• Thanks for all the responses!!!!!
    Thanks for all the responses. Dont all answer at once or anything!!!!!!
  • We need more info then that to help you mate, where are you running, surface type, any cooling systems, track layout and description? Do you have a temp gun to check the motor temps?

    And isnt likely to get you help mate.
  • Allways Google before you flame
    Have you tried using google? I just did, and here's what I found out. That motor, is designed for offroad use.

    However, I figure a 4wd buggy is probably in the ballpark for an on road tc. (at least its the closest match weight and driveline wise). Now castles website, which you can find in google, actually lists a bunch of example cars with their spur and the pinion range to use as a guide. I picked the first one a B44. So again I turned to google. This gave me the internal ratio of a b44, which turns out to be 2.5. Now castle list 16-18 as the pinion range, so i picked 17, and went to the trusty windows calculator (didnt need to google that one I knew where it was). And long story short, its an fdr of 12.7.

    Now another translation, just to check it out novaks gearing chart (guess how i found that?) says for a 4wd off road buggy and fdr of 11-12 would be about about a 5.5t to 4.5t motor, sounds about right for 5700kv. The same motors in a touring car would be 8.5-9.5. So, I googled how to work out an fdr (I didnt really just wanted to say google, I know how to do this though because i googled and found a friendly forum that had all the answers i needed, and for the questions it didnt i aksed nicely... and didnt use caps, or a ).

    For you to produce an fdr of 9ish you need a... drum roll please... a 19t pinion. Which will be 9.16. But you'll need to keep a close eye on temps, and go lower in the pinion (or up in the spur) if it gets too hot. You can find temp guides on castles website, google it up and have a look.

    If you dont have a temp gun you can probably find a bunch of places that sell them if you just jump on google...

    Why tell you all this? I wanted to prove how long it took me not only to work it out, but to research it, I started right after I last posted, and proofed this before i submitted.

    Of course, all this goes out the window if your on a 3s and not a 2s.. want to know what that is? GOOGLE IT
  • Bravo !!
  • OK,

    Sorry Gents. I am just frustrated a bit. My original goal was to have a beast of a car and be able to bash on it and drive it hard now matter the motor setup i had. I wanted it to be stupid fast so i chose the 7700KV originally. Now that i have seem to have damaged my 7700KV due to temps. i am dropping down to a 5700kv in hopes i can stabalize my speed and temps. Thus i ask you guys, the experts, and i dont mean that as a snide comment, but the truth.

    So I have a temp gun yes. I run mainly in parking lots but race on carpet once a month at my local track. I run Venom 50C 5000Mah packs. I have the castle creations cooling fan, but have recently removed it due to testing. I have googled all the stuff you mention. Yet I was still having trouble. Intially i was running a 7700KV in the TC5. I got it up over 200 degrees with all the reccomended settings. On the 7700KV i started at a 23t and am currently at a 15t with temps still in the 200 degree range after running for about 10 minutes. Then when i did some more research and called castle directly, they made mention that the 7700KV are really for dragging and are setup for speed and not endurance, thus using it for bashing is a good way to over heat it since it already runs hot. They suggested the 4 pole motor for its cooling power and torque. Thus I pruchased this motor and am hoping the new 5700KV 4 pole is a better all around motor for bashing and racing while keeping temps in check easier.
    I have made the inital mistake of sending the motor over 200 degrees. i dont want to do that again so i am trying to be extra careful this time. The other caveat of my issue is that i live in TN and its really hot here right now, 95 degrees plus. Now i never run in the day, only at night, when its beteween 70-80 degrees. My old HPI flux 2 came with a 5700KV motor and a 23t pinion over a 90t spur. SO i am thinking that the tc5 having an 87t spur that a 18- 19 tooth should do the trick. Lets say i go with an 18t and have an FDR of 9.66. SHould i be able to run several packs through the car and maintain this temperature givein it does lye within spec? Simply put, will a 9.66 ratio maintain temps over sustained usage of several packs. Or is it better to have an even highe ratio so that if i run several packs through the car it will heat up less over time and maintain spec temps?

    Thanks for the help guys, and sorry for getting pissy. Just frustrated.
  • Do you know the internal ratio difference between the flux and the tc5? Your better off to go way higher in the ratio and bring it down. 2 minute run temp the car, if it's high go up a tooth, if it's low go down. But let the motor cool between runs or it will effect the readings your getting. Try and keep your runs consistent each time. Better to do it on a track then just bashing.
  • The FDR with the HPI on the stock 23t pinion would be 8.33. 90 spur and 23pinion with a trasmission of 2.13 vs. the tc5 at 2.0. Currently my HPI is running a FDR of 7.66 with the 25t pinion i have installed.

    Just got all my gears in and mounted the motor with a 17t pinion. That will start my FDR @ 10.23 and will be using this as my starting point. Before I run the tests though, I am going to take your advice and head to the track this weekend.

    I'll post back and let you kow what I find.
  • Finnally,

    SO using a 17t pinion i was able to runn all day in 90 degree heat. Using 2S lipo i never got above 135 degrees on the new motor.
    Now the question is this.
    What is the ideal FDR for this 5700KV 4 pole motor using 3S lipo?
    Right now i am runing a 10.23FDR.