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Rollers too tight? & other noob questions!!

Discussion in 'Technical Help' started by Reuben Herries, Nov 7, 2019.

  1. Reuben Herries

    Reuben Herries Spacer

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    hi Guys, just a quicky, in my local class I have just moved into the 'pro' class and can now use bearing rollers, but I can seem to get them to spin freely. I have cleaned them in lighter fluid, and tried putting a drop of oil back on but the seem slow.... Can you over tighten them if you use the correct washers?
    how long do they take to loosen up?

    Feedback welcomed! Thank you.


    upload_2019-11-8_9-38-34.png
     
  2. Reuben Herries

    Reuben Herries Spacer

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    Also, I am running 2 FM-A cars and a VS. and have just learnt about gear ratios (I had thought all standard sets would be the same ratios...) my question is how needed are the flouride shafts? and bearings in the counter gears? what is my first steps in transmission modifying??

    the VS has a 5:1 ratio so needs to change!
    thanks :)
     
  3. ltr74

    ltr74 FRP Popsicle

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    The 5 spoke plastic ringed are normally pretty good out of the package. I normally soak rollers overnight and shake the bottle a couple times to clean bearings. Sometimes rollers take a little running to get rolling smooth. Some are just always bad because of poor machining, poorly seated bearings or just a bad bearing. I'm assuming you don't have a bearing changer so just run it a bunch, clean them, repeat. Some will never improve.

    As far as your gearbox questions. Flourine shafts are a little better, probably not enough to see the difference but they are pretty cheap so not a bad thing to run. Bearings in the counter gear is also good, but not as much as some people think. Even with a bearing in the counter gear, there is a large amount of plastic still contacting the gear shaft. But again like the fluorine shaft, it is a small improvement.

    Some other improvements are again small but all the small improvements add up. There is a lot that can be done. Your best option is to watch through the VS series of videos from Mad Tang. They are old, but still helpful information and some of it can transfer over to the FMA chassis. The spacing is a little different between the two chassis but gives you an idea of what to work on.

     
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  4. Roscoe_tm10

    Roscoe_tm10 Spacer

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    You need to break them in first sir. There're so many ways to do it, but usually I use a motor and attach the shaft to the roller, hold the roller and then put some power to the motor so only the bearing inside of the roller that'll spin. You can also add some compound to smoothen the bearing movement
     
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  5. Reuben Herries

    Reuben Herries Spacer

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    ok, yeah sure. makes sense! thank you for that.... will try again :)
    Do you oil them or run them Dry? I have heard both!
     
  6. Feroce

    Feroce Screw

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    Sometimes where the ball bearing sits into the roller is too tight, if you have the possibility to remove the bearings try to work on the hole with some sandpaper. Something like this:

     
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  7. ltr74

    ltr74 FRP Popsicle

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    It's so helpful to be able to replace and reseat ball bearings in rollers. The only down side is the tools to do it properly can be difficult to get a hold of.
     
  8. Reuben Herries

    Reuben Herries Spacer

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    Thanks for the replies Men!!

    I pushed out and replaced one of the bearings as it felt rough.... but am unable to get them spinning freely still?! they're not bad but still far from great!

    I did take your advice and shortened the roller base length and have gone to the 13mm up front and 18mm at the rear.

    Racing is tonight so I will let you know how I get on! Tonights track is below: good track but the last jump before the final corner was the deciding factor.[​IMG]
     

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  9. Reuben Herries

    Reuben Herries Spacer

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    Does anybody use the rev tuned or Sprint dash motors and small wheel set up? it seems everyone uses Torque Tuned and Hyper Dash?

    Is the high reving set up and small wheel set up worth a try?? or stick with the higher torque motors? Most of our tracks are fairly technical with jumps and slopes.

    Thanks team :)
     
  10. ltr74

    ltr74 FRP Popsicle

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    Everyone fast runs torque tuned with the medium sized 26mm tires for tuned class here. In Open class everything from light dash , Hyper dash through Mach, Sprint and Power dashes are popular. For tire size, 23 to 24mm is very popular as it's the current trend in Japan though some people are sticking with the 26mm trimmed tires.

    We don't really change tire size depending on motor. Normally you set up your car with everything on it and then change motor depending on track layout.
     
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  11. Reuben Herries

    Reuben Herries Spacer

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    ok, yeah cool. I'd love to try all my thoughts and ideas, but don't have time and resource to get them all made, so this helps narrow things down! I race in a class close to tuned and am starting in open (but am not up to cutting chassis up yet!)

    thanks again ltr74
     
  12. Reuben Herries

    Reuben Herries Spacer

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  13. Reuben Herries

    Reuben Herries Spacer

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    Here is my (My kids) fleet of cars, trying to do our best on a budget!!
    Our best / most winning-est car was the Geo Glider, but that had a fatal crash last week on a speed track! so the MS Manta Ray II is a fresh build and un-tested.
    The VS Koala Racer is untested also, hoping to get to our local shop this weekend at some point.

    I cant manage to keep the MA Hawk Racer GT on track either? it has always had speed but seems to CO randomly? tried more and less thrust? but no answer yet

    Tips and feedback welcomed!

    thanks 78919200_2502661266667511_6870063243813978112_n.jpg
     
  14. ltr74

    ltr74 FRP Popsicle

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    I see cars like your a lot at the places here with tracks but without expert advice on builds. Here in the US, we have a class called tuned, which is kind of beginner to intermediate builds. While it may be different than what you run, looking at a tuned class car will give you a good idea of proper setups. This is one of my cars from a couple years ago. I don't really race tuned anymore and this example is a little old, but it will serve the purpose well.

    Screen Shot 2019-12-06 at 9.24.25 PM.png Screen Shot 2019-12-06 at 9.24.45 PM.png

    You should work on getting your cars to look something like this.

