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Old 11-14-2011, 07:43 PM   #1
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Default steering and handling problems (Losi 8T 2.0)

i guess i'll list the specs, then the problems

i have a losi 8T
-21 VZ-B with JP-4 pipe
-werks clutch, aluminum shoes, green and gold springs
-stock Losi RTR servos (i know this is some of my problem)
-front shocks have 40 wt and 2.3" x 5.0 springs
-rear shocks have 35 wt and 3.1" x 4.0 springs
-1 degree of camber all the way around
-all shock positions are in the middle
-tires are pro-line hole shots (soft)

the only two tracks i frequent are nearly identical conditions, covered blue groove that is hard packed and fairly smooth, they do tend to get just a little dusty but its usually not too bad.

my problems that i'm having is the truck seems to do nothing but push around the track instead of steer around corners, the other problem is it tends to get pretty wobbly when coming out of corners and landing from jumps

ive tried running different oil wts and spring combos but with no luck, even tried different tires and still nothing

my next plan of attack is going with higher torque servos and a heavier servo return spring on the steering

i guess what i'm needing to know is if their is any tips, tricks or suggestions anyone could send my want to somewhat help me out or get me heading in the right direction
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Old 11-14-2011, 07:55 PM   #2
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my problems that i'm having is the truck seems to do nothing but push around the track instead of steer around corners, the other problem is it tends to get pretty wobbly when coming out of corners and landing from jumps
If your pushing you might need to go lighter in the rear diff. My 2.0 I can go from 3K down to 1K in the rear depending on the track. I have a few diffs done up ready for that though. I'm at 1.5 degrees in front toe out as well, that will give the inside tire tons more bite and it helps pull you around the corner instead of being pushed.
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Old 11-14-2011, 08:00 PM   #3
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What diff oil weights are you using? Front-Center-Rear. This will make a big difference as well. I ran 5-5-2 and found it had way to much steering for my taste and not enough power to the ground, then changed it to 7-10-5 and found it good for me enough on power to the ground and enough steering while that power was being put out for me also the off power steering was really good as well. Just another aspect to look at.
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Old 11-14-2011, 08:25 PM   #4
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Print out drakes setupsheet start from there buy the v2 tower run the sort link on the inside hub hole upper hole on tower. Make sure you have toe out on the front try using the short ankerman.
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Old 11-14-2011, 10:10 PM   #5
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The main items I would check are these in this order:

Steering EPA- make sure your steering servo is turning your hubs to full lock but not over doing it to the point it is pulling the A-arm. On both sides, sometime they are not always equal.

Diff fluid- Since you have good rubber and you steering servo fully turns your wheel this is next. You will have to go with thinner front to start. I know stock diff oil is at 7k if you have not changed it. Go down to 5k or even 3k in the front. This will allow the diff to work easier which will result in faster turn in and less pushing. If you lighten up the rear as well it will allow your back end to rotate around the turn faster too.

Try these and let us know how it goes.
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Old 11-15-2011, 04:23 AM   #6
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Print out drakes setupsheet start from there buy the v2 tower run the sort link on the inside hub hole upper hole on tower. Make sure you have toe out on the front try using the short ankerman.
i'll try using the short ankerman and see what benefits that will give me, with a mortgage, a 4 year old and a wife in nursing school i have to budget what i spend on rc lol but i'll try changing it up on my tower


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The main items I would check are these in this order:

Steering EPA- make sure your steering servo is turning your hubs to full lock but not over doing it to the point it is pulling the A-arm. On both sides, sometime they are not always equal.

Diff fluid- Since you have good rubber and you steering servo fully turns your wheel this is next. You will have to go with thinner front to start. I know stock diff oil is at 7k if you have not changed it. Go down to 5k or even 3k in the front. This will allow the diff to work easier which will result in faster turn in and less pushing. If you lighten up the rear as well it will allow your back end to rotate around the turn faster too.

Try these and let us know how it goes.
from what everyone is saying it seems to be that i'm running too thick of diff oil...i luckily i have 4 sets of diffs i'll let you guys know what kind of results are yielded as soon as i get a chance to try it out

as far as the epa on the servos, i'm not exactly too sure how that's done, do you think you could briefly explain the process to me?
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Old 11-15-2011, 04:55 AM   #7
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as far as the epa on the servos, i'm not exactly too sure how that's done, do you think you could briefly explain the process to me?
If you took your steering linkage off your servo and turned your wheels all the way left and right (by hand) and they were moving farther in both directions your not getting all the throw from the servo.

