Kn7671 thanks for the report. Sad news. more below.
Traction med on rubber, medium-low on foam, 90 F track temp, cool
Jeff had the tracks timer calling out lap times. (Nitro Nats are coming next week). I got a few runs in on a fairly clean track that had two other cars on it today.
Practice lap times were immediately as fast as the fastest I had last race. Low 19's to 19.0 was the best.
I traction rolled the car. This was my first ever. I turned slightly left then right onto a highspeed sweeper and it rolled faster than I could take any corrective action. This really was a driver error as I made the little back and forth move too fast. I really don't need that little left move either as it is not a motorcycle. I had no troubles elsewhere with smooth radio movements. This shows that I am getting good traction from my rubber tires on a mediocre day for foams. There was a 1/10 nitro and 1/8th nitro turning slower laps than me.
I tried 3 tire types.
Sorex 32-these are smoother in the drift, but were a couple tenths slower today. This was a really old set.
Takeoff RP30's these had good grip early but it went away suddenly after four laps. This indicates that they are too soft.
I ran my caster block pivots without my locktite fix
(page 1 of the thread) after my recent bearing overhaul. On the RP30's I tapped a board hard sideways from the tires just letting go after they got too hot. It tore out the bottom screw out of the caster block. My thought was maybe it was not needed with the more flexible material and slightly larger screws. I still recommend it after this incident. I had no trouble up there for a month of hard use with the locktite applied. It does take heat from a soldering iron to dissasemble it for service.
In a similar vein the need for a shim added to the crush spacer on the drive axles has not materialized. Because the plastic is softer now the bearings waller out the holes and become more sloppy in the steering blocks with use. You cannot remove this by tightening the wheels harder.
I found some rubber sealed bearings with grease for the wheels at the hobby shop. I found some new metal shield bearing with grease for the outdrives. This is not so ideal. You really need grease and rubber seals here, then the outdrive bearings last forever.
Grease or Oil
A bearing with grease will make a channel in the grease on first use and the balls will run on an oily film. The grease just does a much better job of staying in the bearing, to provide this lubrication, and of sealing the dirt out
. This is what I recommend for general use on the car, rubber seals with grease. That 3.5 motor spins really fast, it needs the oil to keep from exploding the ball retainer inside the bearing. This is the only bearing in the car, I would use oil on by preference.
If you are going to a big race you might shave a few.01 s off your first heats wtih oil and metal shields, but I estimate by heat 3 or 4, a few of the bearings will have grit in them , by the third or fourth session all the bearings will be scored up and ruined by the grit. I have tested this. Yes the car will still work, but will be slower than if you had used grease at the beginning.
I am sad to see the kits coming with oil in the bearings.