Seanster43 222 Posted October 16, 2020 Hello, recently got ahold of an 88t spur i know it’s 0.4 pitch just wondering what’s the lowest I can get pinion wise to match. I had had a nosey on here and now I seem even more confused 😂I was under the impression that bigger pinion and smaller spur would make more top end but I guess there’s more to it than that. Any help or info would be appreciated. I’m after high top speed for a project if that helps. Cheers Sean Share this post Link to post Share on other sites
TwistedxSlayer 1290 Posted October 16, 2020 I was also under than impression too. Share this post Link to post Share on other sites
Jonathon Gillham 4595 Posted October 17, 2020 8 hours ago, Seanster43 said: Hello, recently got ahold of an 88t spur i know it’s 0.4 pitch just wondering what’s the lowest I can get pinion wise to match. I had had a nosey on here and now I seem even more confused 😂I was under the impression that bigger pinion and smaller spur would make more top end but I guess there’s more to it than that. Any help or info would be appreciated. I’m after high top speed for a project if that helps. Cheers Sean Yes thats right, smaller spur and/or bigger pinion gives more top speed. Gearing is a balancing act between top speed, acceleration and heat. What sort of motor are you running? Find a suggested gearing chart for the motor and start from there. Then there are other factors like amount of timing on the motor, size and layout of the track/bashing area, 2wd or 4wd, weight of the car and what you prefer or are trying to achieve. My TA07 runs an fdr of about 3.6 in 21.5T blinky class. This is a 63T spur, 36T pinion and a different centre pulley to reduce the internal ratio to 1.85 (the IR is right, pretty sure the other numbers are right but could be out by a teeth or 2). The formula is Spur / Pinion X Internal Ratio (which can be found in the manual). Check though how much room you have too. You may not be able to fit a preferred combo in there due to the sizes. .4mod /64dp are small gears, 48p/.6mod in the middle and 32p/.8mod are big. I run 48p in all my cars. If you are running agressive gearing its best to start out conservative then keep increasing timing or pinion and check the temperature after a few minutes run time. If you can tell us what motor you are running, whether its blinky or has ESC timing and what you're doing with the car then a few people on here will be able to give better answers 1 Share this post Link to post Share on other sites
Seanster43 222 Posted October 17, 2020 Nice one cheers for the reply I’ve got a Leopard v2 speedo and a Turnigy Trackstar 10t motor, the plans were to see what top speed could be achieved on the tb-01 chassis. Got loads of different spurs as well so was more of a project for fun. I appreciate there is more to it than just a spur/pinion combo so still trying to look at other factors and still learning loads as I go. Share this post Link to post Share on other sites
Fuijo 867 Posted October 17, 2020 The internal gear ratio is 2.6. So to get your FDR (spur teeth divided by pinion teeth) x 2.6. What FDR you need will depend on whether you are running the plastic drivetrain, the metal drivetrain, or a combination of both. I would gear a 10t brushless motor about the same as a Superstock RZ/TZ, but if you are using the metal diff crown gears you may have to go lower still. Share this post Link to post Share on other sites
Seanster43 222 Posted October 17, 2020 Metal gears getting used also got a tz/rz motor so got a few options. Yeah no way would I run that on the plastic gears 😂 Share this post Link to post Share on other sites
qatmix 794 Posted October 17, 2020 It would quicker and better for the motor with the plastic gears. They would have no problems with those motors. Share this post Link to post Share on other sites
Seanster43 222 Posted October 17, 2020 Got a donor car with plastic gears too so lots of option initially thought power with the metal gears on the carbon chassis would be wise so will be a bit of trial and error I guess, interesting to hear that the brushless 10t is on a par with with RZ/TZ motors. What speedo would you guys recommend as won’t be using my phone lol . 1 Share this post Link to post Share on other sites
Fuijo 867 Posted October 17, 2020 2 hours ago, Seanster43 said: interesting to hear that the brushless 10t is on a par with with RZ/TZ motors It isn't. But the gearing may well be, at least as a starting point. If the motor/ESC gets hot then fit a larger spur or smaller pinion until it doesn't. If it reaches top speed too quickly, fit a smaller spur or larger pinion. 1 Share this post Link to post Share on other sites
Seanster43 222 Posted October 17, 2020 Yeah fair point lots of trial and error I guess. Share this post Link to post Share on other sites
TwistedxSlayer 1290 Posted October 20, 2020 But please let us know how you get on with it. Share this post Link to post Share on other sites
Seanster43 222 Posted November 24, 2020 This is where we’re at now, fitted the carbon prop shaft with steel splines, new wheels and tyres are on. Sorry I’m always slow with updates these days as busy with work and the wee one. Got a few more gearing options. Noticed there is a 37t steel 0.4 pinion this should be a good starting point with the 88t spur then I will take it from there. Been tied up with other projects too. So will hopefully get this out at the weekend for it’s first run. Still to do, Fit Alloy Steering Parts Drill Chassis For Battery Holder Change Spur & Pinion Over Decide on Bodyshell 1 Share this post Link to post Share on other sites