Redback Posted February 5, 2021 Author Share Posted February 5, 2021 I didn't try the higher amp esc with the small motor, but i would say the xerun combo vs the ezrun combo is night and day on power delivery on stock settings. Smoother stronger power output, miles of torque and lots more breaking ability if things go wrong. I wouldn't have expect anything less from a expensive race esc. The big benefit is how light the higher amp esc is vs the ezrun. Intresting on the pinion and spur sizes and dps, I have bought 4 diffrent pinions and spurs and the results will be the same 🤦♂️ Quote Link to comment Share on other sites More sharing options...
Redback Posted February 6, 2021 Author Share Posted February 6, 2021 Same setup as yesterday, just found a bit more room to try and max it, its still got more to give however the carpark was just to rough, completely shredded the front of the body shell. Hit the first goal of 50, can see it getting to 60 with enough of a run up, maybe eek close to 70 if i mess with the motor timings and turbo boost, but that will come later. New lighter plastic beadlocks held strong, might get another set of the fast trax tires for road testing as they are the only ones that seem to fit on the beadlocks. Tamiya and HPI tires wont fit. 1 Quote Link to comment Share on other sites More sharing options...
Derka Posted February 6, 2021 Share Posted February 6, 2021 That data logging is cool. What is it? Your temperatures are are great, barely warm so you have a some head room there. How close is that 79,415 rpm to the max of your motor? 1 Quote Link to comment Share on other sites More sharing options...
Redback Posted February 6, 2021 Author Share Posted February 6, 2021 I use the sky rc data and convert it, then make it pretty with this website.https://www.gpsvisualizer.com/profile_input Here are the temps from yesterdays test run. Only the xerun gets me this data, the ezrun is guess the numbers. So looks like battery was a bit cold running this morning at -1c got over 90,000 rpm yesterday. Still have 50% of the pack left. 1 Quote Link to comment Share on other sites More sharing options...
Lone-wolf Posted February 6, 2021 Share Posted February 6, 2021 As you know a battery warms slightly as you use it so may get more once its a 3rd down 1 Quote Link to comment Share on other sites More sharing options...
Lone-wolf Posted February 6, 2021 Share Posted February 6, 2021 As your car started out as a drift car could it have lower native gearing, just a thought 1 Quote Link to comment Share on other sites More sharing options...
Redback Posted February 6, 2021 Author Share Posted February 6, 2021 Indeed and testing on warmer days helps, so that means it could have gone faster if the car park wasnt destroying the car. Running without the front splitter results in this, its poor front lip got road burn. Really scraping the bottom of the drum looking for spurs that might fit that are much smaller than the "stock" ones (inc RW spurs) the ones that seem the right tooth count seem to be on a 4-5mm shaft rather than the thinner shaft used on the carnage/vantage (3mm) Found some 40t pinions but not on 5mm shaft, really dont want to pull the 4700kv 3665 motor from the lads outlaw just to hit 70 and not even sure a 40t would fit, 30t is getting close to the limit of what the motor mount will support on stock diameter spur. Brain fart incomming. Sooo custom motor mount needed? I dont want to change the motor / esc timings yet, i want to get to 60 without breaking a sweat with drive train changes before tweaking the motor. I have a smaller 1406 5700kv sensored castle in my outlaw i can try but its not rated for 4s so 3s would be the max, i think with that and the mamba x esc i might hit 60 without pinion or spur changes. Just worry the castle motor is a bit small for the power im demanding from it but i know its got more motor than the 3652 i got 47mph from before and if i swap to the castle setup then the xerun becomes a shelf spare again, that seems to run really well on this chassis. Oh and turns out the 53mph run also shredded a tire, not going to test on that car park again, this had to be the breaking at the end of the pass, as it was just sliding all over loose tarmac stones. 1 Quote Link to comment Share on other sites More sharing options...
