EVD 3000w w/Lithium Batteries
This got posted at the end of a XM-3500Li thread, thought it deserved a topic to itself.
This is Randall with R Martin Limited.
I wanted to post at this forum about our new EVD with 60ah LFP batteries. We just received them Tuesday and have finished our testing. The lithium EVD charges to 73 volts. It uses the Thundersky batteries and Thundersky charger. It has excellent acceleration and will reach 60 mph (tested with a GPS). Our speedometer is accurate.
Our VRLA EVD with the 50ah BB batteries will reach 50 mph (GPS Tested).
We have these in stock and ready you ship. The lithium models have limited availability (our dealers are taking several of these). Call or email us about shipping. We are offering free shipping to many areas.
Randall, I'm looking at your website, and it looks like a nice product. Appears to be based on the same gas scooter body as the XM3500, but you've done some things differently on the electric side. Can you give us a little more detail on the differences?
I notice that you are listing a 3000w motor, but it looks like you are getting better performance than the 3500w. Without divulging any trade secrets, can you tell us what you did?
I don't see a BMS listed, what are your plans in that direction?
What's the gross vehicle weight with Lithium batteries?
If you put the higher-torque motor of the EVD+ into the Lithium battery model, where would your top speed end up?
The correct address is : http://rmartinbikes.com
Randall - a few questions/comments;
1. Looking at this bike it has 21 cells so should hold a decent voltage provided it has a BMS - does it?
2. You mention a 30% slope - what speed and load? I assume this is with your higher torque motor...
3. It appears you offer two motor options for high torque or high speed; what speed does the higher torque LFP get and what slope can the higher speed LFP handle?
I also see the expected price for the LFP version is $5599 so a fair amount more than the $3990 I spent on the 3500. Otherwise it looks identical to the 3500 from the outside.
Thanks for your questions. I will answer these as best as I can. I am the sales manager so I will have to defer some of these to our techs.
I will also copy this to the new R Martin w lithium board....thanks MikeB.
1) We use 21 TS 60ah cells without a BMS. A BMS addition is a great upgrade to any DC system and we may offer it in the future.
We have previously tested 40ah lithium cells in series in ouer EVD. The 21 40ah cells in series would charge to slightly varying voltages depending on the temperature and how far they have been run down. Sometimes they would charge to slightly over 80v and other times they would only reach around 75v. The 40ah EVD always runs fine. We did not sell it because there isn't much performance difference over the VRLA model. We also use 21 cells because the performance is better. We expect the 60ah cells to show similar characteristics.
2) The 30% slope figure is from the manufacturer. Like all electrics, the EVD will slow on hills but we have never encountered a hill that the EVD will not make it up. We have had customers test on some really steep ones. Today, I was testing the lithium EVD and was able to accelerate while going up a slight hill at around 40 mph. This is pretty darn good for an electric in my experience.
3) We have two VRLA EVD+s with the higher torque motors in stock. The higher torque has a top speed of 40 mph. The higher torque helps at slower speeds on steep hills. It has not proved to be a big advantage. The regular VRLA EVD works fine on hills as described above. One advantage of the higher torque model is a longer range since the top speed is less. The higher torque is achieved with more windings in the motor.
Our lithium EVD uses 60ah instead of the 40ah cells. They are quite a bit more expensive. We also use 21 cells. We have a 6-phase motor and controller. Our disk brakes have been changed to a Taiwanese supplier with a better product.
This and the fact that we are a licensed distributor is reflected in the pricing. We are required by law to honor the manufacturer warranties. We also have a complete stock of EVDs and all spare parts in our warehouses.
Where we don't currently have dealers established, we will offer a significant discount - with the understanding that you will self maintain the product. We will provide warranty on the batteries, motor and controller. Please contact us at email@example.com if you want more information.
One more thing....the top speed of 60 mph was on a slight downhill. The bike will maintain 55-57 on flat ground.
