Graft EV EO.12


Philip

Philip

Administrator
Staff member
Likes
4,215
Location
Lake Havasu City, AZ
#76 said:
Tell us more.......
Click to expand...
The company's owner is my good buddy. He has been producing EV powertrains for various commercial vehicles for a few years already, and for the last two years this bike, a side-by-side, and a quad have been his projects.

The motorcycle, the quad, and the side-by-side use the same swappable batteries. Lots of different vehicles, but the batteries are the same. Like Ryobi tools.

He is planning to tour with his products and do demo rides some time this spring, hopefully. I will post when I know more.

www.graft-ev.com

Graft | Electric Powersport

Welcome to the only family of electric power bikes, electric ATV and electric UTV with swappable batteries. Our rides are trail-ready from the jump.
www.graft-ev.com www.graft-ev.com
 
A

Azizi

Member
Likes
6
Location
Taiwan
This is Azizi from Graft...

manisse said:
Do you know why they used a 21" rear wheel instead of 18" or 19"?
Click to expand...

The simple answer is better traction and range.

Our EO.12 models are 200mmm travel Ultralight weight Enduro Motorcycles. Our EO.12 factory team model weighs just 50kg/110lbs ready to ride. As such even with a fat old man such as myself, the sidewall of the normal 18 and 19-inch tires was way too stiff even at 0 psi. We were not able to get deformation in the sidewall to flatten out the tread on the ground.

In addition, the larger overall diameter decreases rolling resistance but the big benefit is when riding bowling-ball sizes rocky river beds the wheel doesn't drop into holes as deep. This allows the bike to "glide" over very rocky terrain a bit better due to the wheel size and a lot better due to the weight.

We are developing a taller 300mm travel bike but it will have a lot more power....

These just some of left overs from tires testing...
20230302_120035.jpg
 
Number Six

Number Six

Well-known member
Likes
137
Location
Midwest
Azizi said:
.. the sidewall of the normal 18 and 19-inch tires was way too stiff even at 0 psi. We were not able to get deformation in the sidewall to flatten out the tread on the ground.
Click to expand...

If you ever have occasion to have another go with an 18" wheel ; consider trying the IRC ix09W 'Gekotta' gummy tire.
They are 2 ply, quite light & have far & away the most compliant sidewalls of any knobby or trials tire Ive ever used.
On our full size 2 stroke enduro bikes we typically can run as low as 4-6 psi in conventional knobby tires, but that Gekotta has to be run at 10-12 just to keep the thing from rolling off the rim, & it still grabs everything - it's that soft in both the sidewalls & the crown.
Sure it would have more drag as the contact patch would be on the order of 50% greater, but the grip & forward drive would be .. frightening ! on a small e-bike that only weighs 110lbs.
.
 
M

manisse

Member
Likes
5
Location
Barcelona
Have you in tried mitas terraforce double green stripe? It's a hard enduro extra gummy tyre, super soft compound and sidewalls, in fact in full size dirt bikes they are only used with mousses to prevent punctures and rim damages
 
Philip

Philip

Administrator
Staff member
Likes
4,215
Location
Lake Havasu City, AZ
@Azizi -- Looks like a lot of people will want to have a real motorcycle tire in the rear. If you allow people to specify the rear tire size at ordering, very few will choose 21".

Will an 18" rear tire fit there width-wise to clear the swing arm and the chain?
 
A

Azizi

Member
Likes
6
Location
Taiwan
Philip said:
@Azizi -- Looks like a lot of people will want to have a real motorcycle tire in the rear. If you allow people to specify the rear tire size at ordering, very few will choose 21".

Will an 18" rear tire fit there width-wise to clear the swing arm and the chain?
Click to expand...
It's certainly an option we can offer. I suspect it will add around 7-10 pounds to the weight of the Motorcycle.
 
You must log in or register to reply here.
Top Bottom