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Old 03-20-2004, 03:07 PM   #9376
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If:
You don't have a serious tweak...
You don't have a tire unglued...

I believe it's not your set-up...
Search for a seized bearing...
Crazy diff...
Crazy one-way...
Or something in your transmission...

If suddenly a car spins down the straight it means some serious transmission problem.
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Old 03-20-2004, 03:27 PM   #9377
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Sorry I didn't make this clear, but I only have spinning problems when turning under power or with a good amount of momentum.....
I love the car though, spins very free, belt drive is nice and smooth and not quite as jerky as the tc3.
The car may be slightly tweaked, I didn't check it while I was at the track, but this has been happening for about 3 race days in a row now, and the first two times i'm sure the car was un-tweaked....
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Old 03-20-2004, 03:50 PM   #9378
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Default 1st race

Just got back from my first race day and i have some questions
1st i made the B main and came 3rd

a) 1 ran 1800 6 cell packs (no namers) for the longest time with decent amounts of speed. come today i had zero punch. i was able to cruise around the track with the hammer down and be so slow i wouldnt have to brake. this on what they considered a very technical course. all 3 of my packs were this way. 1st thought was of course the batts. so someone lent me a 2400 for the B main. i had good punch off the start but was in the same boat come lap 3. My thinking is ESC or motor. any ideas?

b) every time i hit the wall i had to re-adjust my steering through my radio. is that common?

thanks
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Old 03-20-2004, 04:09 PM   #9379
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cardboard,

2 degrees toe-in on the front? Also, you might need more total caster for carpet, it will make the steering more forgiving.

try this setup, it's very fast on carpet.

front
camber: -1
toe: 0
roll center: losi low
kickup/anti-dive: -2(I beleive this is the 0F mounted in the bottom holes of the front bulkhead, can't remember, just sold my car a week ago)
caster block: 6(make sure L for left goes on the left side and R for right goes on the right)
camber link on tower: above and inbetween the 2 middle holes-you will have to custom drill this hole on the tower.
shock location on tower: 3rd out
droop: 2 on gauge
shock piston: 57
oil: AE 60
spring: losi orange
ride height: 5
arms full forward
diff-a bit tighter than rear
standard ackerman
foams: jaco 28mm plaids(purples with a strip of orange on outside of tire)

rear
camber: -1
toe: -2
roll center: losi low
anti squat: -2
camber link on tower: very top, very inside
camber link on hub: hole closest to wheel
shock location on tower: 3rd out
shock location on arm: hole closest to wheel
droop: 4 on gauge
shock piston: 57
oil: AE 50
spring: losi white
ride height: 5
arms full rearward
foams: jaco 28mm purples

Also, check the aluminum shock end balls to see if they have come out of the plastic shock ends, one of the fronts use to do this where it would be logged between the shock end and the arm.

Last edited by webspinner; 03-20-2004 at 04:31 PM.
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Old 03-20-2004, 05:28 PM   #9380
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hmm....just a thought.....would 0 degree rear hubs be causing this? I don't remember having this problem when I was using the stock 2 degree ones.....
Should I get rid of the 2 degree toe-in in the front?
thanks....
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Old 03-20-2004, 05:35 PM   #9381
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the stock ones are 0 degree hubs..

you take rear toe away by putting on either the 0.5 or 1 degree hubs on the 'wrong' side (left on right, etc.)
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Old 03-20-2004, 05:37 PM   #9382
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If your car is doing donuts, there is a problem in the drivetrain somewhere as gearless suggested. Check your wheel bearings especially; a hung bearing can cause one wheel to spin slower and result in a spin-out.