Sounds like a good bike. The upgrade to 60Ah batteries (from 40Ah) is definitely a very good thing. Folks should note that as well as better range the batteries aren't being pushed as hard (in terms of their C/discharge rating).
A question for you: How does the acceleration of the VRLA high-torque bikes compare to the LFP high-speed bike? Torque not only gives better hill climbing - it gives better acceleration too. Of course we always want everything - perhaps we can't have great accel and good top speed? The XM has great accel (compared to the EFun-D 21 cell LFP bike I've ridden), but a lower top speed.
One more thing....the top speed of 60 mph was on a slight downhill. The bike will maintain 55-57 on flat ground.
If I were you I'd change your website copy to say 55mph is the top speed. No doubt about it - it's a better top speed than your main competitor right now (the XM). Also, 55mph is a reasonable top speed to achieve - after all it's the speed limit on a lot of out of town roads. I think the market is waiting for a breath of fresh air in seeing accurate and perhaps even conservative statements of top speed. I'm not speaking for X-Treme (I never do) - I'm just a dealer representative. But I am also someone who is living through the top speed debate. Your choice of course.
Good luck with the new bike - it looks good! And competition helps everyone who wants to see improvements.
Thanks for your questions and feeedback.
First off, we will be lowering the top speed number to 55mph on the web site. I went out and verified the speedometer today with a high-end Garmin GPS. I weigh 190lbs. I got up to 55 mph on relatively flat terrain.
The 60ah model accelerates much better than the VRLA or 40ah EVD. The 40ah EVD performs nearly the same as the VRLA model. Our VRLA batteries are 50ah so this seems to offset the weight and voltage difference of the 40ah model. The VRLA model is a better value in our opinion than the 40ah li. That is why we never marketed the 40ah. We do offer a discount on the VRLA models to folks that will self maintain. We protect our dealers so these discounts are not offered in areas where we have established dealers.
We are recruiting dealers so it would be great to have you as a EVD rep. We offer protected territories.
Hi MikeB - What is the ETA for your EVD? Let us know what you think of it. My wife and I are deciding between the EVD (lead acid for $3499) and the XM-3500 (lithium for $3999)... just a $500 difference for lithium! As for the performance specs, both scooters meet our in-town transportation requirements. Thanks for helping!
Alright folks, I've decided to give the EVD a try. I just placed my order, and they've got bikes in stock. I'll be reporting back with my experience for the benefit of the forum.
Hi all! This is my first post, but I have been a lurker for the past four months. I thought I'd chime in since I have been an RMartin EVD owner for close to a month now. I own the SLA version, not the new lithium model. I purchased the bike from an RMartin dealer in Longmont, CO called Small Planet Earth. I decided on the EVD after testing both the Zapino and this bike because of the better ergonomics (I'm pretty tall) and a higher top speed and range. I immediately installed a BattEQ on the bike after I first got it.
I have put close to 320 miles on the bike in the past few weeks, and have ridden it in a variety of conditions on roads ranging from a 25 to a 45 MPH speed limit. Since I live in Colorado Springs, CO, I routinely ride on hilly roads with grades of up to 15%. I have been using the bike to commute to work, which is a roughly 20 mile round trip on roads averaging 35MPH. I occasionally will also use the bike to run errands coming home, which will up the total commute to around 25 miles. The longest I have ridden the bike before recharging is approximately 32 miles (at around a 35MPH average speed), at which point I started experiencing low-voltage cutoff during hard acceleration even though the battery gauge still read around 1/4 full at a stop.
I have a road close to my house that has a third of a mile stretch of flat ground where I have tested top speed. I am 6'5" and weigh 220, and I have gotten the bike to a top speed of 52MPH which was verified with GPS. I have ridden the bike close to 60MPH on a slight downhill while commuting to work before having to brake, which leaves me to believe that it is capable of more.