Redback Posted February 6, 2021 Author Share Posted February 6, 2021 5 minutes ago, Jack Reacher said: As your car started out as a drift car could it have lower native gearing, just a thought It was geared quite high imo 30t pinion, the spur is the same as in the vantage and carnage along with its aftermarket options. The diffs are the same as the vantage and outlaw, the only diffrence is 17t pinion on the carnage and vantage as they have bigger wheels. 1 Quote Link to comment Share on other sites More sharing options...
Redback Posted February 8, 2021 Author Share Posted February 8, 2021 Got desperate on spur gears, as the trx4 runs 32dp i wondered if their spurs would fit and looks like they do. Next run will be a 34t pinion on a 39t spur oh my this thing going to gooooooo. 1 Quote Link to comment Share on other sites More sharing options...
Lone-wolf Posted February 8, 2021 Share Posted February 8, 2021 If that dont do it nowt will, go for it Quote Link to comment Share on other sites More sharing options...
Popular Post Redback Posted February 12, 2021 Author Popular Post Share Posted February 12, 2021 (edited) High speed gears arrived, no other changes, hit 61mph on 3s with ease didnt even get close to maxing it at most this was 60 - 70 throttle. New personal best, 9mph off the target, easily will do 70+ without any further changes. 4s is the next step along with motor timing changes, will post updated build pics later. Edit: Some tastey data. Chuffed to bits 🙂 Edited February 12, 2021 by Redback 3 1 Quote Link to comment Share on other sites More sharing options...
Stormbringer Posted February 12, 2021 Share Posted February 12, 2021 that was flying there 1 Quote Link to comment Share on other sites More sharing options...
Lone-wolf Posted February 12, 2021 Share Posted February 12, 2021 Redback, that is brilliant, and i think its fair to say you now own the worlds fastest FTX Bansai, well done you for sticking with it, looking forward to seeing you hit target speed 1 Quote Link to comment Share on other sites More sharing options...
Alex97 Posted February 12, 2021 Share Posted February 12, 2021 Congratulations 👏 1 Quote Link to comment Share on other sites More sharing options...
Redback Posted February 12, 2021 Author Share Posted February 12, 2021 To fit in the bigger pinion need to cut the chassis a bit here. The Traxxas spur didnt hold up as good i had hoped, might have a nother couple of runs in it, its a tad deeper than a stock one so cant use slipper pads. or the shaft pins wouldnt hold the slipper plates. Might need to find a new way delivering the power to the drive cups, this driveshaft is going to be a failurepoint, not sure if it was damaged from the run, but as i held it in the air and spun the car up to see how the tires react at near max rpm, i noticed the car vibrate then it got worse and worse. No more speed runs for a little bit. Good start and impressed it handeled the power its already been fed. 2 Quote Link to comment Share on other sites More sharing options...
Redback Posted February 12, 2021 Author Share Posted February 12, 2021 (edited) As the batteries arrived, thought i would see if they fit as begun to think they might be to deep. 4s yet to be tested but getting decent mha 4s batteries in these little cars seems tricky, I went with 2x 100c 4s 1600mha drone / flight packs. They just fit. There is literally 2mm space before they would be hitting the top brace, got lucky. I will run them in parallel to make 3200mha should be enough for a good couple of runs and hoping having it drain from 2 battery sag will be minimal. Time will tell. Edited February 12, 2021 by Redback I can't spell 3 Quote Link to comment Share on other sites More sharing options...
Lone-wolf Posted February 12, 2021 Share Posted February 12, 2021 they fit just dandy, you really are on course to get every little bit out of this car, well done 2 Quote Link to comment Share on other sites More sharing options...
Stormbringer Posted February 12, 2021 Share Posted February 12, 2021 Really hope hope you reach your target speed mate really fascinating thread this 1 1 Quote Link to comment Share on other sites More sharing options...
