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
 
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.
 
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.
 
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How did you go with this goldconch? I'm looking to replace my 20" forks with something with some adjustment, they are horrible..
 
If you wanted 100mm dropouts and you bike is 1-1/8 threadless.

Air shocks

Spring/Oil shocks
 
Did anyone find a suitable set of air forks for their 100mm front wheels? I have a mate City and while I've replaced the rear shock, the front one desperately needs upgrading as it's terrible.
I had narrowed it down to the suntour xcm 20 and the risse rst spex 20, but both are kids forks that I worry will struggle with adult weights on a heavy e bike.
I'm hoping to hear a success story to fill me with more confidence
 
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