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Old 12-19-2014, 04:35 AM
  #16  
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If the temp of the motor is less than 70c, then I'd increase the rollout (decrease fdr).

Some of the Sydney boys run between 2.9 and 2.7 fdr without any overheating and quite good speed.
The motor isn't a rev motor so it can handle a tall rollout. Max motor timing is a must.
Just watch temps.
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Old 12-19-2014, 02:07 PM
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I've gone as low as 2.88 on my Trackstar 21.5 and it didn't get above 120 F. It really likes a low FDR.
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Old 12-19-2014, 06:54 PM
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Originally Posted by nitro_cortex
Generally the trackstar's are okay - they aren't the best but have some pace and with good enough driving, could possibly keep up with more expensive motors. I would say aim for lap times rather than top speed. Some people gear the shit out of their cars but their infield speed suffers greatly.

Play around with the gearing a bit more and try to run your motor between 60-70 deg celcius. Any hotter and it won't be good for the motor, any cooler and you won't be maximising your performance. With regard to spurs, maybe use some aftermarket ones? I'm not familiar with Sakura but I'm assuming they are just standard spurs? (So that you can use RW Racing spurs, etc)
ALL GOOD STUFF HERE..also make sure your drive train is nice and free..i.e..belts, bearings etc free.
we run right down to 2.8/2.9 blinky 21.5 but make sure temps are in check.
Trackstar/turnigy motors as good as anything more expensive so could be a bad one so would pay to try another one to eliminate.
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Old 12-19-2014, 09:15 PM
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Something to consider.... cornerspeed. If you don't have a setup that allows for proper corner speed, it will appear that the other cars are faster. Many times this is incorrectly attributed to a slow motor.
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Old 12-21-2014, 03:45 AM
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Coopz what lap times where you getting Friday night?

at what part of the straight can you hear your motor max its rpm ?
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Old 12-21-2014, 03:27 PM
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Originally Posted by B16A2
Coopz what lap times where you getting Friday night?

at what part of the straight can you hear your motor max its rpm ?
I didn't race Friday, but I was there for a hour before doing practise laps, best was only a 17.8, partly attributed to some handling issues I inflicted on myself and I wasn't running any tyre compound. The motor seemed to peak halfway down the straight and the other 21.5 cars were easily outpacing it.
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Old 12-21-2014, 03:38 PM
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Your problem could well be your motor however the straight is only about 2 seconds of the lap time so it is important to get the rest of the track right.

You will want to get you car handling well for the midsection and the fast sweepers. If your ever at the track and see Billy there go talk to him about Sakura S Zero setups, he was quite quick when he ran that car and had found a setup that suited that track.

As for top speed down the straight gearing will be the key. When do you plan to go there again ?
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Old 12-22-2014, 10:07 AM
  #23  
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Originally Posted by big al
Something to consider.... cornerspeed. If you don't have a setup that allows for proper corner speed, it will appear that the other cars are faster. Many times this is incorrectly attributed to a slow motor.
Boy I heard that a lot with my MBA (much bitched about) Boss motor. But you have to have speed to carry into a turn. Sometimes it is the motor. After replacing the sensor board, finding the timing label was wrong (instead of 45 degrees timing it was actually 58), I got the motor working fine and the same setup was very competitive.
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Old 12-22-2014, 11:44 AM
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Originally Posted by John Wallace2
Boy I heard that a lot with my MBA (much bitched about) Boss motor. But you have to have speed to carry into a turn. Sometimes it is the motor. After replacing the sensor board, finding the timing label was wrong (instead of 45 degrees timing it was actually 58), I got the motor working fine and the same setup was very competitive.
sounds kinda like my motor. but my timing was at 49 instead of 45 according to gforce motor checker. still running it there it works well.
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Old 12-22-2014, 12:11 PM
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Originally Posted by dragonracing
sounds kinda like my motor. but my timing was at 49 instead of 45 according to gforce motor checker. still running it there it works well.
One other thing that helped, I found after I got my motor working well on the straights when I bought a new radio. My old TX/RX I had used on my off road truck and it still had a lot of expo on the throttle. I went to a linear throttle response and the acceleration out of the turns improved too. DAAAAH
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Old 12-22-2014, 12:13 PM
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yeah expo is fine for offroad where traction is low. but for onroad i allway run linear. i used to have some expo but i have gone away from it. when were you coming up this way? to the seattle area?
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Old 12-22-2014, 12:23 PM
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Originally Posted by dragonracing
yeah expo is fine for offroad where traction is low. but for onroad i allway run linear. i used to have some expo but i have gone away from it. when were you coming up this way? to the seattle area?
Some time after the rain stops hahaha. Don't know maybe this Summer.
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Old 12-22-2014, 12:29 PM
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Originally Posted by John Wallace2
Some time after the rain stops hahaha. Don't know maybe this Summer.
hey now...it dont rain all the time...oh wait. it does. lol. currently not raining. imagine that. lol. summer would be good. we have quite a few tracks running in the summer. let me know when your coming up and ill get you the schedule for who what where and when. you know why. lol.
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Old 12-23-2014, 05:02 AM
  #29  
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Just for info, I run a Trackstar 21.5 (ROAR approved edition) with FDR's between 3.55 and 3.35 on a 90 x 40 carpet track. The class is USGT and the car is fast. Motor temps haven't exceeded 130 and I am using a fan.
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Old 12-23-2014, 01:31 PM
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Originally Posted by old_dude
Just for info, I run a Trackstar 21.5 (ROAR approved edition) with FDR's between 3.55 and 3.35 on a 90 x 40 carpet track. The class is USGT and the car is fast. Motor temps haven't exceeded 130 and I am using a fan.
Really depends on the track size. Some of our track layouts the straights are nearly 2X the length of your track with rather flowing turns and people are running ~3.0 FDR with the Trackstar. Probably could have gone higher but it was well over 100F that day and motors were over heating badly. (my esc said my motor was over 240F not quite that hot on the outside)

PS the motor may not be the ROAR spec version since they appear to be from down under.
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