Go Back   RCShortCourse.com Bulletin Board > ShortCourse General Tech > Newbie ShortCourse

Notices

Loading
Like Tree4Likes
  • 1 Post By elmoracer
  • 1 Post By elmoracer
  • 1 Post By mkjprice
  • 1 Post By FlapJackFred

Thread: Motor Setup

Reply
 
LinkBack Thread Tools
Old 08-09-2017, 01:51 PM   #1
Newbie
 
Join Date: Aug 2017
Posts: 5
Angry Motor Setup

I am an old school guy, and I am trying to setup a 2wd SCT truck for a race this Saturday. It is a Kyosho Ultima (please don't tell me to just get a new truck) with a Tekin RX8 V3, and a Pro4HD 4300Kv motor. I have the Tekin Hotwire.

78 tooth Spur with 22t Pinion all 48 pitch. Running a 2s 7200mah 80C pack.

Spektrum DX4C radio.

K- now the problem. I cannot keep the rear tires stuck. I realize I probably overpowered the truck with my motor choice. I have used the hot wire to turn the torque all the way down, advanced the timing, and softened the throttle curve on the bottom end. When I give hardly any throttle, it whips the back end around to the front.

I can't put a bigger pinion without modifying the motor plate (not enough adjust-ability)

I do have a spare Traxxas Velinion Motor that I could install. Not sure what to do. Please help!!
mkjprice is offline   Reply With Quote
Sponsored Links
Old 08-09-2017, 02:29 PM   #2
Addict
 
Join Date: Feb 2010
Location: Beckley WV
Posts: 1,289
Default Re: Motor Setup

First, are you on the right tires? That is the first place i would look myself. What tire is everyone else using at your track? That can be a good place to start. Second, is there something going on with your setup? Maybe a camber or toe issue? Are you running the truck in rear motor or mid motor configuration (if its an SC6)? Third, try experimenting with throttle expo to allow you to get the truck moving before the horsepower coming on like a tidal wave. Fourth, you can use a larger pinion with a smaller spur to achieve the same result without modifying the motor plate. Finally you can loosen the slipper a little to soften the blow that the motor is delivering. I hope this helps you get your Ultima hooked up!
elmoracer is offline   Reply With Quote
Old 08-09-2017, 02:39 PM   #3
Newbie
 
Join Date: Aug 2017
Posts: 5
Default Re: Motor Setup

Tires are a big mystery to me - The track I am racing at is at our county fair, and is a horse riding arena converted to a track for the day. Asking the guys at the track would give me a bunch of redneck empty stares.

They do a pretty good job of prepping the track for the day, and I would say it is a softer more laomy type dirt, and they do wet it before the first race.

I have a set of soft compound pin type tires coming that will be here for the race.

Camber at the rear is flat - going to change it to a little negative camber by a couple degrees. I have negative expo on the radio already - may try some more.

Living in Rural Utah my options to change spurs and pinions are pretty limited as I have to mail order everything.

It is a Rear Motor setup car.

I plan to also move the rear shocks to the most inward position - I have heard this makes it more forgiving for traction.

Thanks for the ideas.
mkjprice is offline   Reply With Quote
Old 08-09-2017, 02:46 PM   #4
Addict
 
Join Date: Feb 2010
Location: Beckley WV
Posts: 1,289
Default Re: Motor Setup

If you can get your hands on a set of Pro-Line Gladiators or something like that, that would be a decent place to start. If they don't pack the surface down and its just the loose soil that riding arenas use, I would go with Badlands (I know that sounds rather extreme but those tires will bite into the loosest soil imaginable). Being rear motor will help and adding a little camber (one to one and a half degrees should be all that you need) will aid in cornering without hindering forward traction. Do you have an option to shorten the wheelbase by a few millimeters? That can help with forward traction as well. Finally, can you move the battery back any further? If not adding a little weight to the rear may help (I use pinewood derby weights in the rear of my SC10).
mkjprice likes this.
elmoracer is offline   Reply With Quote
Old 08-09-2017, 02:48 PM   #5
Newbie
 
