Hmm, I should've investigated this first. I am going to run HV and I figured the better the capacity the longer it would stay at high voltage, so I got a pair of 9000mAh Zeee LiHV batteries. Guess I should look into some ~6000mAh short packs?

If we go with a shorty pack in a TT-02........what does everyone use to keep the battery in place front to back given the extra space created by the smaller pack? Is it TCS legal?

Figured I might as well throw up a pic of where my little guy is at.......because pics make people smile.


https://cimg4.ibsrv.net/gimg/www.rct...186296ca6.jpeg
Current porky weight with body and wing.
https://cimg5.ibsrv.net/gimg/www.rct...e66ef7dab.jpeg

I use small foam blocks as spacers.

+1 for foam.

you’ll go just as fast with 4000mah packs with mabuchi

So I could easily use on of my Reedy shorty packs in 7.6V 4000mah from my TLR as I have the correct adapter from bullets to the T plug on the 1060.......with a block of foam and drop the weight and push it back towards the middle of the car vs. the heavy front left wheel I have now.

Of course I am guessing for TCS I would have to use the full sized pack for a stock(ish) class, right?

EDIT: I put one of my shorty 4000mah batteries in with the proper leads and a small block of foam to keep the batteries weight out back for now and it came in at 1392 grams with the body......so about a 50 gram reduction. The car alone with no body or battery is ~1059 grams as is.

Only Euro Truck requires a full size pack.. so yes.. go ahead and play around with the shorty battery placement.. when using the corner scales, keep in mind that your shocks/springs are part of the equation.. gets complicated.. but your cross weight is way off.. even with the heavy battery on the left you are biased to the right.. time to take a close look at your shocks.. one thing I do.. I use grey color shocks for the rear.. black for the front.. that way I never accidentally install them backwards.. anyway.. if you added o-rings to limit droop.. start with making sure front and rear pairs are the same length at full droop.. next take off the springs and see if they have the same rebound.. if not.. time to check for air.. make sure it is the correct weight oil.. same piston in both.. lots of things to fiddle with..🖖

7.4V 4000mAh will go as fast as 7.6V 9000mAh? or 7.6V 4000mAh will?

Yes, since you are only allowed to charge both of them to 8.4V.. but the 7.6 LIHV batteries will typically also have a higher C-rating.. meaning they can discharge faster, giving you more punch.. that’s why I like the Protek batteries.. 7.6 LIHV and 130C at a reasonable price.. but I would choose a higher C-rating over the higher voltage rating.. as for the mAh rating.. think of that as the number of gallons in your tank.. since we only race 5 minute heats.. you don’t need 9000 gallons.. you basically carry around a lot of extra fuel that you won’t use..

The track I want to race at allows HV, up to 8.7V, in stock TT02.

Cool - it all comes down to the discharge curve of your battery.. if you compare normal Lipo with HV Lipo you’ll see that you will burn off the extra voltage very quickly.. at which point there really is little difference.. that said.. that extra speed for the first 30 seconds can get you out in front of the pack.. that’s why in most races you will see that they restrict the max voltage to 8.4 or 8.44.. at that point there is no difference between a HV Lipo and a classic Lipo..

Good stuff. I rebuilt all the shocks this week and just installed the Yeah Racing front universals last night. Noticed I had flipped a front A-Arm while doing the pivot balls the day before, swapped that around, front end is in good shape, front shocks I am running heavier oil than rear as I needed to stiffen it up. Similar rebound on all shocks. I will hit them with the calipers to check length. The O-ring I used in the rears are slightly thicker than the ones in the front by choice.

With the shorty pack I can move it around but the motor is just a heavy item on that back right corner. I'm not sure how to get the cross weight more in line. I played with preload to see what happened on the scales and it felt odd to play with preload unevenly on the shocks so I ditched that idea. I also won't have a chance to get it on the track until next week........

If I go as far to try and corner balance, I do always end up with uneven pre-load on the shocks. This is how you can shift the weight around without adding more weight to the chassis. I've never had any issues using this method.

Thanks for the "gut check" there as I was able to play with some preload spacers, just the smallest change on the opposite corners got me to the updated weight with body etc. below. I'm happy with the cross-weights being 50/50 and feel this is probably a solid place to start back on the track.

