crusadores

HWA224,

you are using the hex conversion, right? The front is noticeably wider than the rear. That reduces front grip, slows steering response and induces a bit of high-speed understeer. On the contrary a wider width rear increases rear grip and high speed steering and reduces traction rolling.

Hmm... I believe i was the first to use the "octopus effect" [:-] allegory. I can vividly remember fighting the monster while driving in a very low traction racetrack. The retarded steering response was extreme!

Hwa224

Dimblum,

Thanks. Everything checks out for the one-way. If anything the motor is running hotter because the spur/pinion mesh isn't all that I thought it was. The spur might be wearing down and I can't get it to mesh with the pinion in the same way that I had it at some point before. (I use my own "method" for setting the mesh, as I have never found any consistency or reliability in the paper method.)

The last I checked, the diffs were fine. The slipper is fine. I'll need to check on the belt tension. I never considered checking to see if the belt tensions on the two belts are equal.

Anyway, for the Dirt Hawgs, I like the camber on the rears slightly positive. But now that I have the balding stock tires back on, coupled with the adapters and DF03 wheels. I'll consider readjusting the rears.I'll consider the shock positions too. But right now I have the car handling in a way that it fits my driving style and tastes. The only thing again that I don't like is the 2 wheel braking.

-

crusadore,

I really like the DF03 wheels. But it's true. Especially when you look at the DB01 from behind, you can tell that the front wheels are stanced wider than what's stock. But, honestly, it hasn't effected the handling in a bad way as far as I see, or not in a way that one couldn't tune for. And for the stance alone, IMO, the DB01 looks so much better.

ElectricGuy007

If your racing I highly recommend a front one way. It will make the car handle like a 2wd off throttle.
You only have 4wd when going forward. The center one-way does something similar.
But it's still a preference thing. Some people like front one-ways others dont.
You just have to drive with one and see if you like it or not. I cut seconds off my lap times running a front one-way.

Hwa224

Nice! I have had the center one-way for some time now. It seems to unleash some sort of rotational torque that didn't exist without the one-way, which is why I've been having to research on suspension tuning and so on, to cope for that extra power. But I like it, even though I'm just a basher and probably have had no real need to get one.

-
-

Pro-line sent me an email about their Road Rage tires for the buggy fronts. Accordingly, they say it is discontinued and that poor sales did not justify production costs. That's too bad. But maybe not too bad considering that Schumacher makes a good enough line of on-road tires for 1/10 buggies. Go here:

http://www.racing-cars.com/sp/catego...oad_Tyres.html

The RT1 Road And Track (Green) tires look great for pavement. The RT3 have a chevron appearance to it, which makes me think it would be a decent all terrain tire. I'll check later to see if that website can ship to the U.S..

Legdog

Hwa224

nice find on the Schumacher road tires! Thanks for posting that link .

Eman77

Hey, I've been to that site before. Used to own a Bosscat (4WD), ran it with a 19T and then a MM 5700 combo.

I ran the RT1s on street pavement/bashing, and they seemed ok. Not sure the tire was soft enough for me though, don't recall grip being excellent, but not bad either. Then again, I complained about the Dirt Hawgs, which you love, so maybe we just have different views on tires. Keep that in mind.

From what I recall, the tires lasted decently, so that was good.

You sure seem to be going through tires fast though, you run yours a lot more than me.

Hwa224

I run my DB01 like a smoker takes cigarette breaks. It's nice to have so many good "bashing spots" available outside of my door and even at work where I have a stretch of 500 ft of empty parking space to have fun with.

The stock tires are now almost completely bald. In fact they're shiny smooth for most of the width of the tread. I've been using them to practice drifting.

The set of Schumacher RT1s shipped to the US will cost 31 dollars, which is not a bad price.I'd buy another set of chrome spoked wheels just for the sake of getting the Schumachers on them. ButI have an extra set of black dish wheels that I think will end up going unused, which is 12 dollars I could have used to buy something else. Any suggestion as to what I should do with them? After the chrome spoked wheels, I don't like the plastic dishes.

