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Westcoast

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  1. Awesome! yes the mods were night/day with me. And agree completely on 3rd gear. Feels perfect about 90% of the time with me too. Only on really tight stuff I'll drop down to 2nd now. I feel I got a good bike too. Enjoy as much as possible!
  2. Sorry to resurrect a aging post. I am curious how you're making out on your bike. I am 1 year into a 2017 300 2T (my first trials bike) and I love it. After 4 months riding it completely stock and on the recommendations of experienced members of my club I installed a black (slow) throttle tube and a S3 low compression insert (gold colour). It moved the bike away from being overly snappy and jumpy beast into a completely predictable well behaved machine. And another bonus, it starts up much easier now, even in gear! It was a good bike before but now its smooth and amazing. No detectable loss of power either.
  3. Depending on how your kid rides, 10Ah wont help much. I'm sure you've discovered the standard SLA's at 10AH have horrible voltage drop during the 1st hour of use (even after 30 mins). You won't get double performance going with LiPO in the same amperage. I now have 16 5S LIPO packs wired into 2 8-pack bricks giving 42V 20A at full charge. We run 1 8-pack brick at a time. This solution is neither cost effective nor easy to manage but it does work. You need to actively monitor voltage during use (a meter on the bike) and know when to stop as RC LIPO's won't shut off for you. They'll just begin to destroy themselves. Also, I believe the 16 under load could pull up to 30A or so. Sure, watts/volts=amps says we should be around 21A with 12.8v SLA at full charge, but the ammeter on the bike suggests we can pull more than 25A. This isn't a problem with ordinary standard RC 25C LIPO packs designed for high discharge but definitely a problem with many pre-built packs with low amp BMS's. They'll fail. The pack you've found says the BMS can handle 25A but I don't see a peak value. If you were running only 1, I suspect it would blow the BMS, but 2 packs in para probably works. Oh, just noticed they are 185mm long which might be slightly too long for the tray on the 16 too. Savvy parents in the US have found these packs and use 2 in parallel (10Ah version): https://www.amazon.com/Electric-Battery-Lithium-LiFePO4-2000W-250W/dp/B096RRCD4F I'd go this route if I was doing it again from scratch. Order a pair and save a lot of management and charging hassle. And they are good battery chemistry being LiFePO4. Unfortunately the seller refuses to ship to Canada, I've asked.
  4. Follow-up for closure of this thread. Ordered a new motor from OSET USA (thanks guys!) and installed it. Performance is so much better. Sound wise, its noticeably a lot quieter. Without touching knobs there's more torque to the rear wheel and battery life seems better. My assumption at this point is the motor became contaminated so it started generating excessive heat and basically self-destructed. The shaft-seal looked fine when I disassembled but maybe dirt got in from between end caps and the body. I've sealed the new one a bit more. I'm monitoring temperature on the new one and during constant use after an hour its getting up to 50 degrees C. Problem solved.
  5. Thanks again for your insight. A new motor is the best option. It was a mystery why two Neodymium magnets lost all their magnetic ability so I did a little more research on effects of temperature on our motors. It seems we want to stay far away from the Curie Temperature value of 320C where permanent damage occurs. Ideally we should stay under 80C for best performance. In my case I believe it may have exceeded 300C, and on further inspection of armature wiring, it looks like I can see a small blob of melted copper! Thats insane heat. Does anyone know what normal operational temperature is? Also I might try to seal the new motor with some polyurethane to further weatherproof it but now I'm also considering a heat sink.
  6. Thank you for the info arthritic. I had a chance to pull the brush end-cap off this evening and theres 2 broken copper winding lines broken to the Commutator. Theres also some sign of light surface corrosion on the bearing at the brush-end too. The drive-side had none. Perhaps moisture is a contributing factor for the failure, or at least initiated it in some way. Would it be worth having the armature re-wound? Regarding magnets, of the 4 total two are well-adhered to the frame body and two dislodged. Interestingly, and very odd to me, the two which dislodged have almost NO magnetic properties. They wont self-adhere to the frame body at all nor attach to anything ferrous (a screwdriver, for example). Is this normal for these motors? I would have thought each of the 4 magnetic panels would be actual true magnets. Thanks again.
  7. Seems my lad was able to dislodge a motor magnet today. The motor is a 36V 900W version. Anyone seen anything like this before? Unfortunately he didn't mention the power change he felt until later and there wasn't any noise so we kept riding for about 10 minutes more. As the pic shows the motor became extremely hot. And amazingly, it still runs. I haven't disassembled the brush side yet. I am curious what the consensus is here. Can it be rebuilt (should it be?) or just replace it. At this moment it seems like a replace to me (I know nothing about electric motors) but I was curious if anyone has been here before. Looks pretty nasty to me. Thanks all for the advice.