I don't see anything in your setup that could cause this. There has to be something wrong with the car.
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Old 03-20-2004, 06:15 PM   #9383
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Thanks guys......that was DEFINATLEY the problem, I found a few jammed ones.....all in the hubs.....
What is the replacement size I need? I see the manual lists them by 3/16" x 3/8", but what does that convert to in metric? 5x8x2.5 right?
Also, could someone please explain to me what the degree measures on the hubs mean? On the rear, 0.5 degree hubs mean 0.5 degree toe in, right? But what about the front hubs?
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Old 03-20-2004, 07:21 PM   #9384
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replacement bearings will probably be listed under imperial dimensions?


as for the rear hubs, the stock 0 degree hubs give you 4 degrees (2 per side, which is how it's written on the setup sheets on the losi website) total rear toe in no matter which side they are on because the 4 degrees of toe is inboard, meaning it's 'built in' to the angle of the arms.

0.5 degree hubs with the hub marked left on the left side and the one marked right on the right hand side will give you an extra 0.5 degrees on the 2deg stock, giving you 2.5 degrees per side (5 deg. total).

then also with the 0.5 degree hubs you can go down to 1.5 degrees per side (3 deg. total) by putting the hub marked left on the right hand side of the car, and the right on the left.

and then the 1 degree hubs will give you 3 per side (6 total) degrees on right way around or 1 per side (2 total) if on the opposite side of the car.
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Old 03-20-2004, 07:25 PM   #9385
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Hey guys,

Im trying to do the Matt F setup where you take the turnbuckle from the servo and put a longer one in and connect it to the center of bell crank.

The question I have is do you connect it to the center of the bell crank or to the right side of the bell crank? I have seen ppl do both.


Thanks
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Old 03-20-2004, 07:31 PM   #9386
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i have that setup and im useing the same servo saver that the kit brings .. and works fine. but if im not doing it right please tell me !
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Old 03-20-2004, 07:50 PM   #9387
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cardboard, I don't know how much kickup you are running but 0 degrees of caster is going to give the car a massive amount of steering. Like I said, you might want to get the 6 degree blocks and lay the arms flat. On carpet, at least run 4 degrees total caster.
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Old 03-20-2004, 08:18 PM   #9388
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ok....i'm kinda new to tuning cars so bear with me. from what i understand, anti-dive is negative kickup. is this right? can someone please explain caster/kickup/anti-dive to me? and how it is determined?
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Old 03-20-2004, 08:43 PM   #9389
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Sure cardboard,

Kickup is when the arms are angled up when looking at the arms from the side of the car, this also adds caster to the car.

Anti-dive(is negative kickup) is when the arms are angled downward when looking at the arms from the side of the car, this subtracts caster.

When calculating caster, you want to take the degree of caster from the arm and the degree of caster from the caster block so you will know how much Total caster you have.

Know with all this said, just the term kickup and anti-dive have their own effect on how the chassis will react despite how much or less caster they add. Kickup tends to help the car react better to a bumpier track where anti-dive doesn't and this is due to way the arms are angled when the car is in motion. It also affects how the receive weight transfer, kick-up tends to nose-dive into turns when weight is transferred from the rear and anti-dive tends to not to nose-dive when weight is transferred from the rear, again this is from the way the arms are angled.

Caster in the caster block is the amount the steering knuckle is angled downward, the more downward they are angled the more caster in the caster block.

Total caster is the amount of caster in the arm and the amount of the caster in the caster block added together.

IMO, more total caster gives a less steering response while less caster gives more.

Anti-squat is the same as kickup and anti-dive but in the rear. The more the front of the rear arm is angled upward the more anti-squat and the more the rear doesn't squat on and off power due to again the way the arms are angled which affects the way the rear reacts to weight transfer from the front.

Like I said, they both(arm angles and caster in the block) go hand in hand but they also have their own effect.

3 terms you need to familiarize yourself with;

Kickup/Anti-Dive
+
Caster
=
Total Caster

Last edited by webspinner; 03-20-2004 at 08:50 PM.
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Old 03-20-2004, 10:16 PM   #9390
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ah, ok, after reading through it several times i think i've got it. so do you measure it? on a stock xxx-s, the main block=total caster, right? But then how do the low/high roll pivot blocks affect it?
this is a really nice bb.....everyone is very helpful and, uhm, intelligent .
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