Tire pressure, rolling resistance, battery range

[Ravi Kempaiah]

Call me stupid.

During the end of the summer, last autumn and now in winter I got so carried away with my new e-bikes I completely forgot the tires needed occasional pumping up Let us start with a quite funny story though.

When I went to the Specialized dealer to pay for and collect Vado 5.0, finally got onto the saddle and rode out, I felt my new bike was unwilling to accelerate. Before I even rode onto the main street, a glimpse of understanding passed through my mind. I instantly returned to the store.

-- Haven't you forgotten to pump up the tires, have you? -- I joyfully addressed the mechanic. He blushed. -- Yes, I have... I was overexcited with your electric bike and overlooked that, sorry! -- He answered. At that time he pumped the tires up to 4 bar (58 psi) telling me that was not the maximum allowable tire pressure but it would give me comfortable, yet fast ride (he was right).

Recently, I noticed my Lovelec e-bike "slowed down"; the battery range also dropped significantly down. I attributed that to strong headwinds. Out of sudden, my eye caught the long forgotten pump (the one with a manometer) down in the garage. As I am obese, I usually tend to pump tires half bar (7 psi) below their maximum allowable pressure. The manometer readout was 3 bar (43 psi). After resupplying the pressure up to 5.5 bar (80 psi), the Lovelec started rolling fast again, and the battery range improved. (I'm sure the same case is with my Vado now).

Of course, it is unwise to forget about the tire pressure; read the first sentence of this post. Yet, I hear from many sources it makes sense to lower the tire pressure well below the maximum, for example, for smoother ride or for winter riding. Questions:

• If the rider and the bike together are near to the allowable maximum weight, would you ever reduce the tire pressure?
• In justified cases of reducing the tire pressure, how would that affect the speed achieved?
• As above, have you found lower tire pressure reducing battery range?

Discuss.

There is a similar thread discussing tire pressure.

Interesting Video on Tire Pressure

Detailed discussion on tire pressure. I'm no expert. This guy sounds like he has both knowledge and experience.

electricbikereview.com

The video shared by @Bruce Arnold is fascinating:

 

[Stefan Mikes]

I have seen the thread and tried to watch the video Ravi. Too long, couldn't watch. What matters to me is with my weight I inflate the tires half bar less than the maximum and get the benefit of small rolling resistance and sufficient comfort, while the grip seems to be adequate.