20" folding ebike front suspension retrofit options?

goldconch

Active Member
I'm hoping someone with more folding bike headset experience can help me: I'm shopping for a front shock suspension fork for my 20" folding Qualisports Dolphin with disc brakes. I'd prefer to swap-in a quality magnesium product rather than the cheaper cr-mo alibaba stuff (which would be heavier than my stock aluminum forks). Is there any manufacturer that makes a quality retrofit for ebikes with std BMX 20" x 2.40" tires? Is there anything out there for this bike?

Appreciate any help from those that may have done this before.

HEADSET:
Custom, Internal Cups, Straight 1-1/8"
STEM:
Custom Aluminum Alloy, Folding, Telescoping Height, 290mm Base Height, 170mm Extension, Quick Release Clamp, 25.4mm Clamp Diameter

Looking for something like this, but in correct size:

s-l1600.jpg


...rather than this (which seems to be the correct 10cm width for my wheel):

s-l1600-1.jpg
 

Timpo

Well-Known Member
That first one is 26 inch.

It's the same one as AliExpress fork, sold by several sellers.

I have one, mine is Bolany brand, I also bought Pasak and Hero Fork branded one as well.
The quality is impressive for the price.

As for magnesium.. yeah they do claim that, but I have never taken to a lab and checked.
 

Nova Haibike

Well-Known Member
I'd prefer to swap-in a quality magnesium product rather than the cheaper cr-mo alibaba stuff (which would be heavier than my stock aluminum forks). Is there any manufacturer that makes a quality retrofit for ebikes with std BMX 20" x 2.40" tires? Is there anything out there for this bike?


The Suntour XCM HLO AIR SL 20 will accommodate tires up to 2.3". Also available is the RST Spex; they do not indicate a maximum tire width.
 

goldconch

Active Member
Thanks @Timpo those look to be 4" fat tire/"snow bike" (per alibaba) forks, and won't match the 10x100mm fork dropout for this project, but I will bookmark.

If I can recover from the mildly offensive inference that I'm a kid bike rider, the Suntour XCM HLO Air SL 20 that @Nova Haibike suggested might fit, but list a 9x100mm fork dropout...The RST Spex 20 15/9, though interesting, are also not a perfect fit. Maybe I could grind out a 1mm if I needed it and add some washers on a longer hub axle...I'm fully expecting to have to mill off the top of the steerer pipe anyway, so the toolbox will be out. I don't want to trigger cascading expenses of having to buy a new front wheel and axle, milling etc.

The Suntour are 1780g (almost 4 lbs), and the lightest of four RST, the 9Air, are 1,800g, about the same.

It seems like we need more e-bike riders to drive the customizing component aftermarket.

Appreciate the helpful links - these will certainly help others too.

Update: Rep from Suntour says their youth-specific XCM NLO Air SL20 max tire width is 58mm and are not for adult use.
 
Last edited: