- Tamiya TRF201X - Randy Caster - 201 Testing Updates -

Anyone who checks out the 201 thread on RCTech will know I am pretty transparent about my testing. For those who don't check it out, I will copy and paste a few of my submissions so you can follow along with my testing in preparation for the Reedy Race in January. This is a long submission, but should give any readers an idea of what I'm testing. I check on the 201 thread on RCTech daily, so if you have a 201 and have any questions don't hesitate to ask on there!

9/5/11 - Giving my 201 a complete rebuild, almost have it all back together. Have some new setup ideas on the car right now, going for a really smooth/easy to drive setup that lands a little better than my previous setup(s). Rebuilt the transmission and put the new Tamiya ceramic diff balls and carbide thrust balls in, gotta say my diff is as smooth as glass without sanding the rings down. I usually run AE carbide balls because up to this point they were the smoothest diff balls I've used, but the new Tamiya ceramics are just as smooth but should last a lot longer. Really looking forward to the track on Tuesday, excited to see some good results with the new setup.

9/6/11 - It's kind of going in the exact opposite direction of mounting everything down the center of the car, but in my testing today I actually ended up putting weight on the outermost sides of the chassis next to the receiver and ESC. I was having issues with the car tipping over really easily without the weight, but with it the car felt a lot more planted. I have been running the optional chassis but went back to the stock one to generate some extra grip. It is lighter and I think that's what was part of the cause of my unstable car. I have mainly run the 201 with extra weight in the rear of the car but as of late have been shifting the weight up towards the front. Today was the first time I've run it with no added weight in the rear and all up front. The car worked really well with this setup. With the weight in the rear it will want to continue rotating as you are exiting a turn, with the weight up front it is more of a point and shoot feel. As soon as the car was pointed in the direction you needed it to go, you could hammer on the throttle and had plenty of grip exiting the corners. We both tried 1.3mm and 1.4mm front pistons with 30wt oil in our cars. Both of us favored the 1.4mm pistons to the 1.3's. The lighter dampening actually helped make the car less twitchy off center but had more steering overall. A few months back I tried running the 4wd front yellow springs on my 201, and those ended up being the spring of choice today for Jake and I, they felt really good. My setup for the rear end stayed with a yellow spring, 1.3mm piston with 27.5wt oil. Both of us had no lack of steering even with the added rear bite, so you couldn't ask for a better combination.

9/9/11 - I forgot to mention one of the major changes that Jake liked on his car was unthreading the rear shock eyelets 2 turns to give the shock an extra 1mm of length. Once he did that the car went over the bumpy sections of the track much better. That has been the 1 thing on my car that has stayed for a long time, really helps make the car easier to drive.

9/11/11 - Another day of testing is in the books with a club race to top it off. Jake and I hit WCRC again yesteday to try and improve on our times from last Tuesday, gotta say it was a success. I played around with battery position, and changed my rear shock oil/piston combos a total of 5 times, but it was Jake who hit the nail on the head by drilling out 42166 blank pistons into 3 hole #56's that really worked. We started off with 27wt oil, I put 30wt in for my 2'nd qualifier, and both of us ended up with 30wt for the main. I ended up liking my battery in the forward position after playing around with that. Had an awesome turnout with 2wd mod buggies, 2 heats of sportsman mod, and a near full heat of expert mod. Jake qualified 4'th with me in 5'th, and after the dust settled I worked my way up to a 2'nd place finish with Jake right behind me in 3'rd. I am a bit out of practice and a little bummed with myself because I had a decent size lead at one point, but bobbles took that lead away, so because of that it's another full day at the track tomorrow so I can feel more confident in running 5 mins without mistakes. In short, we have both really benefitted from the practice days this week, both of us have the same attitude where if something is working OK we just get comfortable with it. Watching and driving eachother's cars we have ended up making numerous changes and have really gotten both of them going around the track a lot faster.

