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electrician
08 September 2010, 0633
I received this email from TK of EMS:

"I am at the Factory in Thailand now. We are making a run of GPR-S bikes with slightly larger frames to fit larger format batteries and/or higher voltage packs. The seat will be taller, front forks will be black instead of gold and the brakes will be upgraded as well.

Will have some photos in about a week.

We will be putting together a pre order group buy to make these new chassis more affordable for builders.
It is our goal to make the new 2011 street legal rolling chassis with wiring and full dress available for around 1999 USD pre order.

TK"

Richard230
08 September 2010, 0740
That sounds like good news for anyone wanting to build their own EV without having to deal with the hassle of converting an IC bike. The $2K cost is probably not much more than it would cost to purchase an old IC bike, fix up the chassis, brakes, lights, wiring, suspension, tires, etc. It would save all of those hassles and let you concentrate on just the electrical build and installation of components.

electrician
08 September 2010, 1742
That's true. And with the larger frame---more batteries!

EVcycle
08 September 2010, 1836
I have a few extra batteries....and motor...mmmm.... and a controller!

I will have to look into getting one of these.



EV Ed

electrician
23 September 2010, 1217
I was emailed a few pictures of the new 2011 GPR-S street legal rolling chassis. It is larger but looks identical to the old GPR-S chassis. The seat is a 30mm taller and the frame is 12mm wider. Just big enough to hold 96 volts of the LFP40 with out any frame modification. Pictures to follow.

electrician
23 September 2010, 1717
http://www.angelfire.com/trek/adventurebooks/images/Image2.jpg
http://www.angelfire.com/trek/adventurebooks/images/Image3.jpg

http://www.angelfire.com/trek/adventurebooks/images/Image5.jpg
http://www.angelfire.com/trek/adventurebooks/images/Image6.jpg

Richard230
23 September 2010, 1759
It looks good, but they still have to do something about that lower swing arm brace. On my first bike the chain would rub against the brace and on my current 2009 bike the left-side swing arm brace was cutoff to solve that problem. I can't tell if it has been removed on the bike in the photo, but if not it looks like the chain would hit the brace, based upon the large size of the rear sprocket. The ICE (250 Boxer) version of the GPR-S uses a smaller rear sprocket and therefore the chain interference with the brace is not an issue.

__Tango
23 September 2010, 2232
Looks cool. I'd like to see it without the fairings though, to see what the battery space looks like.

markcycle
24 September 2010, 0519
It looks good, but they still have to do something about that lower swing arm brace. On my first bike the chain would rub against the brace and on my current 2009 bike the left-side swing arm brace was cutoff to solve that problem. I can't tell if it has been removed on the bike in the photo, but if not it looks like the chain would hit the brace, based upon the large size of the rear sprocket. The ICE (250 Boxer) version of the GPR-S uses a smaller rear sprocket and therefore the chain interference with the brace is not an issue.

The solution is not to use a chain.

Richard230
24 September 2010, 0738
I have no love of chains either, Mark. Personally, I prefer belt-drive.

Tango, here are three photos of my 24-cell 2009 GPR-S to give you an idea how much room is provided for batteries and equipment with the smaller GPR-S chassis. It would be nice to know what has been enlarged. Apparently the bike is a bit taller. If it was longer in the middle that would also be useful, but I would think just a couple of inches wouldn't help all that much, but maybe it would with a different equipment packaging. You will have to be the judge.

EVcycle
24 September 2010, 0850
Very Nice!!!!

I may have to order one.

electrician
24 September 2010, 1326
Thanks for the pictures. 24 cells of what size battery?

Richard230
24 September 2010, 1448
Thanks for the pictures. 24 cells of what size battery?

The cells are 50 Ah, "Hi Power" brand.

electrician
24 September 2010, 1514
thanks :)
That puts things in perspective for me.
A little extra room will be nice.

harlan
24 September 2010, 2116
I think the changes are to accommodate a slightly larger battery, the 60Ah TS instead of the 40Ah TS, not more cells. More cells would require a different motor and controller as the Etek and Alltrax can barely handle 24 cells as it is. I bet it would be hard to tell the difference from the old model even side by side. The seat height is only an inch higher and the frame a half inch wider.

electrician
25 September 2010, 0558
good to know :)

eronsilva
26 September 2010, 0914
Richard, that is a nice motor mount you devised there. Your byke look neat and cool. Congrats on a job well done!
(I wonder if this special run of frames already include that?)
As for the chain issue, I guess a spring-loaded nylon roller (like the ones used in motocross bykes) would do the trick - although a toothed belt is the best option (I had a suzuki savage 650 and the belt was flawless!).

Richard230
26 September 2010, 1542
My GPR-S was built by Electric Motorsport in January 2010. I bought it as a fully-assembled, DOT-approved, street-legal, production motorcycle from the Electric Green Showroom in San Carlos, California. All I do is plug it in after riding, check the chain tension and the tire air pressure every now and then. A fabricator I am not - although I can bolt things together if provided clear written instructions with lots of pictures.

NonPolluter
29 September 2010, 1944
I have no love of chains either, Mark. Personally, I prefer belt-drive.

.

Check out the numerous postings about belt drive problems with the Ego-II and its plastic sprockets. Many of these boards/forums have disappeared, as the Ego-2 had its heyday around 2004.

NonPolluter
29 September 2010, 1947
(I had a suzuki savage 650 and the belt was flawless!).

What material was the belt sprocket made of? Also, was the belt sealed from grit and water, like the gas scooters?

Richard230
30 September 2010, 0739
Many IC motorcycles are using belt-drive now, such as most HD models, several Japanese bikes and belt drive is even used on the BMW F800S/ST and the F650CS models. They have proven to be very reliable and maintenance free, even though they are not enclosed. Which is not to say that a cheap and unreliable belt-drive system can not be designed and built by a Chinese manufacturer.