LOSSI XXX-S, Tips and Tricks, Open Mod, etc

[Micro-E]

Wow, this is could be a great thread (really helpful)! Thanks John for starting this.... I just started racing with a XXX G+ and would LOVE to hear any setup tips specifically for 17.5 rubber / asphalt.

[Pablo Diablo]

Originally Posted by Evoracer

John, in ref to your ESC is that the RS you're running? Couldnt find the R8 unless you're running that RX8 for 8th scale. Always been a tekin fan and obviously Florida has it's share of warm (otherwise known as "holy crap it's hot") days.

That is a RX8 in his car. RS's struggle in mod.

[nikkon]

How is the xxx-s doing compared to your tc5? You getting better lap times?

[Evoracer]

Originally Posted by Micro-E

Wow, this is could be a great thread (really helpful)! Thanks John for starting this.... I just started racing with a XXX G+ and would LOVE to hear any setup tips specifically for 17.5 rubber / asphalt.

Hey Erik, John probably has some great setups that were never published. There are great sources for those that are. www.teamlosi.com. , www.rc-setups.com. , www.losiboard.com.
Some good stuff all over the place.

[Evoracer]

Originally Posted by nikkon

How is the xxx-s doing compared to your tc5? You getting better lap times?

Can't help but smile about this question. An old fart like the XXX-S being compared to one of the current cream of the crop. Apparently the old fart still has some strong legs.

[paraletic]

Hey Guys Sorry forgot this wasnt the normal XXX-s thread, as id posted this in there already. and jus forgot an started typin away like as if ud all seen it already lol.
No belt secrets here, (prob not that good an idea either lol jus seems too work for now) I havnvt done heaps of testing on belts etc but after I broke the original belt that came with the car (2nd hand) i satrted lookin at belt options,Seeing i run a XXX-4 as well i grabbed a standard yellow belt from that and compared it too the xxx-s belts, i found IMO it was similar material too the yellow XXX-s belt, but very close too the Long belt conversion belt in length.

So i set it up using the long belt conversion arm and pulley and put the XXX-4 belt in. it seemed perfect.

so for me having one belt between the 2 diff cars just made more sense atleast for now until i find a better option???? (any ideas?)

Im only new too touring cars an relativly new too rc in general so Im open too any input on ideas etc.

[paraletic]

hey John i noticed in ya pics you had what i think is the dodge stratus shell on ya car??

hav you tried diff bodies on it? ie speed 6 or Ltc-r etc??

do they make much of a diffrence?

Cheers.

[John Stranahan]

Paraletic-Thanks for the update on the belt. I have one vote on the black belt. It could be that a harder finish helps it in stock.

Bodies-Thats the RTR body. I have not noticed much difference in touring car bodies of late. They are strangled by a fistfull of dimensions that must be met. Kind of like Nascar. Probably will not be able to notice a change in handling ever again.

I don't have lap times yet. Will be glad to help with setups. It is probably best to state a problem and we can work on correcting it.

HOPUPS

Here are some upgrades I thought would be useful for running mod at Mikes.

GPM Red Aluminum Shocks
http://www.asiatees.com/display.php?id=2862&brand=Team Losi&model=XXX-S&pid=1

Aluminum Wheel Hex
https://www.ssl-stormerhobbies.com/cgi-bin/seekpart.pl?src=ns&pn=LOSA9687

Locked Diff Pulley, standard 42 tooth XXX-S, JRXS
https://www.ssl-stormerhobbies.com/cgi-bin/seekpart.pl?src=ns&pn=LOSA3325

Aluminum Motor Clamp
http://www.asiatees.com/display.php?id=3445&brand=Team Losi&model=XXX-S&pid=1

Here is why.
I really only need those threaded adjusters to get the tweak just right. This is very helpful in mod and stock. Losi shocks are very good. They do sell threaded bodies. These were cheap and red.

My cars have a tendency for the axle pin to just rotated through a plastic hex with a 3.5 on board. The Aluminum hex is good insurance. I purchased medium width to catch every last bit of plastic on the wheels hex.

I installed the sandpaper locked diff rings. This is one innovation that may have been first tried on my previous thread. It is working fine. I am hoping this pulley will allow slightly more slip when in a crash with good grip while driving to protect the out drives. We ran locked front diffs on high grip indoor asphalt stock, as well, to rocket out of the corner.

The motor gets quite hot. The hope is for the Aluminum clamp to keep the motor plate cooler. The Aluminum clamp will keep its setting longer without retightening as the plastic clamp is not being stretched out with heat.

