It’s now been 6 months on my Sur-Ron Light-Bee eMotocross bike. Stock from Lunacycle the bike easily gets over 40mph and it rides about like you think a 75cc dirt bike should. If you get rid of the limiter and put it in sport mode even an amateur like myself can easily wheelie the featherweight 119lb motorcycle. The problem is that in low speeds while trying to ride twisty singletrack the bike just doesn’t produce enough torque to be that much fun. The bike doesn’t have any kind of transmission and it’s geared from the factory to be very high in order to get that 40+mph top speed. This means that you miss out on the insane wheelie popping torque that I’ve gotten used to with a geared down 2500W BBSHD Ludicrous controller. This has all changed with the release of the Lunacycle 60 Tooth rear sprocket available here for $65 in either aluminum or stainless steel. I bought one of these a couple months ago and threw it on my Sur-Ron and it completely changed the ride experience and increased my love for this dirt cheap emoto.
The 60T Luna sprocket is available in Aluminum (for lightest weight) or Stainless Steel (for durability). Since I plan on upgrading the controller to a SINE wave ASI controller as soon as it is made available I opted for the Stainless version. I’m not a fan of Aluminum anything when it comes to the drivetrain, even though the 7075 alloy they use is supposed to be almost as strong as steel and a whole lot lighter. Incidentally the stock Sur-Ron 48T sprocket is made of stainless steel. Lunacycle includes the 8 extra links of 420 sized chain and a master link which makes installation a real snap, even if you have a hard time finding the right end of the screwdriver, like I do. Stick it in your eye, if it hurts that’s the right end to poke at the bike with.
I was able to swap out the old sprocket and get the new one on in about 30 minutes. Be careful that the chain does not come off the front gear when mussing around with the new sprocket (like it did for me) or you’ll have to take the whole thing apart again and put the chain on the front gear. The rear adjuster nuts are tricky to adjust with a wrench, I had to use some needle nosed vise grips. Removing the axle on the non-drive side after loosening the chain will allow you to easily take the whole wheel off. Take note of the chain tension before you start to take the wheel off so when you put the new chain on you can match the chain tension. Also use the adjusters on either side to line the wheel up straight and be aware that when you tighten the adjuster on the non-drive side the chain will tighten slightly, but no where near as much as when you tighten the adjuster on the drive side.
I’m sad to confess when I first ordered my Sur-Ron 6 months ago I had a little buyers remorse. Now that I’ve had 6 months to play with it, I can’t say enough good things about it. The bike has had no issues except that the front brake cut off came loose when my wife dumped the bike. Want the secret to a happy marriage? Don’t hand your wife a 6000W eMoto with a 60T sprocket and say “Here, try this” (or if you do remember to set it in ECO mode first).
One of my favorite parts of the Sur-Ron is that it feels totally safe going 30mph across a field with no roads on it. This effectively shrinks the size of my farm so that I can get anywhere on my 45 acres in less than a minute. For over 10 years I owned a tandem seated 125cc Twister Go-Cart with a gas motor which I used all of twice to get around the property and cost me more than the Sur-Ron ever did. It seemed like there was always something wrong with it, it wouldn’t start, the gas filter was clogged, the carburetor was gummed up or the exhaust was falling off. I spent way more time fixing that go cart than I ever spent riding it. Eventually I ended up selling it on Craigslist for a $2500 loss and I was happy to see it go. The Sur-Ron is always ready to go, and other than dumping a little lube on the chain I’ve done no maintenance on it in the 6 months I’ve had it. No air in the shocks, no air in the tires, all I’ve done is charge it twice a month. It always is ready to roll and the battery can do 13 miles on the road at full throttle and still have 50% capacity left in the pack (with the stock 48T chainring on it).
When tooling around the property with the 60T chainring and carrying tools on my crate I only use Eco mode because with the larger chainring it’s far too easy to have the bike try to get away from me in Sport mode. Wheelies with a string trimmer precariously hanging off the side is just not fun.
Although the Luna website claims that the top speed drops to 28mph with the larger chainring, that was not what I found. On level ground with 200 lbs of my fat-ass I was able to easily go 32mph (GPS verified). On slight downhill slopes I was able to go about 36mph, on a real downhill section you could probably push it close to 40 if the pack is fully charged. The thing you notice with the 60T sprocket is the increased acceleration from a standstill and a noticeable increase in hill climbing speed and power. Since both my wife’s 450 acres and my 45 acres are very hilly, this really makes the bike much more fun to tool around in.
Wanna know why I haven’t written any articles in the last 2 months? I’ve been grafting and planting over 1000 new fruit and nut trees. I’m not sure that would have been possible without the Sur-Ron, or at least I wouldn’t have been crazy enough to try it in the first place.
Although I’ve tried riding singletrack with the Sur-Ron, I don’t particularly enjoy it. The bike feels too heavy to me and not nimble like a 60lb electric fatbike. If you plan on singletracking with your Sur-Ron then the 60T chainring is a must have accessory, don’t even think about going with the stock chainring. If all you do is commute at high speeds and don’t care about wheelies then the stock chainring is fine.
Lunacycle has started a new website dedicated to electric motorcycles called electricmotorcycle.com . Right now it only features the Sur-Ron but it’s a site to keep an eye on as the future of transportation quickly becomes electric.
If you want the most insane acceleration off the line without upgrading the controller your best bet is to get the $419 supermoto upgrade which gives you much smaller wheel sets with slicks for street racing and pair it with the 60T chainring. You won’t be able to go much faster than 28mph on the level with the larger ring, but getting to 28mph will be a whole lot of fun. There is some exciting upgrades coming for the Sur-Ron, right now at Luna labs they are testing it with an ASA 8000 controller and getting 600 Amps peak without using active cooling (stock it’s less than 100 Amps peak). There is plenty of videos on Youtube of that bike outrunning 450cc racing bikes and even an Audi R8 off the line. From 0-25mph since the bike weighs only 120lbs and tons of power, it has a distinct advantage early on in any race. It even does respectably against the Zero DSR which is by far most fun electric motorcycle I’ve ever ridden.
The future for the Sur-Ron looks incredibly bright and I’m pretty stoked to be a part of it.