The cheapest way to get speed

[veloman]

I'm not sure everyone is aware of this. But your aerodynamics play a huge role in your cruising and top speed. Small things like taking off that long sleeve button down shirt and wearing a close fitting t-shirt will add 5-10% to your speed. Same with pants, any casual clothing is like a parachute.

Riding with one hand (when safe), and tucking the other arm in, and aerotucking your torso will add another 5-10%.

I'm about to put a foot platform in my front triangle of the frame so I can get my legs up higher. In combination with the above, I will realize some significant free speed.

When you let off the throttle, you shouldn't be feeling like your tires are stuck to the ground. After years of road cycling, I've really developed an appreciation for aerodynamics.

While rounding a turn going into the parking garage at work today, I hit this massive wall of wind, which nearly stopped me. Much of that is due to my baggy casual work clothes. Tonight I took the ebike out for a joy ride in a small t-shirt and gym shorts. It was really windy and I felt much much less of the headwinds pulling me down.

 

[dequinox]

Yes tucking and tighter clothing help. The best thing is lycra...there are those of us who don't go there out of principal or discomfort...


and then there are those of us for whom it's not an option. Apparently this guy missed that memo...

 

[veloman]

Hey, do you have a thread on your ebike build? I'm using the same motor, with a chain drive, for my 3rd build.

any pics?


lol and yeah, about the spandex thing. My skinsuit for road racing is even 1-2mph faster than my normal jersey at racing speed.

 

[AussieJester]

Apparently this guy missed that memo...

^^isn't that Morph?^^ !?@#!? :lol:

KiM

 

[REdiculous]

For sure...agree 110%. The next-cheapest speed/efficiency increase might come from skinny tires w/ proper pressure.

 

[John in CR]

Veloman,

You'll have me breaking 70mph without changing much of anything on my bike with all these 5-10%'s. I ride a fast and powerful ebike with lots of batteries so I don't have to worry about that stuff. That said, I do have some long slight inclines on my some of my usual routes, so when I hit a big headwind that slows me down more than I like, I do tuck and go one handed quite often. I also trimmed 1.5" off of each side of my handlebars recently, giving me a bit narrower profile to the wind, as well as a bit more clearance squeezing between cars.

New clothes and tires??? Sorry but a new controller and more batteries is probably cheaper and more effective.

 

[icecube57]

I had 1.95 knobbies stock on my bike. I switched to 1.75 Urban Street style tires made by Bell and I pump between 50-60 psi. I had a 3-5mph gain. It handles really well. Currently running 60v20AH. The bike is solid and rides like a motorcycle. Cant wait to get my balance connetors in so I can set up my pack for 72v 20AH. I can aout 5mph tucking in. But I have alot of weight with me and my battery pack and suck but when you hav a 1.5kw pack is wind really a issue at that point.

 

[veloman]

Well some of us don't want to spend $800 on batteries now, lol. My current bike has a 450watt motor and my battery pack is 220wh Konion. So I'm aiming for efficiency! To me, tucking in is the difference between 21mph and 23-24mph, so it's definitely worth it.

The goal I look to is 500watts at 30mph, that's what a road cyclist in a good position will have to put out for that speed. Rolling resistence will never be as good on an ebike, with all the extra weight adding to it. But since I'm not pedaling, I am able to really tuck myself in quite well, and that can possibly bring me in closer to that goal.

I tired 1.5" tires at 65psi, and did coast down tests, comparing them to fast rolling mtn bike 2" tires. There was no difference or benefit to gain with the skinny tires. Those skinny tires really made me worried about flats and poor cornering ability. I think at ebike weights, above 50lbs (mines right at 50), skinny tires lose their advantage. My road bike obviously rolls faster with the 120psi 1" tires, but it's a horribly rough ride that I would never want on an ebike.

I'll look into the tire issue more. I know that pedaling typical mtn bike with knobbies at 20-30psi is like molasses compared to high pressure slicks. But it's hard to tell the difference on the ebike.

My current rear tire is a Continental CountryRide 1.75 slick center tread. It gives very good handling over less than perfect roads and still rolls decent. There's lot of chip seal around here in Austin TX and I have to ride through a dirt/gravel lot going to work everyday. So I put on a 2" knobbie tire on the front, but the center treads almost form a complete slick pattern and it does feel like it rolls well at 60psi. Handling on dirt is soo much safer with that tire, and I never worry about flats.

If you somehow have a < 40lb ebike, then you can probably get away with high pressure 1.25" slicks. Full suspension would help there a lot too. But most of you are riding 60+ lb bikes, right?

 

[BiGH]

welcome to lycra.

 

[PedalingBiped]

It's not the Lycra. He said in an interview that he attributes his first place finish to shaving his legs!!!

 

[Mark_A_W]

In my experience, at around 50kmh, tucking and lycra make basically no significant difference to the speed, or watts to maintain that speed.


All the real drag seems to be from the bike itself.