For now I'm going to bake off or maybe just tear off the Dirt Hawgs from the Baldre's dish wheels, and then mount the tires on the chromes I have and see how that goes.

Eman77

I guess save the new dish wheels you have, in case you need them in a pinch.

For the chrome spoked wheels you have, did they come with tires mounted? Did you bake them off?

Hwa224

Hi Legdog,

Tires came in preglued. The glue was adequate but not very strong and I was able to "crack" the tires off. I prefer it that way - to use a glue that is strong enough for running RCs but weak enough so that it sucumbs to the pressure of a strong finger/hand.

OTOH, I used a slow dry loctite CA glue to glue my Dirt Hawgs and I had to bake them off. (Preheated oven to 350 f; wrapped each wheel in tin foil and then placed them on a bent up, used tin tray. And placed in oven for 20 minutes, etc.. No bad smell as I was afraid of. And I used an oven mit and moiste towel to handle the rest. Easy.)

- BTW, how's your Durga doing lately? Any mods in the works?

Legdog

Hi Hwa224,

haha I like your turn of phrase "like a smoker takes cigarette breaks". I will have to remember that one.

I've been meaning to ask you, when you baked the tires off were you afraid of weakening the rims with the heat? I suppose 350F for 20 minutes wouldn't cause too much damage...

No real mods in mind at the moment. Ijust did a rebuild to clean it out and Ihad to fashion a bush to fix one of the belt cover screw holes which I bore-out carelessly (and eccentrically) when attempting to remove a stripped-out screw. I used a piece of aluminium tube to do the job which proved to be quite an effort and was the first time I had done anything like it (carefully drilling tapping etc.).

Also just experimenting with differnt grades of damper oil. Curiously I found that the soft Tamiya oil that came with the kit is in fact thicker than the 40 and 50 grade of Losi oil that I purhcased recently. I expected it to be thinner... Unless of course Iam seeing this the wrong way and you may be able to confirm but, Iwould have expected the thicker the oil the harder the damper?...

I also recently purchased Atomic Carbon shock towers to go with my TRF dampers but haven't installed them yet as Iintend to sand and CA glue them before I do. All of the how-to guides on the web illustrate doing this manually with some wet and dry but I am considering using a Dremel to make it a quicker job...

On the subject of rebuilding I still find adjusting the diff tensions the trickiest part of the job. I have attempted the Dimblum advocated method as is guided in the instruction manual but still find the diff too loose once you have the battery in and the wheels on the buggy. So what Ihave did was to lift the front when tightening the rear diff and tighten until it just starts to grab (I mean the car starts moving forward) and did the opposite for the front (raised the rear) and then checked the tension by holding one of the wheels while turning the other. It seems to work ok Ithink, after some further minor tweeks to the tension. I also used this method for the slipper, that is tightening it until the car starts moving forward (not lifted).

Other than that just trying to get the thing dialed as sweetly as possible to see what it is capable of and practicing taking it off jumps in the process...

Legdog

One other thing Iwould like to confirm if anyone cares to answer, what are the suggested camber angles for just general bashing around on the road? I have searched this and other threads and am still a little confused on this point...

Hwa224

I was worried about warping the wheels too. But they just get a nice toasty hot when you take it out. But it's recommended that you let the wheels cool a little before you remove the tires. But it seems to be important to wrap the wheels in foil.

I had Losi 40WT shock oil and I started with that. But recently went to the stock. I had always assumed that the Tamiya was going to be thinner. But it's much thicker. Some people say that Tamiya rating = Losi wt * .1. So the 900 Tamiya shock oil = 90 wt Losi, roughly. I doubt that's accurate but in any case it's thicker.

According to Tamiya the rating of 1 is what the viscosity of water is. The clear shock oil that Tamiya gives is 900.

I'm still trying to figure the suspension out, My car is doing a lot of flip overs and still does now that the Dirt Hawgs are back on. My rears were slighly negative camber. And now I'm going to get them to slightly positive again in the hope that doing so will lessen the traction the rears have in a turn, which would allow them to slide out rather than anchor into the ground. And this way my RC won't flip over so much.

