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Old 03-11-2015, 01:09 PM   #6466
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I don't understand FDR. How do you calculate it?
Also, do the size of the diff wheel (where the belt connects front and back) have anything to do with it? Or are those wheels standard across the board
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Old 03-11-2015, 01:49 PM   #6467
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I don't understand FDR. How do you calculate it?
Also, do the size of the diff wheel (where the belt connects front and back) have anything to do with it? Or are those wheels standard across the board
It's the ratio from the motor to the drive axles and is a function of the tooth count on the pinion, spur, central hub and gear pulleys. Unless you've changed the hub and gear pulleys, the internal drive ratio of the 417 is 1.947 (that is, 37 teeth on the diff divided by 19 on the hub). The manual has a picture that shows this, but it's quite easy: FDR= spur/pinion * 1.947 (for a standard set up).

The other term used to describe this is "rollout" that calculates the actual distance the car will move forward for one revolution of the motor. This is an absolute measure and can be compared across configurations and designs. However, because we use rubber tyres with a constant diameter (generally), this doesn't add much to the discussion for TC where I race.

There are some tools & apps around that generate charts of spur/pinion combinations to save your mind at the track. Any spreadsheet can do it easily, too.
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Old 03-11-2015, 01:52 PM   #6468
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The pinion, spur, centre pulleys and diff/drive (front and rear) pulleys all affect the "Final Drive Ratio"

You will have likely heard the term "internal ratio" bandied around. In the manual it will tell you this is 1.947 for the 417.

This is a function of the centre pulleys and the drive pulley.

So for the 417 the ratio is 37t / 19t = 1.947

Most 1:10th TCs are around the 1.8-2.1 mark. The 418 and 419 are now 1.85 for example. They use 37t drive with a 20t centre.

What you can effect (assuming you don't change these two from stock!) is the spur and pinion.

So say you have the stock 113t spur and you use a 30t pinion the calculation is:

113/30 * 1.947 = 7.34

Edit: too slow. Now you have two answers
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Old 03-11-2015, 02:21 PM   #6469
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thank you guys!
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Old 04-08-2015, 09:06 PM   #6470
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I have a TRF417 with the hard Raceberry chassis running 17.5 and I was wondering what shock oil and spring should I run for optimum driveability on indoor carpet? I have Tamiya type-C tires with soft inserts, TRF419 rear diff (Losi 2000 wt.) and a TRF417 diff (metal gears with Tamiya putty), & DCJ's up front. Should I be using 400 wt. in the front and 450 wt. in the rear and soft springs (RIDE purple)?

I went on PetitRC and based my set up off of Craig McPhee's Carpet setup @Yatabe Arena but I noticed that he is using a 4.5 motor. I'm just unsure of how much variation there is when it comes to motor turns vs. suspension setup.
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Old 04-08-2015, 10:02 PM   #6471
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Autostrada,

Try using all 40 wt oil front and rear with the Tamiya springs. Blue front and yellow rear, or all yellow. I'm not sure about the Tamiya carpet tires, but with that spring and oil combination using comparable Sorex 28 or 32 tires, your basic carpet setup should work. I still have a 417v5 that I run on carpet with these settings and can do very well with it. 17.5 powered cars can run softer than the higher power motors as weight transition isn't as abrupt. If you're racing in cooler climates, drop the oil down to 35 or 37.5 weights. My oil references are for Associated silicone oil. You will have to try and see what works for your driving style/ track layout.

Also, look at the other carpet setups. On petit, look at Sean Williams's setup as I run the same track he did his car setup on.

Last edited by greenpea76; 04-08-2015 at 10:12 PM.
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Old 04-09-2015, 02:19 AM   #6472
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Originally Posted by greenpea76 View Post
Autostrada,

Try using all 40 wt oil front and rear with the Tamiya springs. Blue front and yellow rear, or all yellow. I'm not sure about the Tamiya carpet tires, but with that spring and oil combination using comparable Sorex 28 or 32 tires, your basic carpet setup should work. I still have a 417v5 that I run on carpet with these settings and can do very well with it. 17.5 powered cars can run softer than the higher power motors as weight transition isn't as abrupt. If you're racing in cooler climates, drop the oil down to 35 or 37.5 weights. My oil references are for Associated silicone oil. You will have to try and see what works for your driving style/ track layout.

Also, look at the other carpet setups. On petit, look at Sean Williams's setup as I run the same track he did his car setup on.
Thanks so much! I'm glad that I can get closer to tuning my car properly.
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Old 04-09-2015, 08:28 AM   #6473
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Default 417 upgrade

Hi guys, would it be possible to fit a regular 417 to a 417v5 lower deck? If so, what other parts do i need to purchase?

Any other recommendationson the upgrades aside from getting a new 419?

Thanks
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Old 04-09-2015, 10:29 AM   #6474
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If I remember correctly, the 417 versions should all work with each other. I know I've put the first version components onto a smokem racing and exotek chassis plate. There might be a couple of motor mount screws in different locations down the centerline, but the important structural mounting points should be the same. All the suspension mounts are identical. I even have a 416we with smokem chassis that looks so similar to a 417 until you look at the motor mounts.

The V5 chassis requires that you get the single point floating servo mount though.

No need for a 419 just yet, the 417 is more than capable, unless you must have the latest and greatest or if you're a pro driver, and you notice all the nuances that you don't like about the 417. Highly doubt that will be the case....