The only thing that I am slightly concerned about is that I need either drop my front ride height by 1mm or raise my rear as I am 6 front 5 rear right now. Of course I could shift my shorty pack forward which then will throw off the cross weights again but.......


https://cimg6.ibsrv.net/gimg/www.rct...00b624410.jpeg

That looks much better already! Definitely lower the front to at least be the same as the rear, in general you want to be as low as allowed, and raise the rear a little for better turn-in. Also.. Tamiya makes lots of different tires.. they don’t necessarily all work equally well on a track.. if it’s open tires where you race.. see what the locals are using.. it will make a big difference..

Thanks for the thoughts.

At the local track we are running spec PowerHobby brand tires........it is what it is....BUT they allow any PowerHobby tire so that allows for some experimentation. I also can sauce and the first time out I didn't have any of that ready to go......I do now :-)

I can play around with the pre-load spacers to get the rear up a touch but possibly keep the same level of slight offset to stay close to the 50/50 cross balance.

Since I cannot get to the track for a few days I have been setting up both the TT-02 and my TLR this past week. I did some additional work on the TT-02 as while I was able to get the balance better a couple days ago, I was still front-high vs. the rear. So I had to swap back the rear shock mounting positions to get back to where the rear is slightly higher. I was able to swap out rear springs to a.lighter set, which allowed a little more sag in the rear and I think that will also help the rear end hook up a bit better under power.

After the spring and shock position swap I then rebalanced things with pre-load......and here is where I landed and where I will start next week's race night for setup.


https://cimg7.ibsrv.net/gimg/www.rct...7bc2059f8.jpeg

I know that feeling.. you been tinkering.. not being able to get out and try it on the track… the suspense.. definitely let us know how it goes when you finally get it out to the track🖖

Hey guys, I'm looking into buying a TT-02 car. I'm presently in Orlando and I'm looking for an indoor on road track to start at. Any ideas as to where I can check out and get a feel of the place? This is the 1st car I've bought in about 30yrs. I raced Tamiya when I was kid and now that I have time once again I'm wanting to get back into rc racing.

Not familiar about the tracks in Orlando, but this is a good start https://www.rctech.net/forum/florida-racing-54/

Theres nothing wrong with the TT02 but that might not be the best racing setup for your local track. Check out the locals first then get your car choice after that.

Well.......got the updated TT-02 out on the track this evening and it was an adventure.......I changed so many things over the past 2 weeks that it needed a lot of dialing in., I went from no grip and sliding around to too much grip and traction rolling carrying speed into corners. That was all my fault as I sauced the tires based on advice and I really didn't need it. In fact I finally got my crap together for the "Main" (small classes and fun informal Thurs night racing) and was able to get some consistent laps in. Gluing up the side wall on the front tires helped a ton.

The upgraded Tamiya aluminum and plastic servo saver was a wild piece of crap waste of money and failed during practice laps, went with a straight up servo arm........

Once I got the tire and traction situation dialed in the car was decent.......I need to leave it alone for a bit and just start with this setup next week. But the TT-02 is stupid basher fun......

Once you get to the point where you know that the car is fundamentally sound, you definitely want to use small incremental changes to dial it in for track and track conditions.. until you get to that point.. big changes will show you how it’s affecting the car much better.. I like to overdo changes.. see what the effect is.. then dial it back..

I do the same thing as far as changes, and I am normally a firm believer in the scientific method of making one change at a time, and in this case all that went out the window as I changed so much over the past couple weeks. I wouldn't say the car is dialed in still but it is no longer totally off the reservation as it was earlier in the night.

I had to stiffen up the front shocks a ton as the new tires were so grippy. I may pull the spacers (quick track side adjustment) and move to stiffer springs in combo with glued sidewalls and start there.

All good......right now with the TT-02 I don't "drive" it.....I "guide" it around the track.

Thanks for the tips and support.

Good thinking, I try to tell people to use a basic servo arm and spend the extra $15 on a good servo. It's a brushed on-roader with the wheels tucked in and behind a giant foam bumper, you're probably not going to break your servo.

And if I do......it's $60.....not the end of the world. I come from a world of racing Mountain Bikes, a tire is $80-100 lol.......with RC you gotta pay to play and if you do play, you will break things, it is all part of the gig.

The only thing that kinda sucks is that if I race a TCS (or Box stock) event I am "gray" on whether the straight servo arm is legal as it is not "built to kit specs" but their kit spec is crap.......IMHO

Tamiya do sell direct mount servo horns (42248/42249) that would be fully legal. Personally I use the High Torque Servo Saver with a strategically placed drop of CA glue, rock solid during normal use.. but it will break loose on a big hit and still do its job..

Good call on the Tamiya servo horn, thanks, didn't see that previously.

