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A 2018 Mid-Year Message From Storm Sondors Read more... ×


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MattRobertson last won the day on June 30

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About MattRobertson

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  1. MattRobertson

    Sondors Fat (Custom) loses power

    Unfortunately this is a not-uncommon problem. Over time some terminals work loose. Typically the terminal that is stuck is beyond repair. Yours sounds like it was in the early stages as you didn't report any arc'ing, serious melting and you didn't let any smoke out. You got out easier than most in that you had spare parts in hand and you knew how to swap things around. Usually someone has to wait for another cradle to arrive. For future reference here is one replacement cradle https://lunacycle.com/cradle/ Be careful when you buy from other vendors as these bottle batteries are sold in many different lengths and the cradle you find somewhere else may not fit a Sondors. p.s. in some cases the cause has been traced to the operator not properly seating the battery. Make sure yours is locked in and seated properly before you ride.
  2. MattRobertson

    Need new battery charger 48 volt

    For the Luna chargers, go to EBay and search for "xt60 female to barrel plug adapter" and you will see a wide variety of adapters that will keep you from having to cut any wires. This is the one I use but its sold out at Luna. https://lunacycle.com/xt60-female-to-barrel-male-plug/
  3. I don't know about cheap but Pasion Ebike is a known 'good' vendor in that it is run by a well known member of the Sondors community (Wendy Xie) and she is completely reliable in everyone's experience. Look for her shop on Aliexpress. If she doesn't have a bare 750w motor on the site message the store and ask for one. You can also msg her directly on Facebook but probably it is better to go thru Ali
  4. MattRobertson

    2018 sondors fat tire upgrades.

    Marco you figured out the secret sauce to fitting a bigger battery. The 17.5ah 'new' triangle size exists so that people who don't feel comfy dremeling their battery box have something they can fit in directly. As you have discovered, if you cut away the ribbing you can easily fit the earlier generation 20.5ah triangles... If you are really adventurous you can also move the controller outside the box and fit in a REALLY big battery. Biknut did that and is running a 48v, 30ah monster in his battery box. First rule of gunsmithing: Its a whole lot easier to file metal off than it is to put it back on again. Similar rule in battery box cutting
  5. MattRobertson

    2018 sondors fat tire upgrades.

    Not that particular upgrade. A hint: I have two 35a controllers hiding from sight. :-)
  6. MattRobertson

    fat tire motor question

    The mac motors are not going to be able to do much for you in terms of power. They are available in different windings but none of them are going to provide high speed and high torque on a 29" OD, 26" wheel. I looked at doing an AWD build with dual Mac motors and they just won't cut it. Also a Kelly controller is going to be great so long as you do not want pedal assist. If you want PAS you MIGHT be able to use one of the ASI controllers Luna is selling with their Mac motor kits. Another reason not to do a Mac motor. For your Sondors, if you want the same kind of speed most everyone raves about, Do a Bafang fat 750w geared hub motor. Works great with a 52v battery. If you want to take things to the next level you can do a 60v battery and couple it to a 60v compatible KT-LCD3 display (same as all Sondors models late 2017 and earlier) and a KT 35 amp 60v capable controller. You will have a bike that hits 40 mph.
  7. MattRobertson

    Front tire hits frame

    Joe the problem you are reporting is uncommon but you are far from the first to have it. First of all, make sure the tire bead is seated correctly. Thats the most common cause but not your problem if you see a side bulge. You will learn real fast these tires practically fall off the rims without pressure so don't worry about having to fight it like you do on smaller tire'd bikes. What it sounds like you have: on occasion Chaoyang makes a tire whose casing has a 'jig' in it. The abnormality will not necessarily evidence itself right away. And generally it is more annoying than it is an actual problem. My December-2016-delivered bike's rear tire had this problem. I know my way around a bike and bike tools, and I did everything possible to ensure I did not have a bead seating problem, and that the underlying tube did not somehow have an issue. In the end I determined the issue was localized to the tire casing itself. I changed the tire and the issue disappeared. Its actually easy to ascertain if its the tire or the rim. Get the tire up off the ground and spin it. Does the rim have a jig or is it true? If the latter and the tire is wiggling... whatever it is thats going on is not the rim. My issue surfaced after about a thousand miles of riding. In your case, I would not be surprised if it came about when you exceeded the recommended tire pressure by 50%. Don't do that :-). 20 psi is essentially hard as a rock for tires like these. If you have to buy a replacement tire, JensonUSA sells Arisun Big Fatty tires. Arisun is Chaoyang's US and EU brand. Its the same tire. the 30 tpi wire bead tire is extremely durable and costs less than $50. If you want to go apples for apples, get the folding 60tpi tire. Will run you about $100.
  8. MattRobertson

    2018 sondors fat tire upgrades.

