2Likes3Racing Sakura Zero S
03-06-2013, 05:32 PM
#2536
Interesting. Good info.
03-06-2013, 05:54 PM
#2537
Tech Adept
Question...i just switched to a lower turn/higher kv motor (xerun 3.5t 120a combo) from the castle sv2 4 pole 6900kv combo...i used the same gearing same battery and i couldn't to the speed i had with the castle system.someone suggested my gears were to aggressive for the 3.5 and i need to gear down for the motor to Reach full rpm....i am going to try that but i wanted a second opinion.its there any truth to that? The gearing i am running is 73t spur and36 pinion.
03-06-2013, 06:06 PM
#2538
Question...i just switched to a lower turn/higher kv motor (xerun 3.5t 120a combo) from the castle sv2 4 pole 6900kv combo...i used the same gearing same battery and i couldn't to the speed i had with the castle system.someone suggested my gears were to aggressive for the 3.5 and i need to gear down for the motor to Reach full rpm....i am going to try that but i wanted a second opinion.its there any truth to that? The gearing i am running is 73t spur and36 pinion.
With the Ezrun at 9100kv with same gearing and voltage you should be hitting 114.3mph. If you are not, could be that the EZ is not really the same type of motor. Firstly it's not a 4 pole motor, I believe it's only 2 ( I could be wrong) and also that the diameter is not the same equivalent as the Castle. A 3650 is not the same as a 540 which is what a Castle is. With a smaller diameter it wont have the same torque under load and will struggle and you will not get the same speed as the motor wont be able to reach it's top end speed. You basically put a higher KV motor that is a smaller diameter with less torque in the same car with the same weight and anticipate the same performance and speed as a larger 4 pole motor.
Hope that helps.
Last edited by Speed Passion; 03-06-2013 at 06:32 PM.
03-06-2013, 06:33 PM
#2539
Tech Adept
If you can give me the following I can tell you almost exactly your speed and rollout:
Need:
Voltage: 7.2; 11.1
Total Trans ratio:
Tier Diameter in mm:
Kv on the 3.5T motor:
I can tell you quite a bit.
From the small amount of info you have with the Castle, you seem geared high even at 7.2v with the Castle. You must have been doing high speed runs. With 62mm tire diameter and 6900kv with the gearing you mentioned your rollout: 1.992inch motor rev and speeds are at: 86.6mph. Sound right?
Hope that helps.
Need:
Voltage: 7.2; 11.1
Total Trans ratio:
Tier Diameter in mm:
Kv on the 3.5T motor:
I can tell you quite a bit.
From the small amount of info you have with the Castle, you seem geared high even at 7.2v with the Castle. You must have been doing high speed runs. With 62mm tire diameter and 6900kv with the gearing you mentioned your rollout: 1.992inch motor rev and speeds are at: 86.6mph. Sound right?
Hope that helps.
using the sakura zero s internal stock gears
tier diameter? same as stock
9100kv on the 3.5
and my top speed with the castle was 69mph according to gps and yes speed runs..
sorry for lack of detailed info im a newbie
its the xerun not ezrun w the fins. the motors are virtually the same sizeaout 1-3mm in length difference. the only three differences i know for certain between the two are one is 4pole, sensorless, and 6900kv(castle)
whie the other is 2pole, sensored, and 9100kv
Last edited by sonspit; 03-06-2013 at 06:44 PM.
03-06-2013, 07:02 PM
#2540
7.2v 2s 3800mah 35c
using the sakura zero s internal stock gears
tier diameter? same as stock
9100kv on the 3.5
and my top speed with the castle was 69mph according to gps and yes speed runs..
sorry for lack of detailed info im a newbie
its the xerun not ezrun w the fins. the motors are virtually the same sizeaout 1-3mm in length difference. the only three differences i know for certain between the two are one is 4pole, sensorless, and 6900kv(castle)
whie the other is 2pole, sensored, and 9100kv
using the sakura zero s internal stock gears
tier diameter? same as stock
9100kv on the 3.5
and my top speed with the castle was 69mph according to gps and yes speed runs..
sorry for lack of detailed info im a newbie
its the xerun not ezrun w the fins. the motors are virtually the same sizeaout 1-3mm in length difference. the only three differences i know for certain between the two are one is 4pole, sensorless, and 6900kv(castle)
whie the other is 2pole, sensored, and 9100kv
Hope that helps.
Last edited by Speed Passion; 03-06-2013 at 07:15 PM.
