Brat73 7 Posted April 14, 2021 Hi so 1st lockdown last year brought a re-re brat built it loved it then stripped and rebuilt my original brat from when I was a kid along the way I brought lots of spare parts so building a third... my question is that I have an original brat with a 380 motor I want to upgrade to a 540 motor do I need to Change the gears to Cope with a 540 motor? And which 540 motor should I buy? thank you Share this post Link to post Share on other sites
KEV THE REV 2319 Posted April 14, 2021 The og SB is a fixed rear end - no diff. , so if you want to fit a 540 you can only alter gearing by means of the pinion . The re-re Brat has a diff to handle the extra 'power' and improve drivability . A stock 540 , Torque tuned or at most a Sport tuned are good motors for a fun ride . If you still have the old MSC fitted I wouldn't go much above these motors unless you fit a diff but then you are straying away from your og Brat and into re-re style which you already have .Personally I would leave the Brat with the 380 as stock and upgrade the 3rd Brat to 540 / ESC etc Share this post Link to post Share on other sites
Frog Jumper 3661 Posted April 14, 2021 58 minutes ago, Brat73 said: Hi so 1st lockdown last year brought a re-re brat built it loved it then stripped and rebuilt my original brat from when I was a kid along the way I brought lots of spare parts so building a third... my question is that I have an original brat with a 380 motor I want to upgrade to a 540 motor do I need to Change the gears to Cope with a 540 motor? And which 540 motor should I buy? thank you Any motor should fit, once you remove the plastic motor plate. A simple silver can should be plenty fast. The real question is what pinion. Do you know the teeth-count of the Counter Gear in the particular car you want to upgrade??? That is the number of teeth on the outer gear - the one that contacts the pinion gear. Terry Share this post Link to post Share on other sites
markbt73 5316 Posted April 14, 2021 If memory serves, the stock Brat internal gearing is the same as the "fast" Frog set - so an 18 tooth pinion should work. Motor bolts straight on to the gearbox, no adapter needed. 1 Share this post Link to post Share on other sites
Brat73 7 Posted April 14, 2021 Thank you for replying my re-re brat has a 540 and I (my dad...!) upgraded my original brat back In the day to a 540. So I want to do the same to this one. I want to keep it as original as possible so won’t fit a diff so will get a sport tuned do I go brushless? Forgive me not sure really what that means! Also not 100% sure what you mean by MSC.? Share this post Link to post Share on other sites
Brat73 7 Posted April 14, 2021 Thank you frog jumper and markbt73 I will check the pinion numbers if it is 18 I will buy a 540 motor bolt it on and see what happens...need to buy a ecu and servo yet. Any thing else I need to consider? As you may have guessed somewhat of a novice but I am hooked again like I was when I was 10...! Share this post Link to post Share on other sites
KEV THE REV 2319 Posted April 14, 2021 15 minutes ago, Brat73 said: Thank you for replying my re-re brat has a 540 and I (my dad...!) upgraded my original brat back In the day to a 540. So I want to do the same to this one. I want to keep it as original as possible so won’t fit a diff so will get a sport tuned do I go brushless? Forgive me not sure really what that means! Also not 100% sure what you mean by MSC.? You don't need a brushless set up , a stock motor , or TT or ST as I said before will be plenty - these are brushed motors . A Hobbywing Quic-run 1060 will be a suitable ESC to take the place of your old Manual Speed Controller ( the small board with the wiper arm and contacts ) / resistors and throttle servo . You might also consider a 2.4ghz radio set-up while you're at it or you can use your old 27mhz set if your happy with it . Share this post Link to post Share on other sites
Brat73 7 Posted April 14, 2021 Thanks Kev i see yes my old one has an MSC but the shell on the one I am building doesn’t so will get one of those. I really appreciate your help. Cheers Share this post Link to post Share on other sites
Willy iine 18805 Posted April 15, 2021 I would stick with a silver can. Next thing you know with more power your axles start to slip. I had that problem when I owned the original Brat back then because I drove the thing so often. I loved the car. Share this post Link to post Share on other sites
Brat73 7 Posted April 15, 2021 Sorry, silver can? You mean the original motor? Share this post Link to post Share on other sites
Willy iine 18805 Posted April 15, 2021 14 minutes ago, Brat73 said: Sorry, silver can? You mean the original motor? Maybe it is a USA thing. We call the Mabuchi/Johnson 540 motors 'silver cans'. Share this post Link to post Share on other sites