Track Sessions
I have had two track session with the car. This is what I notice different than the TC5. Both session were dusty and traction was low. I had more turn in. Part is due to the more flexible chassis. Another part of this is the fact that caster is set at zero on the available replacement c-hubs. I broke one when a speed control died on me. Normally I run 4 degrees of caster. Cornering is similar but I am more in control of where the nose of the car is pointing. When it gets pointed right I can start adding power (sooner than on the TC5). Acceleration is very straight. No arc. I can steer a little, though, when accelerating very strongly. I notice this on the straight with a chicane at the end. I can start pointing for the gap a lot sooner than before. This reduces the amount of braking needed. Not so with the TC5. So far I like the car a lot. I'll have to have another race to know if it's actually faster. We had very good traction by heat 3 in the last race. These small improvements are going to be magnified.

The car is several ounces too heavy. I have installed some aluminum screws to lighten it a little. Shock tower, Servo, Don't go crazy here. The titanium screw kit is too expensive to even consider. Lunsford Hinge pins might be in order. I think a graphite kit is worth an ounce but I am keeping mine Stiffzell.

Yes that is a Tekin 1/8 th scale speed control. It has not thermalled and does just fine with LRP motors. I had some trouble syncing with a Novak Ballistic series 3.5. I did not get full power. I highly recommend it for the hot states with powerful motors. I had an RSPro in the car. If you mount it on the side and blow air on the posts and bottom it makes 6 minutes most days. I had two SXX's fail. One caught on fire. The Tekin R8 works like a charm, even better than the old LRP TC edition before the SXX.

Tips for stock-You should take lengths to meet minimum weight. You can make the cutouts in the stiffzel chassis that the graphite chassis has with no ill effects. You can remove maybe 10 inches of 12 gauge wire from my setup I have pictured on page one; this will improve voltage at the motor. This will also remove 10 grams of weight. I have extra length for mod to keep things cool and in the solid state. Especially the solder joints.

Evo racer-The graphite car has greater torsional stiffness than the stiffzel car. I have measured it. About 30% more in spite of the cutouts. Use the stiff car on tracks with more traction. Add sway bars if traction roll becomes an issue or if the car is a little sloppy in its handling. The GTB, SXX or Tekin RS pro are all good for stock. Get the best of the line though as the on resistance is lower. That helps you in stock.

Pic-measuring torsional stiffness of a JRXS. I did similar measurements on the XXX-S. Stiffzel, then Graphite plus, then JRXS was the order from most flexible to stiffest.

The rear of the frame is clamped solidly in the milling machine vise. The front of the car can twist on the rod. A stiff hex aluminum rod and weight provides a little torsion. The dial indicator measures the flex.

[ICBeloitRacer]

Since I can make a noob post in here and not get flamed...

Are there any essential beginner tips for an aspiring XXX-S driver with very little on-road racing experience? I'm looking at picking one up for Vintage Trans-Am racing this coming year, running 21.5T brushless on 2S lipo. What would you recommend using as far as chassis, belt options, etc.? Like I said, I'm totally new to on-road cars, and the closest racing experience I have is 1/10 trucks on a carpet track. Any advice helps.

Thanks!

[Evoracer]

Originally Posted by ICBeloitRacer

Since I can make a noob post in here and not get flamed...

Are there any essential beginner tips for an aspiring XXX-S driver with very little on-road racing experience? I'm looking at picking one up for Vintage Trans-Am racing this coming year, running 21.5T brushless on 2S lipo. What would you recommend using as far as chassis, belt options, etc.? Like I said, I'm totally new to on-road cars, and the closest racing experience I have is 1/10 trucks on a carpet track. Any advice helps.

Thanks!

Our club was racing VTA also until recently when we switched to RCGT. What type and design of track are you on ? (example: indoor carpet/ technical/traction compound allowed)


Hey John, I know your intent was to create a "TECH" thread for the XXX-S but it appears the XXX-S and YOU hold enough interest that this thread will become Part Deux. If you want to set some ground rules just spell em out and we'll take some of these questions to the original XXX-S thread but.....you provided the water...now all the horses want a drink !!

[ICBeloitRacer]

Indoor carpet, the layout changes from week to week, so there's a good mix of technical and more open tracks. I'm not 100% sure about traction compound, but i don't think it's allowed.

[da_John_wee]

Hello every one, I read Every thread created by John Stranahan at least once. GREAT STUFF!

