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02.01.2007, 02:24 AM

glassdoctor,

I really can't put into words the amount of help you have been. My ignorance is driving me crazy. I am not new to brushless. I was the first one out at my track with a brushless setup. I had to do some fast talking so that they'd let me run it, but they did and now I'm doing more talking about running my 1/8 scale buggy. Some guys looked interested and others looked worried. LOL. 10th scale was easy. All I could fit into the truck and still have it behave right was either 2S Lipo or a six cell pack. Now that the battery options have opened up, things have gotten really complicated.

How fast do I want to go? 200 mph. What would I settle for? I'd love to do 60, just to see the faces on the Jato guys. I could probably live with 50. I wouldn't win too many races, but it would put on a good show. Besides, my T4 is what I have for 60+. Although I did just crash it AGAIN. Darned right rear wheel peeled off and flipped the truck. Skidded forever until a post stopped it for me. Took off the whole left side. That mamba 7700 on 3S is wicked.

Anyway, I'm thinking that going with the 1515/1Y is going to be it. That should be perfect for my track. Besides, I found some specs on the Neu motors and it looks like the 1515 is a bit more efficient than the 1512 and unless I read something wrong, the 1515 1Y pulls fewer amps than the 1512 2600kv motor.

At this point, and I'm going back and forth in my mind, it's between the 1512 2d (2600 kv for ~38,000 @ 14.8v) or the 1515 1Y (2200 kv for ~32,000 @14.8v). If I think about it (and it hurts), it is with the realm of possibility that the 1512 will be undergeared for the track and will run hot. On the other hand, I could probably gear up the 1515 to be just as fast as the 1512. If the ESC overheats it will thermal and protect itself. I guess the big question is (or is it?) where do I want to be topping out? 38K or 32K rpms. Either way, the motor is going to be turning far fewer than the 60,000 rpm limit as published by Neu and both will be within the efficiency range. Which is better, the bottom of the efficiency range or the top? And...on another note, I have to assume that the 1515 will have a bit more torque than the 1512, but do I need it with a buggy that will never hit over 9 lbs even sopping wet with mud?

BTW, with regard to your last post. When I first started toying with the idea of an electric buggy, I was trying to find a motor/battery combination that would mimic the performance/operation of a nitro setup. I wanted a motor that turned 40,000 rpm with a 13T or 14T pinion on it.

The guys at my track run engines that are "rated" as turning ~40,000 rpm when tuned to peak performance. They are the guys I want to outrun. Ya see, once again, when I put it into those terms, that 1512 2d is looking mighty good. I just don't want to be running a 10T pinion, spacing might become a problem.

	(#5)
AAngel Guest Posts: n/a	02.01.2007, 02:24 AM glassdoctor, I really can't put into words the amount of help you have been. My ignorance is driving me crazy. I am not new to brushless. I was the first one out at my track with a brushless setup. I had to do some fast talking so that they'd let me run it, but they did and now I'm doing more talking about running my 1/8 scale buggy. Some guys looked interested and others looked worried. LOL. 10th scale was easy. All I could fit into the truck and still have it behave right was either 2S Lipo or a six cell pack. Now that the battery options have opened up, things have gotten really complicated. How fast do I want to go? 200 mph. What would I settle for? I'd love to do 60, just to see the faces on the Jato guys. I could probably live with 50. I wouldn't win too many races, but it would put on a good show. Besides, my T4 is what I have for 60+. Although I did just crash it AGAIN. Darned right rear wheel peeled off and flipped the truck. Skidded forever until a post stopped it for me. Took off the whole left side. That mamba 7700 on 3S is wicked. Anyway, I'm thinking that going with the 1515/1Y is going to be it. That should be perfect for my track. Besides, I found some specs on the Neu motors and it looks like the 1515 is a bit more efficient than the 1512 and unless I read something wrong, the 1515 1Y pulls fewer amps than the 1512 2600kv motor. At this point, and I'm going back and forth in my mind, it's between the 1512 2d (2600 kv for ~38,000 @ 14.8v) or the 1515 1Y (2200 kv for ~32,000 @14.8v). If I think about it (and it hurts), it is with the realm of possibility that the 1512 will be undergeared for the track and will run hot. On the other hand, I could probably gear up the 1515 to be just as fast as the 1512. If the ESC overheats it will thermal and protect itself. I guess the big question is (or is it?) where do I want to be topping out? 38K or 32K rpms. Either way, the motor is going to be turning far fewer than the 60,000 rpm limit as published by Neu and both will be within the efficiency range. Which is better, the bottom of the efficiency range or the top? And...on another note, I have to assume that the 1515 will have a bit more torque than the 1512, but do I need it with a buggy that will never hit over 9 lbs even sopping wet with mud? BTW, with regard to your last post. When I first started toying with the idea of an electric buggy, I was trying to find a motor/battery combination that would mimic the performance/operation of a nitro setup. I wanted a motor that turned 40,000 rpm with a 13T or 14T pinion on it. The guys at my track run engines that are "rated" as turning ~40,000 rpm when tuned to peak performance. They are the guys I want to outrun. Ya see, once again, when I put it into those terms, that 1512 2d is looking mighty good. I just don't want to be running a 10T pinion, spacing might become a problem.