I have their 54752 package and that servo saver is the wild POS that failed after a few laps.......but I also did not put any glue on it.

While I'm not sure if I will do a TCS this year as right now I am struggling locally still, but the car is getting "better" and who knows in a couple weeks of racing I can feel confident with it enough to at least go bang around with everyone else.

Needed to drill some holes in these RW gears because only 2 lined up, they would have held just fine but that's not as fun as making a tool to add 2 more!

https://cimg1.ibsrv.net/gimg/www.rct...2ae4469401.jpg
https://cimg2.ibsrv.net/gimg/www.rct...19f614fa93.jpg
https://cimg3.ibsrv.net/gimg/www.rct...f229149ac4.jpg

TA02R
 

For peeps who purchased the TA02r kit. I noticed the gear diffs did not come with any type of seal gasket. I wonder if this works just fine without leaking oil or are they designed for use with grease only.

I believe they're meant for grease only, but many have said they've used extremely heavy diff oils with success. I imagine it probably requires frequent servicing. The sealable diffs are pretty inexpensive for the TT02. And if you have the R, you're already set with steel dog bones.

I was wondering how long it would be until Yeah Racing come out with this:
https://cimg6.ibsrv.net/gimg/www.rct...ab4a63f948.jpg

Take a look at the XV-02 gear diff. It is a drop-in and worlds better than even the TT02RR diff.

Is that different than:

Tamiya TT-02 Oil Gear Differential Unit 54875 OP-1875

I just packed my TT-02R front diff with 30K grease but my rear is still just AW......but I am also scratching my head at possibly spending like $60 on 2 diffs when the whole car was $150 lol

Then again I already have $60 worth of steering linkage and universal upgrades

This is a fair observation. I think upgrading a TT02 or TT02R is more for the fun of it, or for racing that requires a non-S variant chassis. Otherwise you're better to get an SRX, or some other more modern platform. I typically run the $22-ish sealed diff in the rear, and then the $15 locker up front. Ends up being a bit less expensive and an overall good package.

I'm trying to walk the thin line of being close to TCS compliant if I want to run a TCS class however local TT-02 classes are a little looser and some live by the "if the upgrade is Tamiya then it is legal" and others claim "box stock" but that is so vague when you can buy a TT-02R or RR type kit......assuming everyone could technically upgrade to everything they can to match a RR and then is it really "box stock" or is it "all upgrades up to an including what comes in the top kit available".......

Meh, whatever, TT-02 racing is fun local bashing or quasi-wannabe roadie racing. Usually once someone gets a TT platform to really run well, they want to or are ready to move to a more sophisticated class if available.

I just want to get mine to do what I want it to 85% of the time lol

I went with the AW grease in the rear diff and the putty for the front. Honestly I feel the diffs are perfect and don't see any benefit of going to oil diffs unless you need to constantly adjust the diffs. The stock diffs in the TT02R are lighter than the sealed diffs and you can easily get the diff action you want or need with grease and putty. They are also cheap so you can have a couple spares set up with varying amounts of putty in them for different actions.

I've had a similar idea of just having an extra diff ready to go with a heavier grease or putty vs. having to open and "change" the grease which is a mess to do trackside and not ideal.

I have the extra "plastic" parts to make an additional couple diffs however I do not have the additional 4 small silver screws to complete the diff........anyone have a part # available that would contain those screws?

I believe this is what you're after:

Rc 2X8Mm Tapping Screw: 44002 none / Tamiya USA

thank you......appreciate that.....

Weekly local Thursday night carpet races last night........didn't go well with the TT-02.

Got there early and had it pretty dialed in.......was turning 13-14sec laps and the occasional 12.9......that is very competitive for us. When I came back to the pits I noticed the inside of one of my tires needed to be re-glued, so I regaled the tires.......car was never the same and a complete oversteering mess. Through all heats and the Main.

After the races I stayed a few mins to try a few things. Since I have tried everything to make the lowest ride height work (about 5mm front and rear) I needed to try something very different. I raised the rear to the top hole on the lower arms for the CVA mounting and went back out. Totally different car of course, now I was prone to traction rolling BUT I could hustle it around the track for 13-14.5 second laps vs. the fish tailing spin-out machine I had.

Since I have the softest springs in the rear with no spacers I think next week I will first try a medium or large spacer in the rear to firm it up a touch and see where that lands me before I go up a spring rate.

Damn TT-02s......they are like the girl in college you know you shouldn't be with but you call each other when you are drunk and you just cannot stop that behavior......

At least I won with my TLR in the 17.5 2wd Buggy class