Fork issues, motor recommendations, and other newbie questions/issues

[99t4]

Last 3 photos show the RH side dropout is bent. Unless I'm seeing a photographically-induced illusory artifact.

You will want to repair that. If you don't know how or don't have the tools your FLBS should be able to do it for you in minutes.

Do you have any idea how this could have happened?

A photographically-induced illusory artifact? Poor lens choice for subject composition. For example, using a wide-angle lens to take a close selfie will make your nose look huge in relation to the rest of your face. That's not what you really look like, it's a distorted illusion. Not to criticize YOU, but rather your photographic skills (it IS difficult to get good detail shots with cellphones and point'n'shoot cameras) -- none of your photos so far have really been useful to show what your are trying to describe. Keep trying (it's cheap, compared to film) and delete the shots that are too busy/off-angle/don't show enough details. Post the ones that definitively show the problem. Make it easy for the experts here to say "A-HA, that's the problem," or "Nope, that's not the problem." Look at how much time you've wasted, going round and round on this fork dropout issue, for example. Goatman had a good suggestion-- take a perpendicular shot of the fork dropout by itself, and also with the axle installed w/o washers or other fasteners. My suggestion: pretend you are doing a photo shoot-- good lighting, no distracting shadows, dull plain background. Avoid throwing up a bunch of photos that do not clearly definitively illustrate the subject. Watch how soon you get your answer.

 

[Kemosabe70]

Last 3 photos show the RH side dropout is bent. Unless I'm seeing a photographically-induced illusory artifact.

You will want to repair that. If you don't know how or don't have the tools your FLBS should be able to do it for you in minutes.

Do you have any idea how this could have happened?

A photographically-induced illusory artifact? Poor lens choice for subject composition. For example, using a wide-angle lens to take a close selfie will make your nose look huge in relation to the rest of your face. That's not what you really look like, it's a distorted illusion. Not to criticize YOU, but rather your photographic skills (it IS difficult to get good detail shots with cellphones and point'n'shoot cameras) -- none of your photos so far have really been useful to show what your are trying to describe. Keep trying (it's cheap, compared to film) and delete the shots that are too busy/off-angle/don't show enough details. Post the ones that definitively show the problem. Make it easy for the experts here to say "A-HA, that's the problem," or "Nope, that's not the problem." Look at how much time you've wasted, going round and round on this fork dropout issue, for example. Goatman had a good suggestion-- take a perpendicular shot of the fork dropout by itself, and also with the axle installed w/o washers or other fasteners. My suggestion: pretend you are doing a photo shoot-- good lighting, no distracting shadows, dull plain background. Avoid throwing up a bunch of photos that do not clearly definitively illustrate the subject. Watch how soon you get your answer.

Thanks for the advice...I’ll try harder next time.


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[Kemosabe70]

I’m really liking the 2021 Trek Marlin

Would I have trouble fitting a rear hub motor into a rear drop out like in the photo?
135x5mm

 

[amberwolf]

There's not much "meat" there, so you would probably want to make torque plates to bolt to the dropouts to actually do the holding of the axle.

I recommend you look thru the Torque Arm Picture Thread to see what kind of things you can do, and what was needed for some types of dropouts for various power/torque levels.
https://endless-sphere.com/forums/viewtopic.php?f=2&t=26444
There's other threads and posts like that with even more info, scattered around the forum.

 

[Kemosabe70]

I’d like to keep a brand new bike free of scratches from trial and error, Is there a default easiest drop out to work with?
Knowing that would make it a lot easier to find the bike.

My heads spinning thinking about all this to be honest.

Any chance I get during the day I search this forum for my questions, and then I come here and ask what I can’t figure out. I really just want to get out there and ride already, I just need help figuring out a bike to convert for now, when I get some time I’ll take better pictures of the damaged fork, but for now I just want something easy to look for in a rear drop out.

 

[amberwolf]

The best unmodified bicycle rear dropouts for a hubmotor will be very thick, and very deep. Preferably with most of the dropout slot between the stays, so the stays act to push against the dropout edges and hold them closed against the twisting forces of the axle (which your fork's dropouts couldn't do).

Dropouts that are like your front fork you have now, or like that in the pictured red bike, will not be deep enough to entirely contain the axle, which increases the likelihood of it prying them open.