    Your Hawk Racer is not bad, change your rollers so the 12/13mm double rollers are on the bottom and then spacers up as stabilizer. You really need side mass dampers moved forward and not just on the little plastic wing thing. Get either AR side mass damper(the best because of the dampers that come with it) or the MA piece. This will push your weight forward giving the car more balance.

    On some general advice.

    Tires: Low profile super hard tires are your best choice on 99% of tracks for every car.. Right now they are available in a set with matte silver rims, they come in some kits(your baron viento has them) and in January will be available in a separate tire only package.

    Rollers: Unless you are going ball bearing rollers the plastic rollers that come with AR, MA and FMA kits are great. They are made of POM low friction plastic and spin very well. The 13mm that come in the tune up kits are not POM and are not very good. I would personally switch over to the kit POM rollers on every car and upgrade over time to ball bearing rollers one car at a time.

    Mass Dampers: Side(as far forward along the side as you can) and rear on every car. The Koala car can fit MA style side frp plates for mass dampers. Also, 25 or 30mm long screws for the mass dampers. It allows them their maximum amount of movement that way.

    Brakes: I use almost exclusively front brake sponge only and in the rear just a popsicle. More front brake will make the car more likely to land with the front lower than the rear. This helps guide your car back into the track and causes less crashing out.
     
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  15. Reuben Herries

    Reuben Herries Spacer

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    Awesome response! thank you so much. I tested yesterday, on a 3 lane, with a few jumps and a fairly rough track. Barron Veinto ran great. Hawk Racer was fast but still leaves the track occasionally.
    Koala Racer was having problems until I moved to a parallel roller set up on the rear. The manta Ray was running average, I will change that to 18mm rollers all round tonight.

    But I killed my Torque Tuned motor! will need another for the race friday!! Will re-read your advice and keep working.

    might re-think my front rollers all round.
     
  16. Reuben Herries

    Reuben Herries Spacer

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    Question, Running a high and low roller at the front Vs running the 13/12mm double and a non spinning stabilizer?

    I had presumed that this was a left over from when the rules only allowed 6 roller installations..... but you are recommending it OVER using a 13mm high and 13mm low??
    Is this a resistance thing or are they simply not needed?

    thanks again- I am enjoying talking this over :)
     
  17. ltr74

    ltr74 FRP Popsicle

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    For the Hawk racer, where was it crashing out and how? regular corner or slope?

    It's unlikely from a regular corner, if it is, the problem is front roller angle is not enough.

    On a slope, it depends on how it is jumping and landing. It could be the hard tires are bouncing too much causing it to not land well and crash out. Or jumping too nose up causing the car to want to go up and out of the track. Fix that by increasing front brake, either softer material or lower the front brake. If it's not jumping straight then it could be that one side of the front or rear brake is lower than the other side causing the car to not jump straight. In rare circumstances it could be something we have occasionally noticed with MA chassis. Because of the way the motor is oriented, when it lands the torque and stiffness of the chassis can actually cause car to bounce and flip over.

    You should definitely set up with two sets of rollers of the same diameter in the rear. It gives the best stability, either double 13mm or 19mm are most common.

    So the front of that tuned car features the 12/13 double rollers with a top non-spinning stabilizer. It was from right after the rule went to unlimited rollers, but a few other comments about it.

    The front of the car is angled. If you run 13mm top and bottom on the front, the top roller can meet the track first. This is not really desirable because the plastic track flexes most at the top of the track and can result in inconsistent runs. The bottom of the lane is much stiffer and more consistent.. Also if pressure is exerted on the top roller it can allow your stay to flex a bit reducing your front roller angle. Because of this you want your bottom roller to hit first.

    At the time of the picture of the car, the options for smaller than 12mm were very limited. We had heavy 11mm full ball bearing rollers and 9mm ball bearings that were lighter but a little small. The 10mm trimmed pink crown gear was a really good compromise with what was available. Today we have 13mm rollers trimmed down to 11mm that give us a better option.

    As far as tuning, running a non-rotating roller on top in the front gives you an option that will slightly slow the car when the front tilts a little bit. Even with having 11mm rollers as standard for the front of my cars, I have a few of the non-rotating stabilizers in case I need a small adjustment.
     
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  18. Reuben Herries

    Reuben Herries Spacer

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    awesome, thank you. I have ordered a couple of bits, and will change front set up as suggested :) Had not thought of the top roller being further forward.
    Brake set up is something I need to play with, front vs back brakes. some run rear some run both or just front! but as with anything that will come down to tuning!!
    thanks again.
     
  19. Reuben Herries

    Reuben Herries Spacer

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    Half way through the re-configure last night my son informed me that this is what we are now doing... He is happy for it to be experimental! ha ha love the fresh idea!
     

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  20. ltr74

    ltr74 FRP Popsicle

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    No problem.

    Tuning is something you learn over time, but starting with a well built car that runs consistently helps a lot and allows changes you make to actually show a difference in performance. I learn new little tricks and techniques all the time

    That is not a horrible idea your son had. the closer the rollers are to each other the faster the cornering should be. It is something I have thought about experimenting with in tuned but my focus on open cars has really stalled much tuned car building. One thing I would be worried about is when the car jump, the bottom of the rear roller could get stuck on the track wall. To deal with this, we run a car under guard. On the pictures I already posted you can see an FRP piece behind the rear wheel and in front of the rollers. It sits just lower than the screw for the roller and allows helps stop the car from hanging up. In this picture below, you can see how the under guard mounts on the chassis. Though in the build I am showing you it's not as necessary because of how I designed the rear roller and brake.

    IMG_4007.jpeg IMG_3695.jpeg
     

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