Join Date: Aug 2017
Posts: 5
Default Re: Motor Setup

would you possibly go with a slightly bigger tire - maybe a 2.8 over the 2.2?
mkjprice is offline   Reply With Quote
Old 08-09-2017, 03:13 PM   #6
Addict
 
Join Date: Feb 2010
Location: Beckley WV
Posts: 1,289
Default Re: Motor Setup

That would create its own set of problems. I would stick with the 2.2/3.0 size. On that type of surface you want a tire that can penetrate the surface and find traction and a larger, wider tire will float on top and have less ground pressure. Check out my basher tire comparison for some notes on how each tire works on loose surfaces and that should help on the type of surface you described. Basher Tire Comparison: Is there an "Ultimate" All-Around Tire?
mkjprice likes this.
elmoracer is offline   Reply With Quote
Old 08-09-2017, 03:16 PM   #7
Newbie
 
Join Date: Aug 2017
Posts: 5
Default Re: Motor Setup

Fantastic Write up about the tires - I order a set of 2.2 Badlands - seems like that might be my best shot for a hope of traction. Your help has been awesome - thanks a ton.
elmoracer likes this.
mkjprice is offline   Reply With Quote
Old 08-09-2017, 03:35 PM   #8
Newbie
 
Join Date: Mar 2017
Posts: 21
Default Re: Motor Setup

Quote:
Originally Posted by mkjprice View Post
Tires are a big mystery to me - The track I am racing at is at our county fair, and is a horse riding arena converted to a track for the day. Asking the guys at the track would give me a bunch of redneck empty stares.

They do a pretty good job of prepping the track for the day, and I would say it is a softer more laomy type dirt, and they do wet it before the first race.

I have a set of soft compound pin type tires coming that will be here for the race.

Camber at the rear is flat - going to change it to a little negative camber by a couple degrees. I have negative expo on the radio already - may try some more.

Living in Rural Utah my options to change spurs and pinions are pretty limited as I have to mail order everything.

It is a Rear Motor setup car.

I plan to also move the rear shocks to the most inward position - I have heard this makes it more forgiving for traction.

Thanks for the ideas.
Definitely the biggest challenge will be tire selection. I've been there with the awkwardness looks from local drivers...acting like everything is a big secret. Pro-Line M3 Gladiators, or M3 Caliber 2.0s depending on the amount of "loaminess".

The track is put together just for an one event? Anytime to practice?

Like been said, a bit of negative camber...let 'er rip. I'd probably go with a bit higher roll center (move inner camber link down) on the rear for low traction track.
elmoracer likes this.
FlapJackFred is offline   Reply With Quote
Old 08-09-2017, 03:37 PM   #9
Newbie
 
Join Date: Aug 2017
Posts: 5
Default Re: Motor Setup

You can get about 20-30 mins practice. The horse people get pissed that we want to do this, but don't seem to care about the Demolion Derby in the main arena. - I guess the purse is different for the rc race vs the demo derby. Total purse for RC is about $150 bucks and some t-shirts - Demo Derby total purse is $75k
mkjprice is offline   Reply With Quote
Reply



Motor Setup - Similar Threads
Thread Thread Starter Forum Replies Last Post
newbie motor setup Rogschevelle Newbie ShortCourse 6 04-12-2013 08:20 PM
8.5 or 10.5 Motor/Esc setup azurebluemach1 Electronics 22 09-17-2011 02:00 AM
Motor/ESC setup Flatusboy Losi TEN-SCTE 6 03-29-2011 10:50 AM
Will this ECS/ Motor setup work DPits1976 Traxxas Slash 14 02-04-2011 09:03 PM
Motor Setup Alan Team Associated SC8 3 10-04-2009 08:25 AM
Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -7. The time now is 11:39 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO ©2011, Crawlability, Inc.
Copyright 2004-2007 RCShortcourse.com