Redback Posted February 18, 2021 Author Share Posted February 18, 2021 (edited) Got an even smaller spur that might fit, got to try and fix the oscillation on the drive shaft as this is bending slipper shafts and that in turn is stopping me right now pushing the car past 60. Theres tons of steering slop from the servo, This is causing wheel vibrations at high speed making it skittish, so servo upgrade is a must. There is also a fair bit of slop in the servo saver post and arm bushings. Removing this should help with high speed vibrations passing into the driveshaft. or thats a theory. Sorex wheels are now on after peeling the rally blocks off the crawler beadlocks, they did very well making it to 61mph imo. Prepped a little battery adaptor just gotta wait a little longer to sort out my battery issues, to run full parallel capacity, but got ok run time off one. 4s 1600mha about 10 - 15 min 30 -50% throttle all the time (drifting). Edited February 18, 2021 by Redback 2 Quote Link to comment Share on other sites More sharing options...
Popular Post Redback Posted February 19, 2021 Author Popular Post Share Posted February 19, 2021 (edited) I picked up a 2nd motor mount wondering if it could be used to hold a bearing for the drive shaft. As the motor and drive train oscillate it causes the drive shaft to shift slightly causing a vibration that causes a cascading failure. It bends a little then a lot as the motor spins the drive shaft to 100,000 rpm. As the bearings and shaft didnt work out, it looked like with some cutting it might still be of use as a bearing holder to hold the slipper drive shaft cup. This is the part that starts to flex under loads bending the shaft as shown above. Solution found perhapse. Take your brand new motor mount. Chop out this useless bit. Put it in, dont forget to get the little plastic bearing cap, it doesnt come with the mount boo hoo. Secure top plate. Bang on!, now to stop the bearing coming out / loose, part 2 tomorrow. Screw / mount from the bottom, fabricate metal plate for supporting top screws and brace. Should be good to test. Edited February 19, 2021 by Redback 4 Quote Link to comment Share on other sites More sharing options...
Lone-wolf Posted February 19, 2021 Share Posted February 19, 2021 great solution looks ideal 1 Quote Link to comment Share on other sites More sharing options...
Redback Posted February 22, 2021 Author Share Posted February 22, 2021 (edited) Servo upgrade, doesnt move unless told unlike the stock one that had tons of play. Had to trim some of the chassis to fit in the servo what a pain, ftx love to use weird servo shapes and there for wierd chassis stiffening that makes you have to cut stuff, will be getting a carbon fiber chassis i think. Anti oscillation mod v1 completed with light testing and still using the bent shaft there is no vibrations or wobble. Restrained the bearing with shrinkwrap with a stiff foam block to keep the bearing inplace. Secured to the top brace and the chassis. Just waiting on another 4s battery, ergo the lack of real progress. Would love some reccomendations for 100c 4s batteries 3200mha + that arnt really tall. Edited February 22, 2021 by Redback 1 Quote Link to comment Share on other sites More sharing options...
Lone-wolf Posted February 22, 2021 Share Posted February 22, 2021 Regards battery can you raise the posts on the battery holder like fit a spacer under each post with longer screws, I'm now really thinking I will.end up getting a Hoboa hyper GT roller later in year Quote Link to comment Share on other sites More sharing options...
Redback Posted February 22, 2021 Author Share Posted February 22, 2021 1 minute ago, Jack Reacher said: Regards battery can you raise the posts on the battery holder like fit a spacer under each post with longer screws, I'm now really thinking I will.end up getting a Hoboa hyper GT roller later in year Not without hitting the top center brace, that limits the height. it overhangs the battery tray slightly would have to chop some out and dont really want to keep cutting away parts of the car 😛 1 Quote Link to comment Share on other sites More sharing options...
Popular Post Redback Posted February 23, 2021 Author Popular Post Share Posted February 23, 2021 (edited) Gave the drive shaft mod a propper test, using the same setup as the 61mph run, just with smaller sorex tires, so geared down a little if anything. First up some tastey data, esc got a bit warm this time but nothing close to failure. Managed to max it this time. 3s power! 80mph, beat my personal best by 19mph, smashed the 70mph goal, so the next goal is 100. On 4s i think i 100mph is doable. Very happy with this result, if it doesnt go faster im not fussed, hit my goal then some. Edited February 23, 2021 by Redback 5 Quote Link to comment Share on other sites More sharing options...
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