Sunday, October 25, 2015

First Impressions: Yuba Spicy Curry Review

My Cetma cargo bike was recently damaged when a dump truck backed into it while the bike was parked. After reviewing a few replacement options for electric assisted cargo bikes (mostly the Yuba and the Larry vs. Harry Bullitt), we opted for the Yuba as it is easier to learn to ride and comes pre-equipped with a mid-drive assist instead of having to retrofit one. I will miss the box on the front, but I should still be able to carry all the crazy stuff I need to while having a bike that is easier to manage at low speeds and while walking.

With an aluminum frame and no giant wooden box, this bike is less than half the weight of my previous bike. It is light enough I don't use the assist nearly as much, saving it for hills. With the mid-drive system, the power is supplied through the cranks, instead of through the hubs. The cranks and the chainring can move separately, meaning the motor doesn't drive the pedals, only the chain (unlike a Stokemonkey mid-drive). This makes the motor engaging and disengaging a lot smoother.

Motor

The motor uses magnetic sensors on the rear wheel and cranks to detect motion, as well as a torque sensor on the cranks to determine when and how much to engage. The system is pretty seamless when up to speed, though there are situations when the motor kicks in when it shouldn't. When slowing to a stop and still pedaling, the motor will sometimes engage momentarily. Also, I have had it engage when walking next to the bike if the pedals start turning, as when going up a curb where the pedals get caught on the curb.



There are 4 levels of assist, with the lowest level being hardly noticeable and the highest level only appropriate for going up steep hills or going 20+mph on level ground. I usually leave it on 0 or 1 on level ground and 2 when going up regular hills. The motor helps most when pedaling slowly, around 50-60 rpms. The power drops as you pedal faster, with the assist not helping much when pedaling more than 80-90 rpms. For me, riding with the motor requires a slightly different riding style than without. The power of the motor drops as the battery gets drained. Level 1 on a full battery is the same as level 2 or 3 when the battery is at 40% charge.

The addition of the motor and the ability of the pedals and chain to move independently means the pedals are very far apart. About 5/8" wider (190mm total) than on a commuter or mountain bike (150-165mm). Personally, this is acceptable in exchange for having the motor in the cranks. The Cetma had the pedals about 1/4" wider than a mountain bike without a motor because of the wide chainstays.


I have noticed a little noise coming from the motor cover when pedaling. It isn't clear whether it is the two covers rubbing against each other or the cover rubbing on the frame. I will have to investigate as the creaking noise is annoying because the rest of the bike is so quiet.

Components
The components were very well chosen on this bike for good durability, value, and low maintenance. It uses Tektro hydraulic disc brakes with large rotors for fantastic stopping power. It is easy to slow the bike going downhill with one hand while signaling with the other hand. These brakes use mineral oil like Shimano instead of the DOT fluid used by other manufactures. Having bled other brakes before, I prefer to work with mineral oil, despite the higher cost.

The drivetrain is 8 speed with an 11-32 cassette, which I would consider changing to 11-34 when it comes time to replace it. Xtracycle and Bullitt mostly use 9 and 10 speed drivetrains, which seems unnecessary for cargo/commuter bike use. Replacing the chain and cassette when they wear out will cost 20% more for 9 speed and 100% more for 10 speed.

The wheels and tires are heavy duty, the rear wheel is 48 spokes and the front is 36, with both using extra thick 13 gauge spokes. Tires are Schwalbe Big Apple Plus front and rear, which is my personal favorite for cargo bike use. The wheels are a little easier to remove than on my previous bike, so I could probably use the regular Big Apple tires and change an extra flat now and again. The wheels come with a quick release. I would have expected axles with nuts on them for heavy duty use and for the extra security. I replaced the quick releases with security skewers. After I installed running boards in the back, I noticed that the quick release skewers wouldn't be able to open with the running boards on. This wouldn't be too much of an issue with the Yuba's running boards because they can be removed without tools. Mine are installed more permanently, so using the security skewers is good as the tool to loosen them just fits without removing the running boards.
Not much clearance between running boards and hub skewer.


Accessories
The bike comes equipped with front and rear lights as well as front and rear fenders. This is pretty unique, even among cargo bikes. The front fender was an inexpensive Planet Bike fender, which I replaced with the better supported (two sets of stays instead of one) and longer Planet Bike Cascadia fender.

The lights are Spanninga lights for use with ebikes. The front is a Spanninga Corona Xe, it has 3 leds that put out 20 lux that provide good indirect light to avoid blinding oncoming traffic. The mirror reflector and the lens used to direct the beam make it a little too diffuse and irregular (dappled might be the right word). It doesn't provide the uniformly bright light pattern of the B&M lights I use on my other bikes and (which vary from 50-90 lux). But the ability to mount the light in front of the basket instead of the handlebars means better lighting angle and stuff in the basket doesn't block the light.


The rear light is a Spanninga Lineo. It has a large central reflector with leds along the lower edge.

The lights are controlled via the buttons on the handlebar. The only indication that the lights are on is the presence of the backlight on the display, which is hard to see in sunlight. It would be nice to have a more distinctive indication the lights are on or have the lights come on automatically when the battery is on. I like to have the lights on all the time, even during the day. It is perhaps the easiest thing you can do to prevent collisions due to driver inattention, especially the left hook. There is a ambient light sensor on the display which will turn the headlight on automatically at night. I found it nearly worthless as it will turn the headlight off if you are directly under a streetlamp. I'm not sure if it just poorly calibrated or the fact that the sensor faces up is the problem. In any case, I just covered the sensor with tape and now the headlight comes on automatically every time, just like I wanted.

I opted for the double leg kickstand since Oscar will be climbing up from both sides and doing who knows what else on the bike once he gets comfortable. The wide kickstand and the low deck, mean the bike is very stable. I haven't gone through the trouble of trying to tip it, but it should be noticeably more stable than the Yuba El Mundo which starts to get tippy if more than one kid tries to climb up the same side of the rear deck.

Frame
The frame is aluminum with lots of points for mounting accessories. Many of the small mounting points are rivnuts, which are just held in place by pressure. This is ok for non weight bearing points. In places where there will be weight bearing accessories (front Bread Basket and the rear deck), they use solid aluminum rods that are threaded or unthreaded as needed. 

Some rivnuts visible above the running board, not sure what you would use them for.

Front Bread Basket mounts nicely to hollow tube running all the way through the frame.
Headset is heavy duty 1.5" instead of normal 1.125"

The entire frame is very well braced and stiff. The balloon tires at moderate pressure (35 psi) make the ride pretty smooth.

The bike is a lot of fun to ride for both driver and passengers. All the parts are relatively easy to use and should give a lot of worry free use. I can't wait to take on some longer rides, maybe another camping trip up the canal, or a day trip to Silver Spring. I'm looking forward to taking it to the Mid-Atlantic Cargo Bike Championships at Hains Point next weekend.

3 comments:

Leslie Bloom, LEED AP said...

What did you use for those running boards?
It looks like you made them yourself and I'm looking for any tips you might have, as I want to try the same!
Thanks.

Leslie Bloom, LEED AP said...

What did you use for those running boards?
It looks like you made them yourself and I'm looking for any tips you might have, as I want to try the same!
Thanks.

jefe said...

I used 1"x6" pine boards. I used electrical conduit going through the frame as supports. The fit was a little loose, so I wrapped the conduit in inner tubes until it was a good fit. I still haven't found a good way to attach the running boards. I tried conduit clamps and rubber coated clamps, both allow the board to slide around when supporting enough weight. I should drill strait through the conduit and run a long bolt through the board and conduit.