New bike with weird front dropout - Need to fit front hub

[Electricmover]

You're better taking a picture and uploading to this website. There are two kinds of forks. Threaded and threadless, and you had you hand covering the end of the other fork in the video, but I think it's threadless. And within each category, you have 1" and 1-1/8" diameter stems, making four kinds of forks.

A further distinction is suspension forks vs hard forks, AS a general rule suspension forks are a poor choic for motors if they are made of alloy, which is brittle. You can get away with suspension forks if you have a smaller motor plus good fasteners, which include torque arms. Changing forks takes experience and a bunch of parts, Going from threaded to threadless means you have to buy a new step to hp;d the handlebars.

I think it would be simpler to grind off the welds on the first forks, and use good fasteners.. Makes it easier to change a flat tire, Your motor doesn;t look too big either,




.

Yeah could probably grind them off with an angle grinder or something?
Yeah motor is quite small. This is not going to have a very high top speed. Will shoot in 500 watts approximately. At the most 600 watts in a slope perhaps. What type of fasteners would you go for? Something similar to torque washers?

 

[harryS]

These torque washers are amazon. Same price from China, might as well get these. I;ve used this torque arm from ebikeling on amazon.

Commercial ebikes don't usually use the long torque arms, but their forks and frames are better suited for motors, They're flat and wide where the motors go in. By the way, in this picture, nothing wrong with putting the torque washers inside the frame, if they fit, It's always about space, They're going to work on either side, but it affects the disl braje spacing here,

Forks often have those round insets around the axle to accomodate those lawyer lip washers. When you install a motor, you have to fit a washer in those recessed areas so everything is clamped tight.

 

[Electricmover]

These torque washers are amazon. Same price from China, might as well get these. I;ve used this torque arm from ebikeling on amazon.

Commercial ebikes don't usually use the long torque arms, but their forks and frames are better suited for motors, They're flat and wide where the motors go in. By the way, in this picture, nothing wrong with putting the torque washers inside the frame, if they fit, It's always about space, They're going to work on either side, but it affects the disl braje spacing here,

View attachment 186689

Forks often have those round insets around the axle to accomodate those lawyer lip washers. When you install a motor, you have to fit a washer in those recessed areas so everything is clamped tight.

Yeah thanks. Looking at one of my videos you can see that I have torque washers on the inside there.
But maybe I could also strengthen this whole thing with extra torque arms. Just not sure where to anchor them. Maybe on the inside there where the washers are as well?

The torque arms you linked looks similar to mine. As m Robertson said(I think it was?) that the straps they come with are rather weak. But I've seen guys drill their own holes through them, instead of using the metal strip/strap, to make them stick to the frame better. In that case I would drill a hole through the fork where the green circle is on this picture. And then put a bolt and nut through the fork where the green circle is. Then I think it would stick to the bike.

The fork should be able to handle me drilling a hole through it don't you think? Or would this ruin the structure of the fork a lot? I have drilled holes through frames before but that was to insert battery- and controller mounts on the top and downtubes so I am not sure if the fork's structure could handle this?

 

[harryS]

At least cut the bottom off the lawyer lips so you can slide a wheel in without spreading the fork. I figure it's a steel fork because he welded steel rings to it, So the spreading didn't ruin it,

 

[Electricmover]

At least cut the bottom off the lawyer lips so you can slide a wheel in without spreading the fork. I figure it's a steel fork because he welded steel rings to it, So the spreading didn't ruin it,

Both steel and aluminium should be able to handle a small drill hole don't you think? So I can fasten the torque arm really securely. I think I will do this. I don't think the wheel will come off if a strong structure like that is keeping it in place.

 

[m@Robertson]

if it is possible to switch these two? What do you think?

Maybe, so long as you do NOT try and put a motor on the front wheel. Look at the pics of the sheared dropouts that @harryS put up. Thats typical. And also on a suspension fork, they were never meant to be pulled on. Only pushed into. A motor pulls on the fork and you can actually watch them try and pull the thing apart, which they can eventually do... but I have always seen the dropouts break first. You see the forks pull apart and its really freaky, but the catastrophic failure you see time and again is the broken dropouts.

So you really did spread the fork to get the wheel on. Grind off those welded washers.

He can't do that. If you work at it you can freeze his first video at just the right spot to be able to see one of the underlying steel dropouts. And they have been spread. So there was a motor spinout and the owner welded on the washers to salvage the fork. They are the only reason it is functional at all, and you can't go back. That fork is a goner.

Here's the thickness difference between those lawyer lip washers and torque washers. If a motor can crack off cast aluminum dropouts, it's going to bend the soft steel on those lips.
View attachment 186680

Actually you have a mix there with only one lawyer lip washer. The leftmost washer is a cheap torque washer, and its a very poor (but common) version that fits way down low in the dropout. The middle one is the better torque washer that fits up higher and has a better chance of working on a light duty motor. The one on the far right is a lawyer-lip thingie. Its little tab is 90 degrees and sorta pin-sized so it can fit into the hole in the fork above the dropout. Fit into the pinhole, it forms a last line of defense and holds the wheel onto the fork, even if the bolt loosens but is still on the axle. The innermost washer would not work as a hanger and would be too big to fit into the little hole on the fork.

 

[m@Robertson]

This is what Lawyer lips actually are on a fork that has not been violated. That hung-up washer in conjunction with the lips forms the safety feature. But I think more often than not only the lips are in use. You seldom see the pinhole for the washer hanger thinger.

 

[m@Robertson]

If you cut the bottom off of those torque washers, things will go from bad to worse. For starters, the washers are oversized and do not match your motor axle width. Small motors tend to use an M12 axle with 10mm flats on both sides (a very few have no flats at all and are meant to be held fast with strong nut torque only).

So from one of those vids it looks like you have torque washers welded on that are meant for a larger-size motor, which is M14 with 12mm flats... or maybe its even worse and those washers are meant for an M16 which is the really big direct drive axle size. It was hard to tell from the video. Either way ANY gap is a failure-in-progress. Your motor if it held in that config only did so because of really strong nut torque on the oversized 'dropout' whose structural integrity was never great, and will disappear if you turn an 'o' into a 'c'.

Replace the solid (non-suspension) steel fork with another one. They're cheap even brand-new.