The thinner the dropouts are, the less surface area of them there is to meet and secure the flats of teh motor axle, so the less able they are to resist the pressure of that axle trying to rotate, and the easier they are to deform.

The less deep they are, the less of a "lever" there is to resist the prying forces of the axle rotation.

 

[Kemosabe70]

The best unmodified bicycle rear dropouts for a hubmotor will be very thick, and very deep. Preferably with most of the dropout slot between the stays, so the stays act to push against the dropout edges and hold them closed against the twisting forces of the axle (which your fork's dropouts couldn't do).

Dropouts that are like your front fork you have now, or like that in the pictured red bike, will not be deep enough to entirely contain the axle, which increases the likelihood of it prying them open.

The thinner the dropouts are, the less surface area of them there is to meet and secure the flats of teh motor axle, so the less able they are to resist the pressure of that axle trying to rotate, and the easier they are to deform.

The less deep they are, the less of a "lever" there is to resist the prying forces of the axle rotation.

This is a dropout from a wabi special made from Reynolds 720 steel. Looks pretty easy to work with, what do you think?
The frames also lugged at the welds so I guess that would add some strength. It’s super light though dk if it the frame would hold up but the drop out looks thicc

 

[amberwolf]

This is a dropout from a wabi special made from Reynolds 720 steel. Looks pretty easy to work with, what do you think?
The frames also lugged at the welds so I guess that would add some strength. It’s super light though dk if it the frame would hold up but the drop out looks thicc

The only potential issue would be that there is no "frame support" of the bottom half lf the dropout, since the stay is connected to it's end rather than it's side, but that's common for single-speed frames.

So in theory there is less resistance to the prying action than otherwise...but it is still a much better choice than the red frame that barely has enough dropout for the bicycle axle.

The deeper the axle is in the dropout, the stronger it will resist axle rotation, so the further back the axle has to go to tension the chain, the less it will do that.


As long as the torque arms are correctly mounted, so that they prevent axle rotation, it still shouldn't be an issue. That torque arm thread (and others) have info on how to mount them best for this.



Just remember--NO bicycle dropouts are designed to resist the torque of an ebike motor axle. So while you can find some that happen to do this better than others--none of them will do it as well as a purpose-built device like a torque plate that bolts to the dropouts/frame.

 

[Kemosabe70]

Any suggestions on brands or specific frames that would be disc ready and easy to work with?

 

[Kemosabe70]

F**k it, I’m going to buy a disc ready fork for the street king and work out the kinks on it.

I still want to get a new rear hub for it. I have attached some photos of the rear end.

Any thoughts would be appreciated! And if my photos suck just let me know I’ll try EVEN harder :lol:

I’m too busy to take apart the rear wheel, but it does seem to be about 5.5 inches wide. So I guess 130mm-135mm?

I also want to use a rear rack I wonder if that would would be a hiccup when trying to attach both that and a torque plate.

 

[99t4]

That one would work. Not the absolute best but not a non-starter, especially with a good quality torque arm, something like Grin tech version 4, should be possible to get it positioned to also leave space for the rear rack support attacnment. Study this page:
https://www.ebikes.ca/product-info/torque-arms.html

Last photo; what happened to the axle nut? (rounded?)

Not sure what you are trying to show with the tape measure? :?

 

[amberwolf]

I’m too busy to take apart the rear wheel, but it does seem to be about 5.5 inches wide. So I guess 130mm-135mm?

Most likley the bike manufacturer's site has info on the frame specs, including dropout width.

I also want to use a rear rack I wonder if that would would be a hiccup when trying to attach both that and a torque plate.

Just put extra mounting holes in the torque plate. You could even make one that has disc brake mounts. I think there's at least one like that in the torque arm picture thread.

 

[Kemosabe70]

Last photo; what happened to the axle nut? (rounded?)

Not sure what you are trying to show with the tape measure? :?

Uhhhhh I didn’t have the proper tool to remove it originally, so yeah going to need to better nuts back there

I just wanted to show you guys it’s thickness.

 

[Kemosabe70]

The website doesn’t have the info for some reason, but I messaged them!

I was ready to pull the trigger on a Mac kit, I’m thinking I’d be best off with a 12t being that I’m going to put it on a 700c rim, it seems like the Mac is sold out like everywhere. I wouldn’t mind spending the extra dough on a GMAC if it’s worth it...any other motors I should be looking at?