9/12/11 - Jake and I have been working really well together on the setups, and we seem to like the same feel out of the car, so that really helps. He made a switch to the high bite chassis for Saturday where I stayed with the stock chassis. I know at the beginning of the day he was really happy with his car, but after the mains we drove eachother's cars and I think (not 100% sure) that he was going to switch back to the stock chassis. Even though our setups are almost identical our cars feel very different, and that is due to the electronics. He has a good amount more push brake than I do, he handles it well on the track but I have a really hard time keeping the back of his car in line under the brakes. Also because of the electronics I am able to fit more lead weight at the outsides of the chassis which I feel gives my car a more planted feel where his car has a more nimble feel and changes direction really quickly. Without the added weight on the stock chassis, my car was having issues rolling over in corners or on landings and felt too springy. I am once again heading to WCRC today and have decided to stay away from the big bore shocks for one last testing session to get a couple questions in my head answered. First off I wanted to try running 3mm anti-squat for the main on Saturday, but realized there wasn't space for more than 2mm of washers. I tore the back end down last night, took everything off of the back end of the chassis and cut off the cross piece of the chassis above the pivot mount. That will allow me plenty of room for more anti-squat shims. Without any of the pieces mounted on the chassis, it did have a small amount more flex without that brace on there, but once everything was mounted and bolted down I didn't feel any difference. My baseline today is starting with the 2mm anti-squat to see if I can feel any difference from cutting that brace off. Once the anti-squat is settled I am going to move to my front camber links. I have 3mm on the inside of the link which makes the car fairly aggressive off center but has really good steering. Because of the aggressive feel I ended up dialing in 10% expo in my steering. I'm hoping that I can lower that down to at least 2mm and get the car even easier to drive into the corners without sacrificing any steering. (My car has a TON of steering as well, so there is room to give some of it back)

9/13/11 - Alright, time for an update from testing yesterday. First off is the 3mm of anti-squat. I have been running 2mm but basically just wanted to see how 3mm would feel around the track, the only thing I knew was from my on-road racing and that has taught me more anti-squat = more rotation in the corners. Sure enough the car rotated extremely well in the hairpins, but this also makes it a bit harder to drive in the higher speed corners where you need the car to stay a bit more planted in the rear end. One thing that it did help with was give the car a little extra push off the lip of jumps. I noticed the car would jump further than with 2mm of anti-squat. There is a large triple on the track that I like cutting the corner fairly close on, however I end up casing it most of the time if I take that line. With the 3mm anti-squat I was able to cut the corner fairly close and still make the jump consistently. I still have more testing I want to do with the added anti-squat, but because it did make the car a bit harder to drive, I went back down to 2mm. Next time I am going to try running 3mm, but also lowering all of my camber links on the inside by .5mm in the rear and 1mm in the front. That should make the car a bit less aggressive to hopefully mellow out the added anti-squat. If I can get the car easier to drive with the 3mm there, I will be running it. The second test ended up being with the big bore shocks. Although I had time to change springs once, I didn't have enough time to play with different oil and piston combinations. I ended up starting off with what the Losi guys will generally run on the indoor tracks which is 55 pistons and 27.5 wt oil on all 4 corners. I started with Kyosho red rear springs & pink front springs. The car felt a bit soft with that setup so I switched to a yellow rear spring which is 1 step down from the stiffest they offer. The car still felt softer all around than with my Tamiya shocks & yellow springs. Because it was softer, I couldn't get the car to jump like I wanted it to. That is basically where the negative points end though. Even with the car feeling softer, it bottomed out less on landings and over bumps. There is 1 bump on the front straight that has been giving me issues for the past week, it is a high speed area and when you hit it just right, it kicks the back end of your car over and smacks the rear shock tower right into the face of a jump... hard. I've gone through 3 pairs of wing mounts and 3 wings because of it. With the big bore shocks, I saw my car hitting the bump numerous times, but it kicked the back end of the car up a couple inches and the car kept going. The big bores really handled bumps better than anything I've tried so far with the stock shocks. I have also had issues with my car being a bit hard to correct on sideways landings or when it gets out of shape. One thing I noticed right off with the big bore shocks is that I could drive the car right out of those situations on power without losing much time at all. Now I said the shocks felt soft around the track, so I called one of my Kyosho buddies who is a setup expert to get a little feedback from him. It turns out that I was running my rear springs 3 steps heavier then the Kyosho guys generally do, and the front springs 1 step softer. I was going off of a setup sheet from the Reedy Race last year when I chose my springs, but things have changed quite a bit with their setups since then. He gave me a few pointers on how to get the softer springs working well and jumping like they should, and now I have some things to try next time at the track. I can see these changes making the car easier to drive with a softer more plush feel around the track, which hopefully will bring the 3mm of anti-squat back into play as well.

10/4/11 - Inline axles and 25* caster blocks will give you the most initial/turn in steering. 30* caster blocks and the axles in the trailing position should give you the most mid-exit steering.