My experience with the bike thus far has been mostly positive. I enjoy the flexibility that the ~30 mile range at traffic speeds gives me. The acceleration is fairly brisk and the handling is exceptional. The suspnsion is able to absorb most potholes and manhole covers without jarring me too much. The hill-climbing performance is decent, though I will decelerate to around 30MPH on the steepest hills. On lighter grades, I can accelerate going uphill to around 40MPH.
This being said, I have experienced several issues with the bike that I will probably seek to get fixed under warranty. The bike since new has had an extremely vocal (squeaky) front brake that will chirp for several seconds after releasing the brake lever. The front wheel also seems to be out of round, as the bike handlebars will vibrate heavily (to the point of wobbling so badly that not correcting will lead to crashing) if I don't keep both hands on them. The BattEQ that I installed has also had some interesting readings. For the first three weeks, three LEDS were lit (indicating three battery balance issues). One week ago, one of the LEDs went out and in the last two days, all LEDs went out after charging fully. The LEDs for batteries three and five will still immediately light upon riding the bike any distance, which may indicate battery issues. I'm not too concerned since the battery string is always within .10 volts from the highest battery to the lowest, but I am closely monitoring the batteries.
I can't think of any other pertinent info to share, so let me know if you have any questions.
I would definitely stay off the juice until you get the front end from wobbling. That's bad news in a brown bag.
I received a Lithium EVD from E Martin on Weds. But I have been very busy with work and been slow to get the scooter up and running.
The buying experience was excellent, Randall was very helpful and very knowledgable. They had good inventory of all color combinations. I chose the blue/white version, which is very nice. As there was no dealer in my area I received the discount for customer serviced, which made the price very reasonable. From first contact to delivery was 5 days. The scooter arrived undamaged and was very well packed and prepped with detailed dealer prep instruction. I had to mount the windscreen, trailing arm side cover, mirrors, and throttle handgrip assembly, along with checking all nuts, screws, etc for tightness. All this was effortless. I could not find anything wrong thru my inspection. Most importantly I found nothing that I would change other than adding balancing leads to the battery cells.
My first impression of the EVD is the quality is way up there. The instrument console has diagnosis lights, an accurate speedometer with MPH as the major unit, The fuel gauge is accurate. The quality of the body work is very nice, the seat is very comfortable and not hard. The suspension seems softer and handles bumpy roads very well. I could tell the disc brakes have been upgraded and they work well. It was hard to tell acceleration wise that I was carrying close to 50 more pounds of batteries for the 21 60AH cells.
I am 6'-3 and 210 pounds and had no problem doing 55mph on a slight incline. Acceleration was very responsive and will keep up with traffic no problem. The EVD does not have the two speed button for high and low speed, so starting off from a stand still takes some getting used to the EVD is a little touchy on the throttle due to its torque. A group of us(some short, some tall) at work gave the bike pretty good work out and everybody was very impressed.
The scooter also arrived with the MCO and Invoice for registration purposes. I am currently going thru the process of educating local insurance agents and dealing with the DMV on getting thru the licensing and registration process.
I hope to get some pictures posted this week end showing some of the details.
Thanks very much for such an informative write-up of your experience so far with the EVD Lithium! I look forward to seeing the photos... and hopefully reading more about your impressions of the EVD.
Here are some quick pictures
Handle bar set up
Rear disc brake, hub motor
Do these come with a motor number stamped in the hub motor?
Yes, there is a 6 digit number stamped on the hubmotor.
I now have close to 150 combined miles between the EVD and 3500Li. I still lean torwards the EVD it is great little scooter. I consider the EVD a 40 to 50mph scoot and the 3500Li a 30 to 40 mph scoot. I licensed and registered the EVD and I ride the 3500Li as a moped with no regisration. I carry a copy of the 3500Li MCO with the HP listed as 1.9.
