Tire pressure is an important consideration. I have a theory that says that the tire pressure should be slightly less than the pressure that it takes to deform the surface the tire is rolling over since it takes more energy to deform most surfaces than to deform the tire.
Some think that by increasing tire pressure that I reduce traction due to less surface area on the road. Well, in some situation maybe yes, but no. The coefficient of friction between two give materials is a constant. In a low tire pressure situation there is greater surface area in contact with the road at a lower pressure. In a high tire pressure situation there is less surface area in contact with the road but at a higher pressure. I've not done that analysis but I believe that the amount of force it takes to break traction is basically the same for both situations. I run 115 psi in my road bike tires, 43 psi in my car tires, 7psi in my electric ATV tires, 25 to 45 psi in my mountain bike tires and 4 to 15 psi in my fatbike tires. My theory seems to hold true when riding the road bike from asphalt to the lawn compared to doing the same on the fatbike. Oh, and both have great traction in both environments. Even when backpacking with my hard soled hiking shoes, walking on the harder part of the trail takes less effort than walking on the soft part of the trail. On Nov 11, 2014, at 4:07 PM, via EV <ev@lists.evdl.org> wrote: > Send EV mailing list submissions to > ev@lists.evdl.org > > To subscribe or unsubscribe via the World Wide Web, visit > http://lists.evdl.org/listinfo.cgi/ev-evdl.org > or, via email, send a message with subject or body 'help' to > ev-requ...@lists.evdl.org > > You can reach the person managing the list at > ev-ow...@lists.evdl.org > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of EV digest..." > > > Also, please be careful not to append the entire digest to your reply. Many > mail systems do this by default. Trim or delete the digest text from the > bottom of your message, and quote only the parts to which you're replying. > > > > Today's Topics: > > 1. Re: Range vs Speed (Michael Ross via EV) > 2. Re: Range vs Speed (Cor van de Water via EV) > 3. Re: New EV trike pickup. (jerry freedomev via EV) > 4. Battery future vid very good (jerry freedomev via EV) > 5. EVLN and other posts ... (brucedp via EV) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Mon, 10 Nov 2014 16:48:21 -0500 > From: Michael Ross via EV <ev@lists.evdl.org> > To: Lee Hart <leeah...@earthlink.net>, Electric Vehicle Discussion > List <ev@lists.evdl.org> > Subject: Re: [EVDL] Range vs Speed > Message-ID: > <cannqeo+qtbmtvdqce2qb8uc9fz--ewyb5j0t9k-kzwf7oon...@mail.gmail.com> > Content-Type: text/plain; charset="utf-8" > > On a road bike (more efficient than thick tired MTB) bicycle tires are very > thin. There is some heat generated in the rubber itself from weighting and > de-weighting and side loads. The molecules are literally sliding across > each other, unwinding and winding back up. Heat results. The fabric > carcass also has some flexing and sliding around. Heat results. > > Because the bike is human powered weight is measured out in grams instead > of kilos or pounds. In particular the rotating bits have inertia to > overcome spinning up - light tires make the bike noticeable more > responsive. > > Pumping the tires up hard reduces the flexing and decreases rolling > resistance. But designing them with less thickness is always better for > efficiency. Harder compounds where there is less internal flow helps too. > > If you could run a tire 1/8 inch thick you would get much better efficiency > from it. > > On Mon, Nov 10, 2014 at 1:56 PM, Lee Hart via EV <ev@lists.evdl.org> wrote: > >> jerry freedomev via EV wrote: >> >>> Hi Lee and All, I'm using some early Mazda Miata front hubs, brakes >>> that has retraction V shaped springs that with just a couple tiny >>> holes drilled in the pad for the wire spring end to fit, could fit >>> many disc brakes that don't have them stock. Likely able to do it >>> with just removing the tire. >>> >> >> That's a great idea. I'll have to look into that. My LeCar EV always has >> dragging brakes. Like many, they depend on the roll-back of the rubber >> piston seals as their "spring" to pull back just a tiny bit. Then the >> calipers are supposed to be floating on pins, so that the slight runout of >> the rotor and play in the wheel bearing are enough to push the pads away >> from the rotor. >> >> It doesn't work. The o-ring pullback is too little, the pad is just loose >> between the piston and rotor (and tends to lay against the spinning rotor), >> and the floating pins always rust up and won't move. >> >> On Tire LRR common car tires are bad but MC tires are 2x's worse I >>> found on my Streamliner MC low CG chassis !! I'll have to find >>> better before doing the EV Streamliner, maybe even adapting LRR car >>> tires if I can't find a LRR MC tire. >>> >> >> I wonder why motorcycle tires are so much worse. Bicycle tires are >> obviously very good. What is different about motorcycle tires. Is there >> some fundamental reason for the higher rolling resistance, or is it just >> that the manufacturers don't bother (and customers don't care)? >> -- >> A designer knows he has achieved perfection not when there is >> nothing left to add, but when there is nothing left to take away. >> -- Antoine de Saint Exupery >> -- >> Lee Hart's EV projects are at http://www.sunrise-ev.com/LeesEVs.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) >> >> > > > -- > Put this question to yourself: should I use everyone else to attain > happiness, or should I help others gain happiness? > *Dalai Lama * > > Tell me what it is you plan to do > With your one wild and precious life? > Mary Oliver, "The summer day." > > To invent, you need a good imagination and a pile of junk. > Thomas A. Edison > <http://www.brainyquote.com/quotes/quotes/t/thomasaed125362.html> > > A public-opinion poll is no substitute for thought. > *Warren Buffet* > > Michael E. Ross > (919) 550-2430 Land > (919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google Phone > (919) 631-1451 Cell > (919) 513-0418 Desk > > michael.e.r...@gmail.com > <michael.e.r...@gmail.com> > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: > <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20141110/88d18b9b/attachment.htm> > > ------------------------------ > > Message: 2 > Date: Mon, 10 Nov 2014 14:03:35 -0800 > From: Cor van de Water via EV <ev@lists.evdl.org> > To: "Electric Vehicle Discussion List" <ev@lists.evdl.org> > Subject: Re: [EVDL] Range vs Speed > Message-ID: > <a73bc4b8b3218642a56a2c9eb01b44e0022cc...@exchange.corp.proxim.com> > Content-Type: text/plain; charset="us-ascii" > > That is why *everyone* is always disappointed after installing new > tires, > whether they are LRR or not - the MPG will *always* go down, even if the > spec'ed rolling resistance of the new tires is lower than the previous > tires. Because by the time that the tires are worn they are so much > thinner and stiffer that the actual losses are lower than the newer > (thicker, more flexible) tires. > I noticed the same when replacing my 2002 Prius OE tires with the also > LRR > Sumitomo HTR 200 tires - even while I always pump them to 45+ PSI, the > MPG went down considerably (several MPG) from around 50 to around 47 and > only after they started to age did the MPG go back up again. > (What also helps is that a worn tire is *smaller* so the miles are > indicating high, leading to a larger error in artificially increasing > MPG, so the only real measurement is in the pump data which I > unfortunately do not have). Also, the torque to accelerate the car will > reduce a little bit with smaller tires, but this is unlikely to have a > significant impact. > > Cor van de Water > Chief Scientist > Proxim Wireless Corporation http://www.proxim.com > Email: cwa...@proxim.com Private: http://www.cvandewater.info > Skype: cor_van_de_water Tel: +1 408 383 7626 > > > -----Original Message----- > From: EV [mailto:ev-boun...