10/11/11 - Ran at OCRC today, they have a really fun layout in right now. No big jumps on the track, just a technical layout that flows really well. Track has a good amount less grip than WCRC so I was struggling a bit with rear bite, but managed to change a few things and get a bit more. Tried the XA block for a little more inner toe and it actually helped give the car a little extra traction. My car was a little soft and the extra inboard toe helped to stiffen it up just a hair, I also added a 1mm shim under the inner camber link ballstuds to get the rear end to roll a little less as well. Those changes seemed to help get the car a little more forward bite out of corners. All of the weight in my car is towards the front and this layout exploited that a bit, the nose felt heavy over a lot of the jumps, need to work on that without adding any weight to the rear end. My hopes are that getting the car really good on a lower grip track will help make it easier to drive at WC. My car still has a TON of steering, so I'm not worried about having any pushing issues.

10/12/11
Raced at OCRC last night against an absolutely stacked field, turned out to be the wednesday night nationals with 16 2wd mod entries. Truhe, Numan, Root, Pavidis, Hodapp, Castellano, Jarosz and plenty of fast locals were racing, it was a really good night to see how the 201 stacked up. I managed to qualify 4'th in the A and after a couple laps had worked my way up to 2'nd behind Truhe. Unfortunately it didn't last long and as I got a comfortable hold on 2'nd place I tried pushing the car harder and caught my right front on a pipe at decent speed and knocked the ball cup off. Turnmarshall just pulled the car so I thought it broke the hub, was a little disappointed to see it was such a quick fix and could have still been in the race but oh well.

Anyway I was really happy with the progress I made on the 201 at that track in short time. Ran practice on Tuesday and showed up Wednesday night with enough time to run one pack before racing. OCRC is a lower bite track than WCRC where the Reedy will be held, so I had to lock in the rear of my car a little more to make it easier to drive. I only made changes on the rear end of the car and left the front end the same so I still have plenty of steering. Excited to see how the setup will feel at WCRC, should be able to really push the car there without having to worry about the back end coming around.

On another note, I don't think I'll be taking the big bore shocks off anytime soon. I didn't change them once on Tuesday or Wednesday and they felt great the entire time. I was going to take them off and test back to back against the TRF shocks but there really just isn't any need to. My car was having a bouncing problem with the stock shocks and it is basically gone now. They absorb hard impacts much better than the stock shocks and go over bumps much better. I'll get some pictures of what I did to fit the Kyosho shocks to the car for anyone who wants to pick them up and try them out.

10/22/2011
Some pics of my updated weight placement. Just under 1 oz on the right side, just under 3/4 oz on the left side, and 1/2 oz in the nose above the bulkhead. The change I made was taking the 1 oz of weight out of the front of the battery area, and placing 3/4 oz right in front of the servo. Trying to get the front end working a little better and getting a little more steering out of the car. I am expecting that even with slightly less weight it will have more impact on the car being placed further forward.

11/06/2011
Keeping you guys up to date with my electronics and weight layout.

After trying the Orion R10 Pro ESC I ended up purchasing one along with the Orion 7.5 motor. I am running this with the Dustin Evans nats winning setup and it's just incredible how smooth it is, but at the same time how much power it has. I am running this with the brake EPA set at 55%, 10% negative expo on throttle, 15% negative expo on brakes, and the timing retarded 1 line on the motor.

As you can see I am running a shorty lipo, which gives the car a completely different feel. Compared to a full size (full weight) lipo, the car jumps and lands MUCH better. I went to a full size lipo in one of my qualifiers last Wednesday and ended up casing the landing of the jumps over and over again.

I played with battery and weight placement with the shorty pack a lot, after running it in all sorts of positions, I found that I like it centered in the tray with a 20 gram weight behind it. The capacitors for the R10 are also positioned in the rear foam block, but they don't weigh much so won't really affect handling any.

The feel of the car also vastly changes with the shorty pack. In this placement, the car pushes a lot more than with a full pack, however, it has a good amount more rear end grip, which allows the car to be driven a lot harder, and basically I just use more brakes to allow the car to steer. It does take a bit of getting used to because the car is a lot twitchier with the lower weight, I'm going to play around a bit with my front camber links, lowering them on the inner ballstud should take a little twitchiness out of the car, and give a bit more steering overall.

I've changed my front shock oil from 27.5 down to 25 to try to get some of the steering back without having to use the brakes as much. Heading to WCRC in a little bit to try this out.

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