    If you have a Sondors delivered with a triangle battery, the biggest battery you can fit in its place is 52v, 17.5ah sold on electrobikeworld. Worth noting: The Sondors 48v 17.5ah battery is a direct fit and much lower cost, although it has less performance (lighter duty BMS and lower voltage). If you have a Sondors delivered with a bottle battery, then you can fit in a 20.5ah 52v aftermarket battery. In both cases, the 25a controller is as big as you can go without a motor upgrade or some creative, detailed soldering work.
  9. MattRobertson

    Anyone use the Fahgettaboudit chain.

    Chains like this are heavy but manageable. Its the way I have chosen to go given that angle grinders can get into ANYTHING in seconds and cables and even U locks are effectively worthless. You would do better with the Pragmasis chain, which uses longer links and as such is lighter weight with no loss of strength. Its also stronger than the Fahgettaboudit. Its also available in longer lengths, or shorter per your needs. I use the 13mm 2-meter chain and a motorcycle disc lock that is extremely difficult to get at with tools. You can go bananas and get bigger chains as well. http://lockitt.com/protector-chain-13mm.html http://lockitt.com/RL21-roundlock.html Not cheap but much more effective than the route you are describing. A New York lock like usually used with a Fahgettaboudit takes about 45 seconds to get thru with an angle grinder. The motorcycle lock really isn't vulnerable at all to a grinder (it spins freely) and getting thru the Pragmasis chain takes about triple that time... which is still not a lot. However, its an imposing sight and a strong argument for someone to steal the bike or car next to mine.
  10. MattRobertson

    chainring upgrade for fat x 7

    You will need a complete crankset replacement. The stock cranks do not support chainring swaps. You will need a crank puller. You will also need to replace the chain as you need one more link for every tooth you add to the front ring on your new crankarms. KMC chains seem to be the hands down favorite for durability and value these days. Most folks go to Amazon for a replacement crankset. Probably your best bet is to find a fixie crankset as they seem to be the only ones designed for a single front chainring, then swap in the 3/32-compatible chainring of your choice.
  11. MattRobertson

    Sondors X to Wolfenbüttel, Germany

    Deliveries to Europe are relatively recent and at a smaller scale than the U.S. deliveries. My daughter lives just outside of Brussels. She and my son-in-law both have matching Original X models. They report the same thing.
  12. MattRobertson


