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"Experienced user"
Billy Kelly - 8.11.17, 6:06 pm Post #331: | Reply With Quote
They should work fine. Brushless makes nice change in these.
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RGunn - 8.12.17, 4:32 pm Post #332: | Reply With Quote
This is why I don't advocate using grease or lube on nylon gears in a non-sealed diff. or gears.

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RGunn - 8.12.17, 4:33 pm Post #333: | Reply With Quote
This goes with the reply above. For some reason the board will only let me post one photo per reply???

"Experienced user"
re-run - 8.13.17, 6:24 pm Post #334: | Reply With Quote
Well rgunn, I have been doing rc for quite number of years. Aside from power source changes and brushless, little has truly changed. All the tips mentioned, aside from the questionable tabs, have been used for 30 years+.

Dirt in the diffs is going to happen no matter what but think on this, there are probably very few semi/pro racers that would run without some sort of lube in the diff. Lube or not, you cannot get away from cleanings, and lube is going to make it last longer. After all, by your logic, bearings should not get oil, and I bet almost everyone oils their bearings. If you need another example, not so rc related but still applicable. A properly cleaned/lubed motorcycle chain is always going to last longer than a dry chain.
So, while it is your choice to lube your diff or not, you are not likely to make it last longer, or even as long. These diffs are cheap though, so do what you wish. Lubing though, does not mean cramming the whole thing full of lube. Just a light greasing.

I stand by what I said on the tabs, Sorry, but at best, with a stock set up, cutting the tabs will likely gain seconds of runtime, if any. I have one in my hand as I type this. And upon looking at it more, I would actually advise against cutting the tabs.

I can spin the bearing and there is less drag than a pencil lightly across paper. There IS 1 job the tabs DO have that no one seems to have thought of, alignment. Take a bearing off, now grab the outdrive cup with your fingers, now wiggle. They wiggle and guess what, you don't want that. Doing that will grossly wear out the insides of the diff, the cups, and the dogbones much faster. Those little tabs prevent a good amount of that wiggle. Obviously there is no way to totally stop it, because then there would be too much drag.

So cutting the tabs is not really a fix for anything as the additional wear will create much more friction in the long run. A true fix would be a redesign of the housing and diff, but that makes the car more expensive.

So, in the end, you can cut the tabs if you want, but I am of the firm opinion that doing so will ultimately not gain you a single thing.

Still, your car so your choice. And others can make their choice however they see fit.
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RGunn - 8.13.17, 8:51 pm Post #335: | Reply With Quote
Re-run, Did I piss you off or something? Why the attitude???

I will however have to respectfully disagree with about everything you said above. If those tabs are such a great idea why is it that no other similar diff. housing/cup design uses those tabs?

Grit/dirt mixed with even the smallest amount of lube will cause more wear to nylon gears than nylon gears that are run dry.

With respect to your motorcycle chain analogy, I raced MX for almost 15-years during the 70s & 80s and also wrenched for an AMA Hall of Fame member (Preston Petty). I know a a bit about motorcycle chains.

I have been my Grandson's mechanic and coach for the last three years so I am still involved with Motocross today. The majority of MX riders today do not use so-called, 'chain lube'. The reason is that 'chain lube' is so sticky/tacky that dirt and debris stick to the chain causing premature chain, and especially sprocket wear (relate this to our rc gears). Most MX racers use WD40. Not because WD is a great lubricant, because it's not. We use it because it doesn't attracts and hold dirt. So long as it's applied between every moto or practice session it lubes fine and chain clean-up is easy when cleaning-up the bike.

As you suggested, "each to their own" with regard to this issue about the diff. tabs & lubing nylon gears in non-sealed diffs. With no more to go on that what seems logical, I'll go with dry nylon.
"Experienced user"
re-run - 8.14.17, 1:37 pm Post #336: | Reply With Quote
Well disagree if you want but just because you havent seen it before, does not mean anything. Look yourself. Take the diff out and wiggle the drive cup. Not the play. Now pull that bearing and wiggle again. Significantly more, isnt there. Now IF you have all that mechanical exp, you'd know that extra slop is not going to help anything. Taking those tabs off will introduce that extra slop. How about this. I'll contact the manufacturer. Who knows maybe i will get am answer to this. In the meantime, the tabs stay on mine until someone can run a tabbed and tabless diff in controlled conditions and come up with a definitive result.

In a run once situation, wd40 isnt a big deal, but it hardly speaks anything to longevity. I doubt you clean your diffs after every run, so lets keep to the topic here, which is longevity. Simple roller chain can easily go 20,000 miles with average clean/lubes. If a bike has an auto oiler, even longer. And for the rare bike with oil bath chains, a long long time beyond that. But again, tell me the semi/pro rcer that doesnt use some sort of diff lube, even on dirt. Halsey, kinwald, losi, all use lube. Still, the majority of non-racers will use an o-ring chain and a dry lube. So, a dry lube and a lube in the chain.

Not trying to be rude, but sometimes some advice may not be the best. Kinda like people that do not run fork braces on sohc cb750s.
Oh it can be done, but isnt a good idea.
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RGunn - 8.14.17, 4:48 pm Post #337: | Reply With Quote
Re-run, look, we are arguing over an issue with a tiny toy car that is part of a hobby we both enjoy. Seems kinda silly doesn't it?

I get your point about the bearing tabs on the diff. case & ring-gear adding needed stability for the outdrives. However, it's not needed as that same stability comes from the gear box holding the bearing in a concentric and stable position. Any slop that exist with the outdrives is because of the difference in O.D. of the outdrives and the I.D. of the bearing's inner race. Since the bearing is held by the gearbox, the tabs do more harm than good because of their grip on the bearing, thus drag on the diff. housing.

No offense meant, and I appreciate the conversation, but we'll have to 'agree to disagree' about this as it seems we both see the issue differently. As you mentioned, it's all conjecture anyway as there is no testing to prove one way or the other. And frankly, I don't care what Dromida has to say. Do you really think they would 'own' a defect in their product???

Bye the way, just finished install and ran one of our trucks with the new brushless setup and modded diffs! All I can say Is WOW! What a huge difference over the brushed motor!

If the diffs. strip in short order I'll report here and consider "eating crow" on the tabs issue.
"Experienced user"
Billy Kelly - 8.14.17, 5:35 pm Post #338: | Reply With Quote
Good to read that brushless look good for ya. Thumb up on the arguing over toy cars thing. Happens way too much. Not here, well not anymore. Things got really ugly a couple years ago.
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"New user"
RGunn - 8.14.17, 6:43 pm Post #339: | Reply With Quote
Billy, I'm blown away at how fast and smooth the truck is with the brushless setup, and with stock NIMH batts. at that! With the throttle dual rate set at about 70% the truck is about the same speed as it was wide open with the stock brushed motor. Same gearing. etc And of course, the programmable options for the ESC add even more functionality.

Of course, I have no gauge as to improvement or not from the diff. mod. and grease removed. I can only say that the drive drain feels more free when I flip the truck on it's top and turn the drive train by hand.

The other noticeable change was the brushless motor was not getting near as hot as did the brushed version. I worked the heat sinks down in diameter to fit on the smaller O.D. brushless motor and they dissipate heat well.

So far looking good (crosses fingers)!
"Experienced user"
Billy Kelly - 8.14.17, 7:02 pm Post #340: | Reply With Quote
Yeah, sounds strange to me still, but brushless with nimh works for these. I used to be lips only with them. Mostly cause the original stock battery was unreliable. I've kept the brushless touring car on nimh for almost a year. I did try 2s but was too much for the 1/18 layout.
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