the voltage range is compatible too?

Re: 10kW Motorbike Conversion

Posted: Fri, 10 Aug 2018, 05:32
by moestrei
jonescg wrote:
Tue, 07 Aug 2018, 17:52
https://www.qs-motor.com/product/new-10 ... -0x17-rim/

Might be a good place to start. Seems like the voltage range is compatible too?
Thanks man!
They did not have a 10kW hub motor in a 16 inch rim but an 8kW which I have now ordered in a kit together with a complete rear brake system and a Kelly sine wave controller. It was too convincing space and simplicity wise to not go for it.

So it is now an 8kW conversion only, all your fault :D

Re: 10kW Motorbike Conversion

Posted: Fri, 10 Aug 2018, 09:04
by mikedufty
Why not get the 17" rim? it would probably get you a better selection of tyres too. Shouldn't be any problem fitting as the 17" tyres are generally lower profile.

Edit - I see from the ad it is actually a really wide 17" rim, so may have problems fitting in an older 250.

Re: 10kW Motorbike Conversion

Posted: Fri, 10 Aug 2018, 11:50
by moestrei
mikedufty wrote:
Fri, 10 Aug 2018, 09:04
Why not get the 17" rim? it would probably get you a better selection of tyres too. Shouldn't be any problem fitting as the 17" tyres are generally lower profile.

Edit - I see from the ad it is actually a really wide 17" rim, so may have problems fitting in an older 250.
Also the 10kW was just a bit too wide for the swing arm whilst the 8kW fits spot on.

If end up with a top speed of 110-120km/h that would be OK, cruising from A to B would be on 80-90km/h.

Re: 10kW Motorbike Conversion

Posted: Fri, 10 Aug 2018, 11:57
by antiscab
Top speed would be fairly short lived due to heat buildup. My Vectrix draws 10kw to do 100 -110kmh.

Tricky part is you don't really know until after its built and you've tested it

Re: 10kW Motorbike Conversion

Posted: Fri, 10 Aug 2018, 15:10
by jonescg
My 4 kW scooter does 70 km/h, and that's honkin' on bobo. So 8 kW should manage 100 km/h (eventually).

Re: 10kW now 8kw Motorbike Conversion

Posted: Fri, 10 Aug 2018, 17:09
by moestrei
jonescg wrote:
Fri, 10 Aug 2018, 15:10
My 4 kW scooter does 70 km/h, and that's honkin' on bobo. So 8 kW should manage 100 km/h (eventually).
See, it all depends on factors like weight and aerodynamics: I have a mountain bike (with street tires) with a 1.5kW motor doing 65Km/h with me (105Kg) folded flat on the bike.

The 250 Kawasaki is a small and lightweight bike with a full fairing so I think it will go OK.
The manufacturer of the hub motor recons 110-120km/h should be possible.
I know of an existing conversion using the 10kW motor I had originally and the owner (Italian guy.....I know from my 850 Moto Guzzi that they are very optimistic) claimed a top speed of 145 Km/h.

Time will tell....So back to the original question for you NSW people:
Is there such a silence because no one had made any positive experiences with RMS certifying engineers?

Re: 10kW Motorbike Conversion

Posted: Tue, 27 Nov 2018, 08:39
by soyachips
Hi Martin,

Did you manage to find a certifying engineer? I'm thinking of doing a motorbike conversion but want to check what's possible before buying a donor chassis.

Thanks!
Andrew