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Old 08-04-2014, 12:12 PM
  #21766  
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Originally Posted by jiml
Can you explain the theory behind running a gear diff with putty over a ball diff? I'm curious about that.

And who painted the body? Nice!
Dean Issac paints the bodies not. The picture does not do it justice, the detailed skulls in the gray silver area are fantastic.

The only ball diff to use in an M03 if from the mantra ray and its doesn't get tight enough. The diff putty is better suited for the M03. IMO, the additional weight of the diff gear adds more weight the car at the best location. just over the wheels and acts as a fly wheel to keep the car rolling through the corners. With the brushless motors, torque is not a problem so don't let the additional weight concern you at a dead start. I still have to turn the throttle expo down to -20% to keep the wheel from spinning at a dead stop on asphalt.

Important: when you store your Mini using a gear diff, be sure to store it on its side with the screw side of the diff facing up. This will keep the diff fluid in the diff and prevent from leaking out if the car was on all four wheels. Not so important if you use the diff putty but more important if you use a silicone diff fluid, regardless of the weight. Hope these tips helps
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Old 08-04-2014, 12:19 PM
  #21767  
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Originally Posted by sosidge
I sincerely doubt that a ball diff would be quicker than a gear diff but if you want to run a ball diff the Tamiya TA03 diff is the one do get. I would steer well clear of the 3Racing ball diff.

Gear diffs are advantageous because there is no slip and all the power can be put down on the ground. The difficulty with the Tamiya kit diff is getting a consistent build, but I have seen putty diffs go very quickly indeed.
For the M05 Mini, (both v1 and v2) I use the Tamiya ball diff with the alum outdrives. I think its for the TA05? You have to use plastic outdrive cushions on the universal pins to fit properly. Actually, gear diffs have a higher chance of "diffin out" as you go through a corner, less likely with the ball diff. Try using Losi brown diff grease on your ball diff and over tighten the ball diff by adding an extra shim between the diff sling and the case. This will allow you to tighten the diff much greater. Also the brown Losi diff grease is sticky and limits diff action.
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Old 08-04-2014, 12:29 PM
  #21768  
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Originally Posted by eR1c
Quick question,
I realize this has probably been answered, I have read through countless posts and searched all over the web. But still, this question isn't totally answered for me. Figured some of you may know?

I have been racing my M05 in the Mini class, -we follow the TCS rules. Motors have to be stock silvercan, no funny business in terms of adjusting the timing, etc.

I am consistently getting about 3-5 place out of about 15 competitors. Which is good, but just can't seem to get into the 1st or 2nd spot. I have done endless tweaks to my car, -in the corners I am just as fast as the tops spots, yet I am dying on the long straights. In fact I would say that more than 1/2 of the field beats me on the straights (I make up the diff' in the corners and overall I think I drive a tighter line than most guys and thus run faster lap times). But the straights my car is dog slow. It is noticeably slower on the straights. I do not believe this has anything do w/ skill/driving ability -as mentioned I pull out ahead in the twists ...which I attribute to superior driving skills

I have raced for years, but am fairly new to the MINI class, -this is my first season and we are nearing the end.

Are some silvercan motors dud's? -i mean are they slower than others? It appears to me that there is about 30% in the field who have fast motors, 60% who have average motors and about 10% myself included who's motors seem slower. -ie, on the straights I am just getting passed. I have no power on the straights.

I am running a 45c Trakpower lipo,
Traxxas ESC (pulled from a slash, -brand new when I began using it)
Motor is the stock silvercan that came w/ my Mini kit.
I do have another silvercan from another application from years ago, the wires and housing are the same, yet the end cap is a different color (than the one that came in my kit). I have read that there are many different "silvercan" motors out there. Some say certain ones are more desirable. I don't want to cheat, so not really sure if I should be looking for some coveted silvercan ...unless that is what everyone is doing? Yet also which silvercan is the best is a bit murky to me.

I suspect that my speed has to do either w/ the battery, esc or motor. I suspect motor? Am I wrong.