@lists.evdl.org] On Behalf Of Michael Ross > via EV > Sent: Monday, November 10, 2014 1:48 PM > To: Lee Hart; Electric Vehicle Discussion List > Subject: Re: [EVDL] Range vs Speed > > On a road bike (more efficient than thick tired MTB) bicycle tires are > very > thin. There is some heat generated in the rubber itself from weighting > and > de-weighting and side loads. The molecules are literally sliding across > each other, unwinding and winding back up. Heat results. The fabric > carcass also has some flexing and sliding around. Heat results. > > Because the bike is human powered weight is measured out in grams > instead > of kilos or pounds. In particular the rotating bits have inertia to > overcome spinning up - light tires make the bike noticeable more > responsive. > > Pumping the tires up hard reduces the flexing and decreases rolling > resistance. But designing them with less thickness is always better for > efficiency. Harder compounds where there is less internal flow helps > too. > > If you could run a tire 1/8 inch thick you would get much better > efficiency > from it. > > On Mon, Nov 10, 2014 at 1:56 PM, Lee Hart via EV <ev@lists.evdl.org> > wrote: > >> jerry freedomev via EV wrote: >> >>> Hi Lee and All, I'm using some early Mazda Miata front hubs, brakes >>> that has retraction V shaped springs that with just a couple tiny >>> holes drilled in the pad for the wire spring end to fit, could fit >>> many disc brakes that don't have them stock. Likely able to do it >>> with just removing the tire. >>> >> >> That's a great idea. I'll have to look into that. My LeCar EV always > has >> dragging brakes. Like many, they depend on the roll-back of the rubber >> piston seals as their "spring" to pull back just a tiny bit. Then the >> calipers are supposed to be floating on pins, so that the slight > runout of >> the rotor and play in the wheel bearing are enough to push the pads > away >> from the rotor. >> >> It doesn't work. The o-ring pullback is too little, the pad is just > loose >> between the piston and rotor (and tends to lay against the spinning > rotor), >> and the floating pins always rust up and won't move. >> >> On Tire LRR common car tires are bad but MC tires are 2x's worse I >>> found on my Streamliner MC low CG chassis !! I'll have to find >>> better before doing the EV Streamliner, maybe even adapting LRR car >>> tires if I can't find a LRR MC tire. >>> >> >> I wonder why motorcycle tires are so much worse. Bicycle tires are >> obviously very good. What is different about motorcycle tires. Is > there >> some fundamental reason for the higher rolling resistance, or is it > just >> that the manufacturers don't bother (and customers don't care)? >> -- >> A designer knows he has achieved perfection not when there is >> nothing left to add, but when there is nothing left to take away. >> -- Antoine de Saint Exupery >> -- >> Lee Hart's EV projects are at http://www.sunrise-ev.com/LeesEVs.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) >> >> > > > -- > Put this question to yourself: should I use everyone else to attain > happiness, or should I help others gain happiness? > *Dalai Lama * > > Tell me what it is you plan to do > With your one wild and precious life? > Mary Oliver, "The summer day." > > To invent, you need a good imagination and a pile of junk. > Thomas A. Edison > <http://www.brainyquote.com/quotes/quotes/t/thomasaed125362.html> > > A public-opinion poll is no substitute for thought. > *Warren Buffet* > > Michael E. Ross > (919) 550-2430 Land > (919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google > Phone > (919) 631-1451 Cell > (919) 513-0418 Desk > > michael.e.r...@gmail.com > <michael.e.r...@gmail.com> > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: > <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20141110/88d1 > 8b9b/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) > > > > ------------------------------ > > Message: 3 > Date: Mon, 10 Nov 2014 22:53:22 +0000 (UTC) > From: jerry freedomev via EV <ev@lists.evdl.org> > To: Lee Hart <leeah...@earthlink.net>, Electric Vehicle Discussion > List <ev@lists.evdl.org> > Subject: Re: [EVDL] New EV trike pickup. > Message-ID: > > <208738817.221339.1415660002172.javamail.ya...@jws10772.mail.gq1.yahoo.com> > > Content-Type: text/plain; charset="utf-8" > > ??????????????? Hi Lee, Cor?and All, > From: Lee Hart <leeah...@earthlink.net> > To: jerry freedomev <freedo...