2

https://whitebikes.com/ax-290-ff-20/b/2461/

This is my bike and I'm planning to use suspension fork on it, I've converted it to ebike. My budget is approximately 100€/120 dollars. Do you have any recommendations what kind of suspension forks I should look at? I've heard that coil forks need less maintenance compared to air ones. I don't ride any hardcore mtb trails etc.

Some that I've looked myself 50-100mm travel ones are these reputable brands?: Morzocchi txc 2 Zoom Vaxa 30 595S

3
  • Not asking for specific models just linked what I've looked up myself. I'm asking in general for recommendations for suspension fork. Also your thread doesn't answer to my question.
    – MT247
    Dec 29, 2020 at 13:01
  • 3
    @Criggie To be fair, the question as currently worded asks what kind of fork, coil vs gas, is best for his needs. The second part asking about brands is likely off topic.
    – Eric S
    Dec 29, 2020 at 13:33
  • I don't think you can a get a new rigid fork worth riding for that amount
    – Paul H
    Dec 30, 2020 at 0:52

3 Answers 3

5

The type of fork you choose will tend to be based on your riding style, budget and what will work on your bike.

It might be good to consider ebike suspension forks

Whilst E-bike forks remain largely the same as their regular counterparts, it’s important to acknowledge that E-bikes are slightly different. E-bike suspension forks are usually designed to provide extra comfort, rather than actual cushioning off-road. Given their intended use, they are often more affordable than regular suspension forks since they feature less complex designs.

bikester.co.uk (not a recommendation for this site or it's products)

Suspension Fork Type - Air vs Coil

Air

Pros:

  1. Generally lighter than coil
  2. Easy to adjust
  3. Especially good for cross country or trial riding

Cons:

  1. Progressive spring rate - the more it is compressed the stiffer it becomes, not as smooth on big hits. This issue has been addressed in some air forks/shocks
  2. Stiction - the force needed to initiate the compression cycle can be high. This issue has been addressed in some air forks/shocks
  3. Generally harder to maintain than coil
  4. Generally more expensive than coil

Coil

Pros:

  1. Linear spring rate
  2. Generally smoother feel even on the biggest hits
  3. Generally cheaper
  4. Generally easier to maintain than air

Cons:

  1. Harder to adjust - the very cheap versions have no adjustment at all
  2. Generally heavier than air

Summarized from:
http://www.bikeroar.com/tips/coil-vs-air-mountain-bike-forks
https://enduro-mtb.com/en/best-mountain-bike-suspension-fork-2021-review/

4
  • 2
    +1 - The "Harder to adjust" pro/con needs to be emphasized and maybe expanded - with cheap coil forks, alternate springs are typically no available so they cannot be adjusted. If springs are available adjustment means buying new springs so costs. For a street bike/forks for comfort probably not a big deal. For an off road bike and moderately competent rider, it should be a deal breaker not having a selection of springs to choose from.
    – mattnz
    Dec 29, 2020 at 19:33
  • 2
    I think your first con is a little off. A progressive spring rate is better on a big hits as the bottom outs are not as harsh. Linearity is better for smaller hits.
    – Paul H
    Dec 30, 2020 at 0:38
  • 4
    I realize you pulled that point from the Bike Roar website. To back up my claim, which comes from experience, you can read here: enduro-mtb.com/en/setup-guide-mtb-suspension . To be clear linear vs progressive spring rates are not pros or cons, but preferences.
    – Paul H
    Dec 30, 2020 at 0:44
  • Thank you, coil sounds a better choice for me because less maintenance and the weight is not that much an issue because of I'm riding ebike.
    – MT247
    Dec 30, 2020 at 18:58
6

I don't believe you have much success in selecting a suspension fork. Looking at the bike, a suspension fork with exactly same geometry as yours would have approximately zero suspension. There is simply no room for a suspension fork with unchanged geometry. If you change to a suspension fork, it will change the geometry of your bike which will affect the steering characteristics. For example, the seat tube angle is changed (so you may run out of fore/aft adjustment in your seat post), the head tube angle is changed (so the fork trail affecting the steering characteristics will probably not be what the fork manufacturer intended), the bottom bracket height will change (so you will find it harder to mount and dismount due to increased bottom bracket height).

Every frame will have different requirements for a fork. If you see a fork, you need to carefully look at its dimensions and analyze what the fork trail will be and how the bottom bracket height and seat tube angle will change. Only with such an analysis can you determine if the new geometry of the frame/fork combination is acceptable.

A bike frame designed for suspension would have reduced head tube height from the lower end, making room for suspension below the head tube. For such a frame, the intended fork length is longer.

4
  • I agree with you. It's going to be a pain in the neck to do the work and will change the bike in unexpected and probably negative ways.
    – David D
    Dec 29, 2020 at 18:29
  • 1
    100% agree - that's why OP should keep any parts that come off the bike during the refit, in order to ease a later revert.
    – Criggie
    Dec 29, 2020 at 19:43
  • 2
    OP could switch to a 26er up front. At that price point OP would be looking at used parts, but you can get some nice second-hand 26" stuff since its popularity has dropped. Definitely a frankenbike, though.
    – Michael
    Dec 29, 2020 at 22:28
  • Hmm so you mean smaller wheel at the front like 26'' or 27.5''. Could be good idea.
    – MT247
    Dec 30, 2020 at 18:44
3

Juhist's answer correctly describes the trouble you're signing up for in your endeavour. Remixing your bicycle's whole geometry is not undertaken lightly.

One thing you may not have considered is a suspension stem. Redshift makes one that is on sale just inside your price point. There are others forthcoming, and a big list of styles and discourse at CyclingAbout, including some downsides:

Why should you avoid suspension stems?

The biggest issue is that any downward force to the handlebars will result in energy loss. This is not great for people who like standing up on the pedals, but shouldn’t be much of a problem for people who spend most of their day in the saddle. An issue that the 90s suspension stems suffered was movement under heavy braking. I presume that this effect is lessened on the latest generation of products given how much less suspension travel there is.

I don't think energy loss is much of a concern for an ebiker. You can just throttle up rather than stand on the pedals.


Please note that I have not used a suspension stem myself. If I were in your place, I'd put 5-20€ toward a pair of cycling gloves before I spent 100€ rearranging the front of my bike.

1
  • 2
    I think front suspension is must for ebike. I need to ride really hard puncture protection studded tyres(schwalbe marathon winter plus 50-622) because sharp gravel used to sand roads. Also I'm 85kg myself and the bike is 23kg and when going +30km/h speeds every pothole etc. hits really hard.
    – MT247
    Dec 30, 2020 at 18:50

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.