 

[goatman]

have you looked at the luna wolf pup battery to see how they parallel connect to the luna wolf battery for more range? grin has a v2 torque arm that might fit to that rear hole of the drop out but you might get stuck using torque washers because of your chain tensioner, washers might be enough?

 

[Kemosabe70]

have you looked at the luna wolf pup battery to see how they parallel connect to the luna wolf battery for more range? grin has a v2 torque arm that might fit to that rear hole of the drop out but you might get stuck using torque washers because of your chain tensioner, washers might be enough?

Whoa wolf pup seems really cool. I have the v2 on the front right now, once I get a rear motor I will start experimenting.

I’ve got some double wall alloy rims that came stock with the street king, I’m wondering if it would be advisable to lace a new motor onto that?

Specs from Wyatt:

Wyatt Street King, Alloy, Double Wall, 35mm Deep, CNC Machined Sidewall


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[Kemosabe70]

Here’s a pic of what goatman is talking about.

I think I’m sold...

 

[goatman]

count the spokes on your rim, if you have 36 spokes and your motor is 36 spokes you can lace them together

 

[Kemosabe70]

Ebikeling said they’d replace my front motor with a rear motor. I am tempted to just do that, but I feel as though it’s a waste of money ($358) being that ultimately, I want a geared hub, a better controller and display. I really wanted a Mac motor, but I’m not seeing any in stock anywhere. I wouldn’t mind spending more than the original investment if you guys have any suggestions.

Decisions, decisions...I have this weekend to decide whether I exchange or return the kit.

 

[Kemosabe70]

New rack!

I play on installing the controller underneath it.

It looks cool, but unsure if it can hold any weight :lol:

 

[Kemosabe70]

*UPDATE*

I have purchased a new Soma fork (Soma Lugged CX Disc Fork, 700c 1-1/8" - Black)...it has disc brake mounts and I will be buying a new front wheel shortly to use disc brakes with, so that should fix the braking issue.

Going to either buy or make eyelet risers for the rear, so that I could use the rear mounting holes on the rack and push it forward a bit.

I’m too lazy right now to take apart the rear, but if it’s too small I may need to cold set it, which seems pretty straight forward?

Still have yet to decide what to do about the motor, ebikeling has been so kind to offer me an exchange for a rear motor, it’s either that or replace with a new kit.

 

[amberwolf]

If you're interested, here's a post with pics showing the issues I was describing with a hubmotor axle being a different diameter curve than the dropout, some damage it can cause, and a potential solution to it:
https://endless-sphere.com/forums/viewtopic.php?p=1565317#p1565317

 

[Kemosabe70]

If you're interested, here's a post with pics showing the issues I was describing with a hubmotor axle being a different diameter curve than the dropout, some damage it can cause, and a potential solution to it:
https://endless-sphere.com/forums/viewtopic.php?p=1565317#p1565317

Very cool! My buddy has a 3D printer maybe it’ll come in handy once my new motor comes in. I think I’ve settled on a Mac motor, I see they’re back in stock on em3ev, but I’m unsure which to get.

Check out my new thread asking for recommendations for which Mac motor and compatible accessories for this build.
[https://endless-sphere.com/forums/viewtopic.php?f=1&t=106900][/URL]

 

[amberwolf]

3d printing is not sufficient for an actual part to do what's described there. It's a great way to test for the fit, like that person did in that post, but it won't survive motor torque, etc.

 

[Kemosabe70]

I can order a Mac motor from em3ev tonight, I don’t know which winding to get to match my needs/ battery. They only offer a cycle analyst v2 (not sure if v3 is better and why and if it is I’d get it) and no regular display..do I need a display too? They’re also sold out of throttles so maybe I can just grab everything from grin? I am also unsure of which controller to get, be it an Infineon controller from em3ev (and then if so idk which I’d get 6fet, 9fet, 12fet) or something else from somewhere else? I plan on mounting the controller underneath my rear rack for a clean look.

Also, is the GMAC that much better?? It’s SO much more expensive.

So to sum it up:
Which winding for the Mac?
Which controller/display?
Do I even need a display If I get the CA?
Is the GMAC worth it over the Mac?