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I purchased the Swytch eBike conversion front wheel but I found that the axle was 11mm in diameter, which was too big for my hybrid bike and any other bike fork I've tried. Could you tell me if there are bikes which take an 11mm front axle or advice on what to do next. Thank you.

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  • Hi, welcome to the site. We don’t do product recommendations because they go out of date so quickly, so I’ve edited the question to try to make it on-topic. Feel free to edit again as you please and check out the site tour to read about asking great questions. If you can take a photo of your measurement, or of the axle not fitting the fork that could be useful to the question.
    – Swifty
    Commented Mar 25, 2019 at 6:09
  • "any other bike fork I've tried" - what year and brand, just curious? Mine fit Fuji bicycles with no modification other than wiping out any grease and gunk in the front fork's bottom.
    – NoBugs
    Commented Feb 25, 2021 at 4:20
  • Similarly disappointed. Received two 2021 kits yesterday and don't fit either of the bikes I bought them for - early noughties Thorn (26") and a 4 year old Raleigh (700cc). The 'instruction videos' are marketing rather than instruction and there is no sizing info on the website and nothing about this problem in the troubleshooting guide. I've had a go at filing the axle down on one, (still nowhere near yet) but I'm reluctant to take a file to forks for the fork washers though have people found this necessary?
    – Matt Bike
    Commented Feb 27, 2021 at 20:08

3 Answers 3

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Presumably you have a bike designed for quick-release wheels that have a 9mm diameter axle.

The Swytch eBike conversion wheel seems to use 10mm solid threaded axles that are secured to the fork with nuts - which makes sense as this provides higher clamping force required to handle the motor torque. (FWIW, this fact seems to be absent from the Swytch website, and it means that their product is not compatible with any bike.)

If your fork dropouts have sufficient material, you may be able to enlarge the dropout width with a file, but beware that you will not be able to use the 9mm axle wheel. It would be dangerous to do so.

You could also find a cheap fork designed for threaded axles. You would need to match your current fork's geometry (headtube to axle distance, rake). As threaded axle hubs are used on cheap bikes you will not find a replacement part available for sale as a separate component. You'll want to get one from a old used bike. A good source for things like this are bike cooperatives or bike stores that specialize in refurbishing old bikes. They often have piles of bikes that are not worth refurbishing or frames that have had parts stripped from them.

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  • Good thoughts - the risk here is if the motor-wheel doesn't have a torque arm, then the dropouts are the only hard surface transferring power, which could lead to the axle's flat sides chewing out the fork's metal. If the motor is 200W or less, then that's unlikely, 300W perhaps, and 400W+ it gets more probable.
    – Criggie
    Commented Mar 25, 2019 at 18:13
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    @Criggie I looked at the Swytch website, their front wheel uses torque washers with a tab that fits in the dropout slot, which means the dropout probably would have be deepened as well as widened. Commented Mar 25, 2019 at 18:33
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    This all makes the website’s claim of the kit fitting “99% of bicycles” seem a bit of a stretch...
    – Swifty
    Commented Mar 26, 2019 at 16:39
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    ^ I agree that could be more clear. Upon trying an old Mtn bike, it was too small, upon contacting Swytch they recommend filing the axle carefully!? but on two of the four bikes I tried to put on, the newer Fuji (2000s era bikes?) had no modification necessary and they are quick-release, fairly modern design. It's not fair to say "not compatible with any bike", just not compatible with everyone's bikes from 1990s.
    – NoBugs
    Commented Feb 25, 2021 at 4:18
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I wonder if there is any update to this, I have just installed a new Swytch Kit to my early 2000’s specialised Epic, I had to do a slight modification only during the first test ride this is what happened. I warn everyone to be careful as this could have been worse if I was travelling at speed:

Front Fork dropouts sheared off

No cracks in the drop outs beforehand, yes they were old and had been ridden well over the years but hard to tell whether that was the cause or not. No this was a standard kit with only half the power applied at the time the wheel and the fork parted ways. I had been testing the kit prior to this on the stand and this was on my first road test. Obviously I’m now very nervous.

Both sides went together (although I suspect once one side goes the other is going to break pretty quickly.) Looking for recommendations for which forks to replace with and be able to use the kit with confidence? I guess a steel or stronger lower leg material?

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  • Did both sides break together? Were there any pre-existing cracks in the dropouts before installing the new wheel? Given the bike was already 2 decades old, had it lived a hard life? This is certainly a bad place to be, if the front wheel parts compant with the bike while riding!
    – Criggie
    Commented Jan 22, 2023 at 0:15
  • Also - was it the plain kit or had you added more voltage/power at all?
    – Criggie
    Commented Jan 22, 2023 at 0:16
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I faced the same problem. Their website (used to) cheerily advise you to file down the axle...

I did it anyway, just using a hand file. Not the tidiest of jobs but got it on the forks. So far works really well. I'll try to remember to update this post if it ever goes wrong! (If you're reading this in 2022, feel free to nudge me for an update).

The problem with that though is then if you want to transfer the wheel to a new bike, you run the risk that it's then too narrow...

Screenshot of defunct help page instructing "If your fork slots are less than 10mm, thats (sic) not a problem. The best thing to do is bit by bit file down the flats on the Swytch motor axle"

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  • Hi, welcome to bicycles. Please only post answers that properly answer the question. If you're having the same problem, you can upvote this question or leave a comment on it. If you think you want a better or different answer you can re-ask the question or even post a small bounty on this one for a better answer.
    – DavidW
    Commented Sep 13, 2021 at 20:30
  • Is it still working for you? Someone else reports breaking their fork. Commented Mar 19 at 15:35

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