  8. 4S are probably not what you want as they are 14.4V nominal and 16.8V full. I'm assuming you are thinking to run 4 of them in series to get over 48V. At full charge this is 67.2V, and that may harm your bike. I'm not certain what the OSET controller or throttle could handle, but why chance it running in the wrong voltage range. The person in that YT video uses 6S which are 22.2V nominal, 25.2V full. That would be a closer match to OSET spec. I didn't watch the video, just identifed his Turnigy packs. All hobby RC chargers will have a balance mode. Hobby LiPo's have no BMS therefore its all on you to do it right. You absolutely need to charge RC packs in balance every few charges. I balance charge EVERY charge. Also I keep a log book, and at each charge I also check starting balance V across all cells in the pack, note starting total V, and charging duration time so I know which packs are failing. You also need to accurately monitor voltage on the bike and know where your safe cut-off is. This is critical. You cannot use the throttle light indicators as they will not indicate proper state of charge on RC LiPo's. If you have a friend who understands RC LiPo safe handling, I would suggest you have him (or her!) give you a complete tutorial on storage, handling and charging of RC packs. LiPos are really safe when managed appropriately, and can really ruin your day or life when not. If you aren't sure what I mean, search fire proof LiPo charging bags on Amazon and read 1-star reviews. Theres some nice pictures too. Nothing like having 5' flames shooting up your wall to learn how not to manage LiPo's or why you want a really good charging plan! 😃
  9. Wow, the last thing I would say about OSET is they are poor quality. Judging from your decals and lack of hydraulic brakes, you must be running a pre-2013 model? You definitely cannot expect SLA batteries to last more than a couple years, unless you're keeping them topped up which every lead acid batt requires. OSET stock batteries are Yuasa's, Japanese brand. I dont think there's better SLA's out there. Heavy, yup. That part sucks but nature of the beast on SLA's. My kid's 16R is a 2016 and forks and shocks are good enough. Sure, brakes aren't top of the line HOPE or Shimano's, but are quite decent vs mechanical crap. I do wish the rotors were 140mm solid metal rather than 160mm light duty bicycle, but they are cheap enough to find online. No rotor guards on this year so I've replaced about 5 now over 3 years. OSET could put front _and_ rear disc guards on all bikes, not just front like on 20R and 24R's. How are you smashing so many throttle tubes? Throw on some 7/8's bar ends. $10 and yet to wreck a throttle tube here. And that bike has hit trees, been dropped down rock faces and is still 100%. Batt wise, I go 8x 5000mah 18.5v nominal, in 2S4P, so 20Ah. We get about 6km in 2.5 hrs on mixed hard/smooth single track and quit once the pack is down to 38V which is around 19V per pack. Balance (safe) charging is a bit of a PITA, but managable, just time consuming. I might start experimenting with a 36v (42v) bulk charger (no BMS, charge in a steel box) and see how far out of balance they get on each cycle then balance after a few charges. RC guys believe LiPo's are quite durable as long as you don't drain them down. They'll turn puffy soon as you do.
  10. For years I kept coming back to this thread hoping for some new information! And out of extreme need I decided to experiment so I can let others know what they can do for their kid's 16 which greatly improves their riding. Firstly, the info above is correct. Technically a 3.00x12 tire DOES fit. Like all dirt bike tires, it does take a bit of work getting the new tire on so I suggest leaving them in the sun for a few hours to soften the compound and use a bit of soapy water for lubricant. The OSET rims are not incredibly durable compared with a standard kids dirt or trials bike (say a Honda CRF70 or Beta 80). End result: I used a Shinko SR241 3.00x12 ($28 USD) and a Kenda 2.75-3.00x12 tube ($7 USD), running at 2-3 psi, all sourced from Rocky Mountain. And its working amazingly! https://www.rockymountainatvmc.com/tires-and-wheels/shinko-sr241-series-trials-tire-p?s=1247593 https://www.rockymountainatvmc.com/tires-and-wheels/kenda-motorcycle-tube-p?s=62843
  11. The following is my hack solution based on others who've gone before me and this has been working for 2 years now. I found the simplest path was to buy 4 x 5000mAh 5s 18.5v LiPo's from Hobby King, and run them with 2 serial/2 parallel wiring. I use standard RC chargers to provide balance charging. These packs give 37v nominal with 42v at full charge with 10A delivery and reduces your weight by at least 15lbs. I also converted all connectors to XT-90's to make it easy for myself. These packs are 3.7v per 1s and HK sells tiny beeping batt monitors (essential!!!) which hooks to each JST connector so you can have your child stop riding when the voltage drops to 3.6 or 3.7 (basically half way, settable on monitor). Now if I wanted to do a 48v, I'm not totally certain what path I'd choose at this point (for a OSET 20). If I go much further on this I might end up trying 18650 cell arrays with BMS, but HK does the job. Obviously this hack pack setup runs without proper low-votage cut-off which is considered critical for Li and its dangerous to run Li batts down completely. Please review what RC guys say about safety and treating their packs. Huge thanks to Gwhy and others on this forum who gave me knowledge, confidence and inspired me to take a chance on this stuff! I'm not a electrical guy and without the info on this forum I wouldn't have attempted it.
  12. Congrats on your very nice playground! Thats one way to solve a Canadian winter problem!
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