Rock Force Setup and Testing

[dkingston]

I did some initial testing this evening as to motor, battery, pinion and gearing.

Here is the setup:
HS Gearset/23T Pinion = 56.09:1 Gear Ratio
55T Integy Motor
3S 1500 Cheap Generic Lipo
Mamba Max with Castle BEC
Hobbico CS170 for Steering
Hobbico CS170 for Dig
Ambient Temp: 39 Degrees

What I was intending to discover was a baseline setup that would provide decent wheel speed and reasonable temps for the motor speedo and batts.

Here is what I found:
All temps measured with an Exergen DX501 temp gun.
I ran the pack until the voltage cutoff kicked in (the only thing I didn't do was watch the time DOH)
The highest the motor temped was 82 degrees
The highest the heat sink on the speedo measured was 42 degrees
The highest the axles measured was 85 degrees

I have believed that the temp issues that some had encountered were more to do with over-gearing the motor attempting to regain wheelspeed. The setup used was a more conventional one that I would expect to give great results from an efficiency standpoint. I was not disappointed.

Trying to establish a runtime in hindsight would be silly. It seemed like a reasonable amount of time to run but more testing will be done to get accurate timings.

Dig Testing:
I was constantly going in and out with the dig, trying to get it to respond as it would in a normal comp situation.

Using the CS170 was seemingly overkill initially. After using it I was satisfied that the additional torque is handy to have.

There were a couple of times that disengaging the dig it didn't just come out. A little blip of the throttle would bring it right out. This happend a few times initially and after going back and adjusting the spring tension on the lever it seemed to get considerably better.

The dig worked pretty well on power. I tried using it like I did with the berg: on power, in and out. It performed very well, actually better in engaging and disengaging on power than not.

I believe that replacing the springs with about 3/16" of fuel tubing with small washers at each end, will provide much more consistent functionality. I will try to get to this later in the weekend.

___________________________


I will be comping with the Rock Force on Saturday. Since it has been a while since I have been on the rocks, my finish may or may not reflect well on the rig ;) . There will be several drivers there who will get the chance to try it out. Hopefully, they will give some feedback on here as well.


- David

[EeePee]

Right on.

[killjoyken]

Perfect! This is exactly the kind of test we need. Good luck at the comp.

I've been planning the same thing for the dig setup. I've got a 200oz Airtronics 94361 for my dig. After reading John's issues with releasing the dig from lock I was also planning on either using fuel tubing or even a direct linkage like my DNA dig. Did you use any grease on the pins and metal lock plate? The instructions don't call for it, but it may help with a smoother disengagement.

The high speed gears are nice, aren't they?

[dkingston]

Whew, just returned from the comp and have several things swimming around in my head.

I think my assessment from last evening about the gearing/motor/temp issues were correct. The motor never temped over 92 degrees which was nearly identical to every Berg and Bully rig I temped today. (I think they must believe I was crazy, wanting to temp their motors!)

There was no real opportunity to time my runs today to see how the battery life was. I truly believe that the lack of runtime was a function of the gearing.

The Dig
I experienced some hesitation disengaging the dig on a few occasions in my fist run. Between courses, I decided to take about 3/16" of fuel tubing and put it in place of the springs. PRESTO, things were immediately better. Not quite perfect yet but from what others were saying at the comp it was as good if not better than any other mechanical dig currently available.

My satisfaction with the performance at this point is pretty high. Individual tweaking and adjusting will be necessary on your rigs but I highly recommend fuel tubing in place of the springs.

The only real bad news on the dig was something that happened that was totally my fault. Since putting it in last night, I didn't take the time to trim the excess servo arm that was left after the point where the linkage mounts. While goofing around, jumping through a gate, I landed and clipped the end of the servo arm. The arm broke right above the linkage mount. :-( That ended the testing for the day.

The Shocks
The shocks do an incredible job of dampening the suspension. Maybe too good in fact! Running 30wt oil is too heavy, especially in the winter due to the temps affecting the effective viscosity. EeePee is running (I believe) 15 to 20 wt in his. I think for now that is probably the way to go.

