Belts also consume less power when they warm up. My first car was the original Variomatic from DAF, using a belt transmission that ran between the two sides of two pulley halves which could move and thereby change the radius where the belt engaged, thereby changing the ratio of the transmission (it used a combination of motor vacuum and centrifugal weights to vary the gearing ratio. This was the origin of the continuous variable transmission, released in early '60s Daffodil cars, I had the last of the line - a DAF 46 (using only 1 belt and a diff instead of independent rear wheel drive using 2 belts, which made the car a favorite in ralley racing)
On my longer drives I really noticed that after a while on the freeway, the top speed increased due to the belt siphoning off less power from the anemic 800cc 2-cyl boxer motor. Cor van de Water Chief Scientist Proxim Wireless Corporation http://www.proxim.com Email: [email protected] Private: http://www.cvandewater.info Skype: cor_van_de_water Tel: +1 408 383 7626 -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Michael K Johnson Sent: Saturday, March 01, 2014 3:41 PM To: Electric Vehicle Discussion List Subject: [EVDL] MTD Conversion: Success? http://www.evalbum.com/4841 I mowed today (though only leaves, as a test; the grass hasn't started growing). Thanks everyone here who gave me advice. I'm still learning, and I still have work to do for some small improvements, but I'm to the point of being able to mow the lawn when the grass starts growing in the next few weeks. Since I searched before I started for conversion stories of MTD mowers, I wanted to at least provide an update for whoever becomes interested in this next. I asked earlier about battery voltages. I don't own a fluke (yet...) but I borrowed one and compared it to my meter across a wide range of stable voltages within the 4V-40V range, and found that my meter reads consistently low by 0.7-0.8%; this means that in the range of 13V it's precisely 0.1V low which I can now account for and both be sure I'm not cooking a battery while charging and confidently measure state of charge. (I'm using http://www.energymatters.com.au/renewable-energy/batteries/battery-volta ge-discharge.phpas my source of state of charge voltages for AGM batteries as I haven't found similar information that is specific to Deka) My plan to use fans to pull air through a reticulated filter-so that the engine is in clean air-was responsible for about half my build time as I kept trying out different ideas. I ended up with three sides of the box plexiglas to show off the motor, contactor, and shunt. My test mowing leaves through up a lot of dust and the filter clearly worked; I could see where each of the 4 box fans underneath the foam was running. I'm currently drawing around 150A with both the mower deck and transmission engaged. Unless the current draw becomes significantly lower after a few hours of operation and the new belts limber up considerably, I guess I'll likely be lurking on craigslist looking for a glider that either has a true hydrostatic transmission (in which case I won't need to add a motor controller) or a geared drive (in which case I'll obviously need a motor controller). -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140301/0b79 bfb0/attachment.htm> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA) _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