Is most of the field cheating and doing something to their motors that I am unaware of? Is there some trick? ...I actually think that the Mini class in some ways is the most uneven, I run 17.5 on road and that really comes down to driver skill as all cars seem pretty equal (but I digress).
Tamiya in the US has moved away from Silver Can Mini racing for TCS and replaced it 21.5 brushless. The goal, to eliminate the voodoo with silver can motors and variance differences. However, I was not a fan of this because I always felt and still feel there is more voodoo potential with brushless.

If you're racing with silver can motors, you MUST have a much more motor checker to measure the RPM. TCS Silvercan limit was 17,750. The issue is there are silver can motors available that spin over 29,000. So unless the entire field is subject to a motor test, you never know what you're competing against. The other issue is silver cans get faster over time. I had a situation, a few years atom when my motor was 80rpm over the 17.750 limit at the end of race. I always tuned my motors to 17,500 with a 250 cushion. In this case my motor exceeded the limit and was DQ'd. Sucked for me as everyone (not really just one person) was pointing fingers. Now I don't have to worry about that as brushless takes away the RPM limit, but you have other areas to worry about. (i.e.: motor temp) Funny that I'm racing electric and tuning my motor with a nitro temp gun
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Old 08-04-2014, 12:42 PM
  #21769  
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Carl,

Thanks for the info,
Our club is using the older TCS rules, -I did see however that Tamiya changed the rules ...our club has been slow to adopt i guess.

I couldn't agree more w/ your assessment of the brushless vs voodoo in silvercans. You do not see this issue at all w/ the brushless setups. I run on-road expert class, the cars are all the same speed even w/ a ton of different brands being run. Any minute difference is not noticed and really can be made up w/ driving skills and car chassis setup in my opinion. At the speeds of on-road class, a good driver is more than half the battle. -Good driver will beat out speed anyday in most brushless classes ..as there is plenty of speed on tap.

The Mini class is so much slower that you are really trying to squeeze as much power as you can out of the car ...so every drop counts! ..on the straights I feel like I am yelling "row-row-row"!
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Old 08-04-2014, 01:03 PM
  #21770  
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The age old decision ball diff or gear diff.
I've been tooling around with minis for a good while. It always seemed like a you had to compromise, ball diff - good off power turn in but blah blah out of the corners. Gear diff - plows into the turn, bad off power steering, but jumps off the corner with tons of on power steering.
Both required constant maintenance. Ball diff backs out and loosens or the gear diff moves the putty around seeping out through the bearings and axles.
Often people try to lock the Ta03 ball diff and this would eventually strip the axle splines. I've put off the gear diff putty rebuild and had putty in the bearings causing slow speeds and hot motors.
Recently, I played around with mini again and settled on something slightly different. People may have been doing this already but I am willing to post it.
I switched minis back to an M05.
I used the M05 aluminum Ball diff.
Build it as per instructions with only these few changes:
Sand the diff rings with 600 grit sandpaper, don't want polished smooth rings here.
used the supplied steel balls minus one ball. use a body reamer remove the slight round edge built into the spur gear for the diff balls for this one hole.
use one of the Tamiya Bushings (Tamiya 54424). Slightly sand both surfaces that will touch the diff rings.
follow the rest of the diff building instructions.
Now you can tighten or loosen the diff as you please. no more messy putty or braking diffs trying to tighten them beyond breaking.
You will find that you don't have to tighten the diff so much break the bolt. you can loosen the diff screw to find a nice balance of off power steering. If people are jumping off of the corner you can tighten the diff to get the right amount of on power steering.
the settings stay put so less maintenance. It worked out real nice for me. I cannot guarantee the results for you and do this at your own risk and supply.
Good luck.
P.S. this can also be done with the TA03 Ball diff used in the M03 minis.

Er1c - Like I said... Mini is a goldfish bowl full of sharks.
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Old 08-04-2014, 01:08 PM
  #21771  
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Originally Posted by Carl Giordano
Tamiya in the US has moved away from Silver Can Mini racing for TCS and replaced it 21.5 brushless. The goal, to eliminate the voodoo with silver can motors and variance differences. However, I was not a fan of this because I always felt and still feel there is more voodoo potential with brushless.

