2021–NSR Formula 86/89

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    • #15743
      Avatar photoBarkingSpyder

      This is the head thread of the series discussion for 2021 – NSR Formula 86/89

    • #15744
      Avatar photoBarkingSpyder

      Athough not officially approved as a series yet, (@11/30/20) many members seem interested in the NSR Formula 86/89 cars as a 2021 series.

      The cars are available from many popular retailers: Pendle, Electric Dreams, CloverLeaf, LEB Hobbies
      CloverLeaf: White & Test $63 Decorated $70 (many liveries) Spares-limited
      LEB Hobbies: White & Test $70 Decorated $77 (many liveries) Spares- $1~2 higher than others
      Power Hobbies: White & Test $70 Decorated $75 – 85. Spares-limited
      Professor Motor: White & Test $70 Decorated $85 – 95. Spares-moderate
      Electric Dreams: White $75 Test $80 Decorated $90-100. Spares-extensive, some higher than others; many DECALS available for Test cars.
      PendleSlot: US prices are competitive with Electric Dreams. Liveries & Spares-extensive
      SCC – no current stock @11/30
      132slotcar.US – no current stock @11/30

    • #15745
      Avatar photoBarkingSpyder

      NSR Formula 86-89 REVIEWS

    • #15746
      Avatar photoBarkingSpyder


      Once this series has been approved and a series-manager confirmed; I think we should discuss wheel choices.
      During unboxing the rear wheels appear “tiny” and in fact the OEM wheels NSR5021(13d x 10w) have a 10mm diameter rim with a max OD of 13mm at the ribs. [Upgrades NSR5022 (13d x 13w), NSR5026 (13d x 13w drilled)] This is smaller than NSR’s legacy F1-rims, NSR5005 with a 14mm OD at the rib (12mm width).

      Several reviews of the NSR Formula 86-89 cars mention this size difference as having a potential risk of rear-pan contact with the track (in climbs/drops). Basically if the rear tires are trued under a certain diameter, the end of the chassis may drag against the track in sections that are not flat.

      It appears that the axle for the Formula 86/89 cars is the standard NSR sub-3/32 size[1]; and it appears larger OD tires would not interfere with the body, therefore it does not appear to be a hard *technical* reason why the NSR5005 14mm OD rims could *not be used.

      NOTE: We previously used these rims and compatible tires (5220) on the 2016 Formula series (the NSR wheels were the same dimensions as the AllSlots). So members who raced the Allslot race in 2016 may have some leftover spare wheels and tires.
      [1] NSR and Thunderslot Axles = 2.37mm (2.99/32in)

    • #15747
      Avatar photochapracer65

      My preference would be to use the stock supergrip tires.  I like having the Goodyear Eagle sidewalls, for more realism.  It would also save members from having to buy more parts, including inserts.


    • #15748
      Avatar photoporsche917

      I agree with Russell.  I would like to keep this series as stock as possible to give everyone time to get used to the cars and save some money.  I would suggest stock everything except screws, braid, motor wire and gearing.  People can choose to upgrade the front and rear wings for the bendable versions but that is it.

      Gearing could be an issue as NSR only produces the stock black 27th as well as a 25t and a 24t in-line crown gear.  I don’t know of anyone who manufactures an in-line crown gear for the NSR axle diameter.  I have not run the cars so I don’t know if the stock gear is adequate or if a lower gear is necessary.  It’s crazy that there is not a 26t crown available from NSR.

      I would vote for everything stock except for:  1) a specified tire for front and rear, 2)body and pod screws open choice, 3)braid open choice, 4)motor wire open choice, 5)any NSR crown and pinion gears.



    • #15749
      Avatar photoALEREAL3D

      I will love to race the F1 myself if decided by the majority to schedule the race later in 2021


    • #15771
      Avatar photoBarkingSpyder

      In general I agree with the “stock” spec, except with the chassis clearance issues I mentioned above. Tire issues seem to be a recurring challenge and while I don’t want to have a situ. where people are spending a fortune on tires to be *competitive … we have had more than one series where many of us did spend lots of money trying to get good sets of tires, just so our car was not a dawg spinning on marbled or nippled rubber.

      In this case, if the tires wear down to a point where the pan is contacting the track, I don’t want to be replacing tires every round (or every other round).

      I would like to get input from John and Dave and whoever else actually has a 86/89 they can test and provide solid feedback.

      Gear Options:
      OEM 27/10 = 2.7 21,400/2.7 = 7,926
      24/9 = 2/67 = 8,015
      25/10 = 2.5 8,560
      compared to a hypothetical 26z crown
      26/10 = 2.6 8,231
      26/9 = 2.89 = 7,405

    • #15772
      Avatar photoporsche917

      I know we have all but finalized the decision to run the NSR F1 series due to the time they have been in market and the availability of cars and parts and I am all for running the NSR cars but this was posted today on Policars Facebook page.

