2010.01.21, 06:07 PM
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#31
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Registered User
Join Date: May 2006
Location: Los Angeles
Posts: 375
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There are two force at work here. One is the wheelie force or holding the pinion force like you talked about. For the wheelie force, every rear wheel drive car has it. Does not matter what kind of drive train you have. The force goes from the tire to the diff gear to the motor. Since right side motor or left side motor have the same wheelie force, there was no point testing it.
The other is inertia force from the inertia of the motor rotor. The inertial force has to do with the weight of the accelerating motor rotor. That was what differentiate this mount from others. The motor on this mount is turning the “right” way. That was what I was trying to test. If you put a flywheel on the motor, you will have more of the effect.
I was expecting more force transfer because on Slash trucks, the car tilts when you accelerate due to motor rotor inertia.
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2010.01.21, 06:17 PM
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#32
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Registered User
Join Date: Aug 2002
Location: Burnaby, B.C.
Posts: 222
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Ben: For the wheelie force, it doesn't even have to be rear wheel drive. Front or all wheel drive will see the same effect of weight transfer. I think we're on the same page about the forces though. The magnitude of the force will be larger when the car is actually trying to accelerate vs when the pinion is free to spin. So it may be premature to dismiss the advantages because the gains are too small from the free spinning pinion test. With a flywheel you definitely see more of an effect but what size flywheel will correspond to the actual load when accelerate will be hard to determine.
yasuji: I've had the car running with the center shock and without. I haven't tested them back to back but I think i preferred the setup with the center shock. The pod angle won't change the fact that this pod will increase the weight transfer to the rear wheels. It works completely independent of the angle.
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2010.01.21, 07:22 PM
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#33
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Moderator
Join Date: Dec 2004
Location: Los Angeles (Pasadena), CA, USA
Posts: 2,809
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Quote:
Originally Posted by benmlee
Just for curiosity, may be I will run a simulation at work next week after work. We have a dynamic simulation program that Ford and some race teams use to run simulation on suspensions among many other uses for other industries. It will tell you the whole story (If you set it up right).
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This, along with TJ's test results, should be very good info to look forward to. Please do, Ben.
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2010.01.22, 03:43 AM
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#34
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Registered User
Join Date: Sep 2007
Posts: 1,840
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Once received, the pod will be tested and compared to another laydown pod in 98mm config using one body, 07 NSX with PN 33 turn modified motor on my MR03 and It will be tested on low, mid and high traction RCP tracks. Ofcourse lap times will be posted as well.
Thanks!
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2010.01.22, 08:40 AM
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#35
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02-Racer
Join Date: Sep 2004
Location: Belgium - Holsbeek
Posts: 949
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Tjay,
I already ran on different RCP tracks from different clubs here in Belgium and they are always kind of different in traction. Because you mention low, mid and high traction RCP tracks, do you know what has an influence and how do you pick these?
Hope you understand my question
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2010.01.22, 09:50 AM
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#36
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Registered User
Join Date: Sep 2007
Posts: 1,840
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Quote:
Originally Posted by HaCo
Tjay,
I already ran on different RCP tracks from different clubs here in Belgium and they are always kind of different in traction. Because you mention low, mid and high traction RCP tracks, do you know what has an influence and how do you pick these?
Hope you understand my question
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HaCo,
I go to 2 tracks locally. One has mid to high traction (depending on temp) and one that has lower than usual. The mid-high traction is just your normal RCP track to where almost all soft rear tires from all manuf will work. The low traction on the other hand is very unique. Only those that knows "throttle control" survives the race. On this track, it is very hard to put the power to the ground on a 2WD even if you have the best set of tires and horsepower doesn't matter as much. Honestly speaking, this track almost has a "carpet" feel to it. When I use to play my AWD MOD fulltime, the car just loves this track. I didn't have to worry much about traction roll or having to super glue the sidewalls and i was able to use brand new kyo20 rear/kyo30 front with just double sided tape. Ask any AWD mod drivers, you must run glued tires and/or trued/worn down tires on a regular RCP track. Also, tires lasts 5x longer than it's normal runtime, believe it! If anyone mentions they want the car to roll or to drive their miniz with bigger scale RC feel, this is the track and all of you guys are welcome to try it this coming KO Grand Prix in April 24, you'll know what I mean but you may end up extending your vacation...
*
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2010.01.22, 12:47 PM
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#37
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tire schredder
Join Date: Sep 2008
Posts: 864
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open case ceramic bearings will eliminate your drivetrain losses and delrin idler gears will also help.
__________________
MantisWorx
www.rcshox.com
professional RC products
Marcus Williams
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2010.01.22, 01:21 PM
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#38
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Registered User
Join Date: Sep 2007
Posts: 1,840
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Quote:
Originally Posted by Tjay
HaCo,
I go to 2 tracks locally. One has mid to high traction (depending on temp) and one that has lower than usual. The mid-high traction is just your normal RCP track to where almost all soft rear tires from all manuf will work. The low traction on the other hand is very unique. Only those that knows "throttle control" survives the race. On this track, it is very hard to put the power to the ground on a 2WD even if you have the best set of tires and horsepower doesn't matter as much. Honestly speaking, this track almost has a "carpet" feel to it. When I use to play my AWD MOD fulltime, the car just loves this track. I didn't have to worry much about traction roll or having to super glue the sidewalls and i was able to use brand new kyo20 rear/kyo30 front with just double sided tape. Ask any AWD mod drivers, you must run glued tires and/or trued/worn down tires on a regular RCP track. Also, tires lasts 5x longer than it's normal runtime, believe it! If anyone mentions they want the car to roll or to drive their miniz with bigger scale RC feel, this is the track and all of you guys are welcome to try it this coming KO Grand Prix in April 24, you'll know what I mean but you may end up extending your vacation...