If you're racing with silver can motors, you MUST have a much more motor checker to measure the RPM. TCS Silvercan limit was 17,750. The issue is there are silver can motors available that spin over 29,000. So unless the entire field is subject to a motor test, you never know what you're competing against. The other issue is silver cans get faster over time. I had a situation, a few years atom when my motor was 80rpm over the 17.750 limit at the end of race. I always tuned my motors to 17,500 with a 250 cushion. In this case my motor exceeded the limit and was DQ'd. Sucked for me as everyone (not really just one person) was pointing fingers. Now I don't have to worry about that as brushless takes away the RPM limit, but you have other areas to worry about. (i.e.: motor temp) Funny that I'm racing electric and tuning my motor with a nitro temp gun
I think you are 100% dead on as to your Silvercan and B/L motor comments. After TCS rules went to rpm limiting the Silvercans, much of the Voodoo was eliminated. The last rpm limit was 18,750 @ 7.2v not 17,750 tho. I know, it's easy to forget stuff like this, as I know you knew the right RPMs.

What was interesting about the rpm limits was the testing post race was what made it difficult. As many of you may be aware, a hot Silvercan will test as much as 3 or 400 more rpm than a cool one. A motor that did not pass the rpm limit after 5 min could easily pass after 10 or more minutes.

A lot of the guys here were setting the motors to come of above the rpm limit, depending on the motor to cool off enough to make the rpm limit. This at times was a little problematic if they tested the motors sooner than anticipated.

Since we're talking about motor temps, so far, what I've been hearing is that the motors in a v2 run higher than a regular 05 and much higher than the M03. Makes me wonder if there might be a trade off in the possible advantage of a square pack and the inability to advance the timing as much due to motor heat.
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Old 08-04-2014, 01:12 PM
  #21772  
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Has anyone posted an upgrade for the droop screws on the Ver2 M05? I don't see how the chassis won't be destroyed after one race day. I'll probably just adjust droop the old way with shock length, unless someone has a good idea for protecting the chassis.
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Old 08-04-2014, 01:12 PM
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oops

Last edited by Timbulb; 08-04-2014 at 01:15 PM. Reason: oops
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Old 08-04-2014, 01:13 PM
  #21774  
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Originally Posted by Markus
The age old decision ball diff or gear diff.
I've been tooling around with minis for a good while. It always seemed like a you had to compromise, ball diff - good off power turn in but blah blah out of the corners. Gear diff - plows into the turn, bad off power steering, but jumps off the corner with tons of on power steering.
Both required constant maintenance. Ball diff backs out and loosens or the gear diff moves the putty around seeping out through the bearings and axles.
Often people try to lock the Ta03 ball diff and this would eventually strip the axle splines. I've put off the gear diff putty rebuild and had putty in the bearings causing slow speeds and hot motors.
Recently, I played around with mini again and settled on something slightly different. People may have been doing this already but I am willing to post it.
I switched minis back to an M05.
I used the M05 aluminum Ball diff.
Build it as per instructions with only these few changes:
Sand the diff rings with 600 grit sandpaper, don't want polished smooth rings here.
used the supplied steel balls minus one ball. use a body reamer remove the slight round edge built into the spur gear for the diff balls.
use one of the Tamiya Bushings (Tamiya 54424). Slightly sand both surfaces that will touch the diff rings.
follow the rest of the diff building instructions.
Now you can tighten or loosen the diff as you please. no more messy putty or braking diffs trying to tighten them beyond breaking.
You will find that you don't have to tighten the diff so much break the bolt. you can loosen the diff screw to find a nice balance of off power steering. If people are jumping off of the corner you can tighten the diff to get the right amount of on power steering.
the settings stay put so less maintenance. It worked out real nice for me. I cannot guarantee the results for you and do this at your own risk and supply.
Good luck.
P.S. this can also be done with the TA03 Ball diff used in the M03 minis.

Er1c - Like I said... Mini is a goldfish bowl full of sharks.
curious why you only use one-peg? I would think this would create an offset in the diff plate pressure and the peg is not the same thickness as a diff ball. A good suggestion, but would have thought to have a balanced number of pegs in the diff?
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Old 08-04-2014, 01:18 PM
  #21775  
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geesh,
this variance in slivercans is driving me a bit nuts.

I absolutely do not want to cheat, but is also sucks racing against guys who obviously have faster motors. Well, it's all about fun ...I am enjoying it so that is all that matters.

I do have a few silvercans at home, I may do some comparrisons to see if some are faster than others?