I bought the EVD and the 3500Li for the LiFe batteries more than anything else. I can charge the packs up on the weekend and ride for a week before I have to charge again. I can easily accumulate 48+ miles before I have to recharge. The batteries maintain the charge without much voltage drop from day to day. I have both the EVD and 3500Li pack wired with balance lead harnesses to each cell and use an active balance charger to charge each cell to 3.65V. I have run both the 40AH and 60AH cells down to LVC on the scoots. The 60AH cells seem a little more robust and are well matched in the EVD pack. Starting out with a balanced pack each time you charge is important for me as the cells discharge pretty evenly.
The 21 cell 60AH pack for the EVD is comprised of 7 3 cell packs, 5 on the bottom and 2 on the top. Everything is well insulated and clamped down. The battery tray is the same size as the 3500Li.
Removal of the body work to get to the batteries is a challenge and is the worse part of both the 3500Li and EVD, as I have done both to get the balance lead harnesses installed. Removal of the center black section is a real pain, especially when you have to remove the windshield/ instrument cluster assembly to get at the screw that releases the ignition key bezel that will release the plastic body work.
After going thru this proceedure twice:If you have to remove the body work to replace a bad cell in your pack and you don't go thru and add the balance lead harness and some sort of BMS or balance charger at the same time "SHAME ON YOU"
The EVD is a great scooter. Handles great, has a nice ride with a suspension that works, brakes are great and the speed and range suites me just fine. I have to add the disclaimer that I ride at 4500 ft above sea level, the air is thinner with less resistance.
Gordon, I'm getting a low voltage warning under full throttle, and I'm suspicious that I may have a bad cell. So I'm going to pull off a bunch of body panels to do a voltage check on each cell. As you correctly point out, I should take the opportunity to wire up each cell. Any quick advice? Parts, wire size, etc?
I also have a bad cell rearing up its head in my pack. Cell 15 does not like to hold a charge and does not like to charge past 3.336V. So I guess I have to take it out and replace it with something that matches the rest of the pack.
The simplest form of balance lead wiring is to run a wire to each + terminal of each cell and one wire to the first - terminal in the pack then hook these up to 2 12 position terminal blocks in a sequential order so you can read off the voltages with a voltmeter. This would allow you to later hook up a BMS. Label each wire with cell# and plus or minus. I used 1/4 ring terminals and 22AWG wire.
My wiring in the EVD is a little more complicated as I am using balance chargers and I needed to split the pack into 3 7 cell packs, add balance leads and connectors, and add heavier gauge(14 AWG)charge wires to the + and - of each 7 cell pack.
The balance lead connectors I am using are used in the RC industry.
The balance chargers I am using are from FMA Direct CellPro 10S.
The balance chargers have been working great on both the 40ah and 60ah TS cells until the one cell in the EVD stopped taking and holding a charge.
I was asked to remove the pictures that I had posted showing the EVD battery compartment by the vendor, so those are no longer available.
It is a real shame that the vendors do not supply these lithium scooters with a wire harness that can be used to check and maintain these Lithium cells rather than leaving it up to the consumer to replace cells as they go bad and or install their own harnesses. Having a scooter sitting in the garage all apart waiting for a warranty replacement cell to arrive is not the best of situations.
The detailed graphics there are great, Gordon. Presumably if you wanted the same set-up for 20 batteries you'd just stick with 2 "packs" instead of 3, in much the same configuration?
And what does a balance charger do for you? I take this is not the same as a BMS?
I guess in part I'm looking for the best way to get close to doing a BMS system for the XM-3500Li's 20 battery set-up without having to resort to putting together circuit boards. Preferably at a somewhat reasonable price.
The low voltage light while operating the EVD is normal. On hills and under full acceleration the voltage drops. You can ignore most diag signals while riding. If you still have a diag code while you are stopped with the kickstand up, then you may have an issue.
One more thing...I just remembered that the last time a customer thought he had a bad cell it turned out the be the bank charger. You may want to check the output of the charger and cell individually and meter it separately.
I have a couple of questions about the EVD maybe one of you could answer. 1) What is the warranty on the scooter/batteries? 2) Is the throttle variable such that I could hold it at a lower speed, or does it just turn the motor on and off?