My first club race was a huge success with the Yokomo YRF 001 chassis.
Being absent for 3-4 months due to a cycling accident, I was unsure how this chassis would stack up against the competition. The F1 competition ranges from Kyosho, Tamiya, to name a few. However, I was the lone Yokomo driver. The weekend before, I managed to squeak in a few laps to find a setup that works for the track layout. Everything was going well, until I had a freak accident which snapped the carbon fiber piece mounting the center shock to the motor bulkhead.
Anyway, I only had about 20 laps to figure out what direction to go with chassis setup. I ended up changing a few things, from what I gathered from the short track time.
A- The stock servo mounting position seems to make the YRF 001 corner transitioning a little sluggish (Not good for tight, twisty tracks). This is due to the forward mounted servo placing more weight on the front suspension.This would be good to use for low traction situations, and be good for more open flowing tracks, however, tight and twisty tracks should utilize the optional rearward servo position. This makes the steering more reactive (less weight on the front suspension arms, placing the weight more rearward) and results in quicker corner to corner transitions. Another thing, when running the stock servo position the car tends to "dig" too much when entering into long sweeping corners. This makes it difficult to carry a lot of speed though the corner. I switched over to the optional rearward servo mounting position and it cured this problem. Keep in mind, you don't really need to buy this optional part right away. Every track is different, so test out what works for you. This was the only upgrade I made to the chassis and it worked out perfectly.
B - I change the shock piston to three hole and bumped up the oil to 1000 Yokomo oil, or 1000 Kyosho. If you're wondering its 100wt oil
. I also changed the side damper to Kyosho 650 (60wt) and side springs to Yokomo copper. I think the stock springs are a decent starting point for medium to long tracks with a few chicanes. My local track is extremely tight and twisty with lots of chicanes, so it was important to get the car to transition quickly.
C- I opted for ceramic differential balls instead of the standard kit balls. Sanded the differential rings with 600 grit paper, and added an additional 2 conical spring washers to the already one differential spring washer. The three
spring washer setup made the differential SO SO SO smooth, like....crazy smooth. It's important to keep a close eye on the rear axle clamping hub. It tends not to hold on so well and I found out after a few races the axle had some side to side play. Which means the clamping hub is slipping off the smooth carbon axle surface. I might try and scuff up the surface a little, or add a thing layer of rubber glue to add some additional gripping power. I also balanced the rear pod just for the heck of it (You don't really have to do it). I placed 5 grams on the motor side.
D- Make sure the roll damper set screw holding the ball end onto the shaft isn't touching the chassis brace. I found the chassis roll was affected by this set screw touching the chassis brace. All I did was twist the ball end 180 degrees so now it faces up. Problem solved.
I also increased the castor to 4.6 degrees.
I learned quite a bit considering the lack of track time.
Race day went well. The outside temperatures were hovering around 12-15 degrees Celsius. A little on the chilly side, but we were running 21.5 foams.
I trued down the rears to 51.00 mm and fronts to 50.00 mm. This gave me 3.8 rear ride height and 3.6 mm front ride height. Note : I was using the 2 mm axle spacer for the smaller diameter tires. I also took, out one spacer from all four corners on the front suspension. This allowed me to run smaller front tires. However, you have to readjust the set screws accordingly. For each 1 mm spacer taken out, you must adjust all the set screws by 1 mm. The bottom set screws must be decreased by 1 mm, whereas the top set screws must be increased by 1 mm. Remember to adjust them all. If you don't then the carbon arms will not function properly. There must be an easier way of changing ride heights, I haven't bothered looking further into this. I assume, the kingpin spacers will have some effect in ride height change. Just haven't bothered.
Also, make sure your chassis is balanced side to side. An ill handling car starts will an unbalanced chassis. So, first and foremost, try and balance the chassis.
Enough talk... The cars on track performance was magical for its first time out. I TQ'ed on the first run, being 0.300 tenths faster than the next guy. I might add, this guy has been running his Kyosho for 5-6 months prior and has access to a Kyosho factory driver setup wisdom
. The car was fast, consistent and so easy to drive. I was able to drive the car up on the raised racing curbs with confidence, and the car cut the corners with ease. Basically it was on rails. The a-main was 8 minute run and managed to click off extremely fast and consistent laps and finished 3 laps ahead of 2nd place.
The most important thing for me was using the right amount of traction compound on the front tires to dial in or out steering. The rear was locked in for traction.
I hope this helps, and I used Yokomo's high nose body. Nice body, and great handling characteristics.