bofin 0 Posted March 2, 2009 right ive bought a used manta ray off ebay and after only 5 to 10 mins of driving the motor is extremely hot and the escape aswell.it thermalled using a sport tuned with a 19t pinion and a tamiya 101 esc.it also does the same with the standard motor . the dirt tuned motor runs very hot but hasnt themaled yet.as i bought it second hand i dont know the hisory of it i can tell you its fully ball raced and thats it.it may be easier if someone can tell me the best pinion /spur gear to use to keep it suited to offroad .also can someone tell me where i can get a 17mm hex adapter that will fit a tamiya thanks. Share this post Link to post Share on other sites
TA-Mark 195 Posted March 2, 2009 19T pinion/ 74T spur would be ideal gearing for your motors. Pull the motor out, check how easily the chassis rolls, it should roll away very easliy with no resistance at all with no motor. Only thing I can think of is you have something binding. Overtightening the wheel nuts can force the plastic hexes tight up against the side of the bearing sheilds. Gearbox full of water/dirt will do it. A failed bearing will cause a bind too. Share this post Link to post Share on other sites
terry.sc 16 Posted March 3, 2009 As Mark says, something is binding in the transmission somewhere. Just a process of elimination to find out where it is. Motor out to see if it rolls, pop out the propshaft to check if it's front or rear, keep going until you find the problem. Share this post Link to post Share on other sites
bofin 0 Posted March 3, 2009 thanks for that ill strip it clean it regrease the bearings also noticed the alloy gears so ill replace them.any info on the 17mm hex drives? Share this post Link to post Share on other sites
adam1973 1 Posted March 3, 2009 You need 12mm hexes not 17mm. Look on ebay for them. I got a few sets a while ago, I can't remember what make they are, but they're an alloy clamp type like these; http://cgi.ebay.co.uk/Alloy-Wheel-Adapter-...1QQcmdZViewItem Share this post Link to post Share on other sites
bofin 0 Posted March 3, 2009 You need 12mm hexes not 17mm. Look on ebay for them. I got a few sets a while ago, I can't remember what make they are, but they're an alloy clamp type like these; http://cgi.ebay.co.uk/Alloy-Wheel-Adapter-...1QQcmdZViewItem i know what hexes tamiya use i want 17 mm so i can mess with other brands that have far more choice of wheel Share this post Link to post Share on other sites
twisty 8 Posted March 3, 2009 If you have been or intend to use larger diameter wheels n tyres it will gear the car up,causing more load on the motor and ESC. As the others have said though,it is most important to have a free wheeling drive train. Share this post Link to post Share on other sites
terry.sc 16 Posted March 3, 2009 For a Manta Ray the biggest choice of other manufacturers wheels in 2.2 diameter have the standard 12mm hex. As Twisty says, if you are looking at wheels with a 17mm hex you are looking at wheels and tyres up to twice the diameter of the kit tyres, which you will have to compensate for by fitting a much smaller pinion, if you can go low enough. Share this post Link to post Share on other sites
WillyChang 1812 Posted March 4, 2009 putting larger dia wheels on is a BAAAAAD idea... drivetrain will suffer & die early death if you've been overheating for a while your plastic motor mount has probably melted & is running untrue anything used that you don't know the providence of, its worth pulling apart to check & rebuild. Wouldn't be the first time something is promised as "fully ballraced" ... isn't! (or you'll get excuses like "Yes but i changed all the 1150s to bearings!"... but what about the 850s?!) Or maybe the BBs *just* got put in, like a day before the sale... and its spent its first life running shot bushings. Open the rear gearbox and check the condition of the gears - they could be all worn sharp. Rear gearbox & lid can also crack and the gears will skip around. ---> you really don't wanna put larger wheels on! Share this post Link to post Share on other sites
adam1973 1 Posted March 4, 2009 I think that the biggest wheel that you'll get away with is the 2.2 sized HPI Yokohoma Geolander, but use a small pinion like a 16 or 17. Also, fit a motor heatsink as well, one might not be listed, but a narrow one like this one; http://www.modelsport.co.uk/?CallFunction=...mp;ItemID=12813 or this one; http://www.modelsport.co.uk/?CallFunction=...mp;ItemID=11660 will help with the motor getting hot. 17mm hexes will be for Maxx/Savage/1.8 buggy sized wheels. If you really are going to fit that size of wheel, the look on RC4WD's site, they have conversion hexes available. Share this post Link to post Share on other sites
bofin 0 Posted March 19, 2009 well thanks for all the advice ive geared down the car and put mad bull wheels on it it runs fine and is a lot better to use where i live. manta ray Share this post Link to post Share on other sites