I'm hopefully back / Replacing forks?

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EasyCrank

Über Member
Location
Bristol, UK
Me/My Return
Hi all, I used to be a regular on this forum around 10 years ago and remember it was always a fantastic community.
My bike I'd inherited was already 30 years old when I took it on, and whilst I loved it, it was eventually time to be retired.

Then in early 2021 I bought a brand new bike and was super excited about being back on the road, then around a month later, I had an accident where I fell 230 feet down an alpine mountain (not cycling related, I'm a wildlife camera opp and was there for work), and in doing so broke my neck in 3 places, my spine in 3 places, my pelvis in 4 places, shattered my ankle, broke my knee, several ribs, my sternum, and my skull.

However, almost 2 years later and I'm now recovered enough that I'd like to get back on the bike. However, living on a hill and in the slope swaddled landscape of Bristol, at this stage in my recovery getting home may still be a bit of a challenge.

As a result, I decided to invest in a Swytch electric bike kit to give me some assistance until I could go fully manual again. I orderd it mid last year in preparation for when I'd eventually be able to use it. Yesterday I finally took the plunge and moved to fit it, but have found that the motor wheel that you need to replace your front wheel with is not compatible with 'thru-axle' forks, and will only work with u-shape ones. When I ordered it originally I don't think this was flagged and the main criteria was making sure your wheel size was right, and the forks were wide enough. They have since added the issue to their terms, so I may be able to flag them on it, but that doesn't really help me. Even if I could return it and get my money back, that's not what I want as I want to be able to use my bike, and this is still the best way forwards.

So, with all that said, I'm presuming my only choice at this point is to replace the forks on my bike (which after not having been able to work for almost 2 years is not ideal, but necessary).

My Bike Problem:
I need to replace the forks on my bike, but I've never replaced key components on a bike before (other than brake pads/disks, tires, pedals, and grips), and so have no knowledge of the area.

The bike I have is the TREK FX 1 Disk (2021) in medium, and I basically need some forks that fit this bike, will accommodate the brake mechanism currently fitted to mine, but that has a 10mm u-shaped fitting so a wheel can just slot straight down into it.

Would anyone be able to suggest one which is reliable (it doesn't need to be amazing, just good enough that it's strong and safe, and ideally doesn't weigh 10000kg), and ideally pretty cheap?
Also if there's any good online tutorials you could suggest on how to swap forks over that would be great.

Thanks everyone!

Here's a photo Swytch gives for the type of forks it requires, and it says it requires a 10mm dropout slot width:
Screenshot 2023-05-19 152402.png


For reference, here's a photo of my bike (you can view the full specs here):
PXL_20230518_143041676.jpg
 

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Ming the Merciless

There is no mercy
Location
Inside my skull
The headset is

IMG_5178.jpeg


Which means standard headset bearings / tube for a road bike. You can get tapered steerers now where the lower part of the fork inside headtube is wider, as are the bearings

The one thing I can’t see is the rake of the fork

https://www.ebcyclinglaw.com/bicycle-frame-geometry-fork-rake-and-trail/

Your fork is flat mount, so unless you want to replace the disc brake caliper you want a flat mount fork.

What you are after is a 1 1/8” fork, with same or similar rake (changes it affects how the bike handles), 405mm axle to crown, and flat mount, and QR. Flat mount might be the stumbling block as that came in similar time to thru axles. Plus clearance for 38mm tyres at least.

Is the Swytch disc brake, I presume it is?
 
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EasyCrank

EasyCrank

Über Member
Location
Bristol, UK
The headset is

View attachment 690309

Which means standard headset bearings / tube for a road bike. You can get tapered steerers now where the lower part of the fork inside headtube is wider, as are the bearings

The one thing I can’t see is the rake of the fork

https://www.ebcyclinglaw.com/bicycle-frame-geometry-fork-rake-and-trail/

Your fork is flat mount, so unless you want to replace the disc brake caliper you want a flat mount fork.

What you are after is a 1 1/8” fork, with same or similar rake (changes it affects how the bike handles), 405mm axle to crown, and flat mount, and QR. Flat mount might be the stumbling block as that came in similar time to thru axles. Plus clearance for 38mm tyres at least.

Is the Swytch disc brake, I presume it is?

The Swytch upgrade doesn't interact with the brakes at all (though it has a sensor just to read if you're applying the brakes).
The upgrade is basically they send you a wheel with a motor fitted. You replace your front wheel with that and then just strap the rest of the electronics to the frame and handlebars.

I'd already moved my inner tube and brake disk over from my old wheel to the new one before I discovered this was the case.
 

Ming the Merciless

There is no mercy
Location
Inside my skull
The Swytch upgrade doesn't interact with the brakes at all (though it has a sensor just to read if you're applying the brakes).
The upgrade is basically they send you a wheel with a motor fitted. You replace your front wheel with that and then just strap the rest of the electronics to the frame and handlebars.

I'd already moved my inner tube and brake disk over from my old wheel to the new one before I discovered this was the case.

So how do you brake if the swytch wheel doesn’t interact with them?
 
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EasyCrank

EasyCrank

Über Member
Location
Bristol, UK
So how do you brake if the swytch wheel doesn’t interact with them?

It's exactly the same as it always is. The Swytch provides assist power whilst peddling but stops if you stop peddling.
As I mentioned, it has a sensor that reads if you engage your brake and then cuts power to the motor if you apply your break. But it doesn't interact with them.
 

Ming the Merciless

There is no mercy
Location
Inside my skull
It's exactly the same as it always is. The Swytch provides assist power whilst peddling but stops if you stop peddling.
As I mentioned, it has a sensor that reads if you engage your brake and then cuts power to the motor if you apply your break. But it doesn't interact with them.

My point was the wheel as in the whole unit, is disc is it not? I’m not referring to the specifics of the motor in the hub.
 
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EasyCrank

EasyCrank

Über Member
Location
Bristol, UK
My point was the wheel as in the whole unit, is disc is it not? I’m not referring to the specifics of the motor in the hub.

Ah I see, well it doesn't come with a disk fitted but it does have the fittings and so I've just moved my brake disk over.
Here's a couple of pics of the motor wheel with the disk break I fitted.
PXL_20230519_160437002 (1).jpg


PXL_20230519_160443193.jpg
 
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EasyCrank

EasyCrank

Über Member
Location
Bristol, UK
Is it possible to fit a through axle to the hub ?

Unfortunately not, It's all wired in to the motor mechanism. Would basically involve taking the whole wheel and motor apart, redesigning part of it and building some bespoke parts. I think replacing the fork is probably an easier solution.
 

sevenfourate

Devotee of OCD
Welcome back 👋

Good luck with your forks. But sorry: I just can’t get past your accident. Sounds absolutely horrific. So its wonderful to hear you’re keen and able to ‘ride again’.

Good luck and stay safe 👌
 
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EasyCrank

EasyCrank

Über Member
Location
Bristol, UK
Welcome back 👋

Good luck with your forks. But sorry: I just can’t get past your accident. Sounds absolutely horrific. So its wonderful to hear you’re keen and able to ‘ride again’.

Good luck and stay safe 👌

Thanks! I'm excited to get back out there. My wife is slightly less excited about me getting on a bike after all that, but I'm definitely not going to be doing anything risky, I'll be taking it easy. For now at least...

Really hoping I can get this sorted, it was such a gut punch where after 2 years of recovery, and 9 months of this kit being sat in a box in my dining room, I eventually feel ready to fit and use it, and the bloody thing doesn't fit. Haha.
 
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