      • #16993
        Avatar photoRadial TA

        I’m glad we decided on NSR.  I also bought a  Policar to test, but only swapped the chassis today, long after the decision was made to run NSR.  The wires to the guide are quite a trial to get from inside the body to the guide due to tight clearance.  Here is a picture of the two on the track today.  Quite a possibel 1/32??? debate.


    • #15797
      Avatar photoBarkingSpyder

      Another oddity[1] with this car is:

      As you will find out, the front axle height grub/allen screws are M2 (2mm diameter, 2mm length same as Slot.IT) and not the typical 4-40 (0.05 wrench head[2]) screws. Your car may come with a small bag containing the M2 screws.
      There does appear to be enough meat to drill and tap the axle carrier section to use 4-40s.

      [1] Other variations from NSR traditions: [a] 13mm diameter (at the rib/nib) wheels vs. the 14mm already in NSRs product line; –new tires to fit the new size wheels. [b] (as mentioned by 917) crowns are limited to 24, 25, 27 (missing a 26z?!)
      [d] flexible/no-tear/crashproof parts do Not include the front suspension?!? // the good news is this part is cosmetic and does not contain the axle carrier./

      [2] Diameter: 0.112inch * 25.4 = 2.84mm

    • #15799
      Avatar photoBarkingSpyder

      PCAR07 Generic Modern F1; $65 pre-order
      [1] Contains the multi-stage ‘transmission’ to allow a FF motor to be installed under the svelte body.
      Similar to existing Policar and Scalextric drive trains.

      Inline FF slim-can 25k motor (same size as existing Policar and Scalextric Formula cars)
      Drive Train: 9T brass pinion / 25/16T plastic stepdown / 17T brass crown
      Wheels – 11.5x20mm fronts, 14.5x20mm rears
      Wheel base 108mm Weight 58g

      — pretty, modern shape, includes halo
      — FF motor with 1.5mm shaft, can be downgraded (18k) or upgraded (30k) with motors from ScaleAuto, Scalextric, Policar, Professor Motor
      — Motor not similar to our other series.
      — Based on my experience with the FF motors they are not always very available (lots of Not In Stock)
      — 1.5mm Motor shaft has limited Pinions available (but 1.5 to 2mm sleeves are available)
      — Wheels and tires may have very limited upgrades or alternatives
      — Perhaps would need to be closed Brand series/class; may not be competitive with the NSR or AllSlot formula cars.

      Rear Wheel RPM Estimates
      25,000 / (25/9) = 25,000 / 2.7777 = 9,000 //25,000*(9/25) = 25,000*0.36= 9,000
      9,000 * (16/25) = 9,000*0.64 = 5,760
      5,760 * (17/16) = 5,760*1.062 = 6,117 ?? REAR WHEEL

    • #15801
      Avatar photochapracer65

      About the rear tires of the NSR Formula cars, I don’t see a problem with the stock assembly.  There seems to be plenty of  clearance out of the box, although I have not trued them yet.  There is much more clearance than with the Thunderslot cars.  Unless the tire formula has changed, there is a lot of history with the NSR Supergrip tires; we have used them in the past, as well as the softer Ultragrip tires.


    • #15803
      Avatar photoporsche917

      The stock tires have plenty of clearance even after truing.  NSR’s SuperGrip tires have always worked well on our track and in some quick testing of my car I don’t see any reason to spec anything other than the stock tires.

    • #15810
      Avatar photoBarkingSpyder

      NSR Formula 86-89 – Setup Phase-1
      Sat Dec 12 I unboxed my NSR F 86/89 to see what challenges may be in the setup process.

      GUIDE – the OEM guide is snap-in and has a short blade. I took out the slop with two Teflon spacers; during testing the guide performed fine.

      Tires and Wheels: The good news, the tires are heavy enough that nose ballast does not appear to be needed. The bad news, they have the typical NSR molding blisters, which may not be able to be totally removed from truing. The NSR Wheels use a 2.37mm (2.9858/32 inch) axle and hence I could not fit them on the large $400 double-truer.

      I took out the fore-aft slop using 3mm axle sleeves. At first I tried some Slot.IT spherical bushings; they had a groove to snap into, but had resistance sliding vertically and did not stay in the uprights consistently. Bad News: The axle uprights are noticeably angled in (negative camber) which may add some binding.

      Axle Height:
      The axle uprights use M2 allen/grubs for axle height. These are Not the typical 4-40/3mm grubs used in other NSR chassis. The shipped 2mm(L)x2mm(D) screws are tiny so I threw them into my collection of Slot.IT grubs. I used 7mm SlotCarCorner oval-head M2s for the bottom adjustment (5 or 6mm would also be Fine); and 4mm for the uppers. The fit is *tight and takes patience to get the screws deep enough.
      On my setup block, in the 0.015 cut, I flew the tires 1/2mm over track-height. Since our track is not perfectly consistent I cross-checked the height with my 0.025 cut, and they flew appx 1/4mm above track-height.
      NOTE: The holes are very tight and a 0.91m torque-wrench may ratchet before you reach the desired depth. I had to use my NSR solid-shaft 0.91. The axle height process took at least 15 minutes to reach Goldilocks status.