Your end points are done off your TQ. First, are you running a 2.4? You would have to go in the radio and set up how far you want your servos to push or pull by moving a dial on the TQ once you are on the right screen.

When I posted I was assuming they were set up. If your not getting the full throw of your steering thats a huge problem.
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Old 11-15-2011, 07:23 AM   #8
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Your transmitter will have the end point adjustment. Basically, it will tell the receiver how far you want to allow the servo to rotate.

Since your hubs have a limited turning radius, you want to limit the amount your servo rotates when at full turn. Letting it turn to far will wear on your servo and eventually cause failure.

I have always had trouble getting this right, but I think its because the 8T has so much play in the front wheels. Anyway, look in the manual for your radio system. It should have instructions for adjusting the endpoints.

FYI do this for your throttle to if you havent already.
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Old 11-15-2011, 09:29 AM   #9
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Originally Posted by carlwilson417 View Post
i'll try using the short ankerman and see what benefits that will give me




from what everyone is saying it seems to be that i'm running too thick of diff oil...i luckily i have 4 sets of diffs i'll let you guys know what kind of results are yielded as soon as i get a chance to try it out

as far as the epa on the servos, i'm not exactly too sure how that's done, do you think you could briefly explain the process to me?
Before you change the ackerman and diff, ensure you steering EPA is adjusted for max throw. Then change diff if you are still not happy.
What kind of transmitter do you have?
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Old 11-15-2011, 10:12 AM   #10
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Sounds like you've got some good starting points.

Remember, try one thing at a time so you know how each change reacts.
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Old 11-15-2011, 10:18 AM   #11
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One other thing to check: your servo saver. If you have full throw on your steering when you have the wheels lifted off the ground, but you don't when the wheels are on the ground, your servo saver may not be set tight enough. I had that happen to my Ten T. The collar backed off over time.
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Old 11-15-2011, 10:49 AM   #12
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One other thing to check: your servo saver. If you have full throw on your steering when you have the wheels lifted off the ground, but you don't when the wheels are on the ground, your servo saver may not be set tight enough. I had that happen to my Ten T. The collar backed off over time.
+1 to this. Most trucks suffer form this issue. The servo saver needs to be checked frequently.
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Old 11-15-2011, 12:01 PM   #13
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Print out drakes setupsheet start from there buy the v2 tower run the sort link on the inside hub hole upper hole on tower. Make sure you have toe out on the front try using the short ankerman.
+1. The losi 2.0t has to be one of the easiest truggies to dial in at any track. Use drake's standard setup (You can skip the incline spindles for now), and follow the rest of the setup exactly. Ride height, shock position, everything. Buy some new servos and new servo saver plastics/spring. Then you'll have an excellent starting point.

Make sure you have your brake bias set correctly as well. You should have at least a 70/30 bias towards the rear brakes. If you have excessive front brakes you will not be able to rotate the truggy.

A lot of losi handling problems occur when the setup deviates from the drake setups.
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Old 11-15-2011, 12:17 PM   #14
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+1.
Make sure you have your brake bias set correctly as well. You should have at least a 70/30 bias towards the rear brakes. If you have excessive front brakes you will not be able to rotate the truggy.
This is a big one I forgot to mention!!!!! If your front brakes are too strong it will lock the front wheels up and not allow them to rotate through the corner. This will cause the truggy to push also. You will have to use the adjustment on the throttle linkage to reduce your front brakes.
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Old 11-16-2011, 08:12 AM   #15
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This is a big one I forgot to mention!!!!! If your front brakes are too strong it will lock the front wheels up and not allow them to rotate through the corner. This will cause the truggy to push also. You will have to use the adjustment on the throttle linkage to reduce your front brakes.
i'll be sure to check that as well...

it seems i have a fairly decent list of things to check, just need to get some time off to head to the track and start making some adjustments

i did finally figure out how to do the EPA

i'm going to start by adjusting the end points on the steering servo and see what results are yeilded, then adjust front and rear brakes for a proper ratio, then try different diff fluids and see what suits my needs best and go from there

i really appreciate all the help you guys have given me and as soon as i'm able to do so i'll be sure to let you guys know what changes i did make and how they have affected the handling of the truck

thanks again!
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