My DB01 never flipped over really even with the taller Dirt Hawgs before I got the one-way. And now I got to try to compensate for it.

Eman77

I just have it set to whatever the kit manual suggested for the tie-rod lengths. Stock works fine for me. I'm running proline calibers, running mostly in the dirt. I don't have flipping over issues, so I haven't found a need to muck with that stuff.

Legdog

Thanks for the feedback guys. I will probably set the camber to neutral or slightly positive to allow for a little slide as you suggest Hwa224. My stock tyres are becomming bald which I actually dont mind as they will be more suitable for street usage. In the mean time I'm going to order a set of RT1s.

Strange to hear your car is still flipping Hwa224. I suspect as I'm sure you do it is probably a combination of things that is; surplus of wind-up caused by the one-way (on this point Iwanted to ask if you had tried loosening your diffs to allow for some of it to escape?) and damper set-up I notice you prefer stiffer/ higher settings which makes sense since you are doing a bit of bashing but have you tried softer settings and bring the car down lower? Thats my guess but there is a good chance Iam completely wrong...

Hwa224

Haha. I just noticed I mistook the author of post 1653. - Sorry.

Atomic shock towers? They do look different from the stock?Do they look cooler? I've read that they can be a bit too tough in that in a bad crash situation they won't break but the next weakest link in the chain, the diff covers, would break.

Tamiya are releasing carbon shock towers of their own, for the DB01, fronts and rears, soon.

New item #s:

54385 DB01 Carbon Damper Stay (Front)
54386 DB01 Carbon Damper Stay (Rear)

-

About the diffs, hmm, when I built the diffs, I used the Tamiya recommendation, that is, to hold both shafts in place and tighten until the pulley gear couldn't be turned. I didn't tighten any more than that.

After running the DB01 for the first few times and knowing about how ball diffs inevitably loosen for the first few runs, the diffs did loosen and I readjusted them by popping off one of the tie rods to get to the left rear wheel outshaft and front right wheel outshaft screws. I held the spur and one wheel firmly in place and tightened until I wasn't able to move the other wheel, and not more. The check to see if the diffs are too tight is checking to see if the wheels turn in the opposite directions from each other when you spin any one of them. If they both spin in the same direction the diff is too tight. ~ I haven't had a problem with the diffs at all after the first readjustment. I never worry about them. The only things I worry about on my DB01 are 1) the wing. 2) the body. 3) the temp of the motor. 4) the dogbones. 5) the spur gear. (in that order of urgency).

-

Legdog,

"Windup" would be what an RC 4x4 gets without the one-way. It's the push-pull binding that goes on when the wheels of one axle can't spin or rotate indepedently from the wheels of the other axle but which need to in a turn situation considering that the wheels are covering different distances and will need to spin at different rates. That's how I understand it. With the one-way, the windup there doesn't exist off-throttle.

Great job on getting the Schumachers! Tell us how you like them. I'm probably not going to get them until the present Dirt Hawgs and wheels wear or break.

I'm thinking of buying a new brushless - an LPR Vector K4 6.5t, which outputs 5200 ? kv instead. Thinking about it.

BTW, my DB01 would run better with the spacers removed and everything lowered. It does in fact. I like spacers because they're so easy to deal with.But I need the spacers by default, because without them my Db01 would get destroyed in my back yard. I'm a backyard basher and that means I need to preserve maximum ride height. The trick for me is to get the best handling with that ride height.

Anyway, I did a quick little run at a park tonight while doing a grocery run... and I didn't flip over once. But that's purely because the pavement was wet. The DB01's corners were still dipping down during a turn. I now have the rear shocks mounted on the lower outermost position, and I have springs taken from other shocks that I had that are considerably stiffer and I still see the DB01 dip a lot turing a turn. If I turn left, I can see the rear right dipping, and so on. I'm sure if the pavement wasn't wet the DB01 would have landed on its lid a half-dozen times today. It slaloms nice enough, though, at midspeed.

Eman77

Good to hear that they come off easy. I really don't like the tires they come with, so I might order another set and remove if it's that easy. I didn't try removal with my last set. I really like the wheels though.