The V5 chassis is still as competitive as anything else newer at the club racing level. I've even run my 416we against 2015 BD7's, TRF418/419, and ARC R10's, etc. Just don't expect them to run perfectly out of the kit's manual settings. They are good baseline starting setups. I've noticed many guys build them per kit instructions and say the car doesn't work for them, but they haven't spent much time tuning the suspension.
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Old 04-09-2015, 03:42 PM   #6475
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Sorry to intrude.

RC BOMBSHELLS is gonna have a 417 super bundle package coming up for grabs soon if anyone is interested. Coming ARTR with a lipo or 2. 2 painted sedan bodies and a NIB Mazda 6unpainted shell. This one is loaded and has enough plastic and aluminum (blue) spares (NIB) to choke a goat. Few runs and on a brand new chassis, priced at $500. Stay tuned for post in sell thread in the days to come.
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Old 04-10-2015, 02:03 AM   #6476
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Quote:
Originally Posted by greenpea76 View Post
If I remember correctly, the 417 versions should all work with each other. I know I've put the first version components onto a smokem racing and exotek chassis plate. There might be a couple of motor mount screws in different locations down the centerline, but the important structural mounting points should be the same. All the suspension mounts are identical. I even have a 416we with smokem chassis that looks so similar to a 417 until you look at the motor mounts.

The V5 chassis requires that you get the single point floating servo mount though.

No need for a 419 just yet, the 417 is more than capable, unless you must have the latest and greatest or if you're a pro driver, and you notice all the nuances that you don't like about the 417. Highly doubt that will be the case....

The V5 chassis is still as competitive as anything else newer at the club racing level. I've even run my 416we against 2015 BD7's, TRF418/419, and ARC R10's, etc. Just don't expect them to run perfectly out of the kit's manual settings. They are good baseline starting setups. I've noticed many guys build them per kit instructions and say the car doesn't work for them, but they haven't spent much time tuning the suspension.
Thanks for the input. Appreciate it!

So aside from the floating servo mount, is there anything else i need to purchase to fit my 417 into the v5 lower deck? I also heard that the 419 gear diff would be good to use on the 417 instead of the gear diff II. Any other thoughts?

I was thinking of going for either the smoke or raceberry conversions but unfortunately, I couldn't seem to find them in stock online.
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Old 04-10-2015, 08:39 AM   #6477
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Nothing else you'll need to purchase. I checked the chassis' this morning and the holes ALL line up on the lower deck for the motor mount. Only thing extra is the location tab and extra hole on the newer chassis' for the single point servo mount. Get the newer V5 chassis, it works great on carpet. The other aftermarket stuff is nice, but you'll have a harder time finding those now. Smokem doesn't seem to be in operation anymore since the beginning of the year.

As for the 419 gear diff... it's nice, but I've seen just as many of those leak as the gear diff II. You just have to build them properly and shim them so they don't leak. They're very smooth though when done well. You really don't need the new diff. It looks nice because it's black and the teeth are larger, which makes it more durable.

If you're planning on spending quite a bit of money, I'd tell you to go ahead and get a 419. The prices are dropping on those fast. They're about 90-100 USD more than a brand new 417V5 kit, as I saw this at a TCS sale. You'll spend quite a bit to get a chassis and motor mount to update the 417 to V5 status, but the motor mount is still different from the first 417 to the final version. That's another expense to update.

I would honestly advise you to just drive the 417 as-is and get more track time along with setup experience. I do not know your RC or track experience, but these goodies and updates won't do you much good if one can't drive the car well enough and be consistent with it. If and when one does get consistent, upgrade to a better car! You won't feel like you've wasted money to update the older car if you've only driven on it for a short time and finally decide to upgrade.
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Old 04-11-2015, 12:25 AM   #6478
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I bought this roller a month ago and I'm finally getting around to finish it
Having some issues
It didnt come with a servo horn. I have a few alum 25 horns but I can't seem to get any of them on top of my Savox 1252 servo.
It's wierd.
So I rigged a horn out of the junk that came with the servo
Problem is that I don't have much turning on each side
I have my spektrum set at 150% left and right but this is the max I can move the wheels
What's wrong?
Is my "horn" too short?

This video shows what I mean

https://youtu.be/rsrQwoKlkFE
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Old 04-12-2015, 12:53 AM   #6479
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Quote:
Originally Posted by macscac View Post
I bought this roller a month ago and I'm finally getting around to finish it
Having some issues
It didnt come with a servo horn. I have a few alum 25 horns but I can't seem to get any of them on top of my Savox 1252 servo.
It's wierd.
So I rigged a horn out of the junk that came with the servo
Problem is that I don't have much turning on each side
I have my spektrum set at 150% left and right but this is the max I can move the wheels
What's wrong?
Is my "horn" too short?

This video shows what I mean

https://youtu.be/rsrQwoKlkFE
Did you check the dual rate setting? Increase the dual rate.
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Old 04-12-2015, 03:13 AM   #6480
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Quote:
Originally Posted by macscac View Post
What's wrong?
Is my "horn" too short?

This video shows what I mean

https://youtu.be/rsrQwoKlkFE
With the steering rack centered and the servo in neutral, the centre line through the servo horn should be at a right angle (90 degrees) to the short turnbuckle that connects to the steering. This helps with even left/right throw and should be your starting point.

If you get this part right, but the steering is not quite straight, adjust the short turnbuckle, rather than use trim. As much as possible, this should be the natural "zero" position of the servo. The servo horn will be a few degrees from the vertical.

The attached drawing is rough and ready, but might help.

Phil.
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