977e
11-13-2014, 03:59 AM
#61
Hi i am looking at getting one of this cars, im used to running 6s on my gt....i ripped a lrp rotor to shreds....
so i doubt i would be doing 6s anytime soon....so my initial setup would be 4s....lets say i use a 2400kv up....what gearing would i use? i saw someone gave some great advice saying that he used 16-18t.....but what would happen if i went higher? excessive heat or heavy lipo drainage? i need a fast car to get my thrills. but ive blown a few motors and its pretty pricey....If i do this i want to buy what i need one time and cry n a corner with buyers remorse later....
So what would my shopping cart be?
977e,
wheels,
body,
viper esc and 2700kv combo,
gearing/ 16-18t?
and what else??
a spare set of belts?
Im in SA so importing stuff takes a while so i dont want to get stuck...
so i doubt i would be doing 6s anytime soon....so my initial setup would be 4s....lets say i use a 2400kv up....what gearing would i use? i saw someone gave some great advice saying that he used 16-18t.....but what would happen if i went higher? excessive heat or heavy lipo drainage? i need a fast car to get my thrills. but ive blown a few motors and its pretty pricey....If i do this i want to buy what i need one time and cry n a corner with buyers remorse later....
So what would my shopping cart be?
977e,
wheels,
body,
viper esc and 2700kv combo,
gearing/ 16-18t?
and what else??
a spare set of belts?
Im in SA so importing stuff takes a while so i dont want to get stuck...
The Tekin 1900kv motor I used in my 966e, has around 100 runs on it, without any problem! (I didn't even ever took the motor apart)
But it's up to you.
11-13-2014, 04:00 AM
#62
11-13-2014, 05:12 AM
#63
Reedy Wolfpack serie 
11-13-2014, 05:30 AM
#64
Thanks!
11-13-2014, 06:01 AM
#65
Tech Adept
Im by no means scared of 6s i love driving fast cars but for my initial setup would add another R2000 on a R12000 setup......which is alot....so i have quite a few high quality 2s packs i can use. I will eventually get me a 6s setup which would just be a other motor and the two 3s packs.....but that i can do after a while.....Im also curious to see just how fast the car will go on 4s....as always its not the top speed but how it gets there.....with my GT i tend to top out way to early on 4s but 6s is perfect....i love how the front wheels lift off the ground lol
11-13-2014, 06:21 PM
#66
Tech Regular
ok, if you have 2s packs already... makes sense then.
best to get a range of pinions 17-19t to find what works best for you.
at least 2400kv motor is good.
bigger pinion increases current and therefore heat and it gets to a point where it too much for some of your components usually the battery. beyond a certain point it doesnt increase speed anymore and simply makes more heat which is totally inefficient. so we tend to start with smaller pinion obviously and incrementally work up.
best to get a range of pinions 17-19t to find what works best for you.
at least 2400kv motor is good.
bigger pinion increases current and therefore heat and it gets to a point where it too much for some of your components usually the battery. beyond a certain point it doesnt increase speed anymore and simply makes more heat which is totally inefficient. so we tend to start with smaller pinion obviously and incrementally work up.
11-14-2014, 01:26 AM
#67
Tech Adept
thanks bud that is all i needed to hear....would you guys stick with sensored? or do you feel like that wont matter if you use sensorless on such a large scale car?
im looking at a range of high kv motors....but what im concerned about is temps....will high kv motors like a 2650/2700kv be higher risk even if geared lower or would a 2400kv work wonders on 16t-18t?
i kinda popped a lipo last night using a 3000kv motor and 25/46 gearing on my kyosho gt...the lipo felt hot and lost some of its insides lol...i think i over geared so it created a high draw.
im looking at a range of high kv motors....but what im concerned about is temps....will high kv motors like a 2650/2700kv be higher risk even if geared lower or would a 2400kv work wonders on 16t-18t?
i kinda popped a lipo last night using a 3000kv motor and 25/46 gearing on my kyosho gt...the lipo felt hot and lost some of its insides lol...i think i over geared so it created a high draw.
11-14-2014, 09:27 AM
#68
Tech Regular
I think the 977 will be lighter than a GT so less problems...but im not familiar with the gearing on those.
My car is sensorless right now and not as good as sensored when it comes to race starts..otherwise no different. The turnigy esc i have does a great job of starting it though (of the esc's ive had).
Higher kv motor wont be a problem if you start with smaller pinion and check things before changing pinion. maybe 16t to begin with....check the calculator
I made a excel calculator much like the serpent 977e gearing calc a couple of years ago and I have found that aiming for about 105km/h with 75mm rear tyre to be pretty spot on to start with gearing for 4S (seems like i can go much higher with 6S now).... and this may be a personal preference but i like to see at least 3.5v per cell left in the battery after a race....i would like my battery to last a year at least.
My car is sensorless right now and not as good as sensored when it comes to race starts..otherwise no different. The turnigy esc i have does a great job of starting it though (of the esc's ive had).
Higher kv motor wont be a problem if you start with smaller pinion and check things before changing pinion. maybe 16t to begin with....check the calculator
I made a excel calculator much like the serpent 977e gearing calc a couple of years ago and I have found that aiming for about 105km/h with 75mm rear tyre to be pretty spot on to start with gearing for 4S (seems like i can go much higher with 6S now).... and this may be a personal preference but i like to see at least 3.5v per cell left in the battery after a race....i would like my battery to last a year at least.
11-17-2014, 10:24 AM
#69
Tech Apprentice
Is there a list of manufacturers of 3S batteries that fit this car at all?
11-20-2014, 06:19 PM
#70
Tech Regular
normal sized 3S (like the many 2S hardcase lipo size) i havent seen many to choose from at the moment. reedy, LRP or trinity have them that im aware of.