I know you called me Legdog, but that's ok. I know he spoke to what he'll upgrade, so I will too.

As for my planned upgrades, I'm not sure I have any yet. I've got a few already: the hex conversion, slipper clutch, 501x diff joints and plates, upgraded diff balls, thrust bearings, diff grease. But nothing new planned, barring any tragic accidents. Admittedly though, I have barely run it this year. Been playing with other RCs for a bit instead. Gotta fit the Durga into the rotation.

Hwa224

^ DB01 running is a happy DB01. But clean it's happy too. So either way it works, I think since, IMO, Durgas are nice-lookers.

I have honestly read through this entire thread perhaps 1 and 1/2 times, reading up on everything I could.And I've now had the center one-way in for about month. So let me add some stuff about it to this thread.

I don't like the one-way.

Pros: Allows more rotational torque when turning. 4x4 RC buggies are prone to understeer because of the nature of their bound drivetrain. A one-way decouples the axles so they are less prone to understeer. And another way of looking at it, is that off-power the buggy is like 2wd while on-power it's 4wd. How this translates in terms of performance and handling is not something I've been able to zero in on yet. Perhaps, the one way is what's enabling the Db01 to slalom easier midspeed. I'm not sure yet. The buggy seems to be able to hook into turns better off power now. It just kind of sucks directly into and locks into corners because of the way the power train decouples and the fronts wheels are able to free spin when off power. And that can be a useful characteristic in a race.

Cons:
1) You have to cut out bits of the spur cover. I don't think this had ever been mentioned and I was completely surprised by this aspect. You have to trim the cover in order to avoid the one-way pulley abrading against the spur cover when it's been properly built and installed into the center shaft. I did not do the best job - and in fact my spur cover has a small hole from overcutting or overtrimming. No big deal but this is just one of those things that reveals how rather ad-hoc the center one-way is in the DB01.

2) Most of the times, for most conditions, the pro above is a subtle pro. You're not going to notice a mind blowing difference in turning between the one-way vs without.

3) The biggest disadvantage to using the center one-way, or any one-way, is that you lose braking on the front wheels. 4wheel braking gives far stabler braking in any condition and you get much greater stopping power. With the one-way, you'll spin out and do 180s when braking and that's desirable to me in..no way.. In fact it can be damaging to the power train. If you're going 40mph in one direction and then you brake, spinout and do a 180 and then you hit the throttle again in order to accelerate in the opposite direction, your drive train will be working against that momentum and you'll be more likely to strip out gears, which is I believe what's going on with my vehicle now.

4) The one-way isn't sturdy. There are rollpins that make up the one-way bearing that are prone to falling out if you're not careful.

All these reasons combined are, at least, enough for me to want to remove the one-way and return to stock. I don't like 2-wheel braking, guys. The move from 4 wheel to 2 wheel braking, in the end and overall, would make the one-way a definite hop-DOWN. And so after a month of tinkering around with it, I must say, I don't recommend it. I even think I ought to be paying someone a price in removing the one-way, as if that in itself were a hop-up!

Postedit:I've done some more testing. It turns out that spin outs when braking can be minimized with a softer suspension in the front. I rose the ride height of the front by moving the bottom mount toward the center, but then to add a little firmness to the shocks since it was drooping a little too much without any spacer, I added just a thin spacer on each shock, whereas normally I add a thicker spacer.With this tiny tweak my braking is straight and my DB01 doesn't spin out. So that's good. All it took was a change of the spacer or a slightly softer front suspension setup.

I also tweaked the rears so that they're noticeably negative in camber. Before they seemed closer to neutral if not neutral. My car seems to handle just fine under this new setting (negative rear camber + softer front suspension). I can still filp over but I have to force it now. I guess I just need to keep tuning this. The one-way is a good idea but it calls for heavy suspension and driving adjustment to be truly useful. I guess.

Colzy2

Hi Hwa224

Yes I agree with your comments about cutting part of the spur gear cover to fit a hop up & thought it was strange that for my double slipper clutch I had to cut a little part of the spur gear cover also.  Any hop up that requires modifying the main part of the car is frustrating, as if you take it off, then you have to generally replace the part you've had to modify to begin with.  I guess the manufacturers think the hopups won't be take out?

