1/12 forum
Yes, akermann is the turning difference of the outside versus inside tire.
The below is just my impression, the actual facts could differ.
When I say steering aggression, I'm referring to the arc the toe links take on the servo. With the servo flat, the outside wheel's tie rod inner ball is going down. That means, with the same speed servo and all other things being equal, the initial steering speed off center is quick, and is then slowing down, and the inside wheel is turning at a fairly constant rate.
With the servo angled, the outside toe link is rising, so the initial turning speed is a bit slower, but finishes turning more aggressive. The inside wheel can get to a point where it just stops turning while the outside still has some turning angle left to go, in certain configurations, usually with a lot of akermann apparent.
Of course, there's exceptions, special cases and a lot of variables that can change everything all around as well. Depending on the chassis and front end you're running, it's still trial and error, with a handful of shims to see if you can get exactly what you want.
The below is just my impression, the actual facts could differ.

When I say steering aggression, I'm referring to the arc the toe links take on the servo. With the servo flat, the outside wheel's tie rod inner ball is going down. That means, with the same speed servo and all other things being equal, the initial steering speed off center is quick, and is then slowing down, and the inside wheel is turning at a fairly constant rate.
With the servo angled, the outside toe link is rising, so the initial turning speed is a bit slower, but finishes turning more aggressive. The inside wheel can get to a point where it just stops turning while the outside still has some turning angle left to go, in certain configurations, usually with a lot of akermann apparent.
Of course, there's exceptions, special cases and a lot of variables that can change everything all around as well. Depending on the chassis and front end you're running, it's still trial and error, with a handful of shims to see if you can get exactly what you want.
I played around with it in the early days of 1s. 19t was SLOW! It seems brushed motors were hurt more by the voltage reduction. Previously I had been running that 19t against 10.5 boosted with all of us running 4 cell and winning with it but 1s, it was more like a 17.5.
Hi Trev, here's a pic of the basic chassis:

This is with the battery in the furthest forward position (slightly further forward than the standard forward position).
Got a couple more tweaks since I made this, just tweaks, nothing revolutionary!
Cheers mate!

This is with the battery in the furthest forward position (slightly further forward than the standard forward position).
Got a couple more tweaks since I made this, just tweaks, nothing revolutionary!
Cheers mate!
That chassis looks much longer than the current one with the battery across. What's the wheel base on that compared to the current car? To me it has to be longer because how else can you have the battery mounted lenghwise and still have all that room for electronics behind the servo like it did with the battery across?
Tech Master
iTrader: (13)
Joined: Jul 2011
Posts: 1,117
From: Austin, TX
That chassis looks much longer than the current one with the battery across. What's the wheel base on that compared to the current car? To me it has to be longer because how else can you have the battery mounted lenghwise and still have all that room for electronics behind the servo like it did with the battery across?
Tech Rookie
Joined: Dec 2010
Posts: 12
Hi,
I have an 1/12 CRC XL with an 1S 120A esc Hobbywing and a 13.5t Speed Passion motor. But I have a problem, after 2 or 3 rounds the speed drop's quite fast and the temp. of my motor is hot (80/90*Celsius). But if I go smaller in pinion or bigger in spur it doesn't change.
If I look at my settings in the Hobbywing 1S it is quite normal, I guess.
But when I change my settings, my car is going slower, so I have to have a perfect setting in my esc.
Can somebody tell me what settings I have to have in my Hobbywing?
I have an 1/12 CRC XL with an 1S 120A esc Hobbywing and a 13.5t Speed Passion motor. But I have a problem, after 2 or 3 rounds the speed drop's quite fast and the temp. of my motor is hot (80/90*Celsius). But if I go smaller in pinion or bigger in spur it doesn't change.
If I look at my settings in the Hobbywing 1S it is quite normal, I guess.
But when I change my settings, my car is going slower, so I have to have a perfect setting in my esc.
Can somebody tell me what settings I have to have in my Hobbywing?
Tech Master
iTrader: (13)
Joined: Jul 2011
Posts: 1,117
From: Austin, TX
Yep. Turns out CRC is released a "shorty" 1S lipo.
And it is a new car:
http://www.rc50.com/modules.php?name...bum=67&pos=278
And it is a new car:
http://www.rc50.com/modules.php?name...bum=67&pos=278
Last edited by JamesL_71; 10-06-2011 at 09:29 AM.
Tech Master
iTrader: (13)
Joined: Jul 2011
Posts: 1,117
From: Austin, TX
Seems only possible now to make shorty batteries now that individual cells have super high C rating. Smaller packs will mean less overall mah ratings (for now), so it should balance out the voltage curves vs. standard 1S size packs somewhere down the line. The only real issue comes when the accessories added to the chassis begin to get light enough that we need to start adding weight like a Touring Car! Fear the day!
That CRC chassis looks the same as the current chassis to me, it appears a tad longer because of the photo angle. I doubt its changed. Remember, having a chassis thats too long makes the car feel lazy, and the rules dictate a certain max wheelbase. I also have a faint memory of one of the Calandras saying that they weren't going to lengthen their car wheelbase at some point a few months ago (maybe longer) in opposition of the current trend. I will note this: My current Gen-XL is nearly exactly the same wheelbase as my ancient Carpet Knife 3.2.
Last edited by DesertRat; 10-06-2011 at 12:41 PM.



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