waynebergman said:
I want to treat my HS3540 nicely and not abuse it when climbing and give it proper cool down time if it gets hot. I only have all my components for the build at this point (wont be able to start the build for a few weeks) but wanting to be prepared for the big day when I actually hit the trail with the bike. I have been doing some experimenting with the simulator from grin tech to get a feel for what I can get by with on 18% grades with different throttle settings before I would overheat the motor. Getting a bit of an understanding as to what to expect but I have a few questions for those that have this motor and how they treat the overheating issues and the management of range.
1. It seems using the simulator that if I am going up a steep hill at full throttle I will get better range than if I am using very little throttle. If I am only using very little throttle so slow speed the range really seems to get wacked. If throttle is backed of on the flats the range is increased not decreased so I am guessing the motor is not happy climbing steeper grades if it is not given close to full power...........is this correct?
2.Is there a good way when you are out on the road or trail to know if you are getting close to overheating. I have an infrared thermometer that can give temp readings off of surfaces for my pizza oven, would something like this work at all for getting temp feedback from outer casing on the hub motor?
3.Is there kind of a formula for resting the bike to cool things off. Lets say I have been climbing hard for 5 minutes and think I am close to overheating would a 5 minute rest cool things down enough to carrry on? Or would it be better to say keep the motor working and the bike moving say on a flat grade to cool it off rather than just stopping and waiting for cool down?
Also just so you know my set up..............HS3540, 35 A controller, 48v 20ah 50a Samsung Lith Manganeze Battery pack, 24 inch rear wheel, Team Giant DH Bike, and rider @ 135lbs. (I think the whole bike with rider and battery and motor will weigh in around 210lbs.)
Thanks for this.............wayne
Ive got a ht myself, so its not so much of an amp whore as the hs, but ill try and answer as best I can...
If things are getting too hot, stop. to some extent you'll get 'faster' cooling if your moving at a decent speed on the flats, but the fact is some small% of the power will still be going to generate heat, and if your close to burning something its safer to stop and wait.
your hand is a pretty good temp guide too - but if the themomiter is easy to carry then its worth taking allong. the main thing to think about with a sealed motor is that the windings are going to be notably hotter than the outer casing. you can see this when you stop riding for a while, the temp on the casing will jump by a few degrees in the first few minutes as its no longer beeing cooled by the rush of air (from you moving) but is still being heated from the still hot windings. The bigger and faster the jump in the temprature after you stop, the hotter your windings were (compared to your casing). To give you a starting point, after a 20km ride with some decent hills and me pedaling a bit too I see the temps jump by a max of 5-7 deg after about 3-5 minutes, before it begins to drop off again. The hottest Ive had so far was 47degC. I haven't opened my motor yet, but going on what others have said I'd be surprised if my motor is anywhere near overheating. Ive seen some people saying their casing was at 120deg when they burnt their motor
and others that have been fine with temps of 65deg.
And to answer your first question, I think this would be because at partial throttle your motor will struggle to get into its efficient range on a steep grade compared to wot, as it simply doesn't have the power to do it. the efficiency curve at partial throttle is much sharper too, so a small difference in speed makes a big difference in efficiency. Added to all this is peak efficiency at partial throttle will be a bit lower too, and its harder on your controller. Thats not to say go WOT up every hill though. the best is if you can pedal with the bike and put in enough to get it further into that 'peak' efficiency. that way the motor 'feels' like its running on the flat, or atleast a lesser grade hill, and will generate less heat as a result. Harder work on the legs though.
The 24" will help a bit, as will your weight (im about 200lbs, bike is close to 80). But mainly, ride conservatively for the first few weeks, checking the temp regularly, you'll eventually get a feel for it. and keep mesuring the temp rise after you stop riding, that too will start to give you an idea how much your pushing it...
Anyone with more knowhow than mme feel free to correct me here though, im only going on my six months of experience and the ebikesca simulator.
ps
18% grade is huge. most people would have a hard time pedalling up a 10% grade for any length of time, and most roads are less than ~7. And sorry for the long winded explanation. Im burnt out from study for exams and Im rambling like someone 3x my age
I would like to calculate the spoke length for ordering the spokes already now 
. I cannot find this in the Crystalyte specs nor somewhere in this interesting thread and my two motors (HS and HT) are still on their way to me for another fortnight.
!
I will do the mod if I get the old versions.