From most of what I've read on various forums, seems to be the single slipper clutch is the most popular - cost seems to be the biggest motivator for buying the single over the double.  Only reason I bought the double was I had been waiting for weeks for eTamiya to get my order finalised as they had run out of single clutch sets, so wanted to get my gear as soon as possible so ordered the double.

It's installed but as I'm only running a Tamiya Sport Tuned brushed motor, there's not a lot of benefit that the double slipper clutch gives me at the moment.  I'm not sure how the single compares to the double, but for now I wanted to "future proof" my car as I intend to get a brushless system at some stage.   What's frustrated me the most is the lack of larger tooth pinions available for a brushed system.  The smaller stock pinions are ok, but I went searching for larger pinions to get more speed out of the brushed motor.  I found some 22 & 23t 48 pitch gears, but found they were matched to the DB01 48p spur gear.   Arrggghhh.  Very frustrating as the larger pinion that came with the kit won't mesh correctly onto the spur (with the brushed motor having a bearing on the outside of the case this reduces the space available for the pinion to fit & therefore won't align correctly to the spur).

Is there a general consensus about a good, middle of the road brushless system & lipo battery that suits the DB01?  I'd love to hear from the group so I can plan for my next major purchase to really get some good speed out of the car.

Hwa224

Hi Colzy2,

Perhaps the Sport Tuned motor's shaft is too short? I don't believe you'll have a problem with most brushless motors, although even with them you'll have some issue aligning the spur with the pinion if the standard length is like mine. If I'm honest, I have an EZrun 8.5t and about 15-20% of the width of the pinion is not on the spur because the shaft is too short. But I don't see that as a real problem. There's enough area for the pinion and spurs to mesh there, IMO. Though I might be wrong.

If you go brushless, also consider buying a lipo battery and charger, if you haven't already. Brushless will make a vast difference and can be used with NIMH, but you'll find the Nimh running hot, and in fact you'll run the risk of running the battery too hot. Not to mention the inferior run times you'll be getting.

I'd suggest getting an EZRun 60a ESC or better. You can get them for about 50 US dollars. For the motor, try the 6.5t LRP Vector K4 motor. The LRP is a Team Associated brand, I think and the K4 line of their motors is their economy grade, but are still very good. They are completely rebuildable, come presoldered (EZRun doesn't and soldering turns out to be a major PITA), and are sensored. You can run the motor with sensored or sensorless ESCs, and it seems to have high temp tolerances. They sell for about 60-70 USD, although sometimes they are on sale for 55.

I don't have the LRP but I recommend it because it's something I'd buy if I had to do it over again. The EZrun 8.5t is plenty fast, but I yearn for something faster, although that probably doesn't make me wiser.

Today on a lunch break at work, I made use of a very large parking lot on the side of which was a strip of off road, nice little rocks and nice little hill of dirt, which I made use of for the first time.I did a lot of speed runs (on the parking lot) and then on that off road strip I did a lot of jumping. The DB01 handled itself superb, gliding through rough, rocky terrain and powering through and jumping off the dirt hills, and crash landing several times with no damage.

I have my DB01 geared at 23/90 and my motor temp after 30 minutes was 130-140F, which was only (barely) hot to the touch but not burning, but that's also with a Yeah Racing tornado fan on the motor. But that was also with the spur meshed too loose to the pinion, which is not good. Right now I'm shopping for replacement spurs. DB01 spur gears are compatible with Team Associated B4, B44.1, TC, SC10 spur gears, and a lot of aftermarket companies make spur gears for them - Kimbrough, JConcepts, Hot Racing, and such. Lots of options.

ElectricGuy007

[youtube]http://www.youtube.com/watch?v=V-BH8EFbQSk[/youtube]


Here's me trying speed runs with my 501x. I love the sound it makes when it Zooms by the camera.....
I estimate it goes close to 50MPH. If I had a saddle pack Lipo I bet it would hit close to 60Mph...