    Single speed is perfect so long as you don't have hills. the problem is you are expecting the motor - which has little nylon planetary gears inside of it that take all the punishment - to shoulder ALL of the propulsion burden. Since there are no free lunches in the world, you are going to have to help that hub motor get up the hill. For that you are going to need gears because you are going to have to pedal. Here's what you want to be thinking about when comparing the Sondors to a Rad: The Sondors is easily upgradeable. I mention this because volts are volts and amps are amps and the Rad is no better able to handle grades than the Sondors. But since the Sondors is easily upgradeable to provide better torque, it is your better choice. First of all, power to the ground is a straight function of watts vs. amps. the watts come from the battery and the amps come from the controller. The fact that the Rad has a 750w rated motor is meaningless to its output. It and the 500w Bafang are both going to put the same power to the ground and both have the identical internal gears.. the 750w motor is more upgradeable than the 500 (both are WAY underrated and can handle a lot more than either manufacturer is handing to them). So... the Rad mini has a 48v battery and a 22a (peak) controller. 48 * 22 = 1056 watts are actually getting put to the ground. BTW 48v is a 'nominal' number. 48v batteries are actually 54.6v when fully charged, but lets just pretend its 48v as advertised and do the same apples/apples math for both bikes. The Fold X has a 48v battery and a 15a controller. Clearly less. BUT a 25a (peak) aftermarket controller is readily available. Cost is about $60 but you also need to buy a revised display and throttle. Overall cost is about $125. So now a Fold X's power output is 48x * 25a = 1200. About 12% more power. In automotive terms, voltage is horsepower and amps are torque, so you are getting that 12% exactly where you need it to do a better job of climbing hills. So... cost comparison A sondors Folx X7 is 1199 delivered. Add $125 for the upgrade to take the Sondors into higher performance territory. A Rad Mini is 1499 delivered. Rad cost is 12% more. Also RadMini weighs 60 lbs. Sondors Fold X 7 is 50 lbs. That 10 lbs is going to count against the Rad's ability to move it and you up a hill. So the Rad costs 12% more and has 12% less power, to move a bike that is 17% heavier. By the numbers, the Sondors Fold wins against the Mini. The Sondors Original X wins in a much bigger way because you can give it a 25a controller AND a 52v (or even a 60v) battery. At that point you have a hot rod that the Rad can't even touch. Check this out: Buy a Sondors Original for $879 delivered. Remove the battery, controller and display (throttle will still be compatible) and upgrade the controller and display as described above for around $115. Then upgrade the battery to a 17.5ah, 52v battery. Thats a pretty penny at another $589. You end up with +879 Bike +115 Display and 25a controller +589 17.5ah 52v battery -350 what you can sell the original battery and controller/display for. Before you sell off the excess new parts, you are at 1589. With the $350 sale (there is a booming market for original parts on the Facebook support group) you are at 1233. The Rad Rover is $1499 and its 22a controller and 48v battery puts out the same nominal 1056 watts. The Sondors on the other hand is single speed, and 52v x 25a=1300 watts. And its 17.5 ah battery is well beyond the 14ah on the Rover. Food for thought. Forget the brand names and advertising claims and remember volts are volts and amps are amps.
  13. MattRobertson

    My speedometer isn't registering

    Worth noting in your parts searches: Velomobileshop.com is Kyle Chittock, who is effectively the U.S. distributor for the products made available by Pasion Ebike... which is owned by Wendy Xie. Buying from Wendy/Pasion on AliExpress will net you *exactly* the same product as those purchased from Kyle/Velomibileshop. Except if you are in the U.S. and order from Kyle you are going to get your products in a few days versus 2-4 weeks direct from Wendy in China. If Kyle is sold out in the USA, Wendy very likely is not (but drop a line to Kyle @ his facebook group and often as not he has just not updated his web site, or has a unit or two in reserve he will let you have). Both vendors are as completely reliable as you can get. I once received a throttle with a bad connector from Wendy and a single email to them via the Ali message center and they a) apologized profusely and b) immediately mailed me a correct replacement. I can't help but note that the Kunteng 'KT' displays and controllers that were the Sondors mainstays for the first couple of years seemed to be completely reliable, while the newer KD-51C from Tianjin seem to be occasionally problematic. Reverting back to KT controllers would not be a bad thing, especially since you can increase your controller max amperage from 15a to 25a.
  14. MattRobertson

    L48v 20.3ah battery charging problem.

    Two models to choose from unless you want to get weird and pick one with very low amperage or very high amperage With a 48v battery I would buy this one. Now while they are still available at $40 with free shipping. http://r.ebay.com/VHupCi This assumes you are in the USA of course. You could also use a CLG-150-48A but its 150-watt rating means it has to be kept at lower amps. However if you want to charge a 36v battery thats the one you have to have. And yes they can do 80, 90 or 100%... its up to you to dial it manually. These chargers are most conveniently used at a single preset setting (unless you can find a dial for them and then put hashmarks for set percentages). One of the risks you take going this route is dialing the wrong voltage. You can overcharge with one of these. So there's a level of responsibility you have to accept. But to me its worth it. I have one of these HLGs dialed to 58.5v and 3.1a. Basically a 185w max-unit-capacity setting. Its the one I travel with on one of my bikes. I set it to 58.5 to ensure if I screw something up its not going to exceed 58.8v. Bear in mind meters like a Watts Up are notorious for being a little off in one direction or the other. Don't trust it until you have established how far off it is and can compensate for it. Small differences for other devices are magnified in a charging application where small changes matter a lot.
  15. MattRobertson

    L48v 20.3ah battery charging problem.

    I'm putting something together using a new charger I am making up for a new location I am setting up. It should pop up in a week or two.

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