03-07-2013, 04:35 AM
#2541
Tech Adept
The poles will make a difference. You are losing torque switching to a higher KV motor. Also, check your ESC settings as it's new also. On the ESC be sure that nothing is set to limit the motor and that the timing is at it's factory default settings like "Punch" on the Castle for example. Also that it's set to the correct voltage unless it's auto but if the battery is not fully charged or it's not detecting all the cells it may not run at the correct voltage. Also check the low voltage cut off settings are correct. All things being the same, your speed should theoretically be 88.0mph with 9100kv. I see where my last statement was over rated. I had the voltage set high. Once I corrected that I get about 69mph.
Hope that helps.
Hope that helps.
But is there any truth to what i was told about the gearing? Is it possible that the pinion is to big for the higher kv and is not allowing it to reach its top rpm
03-07-2013, 05:51 AM
#2542
Tech Adept
i see there are 2 versions of the vertical motor mount... can i use version 2 on my zero s? i ordered it mistakenly.
03-07-2013, 10:03 AM
#2543
Hope that helps.
03-07-2013, 01:03 PM
#2544
Tech Adept
Yes you can use either one. Version 3Racing (SAK-S17/PK) will have the full aluminum 3 pieces (not what you ordered), which is the motor mount and two gear pulley holders that are aluminum, and the other version Version 2, will only have two pieces that is the motor mount and one aluminum pulley holder and you have to use the plastic one that came with the kit-kinda cheesy. I also thought a Version 2 is a better version right? You want the 3 piece version (SAK-S17/PK) as it's better support for the pulley shaft. Maybe you can return it and get the 3 piece one?
Hope that helps.
Hope that helps.
03-07-2013, 02:11 PM
#2545
03-08-2013, 09:15 AM
#2546
Tech Regular
As a general rule, the higher the Kv rating (and lower number of turns), the smaller your pinion gear should be (higher final drive ratio). I race with a 4.5 turn geared at around 8.3 FDR, you're geared at less than half of that (4.05 FDR if you've changed to the 19T pulleys). Your 35C battery could also be limiting you. In fact, I'm surprised it hasn't "puffed", because you seem waaaay over-geared to me.
03-08-2013, 10:41 AM
#2547
Somewhat yes, with higher torque motors you can gear higher than lower torque motors and not lose any speed. As long as the motor is not over heating you should be fine.
03-08-2013, 10:47 AM
#2548
Wanted to share this with everyone. While building the Zero, I was not crazy about all the battery mounts that were needed to hold in the battery, and also when having to flip the drive over to the other side in using the vertical motor mount also.
What I did was the following which was easier and a lighter battery system to where you can still use the factory strap and it fits perfectly and looks clean.
Get these:Associated Factory Team Carbon Servo Mounts TC4 (you need two sets making 4 of these servo holders in total)
Solution: Take each one, with the small tab that sticks out that will be the bottom for each holder. That will be the side that mounts flat onto the chassis. The little tabs actually align with the holes on the chassis but you have to file the diameter slightly smaller, takes one minute to do each one.
The hole that is now on the inside, take a 3mm drill and hand bore out each hole. You need to do this on all four. One one side, take the metal battery bar, slide the battery strap onto it on one side and mount onto chassis. Repeat on other side. The only stock battery holder you want to use with this setup is the one that looks like a flattened long "U" called battery mount "C" in the manual. That one you would place in the factory location in the center mounting location on the right side (looking from the rear of the car) to keep the battery from flying out.
Now you have a $6.60 battery holder that even with the belts flipped won't be in the way and no major cutting or grinding is needed, looks factory, is clean and lighter and low profile!
Hope that helps!
P.S. TQ RC Racing is out of stock as I bought the last set to do this. Sorry.
What I did was the following which was easier and a lighter battery system to where you can still use the factory strap and it fits perfectly and looks clean.
Get these:Associated Factory Team Carbon Servo Mounts TC4 (you need two sets making 4 of these servo holders in total)
Solution: Take each one, with the small tab that sticks out that will be the bottom for each holder. That will be the side that mounts flat onto the chassis. The little tabs actually align with the holes on the chassis but you have to file the diameter slightly smaller, takes one minute to do each one.
The hole that is now on the inside, take a 3mm drill and hand bore out each hole. You need to do this on all four. One one side, take the metal battery bar, slide the battery strap onto it on one side and mount onto chassis. Repeat on other side. The only stock battery holder you want to use with this setup is the one that looks like a flattened long "U" called battery mount "C" in the manual. That one you would place in the factory location in the center mounting location on the right side (looking from the rear of the car) to keep the battery from flying out.
Now you have a $6.60 battery holder that even with the belts flipped won't be in the way and no major cutting or grinding is needed, looks factory, is clean and lighter and low profile!
Hope that helps!
P.S. TQ RC Racing is out of stock as I bought the last set to do this. Sorry.
03-08-2013, 01:49 PM
#2549
Tech Adept
03-08-2013, 06:18 PM
#2550
