High Speed Long Range Advice

[heavylildude]

Hi all,

My name is Chris, I live in Indonesia. I'm currently a regular 15-20km (roundtrip) commuter on a 250w machine. It's a nice small machine, tho kinda slow at times

I'm looking to upgrade my bike to sumthing more powerful, while looking for more range (change job, longer commuting needed). I'll be looking for around 70-80km (50-60 miles) (single trip) and probably aiming at 60kph (35-40mph)?

Recently I got few offering:
1. 60v 1,5kW Hub
2. 60v 700w Mid
3. 48v 1kW Hub

All with 20A LiPO4

Is 40mph - 60miles range possible with any of these setup in real world?

Fortunatelly, I'm living in a country where NO legal rules applied for eBikes, so I'm looking for high speed non pedalling option The downside is the motorcyclist are pretty crazy here, luckily I'm still passing few other expatriate cyclist commuting on daily basis.

I'm yet deciding whether I should get the ebike or join the crazy motorcyclist LOL. I'm still hoping for ebike as my solution, since here you dont need any lisence for ebike, whatever spec you have, compared to regular motorcycle lisence (even its just a moped). Thats another plus for ebike here in this country!

Thanks for any reply

 

[dogman dan]

The battery will be huge, heavy, hard to carry on a bicycle, and costly.

This is just about the point where we say, "get a gas motorcycle, or scooter".

Oh, it's doable, but it's just not easy to go that far, that fast, and even carry the battery on typical bicycles. So the budget to up the speed and distance that much is going to be a lot of money.

That speed takes about 2500-3000w. So That's roughly 6 times the power you use now. It means your battery will drain fast!
That speed will take at least 60wh/mile. So 60x60 is a 3,600 watt hour battery. In a 72v battery, 50 amp hours. That's gigantic, enough battery to run a small car shorter distances.

This size can be carried by stronger motorcycle frames, so basically you need to look into building an electric motorcycle, rather than an electric bike.

The other approach is to forget that much speed. You can do 25 mph for only about 35 wh/mi. Now that makes it a 2000wh battery. Still very big to carry on a typical bike, but possible on a strong enough frame, or by towing a trailer with the battery. Trailering more possible at 25 mph.

 

[heavylildude]

Hi Dogman Dan,

Thank for replying.

Is that in another word you we're saying that those offers wont make it?

A local seller here ask for $800 for 60v 1,5kW with 20A LiPO4, he 'guarantee' a 75+ kph (around 45mph) speed, 70km range. I generally dont buy what he said He cant give any real demo, thats why I'm trying to seek answer to those who are more experienced here..

 

[wesnewell]

The problem with speed is the wind resistance. Cut that down to next to nothing and you can almost triple the range at the same speed. Easy to get 100km on a 20ah 60V battery at 50kph on a wind resistant trike or bike. Check out full recumbent on simulator.
http://www.ebikes.ca/tools/simulator.html

 

[LewTwo]

he 'guarantee' a 75+ kph (around 45mph) speed, 70km range.

Is he willing to wait to collect his payment until after you return from the first 70km trip ?

 

[MadRhino]

he 'guarantee' a 75+ kph (around 45mph) speed, 70km range.

Is he willing to wait to collect his payment until after you return from the first 70km trip ?

Tell the guy that your bank is 35 Km away, and you are going there with the bike to get his money. :wink:

 

[MadRhino]

Seriously, it is feasable but it will be a heavy bike. Prepare to spend on a good frame, top brakes, and some time thinking a neat way to carry a lot of batteries.

 

[Drunkskunk]

As the others have said, it can be done, but normal bike components may not survive it for long. What you are describing is the performance of a 150cc to 250cc motorcycle. While you can build a bicycle that will do it, it will probably be much cheaper and convenient to just buy the motorcycle.

While we love and advocate electric bicycles here on the forum, sometimes they just aren't the right tool for the job. In your case, a motorcycle or scooter will better suit your needs.

 

[dogman dan]

Ahh, the range claim. I work for a company that sells electric bike kits. On their website, we put up expected ranges.