      I pro-actively bought the no-tear flexible parts kit. I can’t really see any difference between these and the OEM wings; so I left the wings alone. The body parts are “electronically welded” and appear very secure. Only problem, if they come off in a wreck the anchor posts will come off with the part.

      Round Steering Wheel
      As some have noticed, the steering wheel is disappointingly a spindly generic round version. Some people may want to scratch-build a steering wheel from styrene, or suitable static model rectangular parts.
      I don’t think there are many cockpit part kits with modern F1 steering wheels – for Scalextric or Carerra. AllSlot used to have a cockpit parts kit; but these don’t seem to be available.
      ?? Maybe Russ or Marc can make some up? : )

      The OEM gears seem to have a good mesh and are noticeably quiet. The calculated rear-wheel-RPM is 21,400/(27/10) = 21,400/2.7 = 7,926 @12volts.
      Other Gear Options: 25/9 = 2.78 = 7,698 24/9 = 2.67 = 8,015 25/10 = 2.5 = 8,560

      Again these use smaller wheels (13mm Dia) than the ‘standard’ NSR F1 tires offered as replacements for other brands. Visually they still look very similar in size. Because of the smaller axle I could not true them (yet) – surprisingly they were relatively True out-of-the-box and handled very well.
      Minor Issue: The sidewall brand letters flake off quickly.

      At 11 volts the car was very stable in the corners; but the speed felt “sedate”. With a calc’ed wheel RPM of 7,266 (7926 x (11/12)) the perception seems spot-on.
      At 12 volts the car was still very stable; and it’s overall speed seemed moderately faster than at 11v, yet not as dramatic as would be expected with a jump from 7,263 to 7,923 RPM. Best laps were 4.3-4.2 but that should improve with trued tires and after everything else is “broke-in”.

    • #15884
      Avatar photoBarkingSpyder

      The stock/OEM Formua 86/89 tires are very tight out-of-the-box; they do not seem to require gluing.

    • #15897
      Avatar photoBarkingSpyder

      Scalextric has “Detail Parts” and “Accessory Packs” for $3usd that contain a F1 style wheel with painted buttons (incl in the pack are a drivers head and mirrors). Electric Dreams have about 6 packs, PSR has about a dozen. They match Scaley modern F1 liveries, so you should find one with a color compatible with your car.
      P/Ns include: W8450 W8693 W8739 W8848 W9048 W9137 W9361 W9531 W9532 W9714 W9715
      Scalextric F1 Steering Wheel

      Carrera F1 Bodies have a more accurate Square Steering Wheel:
      These are not painted and are not offered in repair part kits; they have to be harvested from old bodies. Some are on shafts
        Others have small 90deg hook. You have to pop out the driver/seat partially to pop out the wheel assembly.

      Carerra F! Steering Wheel with hook

      • #16772
        Avatar photoDatto

        Mark, in 1986/89 from what I can determine, F1 steering wheels looked pretty normal.

        Here is a 1988 McLaren cockpit.

        [attachment file=”16773″]

    • #15939
      Avatar photoDatto

      Rule revision needed for mandatory sidewinder arrangement,and
      “ Wheel/tire must not protrude outside of the body when viewed from above, no exceptions – this includes axle float.”

      Realize this is copied/pasted.

      Marc T

      • #15943
        Avatar photoStabnSteer

        I found that this made me laugh heartily since the wheels are automatically outside of the body. But I think I get what you mean…  🙂

        Given these are essentially a spec body and chassis, we should have a specific measurement of how wide things can be. Get rid of the guesswork related to eyeballing.

    • #15946
      Avatar photoRadial TA

      And quit calling the fancy pattern on a tire the “thread”.  It is TREAD.

    • #16051
      Avatar photoBarkingSpyder

      Rules have been updated from the rough ones cloned from 917 coupe rules – hence the body and tire rules that did not make sense.

      Note: Some rules across many of our series have been copied from other clubs that raced similar series and had rules that make sense in the UK or Australia, or for sponge tires (e.g. oil soaking) or legacy cars (e.g. wires controlling front axle height) or 1-24 (e.g. guide cannot be visible beyond the splitter).
      Over the years some weird rules have been weeded out but others linger – LOL

    • #16052
      Avatar photoDatto

      Indycals has a nice range for F1 liveries of the period. I’m sure they can be made to work.

      Indycals F1

      Mark’s idea about an IM driver with decent wheel in intriguing. Will be looking into that.