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... Mid-High traction test: As mentioned above, this is your typical RCP track. I want to test on this track to see if the added rear traction is beneficial to the current tires being use (PN6= tons of grip but so little runtime in them) or will it make the rear end to "hop" (wheel hop), or will it make the kyosho 20 slicks feel like a PN6? (kyosho 20 rear slicks has the longest runtime of all stickiest tires available for miniz). Maybe it'll be the time for us to use that hard top shock springs, who knows?
As for Low Traction test: Obviously, I WANT REAR TRACTION!!! lol I'm really hoping that this "sidewinder" pod will give this extra rear grip that everyone needs on a low grip track. I am mainly concern on how this pod will do on a low track... I'm itching to try it, NOW! lol...
As for what Ronac had said regarding the drivetrain loss, well he is right. I myself will probably not going to be able to tell the difference between with idler gear and without idler gear. Especially not in mod class and add if you add what Marcus had just mentioned, this should eliminate the "loss" that you may feel.
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2010.01.22, 01:33 PM
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#39
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PN RacingTEAM Driver
Join Date: Jul 2007
Location: southern calfornia
Posts: 1,530
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looking forward to hear the results....
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2010.01.22, 01:44 PM
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#40
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Registered User
Join Date: Aug 2002
Location: Burnaby, B.C.
Posts: 222
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Tjay: I can't wait for results either! For the different grip levels of RCP, what side of the track are they?
MantisMMA: Ceramic bearings would be a great upgrade since its at faster RPM's then the wheels so the difference from regular to ceramic will be more noticeable. When I made my prototype, I would ideally have used delrin. The problem was I couldn't find an off the shelf pinion in 64 pitch. So in the end, I resorted to modifying an aluminum pinion design for larger scale cars.
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2010.01.22, 01:47 PM
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#41
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Registered User
Join Date: Sep 2007
Posts: 1,840
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Quote:
Originally Posted by Ronac
Tjay: I can't wait for results either! For the different grip levels of RCP, what side of the track are they?
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I haven't tried the back side Ron so I would refer to it as, "the correct" side.
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2010.01.22, 01:50 PM
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#42
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Registered User
Join Date: Aug 2002
Location: Burnaby, B.C.
Posts: 222
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I guess the back side you're referring to is the smooth side? It's weird cause the racers here in Vancouver have gotten accustomed to the smooth side.
Honestly, I prefer the rough side but like everyone else here, I've just gotten used to the smooth side.
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2010.01.22, 02:08 PM
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#43
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Registered User
Join Date: Sep 2007
Posts: 1,840
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I haven't tried the "smooth/back side". It's probably better and more consistent than the rough side but most of the manufacturer designed their products with the RCP rough side in mind. Also, big events uses this side. This is probably why we use them as well. It's good to have drivers like yourself to run on different type of surface. This way guys like us may benefit from it just incase we do come and play with you guys and vice-versa.
Just a thought. Since you want more rear traction on that smooth RCP surface, why not have the motor sit up higher just like the ATM 96mm pod or PN's 94-98mm pod? This way you'll get more corner speed instead of having a motor that sits flat and low. Just a thought...
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2010.01.22, 02:17 PM
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#44
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Registered User
Join Date: Aug 2002
Location: Burnaby, B.C.
Posts: 222
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I actually think that the smooth side gets dirty more easily then the rough side so its actually less consistent. Unless you ALWAYS keep it dirty, which it seems like something we do here.
I'll be doing exactly what you recommended since my proto pod is in the mail. I'll be setting my MR-03 up with a SC430 body and 94 mid mount pod. I'm not quite sure how having the higher motor will translate to faster cornering speeds though. Physics is physics so I typically try to keep the cg as low as possible.
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2010.01.24, 10:27 AM
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#45
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Registered User
Join Date: Aug 2008
Location: São paulo, Brazil
Posts: 282
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Hi guys...
I was reading this thread, and for me, it will work. One thing that I didn't read here is about "momentum". The test made by Ronac on the track was described as "a different way to drive", where you may live the trottle and in the meadle of the curve you may accelerate the car with less spinning probability.
For me, what makes sence is that at the exact moment that you accelerate during the curve, you'll get all the beneffits of both parts (mottor and wheels) rotating to the same direction. The moment you pull the trigger is when you need all the forces pushing your tires against the track, and when you have a regular motorpod, occurs the opposite. That milisecond with less traction is exactly the milisecond that your motor is passing from 10.000RPM to 15.000RPM (remembering that the torque is instantaneous on eletric motors).
I think is all about that milisecond, inversing the forces that may reduce the spin out probability over 50%, depending on the track.
My opinion. Good work Ronac! Following this topic!
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