The Suspension in General
Overall, the suspension cycles pretty well. There is some axle swing that I think can be adjusted out, to a certain point. I will be playing with some setups for this. Like I think I mentioned earlier, I am not running my righ cinched down. I like the 3" skid clearance. There are a couple of us that are working on Panhard tweaks for running the Rock Force fully extended. I think this will help the overall handling.

Where do I go from here?
I know I am a tad biased about the Rock Force but I have tried to be as honest in these posts as possible. To say that I am really happy with this rig would be an understatement. Now it is time for me to just spend some time with the Rock Force on the rocks, getting more familiar with the rig. Work on setups will be a pretty high priority as well.

As I find more things I will post them here. If any of you come up with any setup tips, please post them here as well!


- David

[dkingston]

Originally Posted by killjoyken

Perfect! This is exactly the kind of test we need. Good luck at the comp.

I've been planning the same thing for the dig setup. I've got a 200oz Airtronics 94361 for my dig. After reading John's issues with releasing the dig from lock I was also planning on either using fuel tubing or even a direct linkage like my DNA dig. Did you use any grease on the pins and metal lock plate? The instructions don't call for it, but it may help with a smoother disengagement.

The high speed gears are nice, aren't they?

Ken

The fuel tubing is DIALED, go for it. Grease won't help in my opinion. Give that a try and I think you will be happy. The dig is a pretty slick setup.

The Highspeed gearset are very nice. The "dewalt" noise appears to be gone and there seems to be less heat in the axles as well.

Let us know how yours goes!


- David

[EeePee]

Originally Posted by dkingston

EeePee is running (I believe) 15 to 20 wt in his. I think for now that is probably the way to go.

Yep, you're correct. 15 in front, 20 in back. I put the 20 in back just because the shocks are laid down a little compared to the front. If I had 17.5, I'd go that route probably. And I'm using Losi oil.

And I didn't modify the stock piston as the instruction say to.

[Racer4Life]

DK....very honest write-up!!

[Reflection]

Originally Posted by dkingston

The Dig
I experienced some hesitation disengaging the dig on a few occasions in my fist run. Between courses, I decided to take about 3/16" of fuel tubing and put it in place of the springs. PRESTO, things were immediately better. Not quite perfect yet but from what others were saying at the comp it was as good if not better than any other mechanical dig currently available.

Be nice to somehow have the freewheel option. I'm glad to see your getting the dig working better though.

Originally Posted by dkingston

The Shocks
The shocks do an incredible job of dampening the suspension. Maybe too good in fact! Running 30wt oil is too heavy, especially in the winter due to the temps affecting the effective viscosity. EeePee is running (I believe) 15 to 20 wt in his. I think for now that is probably the way to go.

I've always liked my Kyosho shocks. Even the plastic bodied shocks I have still work like a champ after years of abuse. Are the pistons in these shocks the same as the Twin/Mad pistons? Or do they have holes in place of the flats?

Originally Posted by dkingston

The Suspension in General
Overall, the suspension cycles pretty well. There is some axle swing that I think can be adjusted out, to a certain point. I will be playing with some setups for this. Like I think I mentioned earlier, I am not running my righ cinched down. I like the 3" skid clearance. There are a couple of us that are working on Panhard tweaks for running the Rock Force fully extended. I think this will help the overall handling.

Be hard to get axle swing out without magical adjusto links. I'm interested to see what you come up with. Double triangulated is best for that though. If a guy is used to having a certain amount of axle swing or steer,you can use it to your benefit at times.....just have to know your rig.

[EeePee]

Originally Posted by raptorman57

Or do they have holes in place of the flats?

No holes, flats on a side. The instructions tell you to file another flat on the other side.

[roborg5000]

Defiantly an improvement from the last time you brought it

[dkingston]

Raptorman, the freewheel option is there. I just didn't have enough time last night to program the radio to play with it.