Hwa224

Electric_Guy,

I don't think it's just me but the video has a lot of artifacts, like 50% of the screen is covered in pixels. I can't see the car. And even without the pixels, the view is wanting, to say the least. You get no sense of scale or distance travelled, and therefore no sense of speed. But I do like the sound. Sounds kind of like Star Wars, no?

What tires are you riding on?

Hwa224

I took my DB01 for a spin during lunch again... It was making a rough noise. But I didn't think much about it. And then... suddenly no reverse. And then, suddenly it's FWD only.

I spun the rear wheels, there was no diff action whatsoever. The rear differential finally bit the dust. Or so I thought.

About 10 hours later when I have time to check it out, it's not the rear diff. It's the center pulley!

Freak. I knew I was running the rear belt a little too loose. I believe that's why it stripped out. The rear diff is still good. I mean, it's dirty as hell and doesn't feel smooth. So I'll need to rebuild and relube. But, since I have the gear diff coming in, I'm not even going to bother. My DB01 will be "on the lifts" or "in the garage" until I get the gear diff in. I'm going to storage charge my lipo. I was waiting for tje gear diff in the first place to readjust my belt. Oh well.

But that solves another mystery. When I rolled the DB01 by hand, I noticed a lot of tension. I thought it was spur/pinion mesh, which is why I tended to mesh the spur on the loose side. It didn't occur to me till very recently that the tension was a "rubber band" effect I was getting from the rear belt. I believe this is also the reason why my DB01 made the peculiar noise that it did when going full throttle. It sounded mildly "nitro". It was a belt that was too loose going full blast.

Good thing I have the one-way because that means I have an extra center pulley laying around. And good thing I had already purchased an extra belt. And good thing I have the gear diff coming around. I took off the diff covers for the rear for the first time ever. And it's not going to close till I get the gear diff installed.

Lesson learned.

ElectricGuy007

Im running proline tires, The Mini E-revo Road Rage tires on the rear, and Dirt Hawgs on the front. Basically a set of street tires.

Hwa224

I've had the DB01 since middle February. Since that time, I've played with tires and wheels, one-ways, fans, and shells. And I now have a gear diff in the rear, which I recommend more than any other hopup so far. The gear diff is smoother than a ball diff will ever be. The power delivery it gives is composed, predictable, consistent, direct, linear and any other adjective from this ballpark you can think of. It makes driving the car very simple. The car doesn't spin out and the forward traction is greater. I haven't had it for more than a week, so I can't comment on durability. But so far so good. I had the 10k diff oil but ultimately decided to use the 1k oil that comes with the gear diff kit. I also used green slime on the gasket and o rings to ward off leaks. But that's something I will be looking out for.I still have the ball diff in front. It's feeling a bit gritty and it's stiffer in diff action than the rear. But I won't be outright replacing it till I think I need to.

The downside of the DB01 gear diffs is 1) the possibility for leaks, 2) gears are plastic - they're supposed to be durable but how much so? against how much power? remains to be seen; 3) More mass. The gears have more plastic mass and are filled with diff oil. The rotating mass is greater and you can tell. There's less of a punch off throttle. And you can feel that mass when you hold the DB01 in your hand and punch the throttle the car lifts up or inclines as if it wants to wheelie, and there's a gyoscope effect that didn't exist with the ball diffs.

Anyway, I defintely recommend the gear diff. Again, I can't comment yet on how durable these are. But they're supposed to be more durable and involve far less maintenance than the ball diffs. The best part about the gear diff, besides that they are mechanically simple and direct, is that they correct so many of the traction and handling issues I've had. I don't have to wrestle with the DB01 in tight turns, no more crazy spin outs; and because the power delivery is so much more consistent, I get a lot more power off road, despite the thin oil that I'm using. One would think the opposite would be true due to the limited slip effect of the ball diffs, but it's clear to me that this is not so.

The gear diff, the alloy blocks and mount, slipper clutch, hotter motor, fans for the motor, replacement screws (since the stock screws rust), and a TBR bumper = best hopups for the DB01.

Hwa224

My DB01 after three months of playing with it: