Wrestling with the NuVinci

I’ve psyched myself up looking forward to the first ride on the refurbed city beater sporting its shiny NuVinci hub but it looks like I’ll have to satisfy myself with visualization exercises a little longer.

The idea was to give the old horse a new lease on life and get some experience with the NuVinci by ditching the spastic derailleurs. Besides fewer knees smashing into the steering stem due to spontaneously shifting gears, I liked the idea of fewer components and cables to maintain. The only caveat? The old Giant ATX770 frame has vertical dropouts, not the horizontal type for which the NuVinci was designed. To the rescue were little idler pulleys like thisThe answer...for about 2 minutes

that are designed to maintain chain tension in exactly this type of situation. The NuVinci introduces an unfortunate complication in that the rear pulley housing demands real estate already occupied by the idler pulley.

Problems even a Dremel can't solveThe picture makes it look like a little grinding might do the trick but what you see there is just the nut, the actual housing takes up another 6mm or so radially. Could this be the end of the line for the old steel frame as it’s cast aside in favor of a nifty aluminum number with dropouts pointing the right direction? Or will it soldier on with a new set of derailleurs lifted from the bottom of the closeout bin? Watch the craigslist classifieds for the exciting conclusion!

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Electric MR2 hits the road!

…this should have been posted back in mid-November when it actually happened, but who wants to sit at a computer when you could be playing with your new toy – before it gets cold out.

Almost exactly 18 months after it went up on jackstands, the electrified MR2 was run around the block and then some. It would have been nice if, in my haste, an improperly placed jack stand didn’t crack some of the plastic side skirting but at least it’s only visible from the underside.

At first it was a dog and I couldn’t figure out why until I flipped dsc00138-1.jpgthe low power switch off, then it scooted away nicely. I think it’s as quick as stock but it’s hard to tell as I haven’t timed it and accelerating feels different, more of a steady push in the back than quick rushes. It got to 45 in about a suburban block. It’s down while I attend to a few old car issues to make it inspection ready but I’ll have better numbers in a few weeks.

More technical information can be found on the EVAlbum here but a quick summary follows: It uses a Siemens 100kW AC motor and 264V of AGM batteries (that’s all I could fit within weight and packaging parameters) and transfers power through the stock transmission kept in 2nd gear. Ceramic heater and on-board Brusa charger. On paper it should have a 40 mile range but I need to spend a few weeks breaking in the batteries, tweaking the alignment, adding an undertray, adjusting driving style and regen, etc before I find out if that number’s realistic. The estimate is based on the high end of the 180-250 Wh/mi energy consumption number taken from others using a similar inverter/motor and vehicle size. Kokam LiPo battery donations kindly accepted!

I’m very happy that I can now cover reasonable distances without using oil. I ride my bike most places but now I can run longer distance errands while passing by the gas stations.

More pictures, movies and driving impressions to follow.

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Meeting with Maini

One of the highlights of my three weeks spent in India was visiting Dr. Sudarshan Maini, founder of the Maini Group that produces the Reva electric car. His residence is a few floors above the Reva showroom in Bangalore. The showroom area was under renovation but there were several models, including the new i, outside to examine. More about the Reva in another post…

As I walked into his meeting room, my first impression was how dsc00564.jpggracious and welcoming Dr. Maini was. I wasn’t sure what to expect but I immediately felt at ease. The following 20 minutes was filled with EV talk and the future of the business both for Reva and myself. Some interesting points were:

-No indigenous EV-suitable advanced battery technology on the horizon.
-They have built a supplier network and all the major components are now indigenously sourced.
-They’re tooling up a factory capable of 30,000 units/yr, but not the current model. My guess is that they are manufacturing for Tata who has announced an EV for foreign (European mostly) markets in the next few years.

I asked about building an electric autorickshaw to replace the smoky and noisy gas powered units that belch their way all around India but he mentioned their reticence at entering a market that an industrial power like Bajaj totally dominates. I had to admit some disappointment that such a huge opportunity couldn’t be taken advantage of in order to avoid political ramifications. The same story seems to play out everywhere. Disruptive technology in an industry as capital intensive as automobiles is not welcomed.

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