Wondering about the front suspension forks on e-bikes

TimJohn

Active Member
A question...are the front suspension on e-bikes hydraulic and springs or just springs? Are both front units suspended with a hydraulic oil inside them and what would be the maintenance.

I am assuming the suspension system is just like the motorcycle suspension so there is a damping of the springs. Are all front end suspension units on e-bikes designed this way?
 

rich c

Well-Known Member
Since there are hundreds of eBike models, you can't generalize with styles of forks. One of my Haibikes is air suspension, the second one is spring. I'm not knowledgeable enough to know if there are any hydraulic forks.
 

Alaskan

Well-Known Member
Fluids do not compress so shocks use either springs or pneumatics (weight based variable compressed air springs)
 

marcparnes

New Member
Fluids do not compress so shocks use either springs or pneumatics (weight based variable compressed air springs)
Front and rear suspension uses oil as a damping medium. Springs and air are used to support the bike while the internal damper valving controls rebound and compression. If you do a Google search you'll find many articles that go into more detail. Here is a link that discusses MB suspension.

Marc
 

Alaskan

Well-Known Member
Precisely. Oil is used for damping because it does not compress. This is why fluid drive systems are so positive, strong and compact.
 

TimJohn

Active Member
All M/C suspension front ends use oil and have complex damping mechanism built into the down tubes. I know, I just replaced the fork seals on my Suzuki M/C. There are orifices and damping oil along with a spring and I wonder if e-bikes are the same.

Does the oil in the front end of a Hiabike or any other e-bike require changing or maintenance like a M/C? Thats my question. Any e-bike service guys here?
 

sl_duck

Member
Yes, it does. Suntour recommends servicing the internals every 500hrs. Damping is the same idea as motorcycle forks for the higher quality bike forks. Generally the more you pay, the more adjustments you'll have for compression, rebound, preload, linearity, lock-out etc.
 

Over50

Well-Known Member
Yes, it does. Suntour recommends servicing the internals every 500hrs. Damping is the same idea as motorcycle forks for the higher quality bike forks. Generally the more you pay, the more adjustments you'll have for compression, rebound, preload, linearity, lock-out etc.
My LBS mentioned the same 500 hr figure to me but they also said it is recommended that the fork manufacturer perform the servicing (has to be shipped obviously). I asked them if this was a recommendation based on off-road usage but they didn't seem sure. I would think for on-road, as my bikes are mainly used for commuting, the interval would be greater. I'm not sure how else to maintain my forks but I occasionally turn the bikes upside down (think I saw this on a Youtube video), I keep the stanchions clean and check my air pressure. Anything else an owner can do short of a full service?
 

JayVee

Well-Known Member
IMO there will be literally dozens of other tasks that need to be done before the shocks need any maintenance.

A sample of what I've had to do over about 23,000 kilometers:

- Change the discs
- Change pads
- Change the cassette
- Change the derailleur jockey wheels
- Change the derailleur cable
- Swap out a broken electrical control pad
- Change the front chainrings
- Fix a wobbly front fender
- Burp the brakes & replenish the brake fluid
- Tighten and lube the motor bolts
- Replace a broken rear wheel (hub was defective).
- Change worn tires.
- Fix return springs in the brake levers
- Fix the battery's rubber seal for the charger plug
- Fix the charger (wires starting to come apart)
- Center brake calipers

And there are probably a couple of other things I had to do which I can't remember. Front shocks are untouched, but to be fair they are the simpler mechanical spring type.