@yahoo.com>; Electric Vehicle Discussion List > <ev@lists.evdl.org> > Sent: Monday, November 10, 2014 2:03 PM > Subject: Re: [EVDL] New EV trike pickup. > > jerry freedomev via EV wrote: >> Hi All, Just got my new EV trike on the road. It >> went together rather fast in just 2 weeks! > > That's great! Got any pictures? I love Jerry's KISS design EVs. > ---------Actually I do but where does one put them up?? I'll send them > directly to you Lee.? Remember it's still getting built. > >> I'll add 2 more 120 amphr 12 deep cycle Johnson Controls sold >> under Duralast brand to the 4 already there > > Probably OK for testing, but I suspect they won't last long. > --------? I've been through a lot of them but these work very nicely at least > in 600lb EV's.? I'm only drawing 30-40 amps so not hard on them.? After 6 > months they are still within?.03 volt from each other.? This is unlike most a > true deep cycle battery. >> I wonder why motorcycle tires are so much worse. Bicycle tires are > obviously very good. What is different about motorcycle tires. Is there > some fundamental reason for the higher rolling resistance, or is it just > that the manufacturers don't bother (and customers don't care)? > ?-----------I think it's mostly the compound of soft?rubber both sticks > better but generates heat.? And far more concerned about the wheel becoming > unstuck than tire drag. And likely why gas MC's get such bad mileage besides > it's terrible aero.???????????? I like older used?LRR car tires as the aged > rubber is like 10-20% better than a new tire. > >> Otherwise contactor controllers have been working fine for me. >> simple, low cost, reliable and easy to repair even roadside. > > Ain't that the truth. :-) They're the simplest kind of controller to > build and service. I have some examples posted on my website at > http://www.sunrise-ev.com/controllers.htm > I also have a pile of surplus contactors that I've acquired over the > years. Contact me offlist if you need some. > --------- Hard to beat them in so many ways. > ?????????????????????????????????? Jerry Dycus? > -- > A designer knows he has achieved perfection not when there is > nothing left to add, but when there is nothing left to take away. > ? ? ? ? -- Antoine de Saint Exupery > -- > Lee Hart's EV projects are at http://www.sunrise-ev.com/LeesEVs.htm > > > > > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: > <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20141110/96012414/attachment.htm> > > ------------------------------ > > Message: 4 > Date: Tue, 11 Nov 2014 00:36:07 +0000 (UTC) > From: jerry freedomev via EV <ev@lists.evdl.org> > To: Electric Vehicle Discussion List <ev@lists.evdl.org> > Subject: [EVDL] Battery future vid very good > Message-ID: > > <966979859.229152.1415666167931.javamail.ya...@jws10791.mail.gq1.yahoo.com> > > Content-Type: text/plain; charset="utf-8" > > ???????????? Hi All,???????????????? I just found this rather long detailed > but worth it easily 26 minute interview with LG, SATKI battery CEO's if you > are interested in that subject.http://www.autoline.tv/show/1833 > ????????? Jerry ycus > ? > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: > <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20141111/d6cd6e9e/attachment.htm> > > ------------------------------ > > Message: 5 > Date: Tue, 11 Nov 2014 02:04:51 -0800 (PST) > From: brucedp via EV <ev@lists.evdl.org> > To: ev@lists.evdl.org > Subject: [EVDL] EVLN and other posts ... > Message-ID: <1415700291514-4672537.p...@n4.nabble.com> > Content-Type: text/plain; charset=us-ascii > > I have EVLN posts queued for posting, but I am going to hold off until I hear > back from our evdl.org system admin on his decision (relating to same) ... > (so it isn't like before, when it may have seemed like I dropped off the > face of the planet, because I was in a VA hospital without Internet access, > or anything). > > Your patience is appreciated :-) > {brucedp.150m.com} > > > > -- > View this message in context: > http://electric-vehicle-discussion-list.413529.n4.nabble.com/EVLN-and-other-posts-tp4672537.html > Sent from the Electric Vehicle Discussion List mailing list archive at > Nabble.com. > > > ------------------------------ > > Subject: Digest Footer > > _______________________________________________ > EV@lists.evdl.org > For general EVDL support, see http://evdl.org/help/ > http://lists.evdl.org/listinfo.cgi/ev-evdl.org > > > ------------------------------ > > End of EV Digest, Vol 25, Issue 19 > ********************************** _______________________________________________ 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)