I read this thread brifley this morning but had no time to reply yet till now, one thing that I noticed is John used "RTR" version of the car and want to pointed out "RTR" version of Losi vehichle is not made of smae Stiffzel as regular kit (such as Original XXX-S kit realesed on 2001) so torsional stiffness test should be done separatley for RTR kit to be sure, if you take a look at close to following image John post it on 1st page you will see "RTR" molded on rear shock tower, that s not a stiffzel tower.

I'm pointing this out just to make sure people who follow John's set up and if you don't get same result on your Original kit xxx-s then now you know why.

BTW in my past experience with RTR plastic was horrible.

keep up the good work John, BTW have you ever bought a JRX-S type-R ? (or did I missed one of your thread?)

[Evoracer]

Originally Posted by ICBeloitRacer

Indoor carpet, the layout changes from week to week, so there's a good mix of technical and more open tracks. I'm not 100% sure about traction compound, but i don't think it's allowed.

Hey, that helps a bit. My personal choice would be the G+ for carpet. As for setups...take a look at 1 of my earlier posts in this thread. I mentioned 3 websites. You'll find a wealth of good carpet setups in them.

[John Stranahan]

Thanks for the posts guys.

First there are no real ground rules for my threads. I like them to stay on tech rather than chat. That's about it.

I did notice the plastic in the RTR is a different color and probably cheaper as every single part of the car is stamped RTR so there is no confusion buying packaged Losi parts. My "calibrated" hands, with which I twist every car that I look at, by grasping the car around both shock towers and giving the car a twist tell me the chassis is pretty close to stifzell in torsional stiffness. Maybe not quite so tough when you hit the boards, though. Stiffer than a TC3 less stiff than a Losi JRXS. The setup may not be much different than on a Stiffzell car. We never really setup the stiffzell car any differently than the graphite plus cars. Anyway there are probably lots of these RTR's around.

I never had the type R. I wish the introduction had been delayed and they had not produced the first version. I had trouble getting enough rear weight from the get go. I got the TC5 next.

Driving the Corner
ICBeloitRacer- You asked for the whole book at once. We need to break it down into pieces. Your carpet experience with the truck will be most useful. Hardly anything will change.

I thought I would talk about Driving the corner with at least medium traction in a XXX-S. It is slightly different than driving a full size car with huge inertia around a race course corner. Firstly I tried driving the XXX-S by slowing to the apex and then powering out (this is typically how a full size car is driven; brakes are gradually reduced to the apex, power is gradually applied there after.) Well once in a while the XXX-s, driven this way, would seem to stop completely in the corner. There is really not enough inertia in an XXX-S to drive this way. Combined with some motor and belt friction this caused the stalls. Some guys would use radio setting to overcome this like adding some forward throttle trim. I found this just a pain especially at the start of the race where you have to hold brake. What I do now is I slow in a straight line. This may require a brief stint in neutral (or on slippery tracks just a drop to part throttle). Then I power through at fairly constant speed the first part and then somewhat past the apex. Then you can roll on throttle as fast as the traction will allow. It is important for best speed, not to spin the tires out of the corner. The only way you know you are spinning is the car just does not accelerate as quickly. All else is the same. If your cornerweigths are good the car is well behaved and accelerates straight even if you spin the tires a little. If you spin the tires with poor corner weights the car will tend to dart to the boards when you spin the tires. So slow to the proper cornering speed (slow is fast) power through the corner on a tight line, roll on throttle out of the corner. And there you have it.
Now a TC3 can be driven quite deep into the corner before adding the power. There is less fricition and less tendency to slow. Some drag brake can be added if the car is not slowing fast enough. Usually 10-15 % dragbrake is enough.

Kickup=Caster
I took note of the setup on the RTR and made a bunch of changes. I'll report on these If I have any luck. Turns out there is quite a bit of kickup on the car. Kickup is when the inner hinge pins on the front are angled upward as they go forward (like on an off-road buggy) This adds to the caster setting and may be why we are getting 0 degree caster blocks. This also may add on power steering with a locked diff so I removed it.

[ICBeloitRacer]

Originally Posted by Evoracer

Hey, that helps a bit. My personal choice would be the G+ for carpet. As for setups...take a look at 1 of my earlier posts in this thread. I mentioned 3 websites. You'll find a wealth of good carpet setups in them.

From your earlier posts, that's what I was leaning towards. What's the lowdown on the belts, I've been reading about various colors and lengths and it's all a bit confusing for a simple off-roader Also, how hard is the XXX-S to wrench on?