Typical might be 10-40 miles or whatever. 10 miles is the range if you ride the thing full speed. The 40 miles is possible,I proved it myself. But the speed you ride to do that is so slow, it's not much assist. Mostly the bike is doing the range because you are pedaling most of it. You can get 10-20 miles, at a reasonable level of speed and assist. But the max range is not really something you'll do.

Anyway, we put up range as a spread, 10-40. And we list a top speed, say 28 mph. Others just say range 40 miles, top speed 28. The implication is 40 miles AT 28 mph. Ok, not really a lie, but a very misleading statement.

The straight truth is there in the watt hours per mile, or the watt hours per kilometer number. 15 mph (250w) can be 15 wh/mi. 20 mph (400-600w) around 25 wh/mi. 25 mph (800W), more like 35 wh/mi. And 30 mph (1000W) can be 40-60 wh/mi. I'm not sure what 45 mph takes, I'm guessing 90-100wh/mi.

With this number you can tell the range of a given battery by calculating the wh in the battery. 60v 20ah to get watt hours, it's 60x20. 1200wh, not 1500. About 12 miles at 45mph. 80 miles at 15 mph. Range = 12-80 miles.

The end conclusion is that it will take a larger and larger battery, the faster you go. It will be possible to carry 1500-2000wh, and go the speed that will last you the distance. But carrying 3000-4000wh is just too big, too heavy, and too expensive. But if you build an electric motorcycle, the heavier, stronger, frame can carry it. A dead used motorcycle should be fairly affordable, compared to a top of the line full suspension bike.

So we caught this guy on one lie already, The pack is not 1500wh. The range he claims is not a lie, just not at full speed.
The speed. 45 mph on 60v, really? Yes, flip the bike over, give it full throttle. Likely it will spin the wheel at 45 mph. But get on the bike and ride it into the air, and it won't carry you that speed. 35mph more likely.

I'm not saying don't buy it, or don't buy it from him. Just expect your speed to be 30-35 mph, and your range on one battery to be about 20 miles full speed, or less.

If you do go ahead with a bike for travel at about 30 mph, one bit of advice is to build yourself a cargo bike. Get a welder to lengthen a regular bike. then the longer wheelbase will handle speed better, and it will be able to carry more weight in panniers.

Here is one I just built this spring.

Full build thread with pictures here.

http://endless-sphere.com/forums/viewtopic.php?f=6&t=67049

This bike could carry two of those 60v20 ah batteries. The cruiser frames are some of the strongest out there. Because of the two bars on either side of the frame that become the rear stays stiffen it up a lot.

 

[LockH]

A "problem" with "high speeds" perhaps is human reaction times (yours/operator plus others around you). "Oh, officer, I didn't see that new pothole!" "It was dark!" ... etc Suggest Plan B, where trips just take a little longer. Energy costs per distance less at lower speeds (aerodynamics), maintenance less, more time to see new "stuff" around you... and below you.

Have found recumbent three wheels as much more comfy/forgiving than balancing just on two wheels. Slightly heavier vehicle, but rider and gear weights split 3 ways onto wheel contact patches vs two ways. (Think worn cart tracks, streetcar/trolley rails. Plus back rest, and bigger seat than typical "bicycle seat" jammed between yer legs.) Park it, walk away and the darned thing doesn't fall over/need a stand! W/recumbent position, not as far to go re inevitable "tumble to the ground" vs sitting up higher on a bike. (Needs flag on pole re visibility. I currently use two plastic streamers.)

 

[TeePee]

There is now a distributor for Golden Motor in Jakarta. He has stock of MP4. You'll get 45km/hr if you put it on a 26 inch mountainbike or similar and add a 48v pack. Anthon 081310449264.

Putu who runs Bats Bali sells LifePo4 batteries for a decent price (for Indo!). He is a good guy and won't rip you.

Good luck.

Tom

 

[TheBeastie]

I'm looking to upgrade my bike to sumthing more powerful, while looking for more range (change job, longer commuting needed). I'll be looking for around 70-80km (50-60 miles) (single trip) and probably aiming at 60kph (35-40mph)?

Dogman put it in a lot of detail hopefully its not too much to take in, if it is then I like to put it in a single sentence as listed below in my signature..
Speed kills range, there is no way to outrun physics (in case you were wondering).