My Yamaha eMTB is awesome for mountain biking, but I also want to be able to use it on the street conveniently, and for this, there are a few issues:
1. The tires are too wide to use parking spots where the tire slots into a holder.
2. There is no kick-stand to use open parking spots with no holder
3. There is no built-in horn
4. There are no built-in lights
All of the same issues apply to my Panasonic XM-D2, except the last one.
(My PoweredBike has none of these issues, since it had to pass the legal requirements for a moped due to the stronger motor and higher-than-allowed assist - so it's even got turn signals).
Sol, let's go through these one by one:
Tires too wide:
It is a pain when I go to somewhere I haven't been before, and need to spend a lot of time trying to find a suitable parking spot. Parking spots with racks that your wheel slides into (and locks) are popular in Japan, but will not properly fit 2.75 inch tires. Even the XM-1 barely fits.
Interestingly, when I asked Panasonic at a trade show about a 29" version of the XM-D2, they mentioned to me "Well actually, the bike can accept 29 inch tires perfectly if you use thiner tires" - the Yamaha is also a 27.5 inch wheel with 2.75 inch tires, so I would have the same option.
If I did use skinnier tires, then I could be able to use the bicycle parking spots with racks much more easily, but I am not about to go buy a new wheel and tire at the moment, so we will let this one go.
No Kick Stand:
It's both funny and sad that both road bikes and mountain bikes eschew kick stands. At least with mountain bikes it makes a bit of sense.
With road bikes, I have no idea what they are thinking. Sure, a kick-stand may add a (very small) bit of weight and aerodynamic drag which could make the difference between 1st and second place in the hyper competitive world of racing where 0.1 seconds might matter - but it hardly matters for a commuter. I suppose the lesson is - you aren't allowed to use nice bikes for commuting?
With mountain bikes, it makes a bit more sense, since a kick stand could come out during large jumps, etc., and be a danger. Still, not everyone exclusively uses their bike exclusively for extreme things all the time. This isn't a realistic issue for normal trail riding, let alone street riding. People tend to counter with "But this bike isn't built for street riding!" - perhaps not, but it is perfect for it (Having a suspension is nice - that's why motorcycles have them...) - and not everyone can afford to have a mountain bike and a separate street bike. Just like skiing, I can only manage to do "real" mountain biking a few times a year - but the street is always there. Also, I have done mountain biking with my XM-1 which does have the kick-stand, and have had zero problems.
In fact, I think the XM-1 took the correct approach - they included the spot for mounting the kickstand, and allow the buyer to order the kickstand - or not. This way, you can satisfy both the purists and the more practical people.
I have found two solutions to this problem:
1. The Luna Cycle Peg Leg (and similar) - sadly, it seems this is no longer available for order.
This solution has a special washer with a part that extends out. You install this washer between the bike and the rear axle bolt, then there is a separate "leg" that you can attach to it. This means it is not a "kick stand", but it is a stand. You just have to bring the leg with you. You can see how it works here.
The problem is that the special washer tends to break. This is a small part that should be cheap to manufacture, so it shouldn't be an issue - but they don't sell the washer separately.
Sadly, the peg leg is no longer in stock, and has not been for a long time.
Upstand sells a similar product, though made from carbon fiber. It might not be able to handle the 25kg weight of an eMTB, but they also sell the "mounting tabs" separately - if only they would actually sell them. I have placed orders on their site multiple times, but they have never shipped anything. Mails to them have mostly gone unanswered. Their web site seems to be a placeholder at the moment, and Amazon USA shows their products as out of stock.
There are various clones on Alibaba, etc. - but most of them only have the mounting tabs for QuickRelease, not ThruAxel. What's more, most don't sell the tabs separately, so you need to buy another kickstand as well.
In case you are wondering, I think the reason why the tabs break is that you have to bend them to accomodate for the differences in angle depending on where you park. If there is perfectly flat land, then you adjust it to that once and you're done, but when the place where you are parking is slanted, then you need to adjust the stand in or out to adjust the andle and therefore the height. (This is because the stand itself can't be adjusted in length). Bending a piece of metal back and worth will of course degrade it, but they break surprisingle easily. This could easily be remedied with an adjustable stand and/or easiy supply of replacement tabs. (or a tab with some kind of hinge?)
Another way is to use the Topeak FlashStand Fat - this is one that you slide your pedal into and it acts similar to a tripot (Duopod?) to hold your bike up. The problem is that even though this is designed for burley mountain bikes, parts of it are made from plastic, and if you put the bike too far off balance, it can apply enough stress to break it (as I know from owning one broken unit...) I am not sure why they don't release an all metal unit.
Still, this can be mitigated by being careful and adjusting the stand appropriate when the ground is not perfectly level. (If the bike is mostly straight, then there will be very little stress on the stand, it's when the ground is slanted that the bike might be tilted more, and therefore put mroe weight on the stand).
This solution is not ideal, but it works fairly well.
Lack of horn/lights:
Sure, you can attach battery powered lights and a horn to it, but then you are stuck charging two more devices. I already need to charge my cycle computer, rear light/radar, and action camera. The bike has a huge battery, so it makes sense to hard wire whatever I can into the system. This means less things to carry around, and less things to charge.
Horn:
I originally purchased and used this horn from Juiced Bikes. It has a built in alarm, and a uilt in battery. The horn is a standard motorcycle horn, but they have included a button to mount on your handlebar, mounting hardware to attach the horn to your bike, and an internal battery and the electronics to make it work.
There are multiple good things about this horn:
a. It is sturdy metal, not chinsy plastic like most I have seen.
b. It is actually loud, and since it uses a real motorcycle/moped horn part, it sounds like a "real horn" - i.e. a sound that road users already know.
c. The latest version uses USB charging and comes with a metal mounting kit.
