I got a well used HPI octane recently (looks abused: some poles on rolling cage broken, well tear/wear base plastic plates, cracked muffler, etc).
In my 1st drive (1st~2nd tanks of gas), I didn't notice servo twitching issue.
In my 2nd drive (2nd day, 3rd~4th tanks of gas), in 3th tank gas, I saw the throttle servo and front wheels are vibrating slightly from engine start up. In 4th tank gas, the car can hardly turn right but easier to turn left gradually, the gas throttle servo just vibrate by it self and out of control. I thought it was battery issue and recharged the batteries, but the two 1600mah batteries ate only 800mah to 1000mah (formerly charged 1000mah~1200mah, so I suppose the batteries are not totally drain).
The same day, I connected one charged 1600mah NiMH battery to receiver, and connected a charged 7.4v LiPo battery to CDI (I recall later that I connected this battery in reversed pole), started up (yes! it did start up even through the CDI power supplied is twisted!), the two servos vibrate seriously. While the engine kept running, I moved CDI away from the battery box, the servo vibration stopped. But soon the steering servo dead. Dissembled the servo, found one small chip closed to motor cable(3 pins, stated AHR or BHR, don't remember) has burning mark.
Bought two new steering servos.
In my 3rd drive (5th tank of gas), I installed one steering servo, connected two 1600mah NiMH (all placed in battery box), move CDI right behind the real body poles, tested and both servos responded well, either on/off engine. No twitching. Try to move CDI closed to battery box, saw some random slight twitching on gas servo.
In my 4th drive (6th tank of gas), I replaced 1600mah NiMH battery for CDI with a 7.4v 1000mah LiPo, so far so good.
Remained problems (have these problems from my day1 in HPI octane):
1, Difficult to start engine esp. for hot engine. For cold engine, normally 1~8 pull can start the engine. For Hot engine, even 20~30 pulls are useless. Have to wait more than 5 mins, then pull again, then it can start within 10 pulls.
2, Looks like the engine is not quite powerful. It does accelerate with full throttle, but so far didn't observed front wheels head-up. But from the tear/wear mark on rolling cage, the former owner must flip-flop the car quite many times.
3,I heard gear switch from Gear1 to Gear2, but didn't find out Gear2 jumping to Gear3. Maybe because my ears not sensitive enough.
4,When the gas tank almost empty, the car will accelerate by it self. Is it normal?
In my 1st drive (1st~2nd tanks of gas), I didn't notice servo twitching issue.
In my 2nd drive (2nd day, 3rd~4th tanks of gas), in 3th tank gas, I saw the throttle servo and front wheels are vibrating slightly from engine start up. In 4th tank gas, the car can hardly turn right but easier to turn left gradually, the gas throttle servo just vibrate by it self and out of control. I thought it was battery issue and recharged the batteries, but the two 1600mah batteries ate only 800mah to 1000mah (formerly charged 1000mah~1200mah, so I suppose the batteries are not totally drain).
The same day, I connected one charged 1600mah NiMH battery to receiver, and connected a charged 7.4v LiPo battery to CDI (I recall later that I connected this battery in reversed pole), started up (yes! it did start up even through the CDI power supplied is twisted!), the two servos vibrate seriously. While the engine kept running, I moved CDI away from the battery box, the servo vibration stopped. But soon the steering servo dead. Dissembled the servo, found one small chip closed to motor cable(3 pins, stated AHR or BHR, don't remember) has burning mark.
Bought two new steering servos.
In my 3rd drive (5th tank of gas), I installed one steering servo, connected two 1600mah NiMH (all placed in battery box), move CDI right behind the real body poles, tested and both servos responded well, either on/off engine. No twitching. Try to move CDI closed to battery box, saw some random slight twitching on gas servo.
In my 4th drive (6th tank of gas), I replaced 1600mah NiMH battery for CDI with a 7.4v 1000mah LiPo, so far so good.
Remained problems (have these problems from my day1 in HPI octane):
1, Difficult to start engine esp. for hot engine. For cold engine, normally 1~8 pull can start the engine. For Hot engine, even 20~30 pulls are useless. Have to wait more than 5 mins, then pull again, then it can start within 10 pulls.
2, Looks like the engine is not quite powerful. It does accelerate with full throttle, but so far didn't observed front wheels head-up. But from the tear/wear mark on rolling cage, the former owner must flip-flop the car quite many times.
3,I heard gear switch from Gear1 to Gear2, but didn't find out Gear2 jumping to Gear3. Maybe because my ears not sensitive enough.
4,When the gas tank almost empty, the car will accelerate by it self. Is it normal?