If you can use soft/caseless lipo then you have cheaper option of using the turnigy nanotech (traxxas replacement battery) I got the 4000mah 40c ones, and the fit well but I put some cloth tape on the top and bottom to protect the shrink wrap from tearing.
If you can use soft/caseless lipo then you have cheaper option of using the turnigy nanotech (traxxas replacement battery) I got the 4000mah 40c ones, and the fit well but I put some cloth tape on the top and bottom to protect the shrink wrap from tearing.
11-22-2014, 11:20 AM
#71
Tech Apprentice
Thanks Jeff. Have found and bought some of the LRP ones. Look forward to receiving them and taking the car to a track.
11-22-2014, 12:17 PM
#72
Tech Apprentice
Hi guys,
Yesterday finally I managed to run my 977e for the first time.
I did test the prototype, some time ago, but now I have the kit version, which has a few improvements, over the prototype, (nothing related to performance
)
For the first time I drove 21 laps in 5.14, which is a record for me, on our track.
After all testing I have done the last year or so with the Tekin stuff I run, I did make a usefull "roll-out chart" for eveybody to use, to give a good starting point for gearing compared to rear tyre diameter.
You can find it on Serpents website in the download section of the 977e.
http://serpent.com/product/904002/downloads/
http://serpent.com/file.php?FileID=6053
The sheet works really simple.
If you run the T8 2050kv motor, you want the car geared between 41-42mm, on a nice open 8th scale track.
On smaller tracks, go down 1 or 2 mm.
For this example, lets take 41mm roll-out.
Start with measuring the tire diameter of your rear tires.
Lets take 73mm for example.
Now check under the 73mm tire diameter, which spur/pinion combination gets closest to 41mm, and put that in your car.
In this case you will end up with 49/15.
If you don't really constantly want to exchange the spur (I don't!) just start running your car with new tires of around 77mm, with the gearing 48/14 then, and once the tires wear down to 72mm, gear up the car to 48/15.
that's it!
Yesterday finally I managed to run my 977e for the first time.
I did test the prototype, some time ago, but now I have the kit version, which has a few improvements, over the prototype, (nothing related to performance
)For the first time I drove 21 laps in 5.14, which is a record for me, on our track.
After all testing I have done the last year or so with the Tekin stuff I run, I did make a usefull "roll-out chart" for eveybody to use, to give a good starting point for gearing compared to rear tyre diameter.
You can find it on Serpents website in the download section of the 977e.
http://serpent.com/product/904002/downloads/
http://serpent.com/file.php?FileID=6053
The sheet works really simple.
If you run the T8 2050kv motor, you want the car geared between 41-42mm, on a nice open 8th scale track.
On smaller tracks, go down 1 or 2 mm.
For this example, lets take 41mm roll-out.
Start with measuring the tire diameter of your rear tires.
Lets take 73mm for example.
Now check under the 73mm tire diameter, which spur/pinion combination gets closest to 41mm, and put that in your car.
In this case you will end up with 49/15.
If you don't really constantly want to exchange the spur (I don't!) just start running your car with new tires of around 77mm, with the gearing 48/14 then, and once the tires wear down to 72mm, gear up the car to 48/15.
that's it!
Couldn't see the top speed on Mylaps practice though
14,6 fastest laptime is also pretty fast.
Anybody interested in a 966E
See you on the track.
11-25-2014, 09:19 AM
#73
dont be afraid of 6S. it doesnt have to mean faster, more volts just means less amps which is cooler and therefore efficient and capable to deliver more power.
so if you are considering 4S with 2400kv you might get more run time and cooler temps with similar power running 6S and 1600kv. both would use the same gearing. id select 19t to start with.. for my track with me driving.. but you might want to check the 977e calculator.
im using 1800kv speed passion motor on turnigy 150a esc with 17t pin and 6S...its great.
BTW the transponder is stuck to underside of servo.
so if you are considering 4S with 2400kv you might get more run time and cooler temps with similar power running 6S and 1600kv. both would use the same gearing. id select 19t to start with.. for my track with me driving.. but you might want to check the 977e calculator.
im using 1800kv speed passion motor on turnigy 150a esc with 17t pin and 6S...its great.
BTW the transponder is stuck to underside of servo.
got mine running and Oh boy this thing moves even the gas guys in the club noticed it .. Im running 4s 2250kv im getting 7 min on my 7200mah R1 battery i was under geared I started with the stock pinion it was so quick but had to gear up for top end Im now using 16T pinion
Last edited by BIBOY; 11-25-2014 at 09:30 AM.
11-25-2014, 06:23 PM
#74
Tech Regular
the trackstar is great its a little jumpy at really low speed like the minimun throttle is a bit high. Also it starts sensorless motor from standing start really well.
i havent used "turbo" much I have about 5 degress in it but i dont think its going to benefit a 4pole 12slot motor very much. dont really need more top speed anyway!
i havent used "turbo" much I have about 5 degress in it but i dont think its going to benefit a 4pole 12slot motor very much. dont really need more top speed anyway!
11-25-2014, 07:04 PM
#75
This car may be a game changer. First, serpent quality is unreal. Second, a lot of guys don't want to hassle of nitro motors.
How heavy is this car rtr? What is the run time for a pretty large track? The only thing that I would personally be afraid of is smacking a board at a fairly high speed with this missile..that might be very expensive...
How heavy is this car rtr? What is the run time for a pretty large track? The only thing that I would personally be afraid of is smacking a board at a fairly high speed with this missile..that might be very expensive...
Last edited by SouthFloridaApp; 11-25-2014 at 07:30 PM.