started with 84 17....tried 84 18

I run 17/86 with an 8.5 in my TS2. Same internal gear ratio as SC10.

I an give it a try lol...the real prob is I didn't change anything from last week and the temps were fine...thinkin esc issue....motor is new couple weeks old

7.5t? I swear you told me you were running 8.5t...my bad to the previous poster...go with the 7.5t. That said it will depend on the track, it isn't all about ultimate speed at most.

yeah 7.5 in sc2wd and 8.5 in b4.1 buggy....Tyler ran it tonight 4 times and it temped out in like 630 to 7 min everytime and we tried a lot of different things

My vtx8's have been great in my hb / tekno ebuggy and etruggy. I am running a 2050 in the d812 on a tekno v4 chassis geared 19/48 (light weight d812 spur and in the d8t on a tekno v4 chassis geared 15/48 on a 2150 (on a light weight hara spur).

Ok so what are the ramifications of having too much motor? I mean I ran the 10.5 in my XXX-SCT in the above posted video and I'm pretty sure it was top end speed that is the reason I didn't win. Would a higher turn motor build less heat if geared properly?

For those that haven't figured it out weyant (and his son) and I run at the same track, he and his son are both in the video I posted in the green and pink trucks. So the track where he runs in the track in the video.

that's why I went with the 7.5 he ran a 9.5 before and got to hot all the time with the 7.5 it was great 100 on motor until this weekend. we don't run stock spec classes so thought why not get bigger and turn it down so that if we need the power we got it

Weyant - if you are seeing an external temp of 160-170 you will need your VTX motor cut off settings at 230-240. Internal temperature on the rotor can be 50-60 degrees higher than what is read on the outside. Throw into the fact that as we get into the summer the outside temp is higher as well. Typically with a mod motor higher freq will help cool the motor, as will lower punch. If you are diligent to watch your temps with a temp gun you can disable the setting if you like.

Grasshopper - in theory, running a motor that is faster, you will not be on "full" power as long, so the temp would be less. More time you spend at full throttle, more heat you are going to generate. Then you have to be careful, but you have lot more power to control.

meh, I was talking to a fast guy about why I was having trouble clearing a few jumps and such. I was boosting and gearing and doing everything I could to try and gain more power. He looked at my car and said I was getting too much wheel spin. All the power I was creating was only wearing out my tires. He gave me a few tips and explained that my tires were worn out as well. By my standards the tires were fine, only 6 weeks old. I asked him how long he ran them before swapping out. He said 1-1 1/5 weeks, then they were practice tires. Then he showed me a set of his practice tires that were better than my race tires, lol. More often then not, us weekend warrior racers are running on "bad" rubber. I changed out my lightly worn rear tires for some new ones and the car felt immediately better. That being said, i cant afford new tires every 2 weeks, lol, so I will just get good a driving a little loose and roll the throttle better to make my tires last longer. If you run a motor that is past your driving skill, you will probably just wear out your tires and car faster. For me that is a 10.5. Anything more than a 10.5 and i am just making my life harder. And the lower the bite the track, your just going to make it worse. Most of the people on these forums seem to post based on high bite grooved tracks. I sometimes run on those, but for the most part I run on a low bite outdoor 8th scale track and I would never run a 7.5 because I would just have more dnf's to a broken car and I would just wear out everything faster. I like the 10.5 for those reasons. The pros run 7.5's, I am no pro, lol. I run what I can drive around the track.

Wheel spin = motor heat
Lower throttle freq = motor heat + wheel spin
Seems like that might be what your problem is. I ran my 2wd SC10 yesterday in the main at our local track. Its got an 8.5 and it was pretty warm out. Came off the track at 146. I almost always run higher throttle freq.

Right now I'm running a VTX10R and a VST 7.5 in my SC10.2 FT with 18 / 84 gearing on a large outdoor track, very happy with it so far, very smooth power, doesn't get too hot either.

I previously ran Novak exclusively, but I'm so happy with Viper that I ordered a VTX10 / VST 17.5 for my wife's SC10.

I raised the throttle Freq.....we'll see what happens. as far as wheel spin I thought that too but tried other tires and a really good driver at our track ran it and he said it felt great to him right up until it shut off lol....kinda worried its an ESC prob. 18 -81 that sounds alittle HOT to me. shouldn't a 84 spur help keep the temps down compared to a 81??

No heat problems with my setup as of yet and it's pretty hot here in FL, but I actually have a 84 spur, thought it was 81 for some strange reason.