Can ESC's make our silvercans faster?
Wondering if my Traxxas esc isn't delivering enough battery to the motor? or, phrased different, if other guys using a different ESC have an advantage w/ higher burst rates?? My Traxxas says it delivers a constant 100A of power, whereas a LRP or Novak may have a constant of 70A but a burst of 370A (my traxxas doesn't specify what the burst rates are -if any)?
Would this play a factor???
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Old 08-04-2014, 01:23 PM
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*important. I should have mentioned. use calipers and sand the bushing to be just a hair larger than the diff balls. I tired may configs:
All bushings had no diff action and caused weird handling problems both on and off power unless it was a tightened to a true spool (I wanted some diff action).
I tried 4 bushings across from each other and still locked it up too much, not enough diff action. I wanted slight diff action for two reasons: slightly better off power turn in and in a crash I wanted the diff to give so it didn't break diff parts.
I tired 2 bushings and same as 4 bushings; locked the diff up too much.
I settled on one bushing because it gave me the best control to almost lock it up with full diff action if I wanted it.
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Old 08-04-2014, 01:42 PM
  #21777  
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[QUOTE=eR1c;13444850]Quick question,
I realize this has probably been answered, I have read through countless posts and searched all over the web. But still, this question isn't totally answered for me. Figured some of you may know?

I have been racing my M05 in the Mini class, -we follow the TCS rules. Motors have to be stock silvercan, no funny business in terms of adjusting the timing, etc.

I posted much of this awhile back, but it looks as if you missed it. Yes, there are a lot of different Silvercans, but the TCS legal one is the #53689. If you're losing straightaway speed, 9 times out of 10, it's due to a dirty motor and comm. Yes there are duds, but very few of them these days. Maybe there was a little better quality control on these last run of motors.

Cleaning the motor-----warm water, dish detergent and a good shake and rinse works very well

Polishing the comm-----Use an old wire tipped oiling bottle and add a little metal polish like Brasso. My favorite is Mothers chrome polish.
deposit directly on the comm, spin over by hand. It's easier to do if you put the pinion on. Flush out with a stream of water.

This stuff take only a few minutes to do and is worthwhile. I'm sure you'll come up with your own variations to the procedure.

The slot car guys use a Comm drop, VooDoo drops that is very effective. Put one small drop on before each and every run and that will cut down on the number of times you polish the comm and give you a boost for a few laps. You'll find it on e-bay.

There's a lot more stuff you can do to enhance a motors performance, but winning just because you have the fastest motor doesn't prove anything.
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Old 08-04-2014, 01:48 PM
  #21778  
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Thanks for the advice Granpa,
-this is all valuable information.

I am having fun with this and it isn't all about winning, -agreed.
Yet in the Mini class there does seem to be a disparity in terms of speed. Which is important because speed is at a huge premium in this class. Other classes control and good driving may take 1st prize more than speed alone (I get that 100%).

thanks for the info,
I am going to try the suggestions you've given.
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Old 08-04-2014, 01:50 PM
  #21779  
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Originally Posted by eR1c
Quick question,
I am running a 45c Trakpower lipo,
Traxxas ESC (pulled from a slash, -brand new when I began using it)
Motor is the stock silvercan that came w/ my Mini kit.
I do have another silvercan from another application from years ago, the wires and housing are the same, yet the end cap is a different color (than the one that came in my kit). I have read that there are many different "silvercan" motors out there. Some say certain ones are more desirable. I don't want to cheat, so not really sure if I should be looking for some coveted silvercan ...unless that is what everyone is doing? Yet also which silvercan is the best is a bit murky to me.
Well, the kit Mabuchi silvercans aren't very good. The Johnson 540-J is the motor which was run in the TCS series... You may want to just start there.

Edit: I see Granpa just mentioned this [sort of ]
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Old 08-04-2014, 02:02 PM
  #21780  
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Well, the kit Mabuchi silvercans aren't very good. The Johnson 540-J is the motor which was run in the TCS series... You may want to just start there.
Thanks!
-that is helpful, I do have a Johnson 540 motor at home (bought years ago separate from any kit). -I am going to try it out and see if it is faster than the kit Mabuchi motor. My kit motor just seems really slow. ...i'd come out near last in an all mini drag race.
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