This is good because it is loud and you can leave it on your bike, but... there are some bad things too:
a. It is not 100% weather proof. I would recommend covering it up during heavy rain storms. The horn on mine started rusting, and if you store your bike vertically you will have bigger issues since it will act like a cup and collect water.
b. The alarm has no "pre alarm" warning beeps, meaning the first time someoen bumps it, it will cry bloody murder - which means youc an't realistically leave the alarm on if you are parking in a place where other people park. When someone takes the bike next to yours out of the rack, your bike will inevitably be vibrated a little bit, and nobody will be happy with the alarm going off every 3 seconds.
c. There is no external power version, so even if you use it on an eBike, you still need to charge it occasionally. Since it is meant to be left on the bike, this means an awkward dance of connecting a mobile battery to it in order to charge it. I haven't checked whether it can be used while charging, so perhaps one could hack it to just always be connected to USB (though waterproofing of the port would be needed).
After much searching, I ended up buying the B&M eBike horn from Bike24.
This horn is much smaller than the horn from Juiced Bikes, partly because it does not have an internal battery, and partly because it doesn't use a moped style horn. (I guess that they have a Peizo element inside).
I bought one of these, and liked it enough that I decided to buy a second one (one for the XM-D2 and one for the Yamaha YPJ MT-Pro).
The sound is quite loud, but they have been a bit flaky in operation, sometimes not working untile pressing several times. I thought this might be due to the voltage. (The unit is rated to work from 5 - 36 volts).
On the Panasonic, I stole power from the front light, which seems to work without issue, but requires that I have the light turned on for the horn to work.
On the Yamaha, since I split the power from the battery to provide power for the lights, I wired the horn into the same circuit.
Again the horn on both bikes has been flaky, and I supposed that might be due to operating them at the minimum voltage. (Like perhaps there is an internal capacitor that gets charged up when pressing the button the first few times).
Another "con" would be that although the sound is quite loud, it is of a tone that is unusual in Japan (Except it soudns similar to the horn in a police car?)
You can hear the sound it makes in
this video at 6:00.
Lights:
I was able to order the repair manual for the Yamaha, and determine where I could steal power from. I managed to order and connect a light from Supernova, as detailed in this blog post.
This light has been absolutely bullet proof. It is quit expensive for how bright it is, but it can accept a wide range of voltages, is made from very sturdy aluminum, and comes with a nice mount. Even the cable is amazing, but super rubbery and almost imposssible to strip!
The weather-proofing is impeccible, and I have no doubt that it will survive any kind of rain or snow. The color has not faded at all even after being outside for around a year now (unlike my Knog PWR lights, which have slowly turned from black to gold!)
(The generic light switch I ordered off of Amazon is also better than I expected - so far at least).
Cable Management and Horn issues
After the above mentioned blog post, I received the smaller eBike specific DC to DC adaptor for the light, and also tidied up the wired a bit. I had been planning to use smaller waterproof connectors (The cheap ones I had been using were absolutely huge), but crimping them was enough of a pain that I decided to just hard-wire most everything together, while eliminating excess cable.
Working on the cables while attached to the bike was challenging, but I finally managed to finish everything, such that the horn was no longer wired after the light switch, but before it - so that the horn could be used even if the lights were turned off.
After double-checking for shorts, I re-attached the battery, and tested the lights and horn. Everything seemed to work okay, though the horn was still a bit flaky.
When I went out for a ride the next day, though the horn didn't work at all. We have had a series of typhoons here over the past several weeks, so I assumed that water had managed to get inside the horn, damaging it.
I also thought that voltage might still be the issue. The horn is rated for 5 - 36 volts, but the bike battery can get above 36 volts (I measured 39 at full charge). In order to avoid damaging the horn, I had attached it for the DC to DC converter for the light, which outputs 5 volts. That may mean it doesn't really have quite enough voltage (particularly if the current draw from the light lowers the voltage) - so I decided to try to add another DC to DC converter just for the light, thiss time at 12 volts. Sadly, this didn't help matters.
One night after riding outside for a few hours (where the horn did not work at all), I came home, parked my bike, and went inside. After a about half an hour, the horn started making strange sounds (like half honking) on its own.
As I mentioned before, it's quite loud - so I ran outside in a panic to stop it before the neighbors complained. (This was bad because it was after 10pm and people might be sleeping).
"I see how it is, it doesn't honk when I press the button - but somehow it can honk without me pressing the button? Fantastic!", I thought to myself.
I took out the battery, and cut the wire leading to the DC to DC converter for the horn.
Warranty service for the horn would be difficult and time consuming, given that it was shipped from overseas. What's more, Bike24 doesn't seem to have any more in stock, nor does anywhere else I can find.
So, the next day I decided to try to disect the horn. It is basically a tightly sealed device, with no way to open it, short of cutting it open. There is a seam that I might be able to pry open, but there is absolutely go give at all, so I have a feeling that it may be somehow welded shut.
What I could play with, is the switch. The switch is not really entirely weather proof. The handlebar mount contains a U shaped piece of rubber, with the button on the top, and the rubber curving around to form the bottom of the switch. It is possible to open this sandwich and see that there is a small circuit board inside with a small metal dome. It's basically like the kind of button used in a calculator. The inside looked less than pretty, so I have a feeling that water had gotten into the delicate device and caused corrosion. The good thing is that when I powered it up and tried shorting the leads of the switch with a small jumper cable, it worked perfectly.
The cause of the reliability issue being the switch is honestly the best case scenario, because then I can just swap out the switch. I don't need to disassemble the horn or buy a new one, and may not need to deal with the DC to DC converter.
I have ordered a new switch and will test both with and without the DC to DC converter once it arrives.
I have considered hard-wiring a rear light into the bike as well, but that would look to be significantly more complicated.
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