[Reflection]

Originally Posted by dkingston

Raptorman, the freewheel option is there. I just didn't have enough time last night to program the radio to play with it.

How do you get worm gears to free wheel?

[EeePee]

Originally Posted by raptorman57

How do you get worm gears to free wheel?

Disconnect the axle, from the gears.

[dkingston]

Originally Posted by raptorman57

How do you get worm gears to free wheel?

The worm spur gear spins free on the shaft. When the shift fork leaves 4wd and before it locks there is a position that allows for freewheel.

This dig is pretty clever in its design!


- David

[Dewmerz]

Sounds like you had great results today. Ken helped me out with the needed part numbers so I should have a set of axles/trans in the next week or so with HS worm gears and dig. We're just waiting for the order to show up at the LHS.

[killjoyken]

Well, I also got a bit of testing in today and the RF performed great. In fact, the RF outperformed my GC-1 on a number of climbs and even made one my GC-1 couldn't. In the defense of the GC-1, I was running some well worn Panthers that weren't biting like they used to. But it wasn't just that it was making the lines, but how easily it was doing it. Switching back to Claws on 8-holes was a big improvement over the Badlands on Epics. The rig likes to stay planted and likes the lower height of the Claws. The only downside was that the axles were getting hung up a little more than before. I need to work on smoothing them out some more.

I lost some wheelspeed with the new gear ratio but the motor never stalled and worked well for finesse climbs. Right now I think I'm sticking with this link and shock setup. I've got 2 weeks off to get some more seat time before the next comp on the 4th so I'll have a full report then.

For now I'm still amazed that I made it through a full pack without once wanting to check the rig off the mountain.

David, thanks for the fuel tubing tip. I won't bother with the springs.

I forgot to add: for the guys using the stock shocks make sure you follow the instructions on filing the pistons. It seems that everyone who doesn't has the same problem with the shocks reacting too slow.

[dkingston]

Originally Posted by Dewmerz

Sounds like you had great results today. Ken helped me out with the needed part numbers so I should have a set of axles/trans in the next week or so with HS worm gears and dig. We're just waiting for the order to show up at the LHS.

AWESOME! Ironically, I just got off the phone with Steve from Kyosho asking about the diagrams and manual. Looks like they will be available around Monday.


- David

[EeePee]

Originally Posted by killjoyken

It seems that everyone who doesn't has the same problem with the shocks reacting too slow.

Not with lightweight oil I don't.

[dkingston]

Originally Posted by killjoyken

Well, I also got a bit of testing in today and the RF performed great. In fact, the RF outperformed my GC-1 on a number of climbs and even made one my GC-1 couldn't. In the defense of the GC-1, I was running some well worn Panthers that weren't biting like they used to. But it wasn't just that it was making the lines, but how easily it was doing it. Switching back to Claws on 8-holes was a big improvement over the Badlands on Epics. The rig likes to stay planted and likes the lower height of the Claws. The only downside was that the axles were getting hung up a little more than before. I need to work on smoothing them out some more.

I lost some wheelspeed with the new gear ratio but the motor never stalled and worked well for finesse climbs. Right now I think I'm sticking with this link and shock setup. I've got 2 weeks off to get some more seat time before the next comp on the 4th so I'll have a full report then.

For now I'm still amazed that I made it through a full pack without once wanting to check the rig off the mountain.

David, thanks for the fuel tubing tip. I won't bother with the springs.

I forgot to add: for the guys using the stock shocks make sure you follow the instructions on filing the pistons. It seems that everyone who doesn't has the same problem with the shocks reacting too slow.

Great to hear, Ken!


- David

[killjoyken]

Originally Posted by EeePee

Not with lightweight oil I don't.

But you said:

Originally Posted by EeePee

The suspension is very smooth. I have only 15 weight in the front shocks, and 20 weight in the back shocks. But with the piston being the way it is, the rebound and compression dampening is still pretty slow. And with the front shocks being vertically mounted, they'll have a more direct effect than a set of laid down shocks will.

:-P