I wear lycra because I sweat, because I pedal....and it helps a little bit when you are sliding along the road at 40kmh...only the impact point and pressure points get worn through..


Tyre pressure does make a difference. I run my hookworms at 65 psi.

 

[John in CR]

Veloman,
You're just killing your cells more quickly with that small pack. Make your batteries happy and let them breed and multiply. Also, ebikes are for riding not carrying, so it's time to get over the weight fixation. Do you buy a car based on how much it weighs?

Mark_A_W,
You've floored me before, but this one takes the cake. You must have some kind of odd non-aero tuck for it not to make any difference, though 30mph is on the low side for readily feeling the benefits of better aero.

 

[Mark_A_W]

I just tested it on the way home.

No real difference.


I do have a backpack on.


But I do realise the effect is huge - also on the way home I trailed a truck, cruising at 45kmh for ages....no motor, with my 36kg bike, which is a pig to pedal.


It's the bike, not my upper body position, which causes most of the drag.

 

[dogman dan]

Yeah, tucking with a backpack would be pointless. Aero matters. I rode a honda 125 for years back in the 55 mph speed limit days. It would keep up with cars going 64 mph on the freeway only if I got into the best possible tuck, laying on the tank, feet on the rear pegs, and one hand. But with a pack on, the tuck had no effect, since laying down simply exposed the pack to the stream of air.

Due to the exponetial nature of it, areo will matter a lot more at 30 mph than it does at 20. Ebikes are notoriously un aero though, with battery stuck on every where etc.

 

[REdiculous]

I'm running a 20x1 3/8" front and 20x1.5" rear and it's amazing how far I can coast with a bit of tucking. I grew up on knobby 1.75" and larger tires so the difference is huge to me.

The benefits are enough (imo) to outweigh the harsher ride..I've never had a suspension frame anyway, what's comfort? If racers can handle 10-speed tires..

I dunno, my case is probably different since the weight isn't really on the bike. I'll never go back tho..1.5" maximum.

 

[zilla]

500W @ 50KPH/30MPH?

done on this with very light pedaling cycle annalist showing 467w in a comfortable riding position
e bikes can be light (16.7 kg) and aero

 

[John in CR]

That bike looks like it might go faster with no motor.

 

[Little-Acorn]

The cheapest way to get speed

Two words:

GASOLINE ENGINE.

 

[dogman dan]

Yeah, that's why I own a chinese 150cc scooter as well as the ebikes. Any day I'm running late, can be a scooter day, and 60mph to work.

 

[geekybiker]

I'll look into the tire issue more. I know that pedaling typical mtn bike with knobbies at 20-30psi is like molasses compared to high pressure slicks. But it's hard to tell the difference on the ebike.

I bet your battery can tell the difference if you look at your logs.

 

[John in CR]

The cheapest way to get speed

Two words:

GASOLINE ENGINE.

Sorry, but a gas engine is more expensive than more batteries and a new controller. Plus my ebikes will be slaughtering gassers that cost up to at least double in the near future. The only thing a gasser will have no me is range and refueling time. I'm obviously not talking about sports bikes, but with comparable cost, even then I believe I could keep up except in the range department.

 

[BiGH]

The cheapest way to get speed

Two words:

GASOLINE ENGINE.

Sadly I agree, its the cheapest initial way... slap a 80hp gas motor on your bike.
Its also the smelliest grossest way

If you really must get a scooter I'd reccomend a vectrix (as long as it has enough range for you). I'm strongly considering one, but want to build my car first. I've ridden one and LOVED it. They're only $3500 AUD on ebay, so thats pretty good!

I also find that with traffic and working in the city, car is the slowest way to get to work. heck for me road cycling even beats the train.

car = 1.5 hours (cost of parking is massive)
train = car to station (10 min) + walk from car to platform(5-10 mins) + train to work 45mins + walk a block (5 mins) = 1 hr 10 (to ensure i'm at work on time)
road bike = 1hr 7mins+ shower
ebike = 50min - 1 hr + shower (i peddle too)

shower takes time, but if i didn't ride, i'd have to do that at home. The road bike will take less time as I get fitter (i'm a bit out of shape atm)

 

[veloman]

John,

You have a point. At the moment, I doubt my 450w motor is stressing my 3 pack. The highest peak amps I've pulled were 22amps, usually around 18amps the highest when climbing. That's 3c.....

But since I am trying to build up a new bike with a 1000w motor, I will have to go to 4 or 5 packs as you say.

I like the lightweight of my bike right now, it handles nice at 50lbs. Once I get my 1000w build I won't be as hesitant to put more weight on it since it will handle the hills much better.

For a modification of my current 36v system.... could 4 12ah SLAs handle 40amps discharge? LOL, prob not a good idea.... but it'd be the easiest way to overvolt my new motor. I also thought of doing a dual 1000w motor setup like on that cyclone site. But with #25 chain since my currie motors already have that freewheel sprocket on them.


Ahhh, I have soo many build ideas right now, I don't know what to do.