once you get much over 30 to 35 mph on a bike, the wind drag becomes THE major thing. Swept area, wind coefficient, etc, energy goes up by a factor of 4, so at high speeds, just an extra 5 mph might take 50 hp.
if you can, get on a highway early / late when there is not a lot of traffic, set your speed to 70 mph / 100 ish kmh sit straight up and watch your power consumption for a mile or so, now do a good race tuck and watch how much that can go down. yes, even just your body sticking up causes THAT much drag.
another interesting thing, as you heat the battery up, get it into the yellow, the range goes up significantly on it. The chemical action etc etc.
yesterday i did a 285 mile round trip on my ribelle across north / ne florida hitting a shit ton of charging stations seeing which ones work, don't work, having fun... just a fun day out.
getting on some of those back country highways / roads with no traffic. ooh yah i lit her up. did some back to back to back charge / discharge cycles. i finally started hitting some charge current limiting at a battery temp of about 45 C ish, it took me down to about 45 amps.. this caused the battery to rise in temp a bit from charging to about 50c which limited my charging to worst case about 32 amps. this mainly i believe was because the bike was sitting in the hot ass sun with zero breeze on the battery to remove any heat.
got back on the road and did an extended romp. this time on the interstate which amazingly had very light traffic. ironically the air flow was enough to actually cool the battery down a bit until i started coming over 100 ish. at about 110 sustained for 5 minutes or so, battery temp started climbing slightly again. i found it interesting that the air flow could keep the battery cool even at elevated speeds. i also found that my range jumped significantly too. i had one run that was 32 miles, varying speeds, only slowing really when i had to or, when the creep got me in the 120 range and i really needed to slow down to not super suck the battery. elevated speed, i was expecting battery drain to be 50 to 60 percent. i was testing if i could 'have fun' between 2 charging stations, and not have to worry about percent left if one was closed and i had to run the additonal 12 miles to hit another station that worked for me. i ended up with 38 percent suck down which frankly stunned me. earlier 'romps in the hay' with battery temps much lower, slorped it down pretty hard at those speeds.. well maybe 20 mph faster but still. the efficiency really surprised me. Total disclosure though i was purposely trying to minimize battery drain, and was in a full race tuck hiding behind the wind screen as much as i could. At those speeds the wind can start causing problems and i try to stay out of it if i can.
anyways, battery range, you can do a lot to change it, and yes, there really should be like an iso standard or something on how that is determined. i am sure there is some standard there already but the manip can be huge, they need a lot more disclosure on how they ran it.
as for ice and efficiency. not entirely sure for just bikes. i have a chevy silverado and when doing 65 mph can get about 14 mpg maybe 15 now when i push that up to say 90 mph i can get 18 to sometimes 20 mpg. the aero on that thing is horrid, the front is a wall really. loading that big ass v8 up yes i can see where the efficiency may come up a bit. as another side note, trees lining the highway even though they are what 100 feet back from the road, in the everglades.. but having a solid line of trees to break the wind can have a huge impact too, for whatever reasons, towing my trailer i can go from 10 to 11 mpg to 14 ish just by getting into the treed off zones. not sure how that would affect a bike, i might have to make a run to orlando and do some investimugatin
Dainese is down there and i need to reset the airbag on my one suit i finally got fixed at a steal of a deal... hmm maybe next week if weather is nice.
anyways, some of those big claims, they possibly may have done it, but there is so much manip that can be done to a vehicle to make the claims,.. there really needs to be a much higher standard of controls or much better disclosure of a LOT of parameters when they give their numbers. and NO a dyno can NOT replicate real life very well even with a wind tunnel. i want real life numbers, not fudge numbers
aaron
Author
Topic: Motobob on the WN7 (Read 111884 times)