      Marc t.

    • #16053
      Avatar photoporsche917

      I absolutely love the work Marc does with Immense Miniatures but didn’t see any modern-ish F1 drivers heads in his line up.  I have already purchased a driver head replacement for my NSR F1 car from Electric Dreams.  They carry a line called Interlagos Miniatures that produces pre-painted period correct F1 and Indy helmets that work great on the NSR F1 cars.  Worth checking out to improve the look of your car.

    • #16061
      Avatar photoBarkingSpyder

      Atalaya Decals ADF119 NSR Formula 86/89, Rothmans (ADF119) = $12.99
      Atalaya Decals ADF120 McLaren Marlboro, Keke Rosberg (ADF120) = $12.99
      Atalaya Decals ADL0802 Red Bull = $7.99

      (water slides)

    • #16067
      Avatar photoBarkingSpyder
    • #16335
      Avatar photoDatto

      I ordered a set of decals purpose built for the NSR F1 86-89 cars from LEB Hobbies. They almost fit on the test car. Had a devil of a time getting them to conform, but this may because my setting solution is old.

      BTW, Mission Models paint takes some getting used to, but I think I may be able to work with them.

      [attachment file=”16336″]

    • #16338
      Avatar photoDatto

      So, I’m calling dibs on #6 🙂

    • #16533
      Avatar photoRadial TA

      My decals arrived from England and the numbers are 3 or 4 not the 6 and 7 originally indicated.  So I want my number to be either 3 or 4 to allow the single digit number on the nose.  Anyone already using 3 or 4?

    • #16662
      Avatar photoBarkingSpyder

      POLICAR F1 Monoposto Trivia
      I posted a detailed analysis of the Policar here: 15799
      I recently got the Green Benetton livery from Kings. I will post a “unboxing” review soon.

      To find other information on these cars:
      Unboxing and Basics – Home Racing World   ;   Cincy Slots

      Axle Tuning (Dave Kennedy)

    • #16670
      Avatar photoBarkingSpyder

      Dave is Series Manager for F1 – but for this year, we are NOT planning to race the Policars against the NSR F1 86/89s.

    • #16688
      Avatar photoBarkingSpyder

      Simple Solution to excessive NSR Crown Channel and Pinon Wear (paraphrased from Russell’s email)

      The OEM brass axle spacers on the outside of the motor pod bushings reduce movement of the crown gear “landing” or “channel” for the Motor shaft.  With the spacers against the bushings on one side and the wheel on the other, the axle has very little side to side play. The crown can then be set-screwed in the proper location for best gear mesh.
      Additionally: you can trim the Motor Shaft to prevent Any contact with the channel on the crown.
      ALTERNATELY:  “Axle Stop-Collars” like the one below the chassis in this picture, can be used on both sides instead of the brass spacers. The effect is the same, except the Stop-Collars must be carefully adjusted with an allen wrench to prevent too much friction with the bushings.

      Spacers and Collars

      After having major wear issues with the NSR aluminum-collar crown gear last week in practice, I installed a NSR crown gear with Brass collar. One thing I see is that the Valley-depth of the NSR crown gears (alloy or brass) forces the motor shaft against the left flange of the crown. That’s why the aluminum crown was so worn even with lots of grease. After carefully moving the pinion to allow clearance, it appears to work ok after about 45 minutes on the test roller. The brass NSR crown gear shows signs of gear teeth slightly binding as it did with the aluminum gear. Are other racers having the same issues with your NSR F1 gears?

      I also tried a Slot.IT Brass-collar crown which is only .001 larger in axle diameter than the NSR. I ran the Slot.IT crown gear on the roller for 30 minutes at 4 volts. The fit and mesh seem far better than the NSR. See no vibration or out of round issues with the Slot.it gear.
      I will put it on track next week. If it works, I would like to Propose the rule allow Slot.IT crowns.
      I want the F1 series to be successful.

      Lotus Jr.

      Shaft rubbing channel

    • #16689
      Avatar photoBarkingSpyder

      John – please post a picture of your rollers/rolling-road !

    • #16690
      Avatar photoDatto

      Interested to know what alterations we will be allowed make to forestall failure of the crown gear hub. I replaced my crown with a brass hub NSR piece, because of Aluminum’s propensity for galling.

    • #16691
      Avatar photoporsche917

      At this time I would say it is up to the series manager to decide whether or not the Slot It crown gears are allowed.  Please post any concerns here so David can review them.

    • #16692
      Avatar photochapracer65


      The issue with the stock crowns is the wearing of the channel for the motor shaft, right?              (too tight? too binding?)  Or is there some issue with the mesh itself?  If it is the wearing/friction, then cutting off the end of the motor shaft and adjusting everything tightly, without too much side axle play, would seem the simplest solution.  Assuming that would be legal…..  I have not had a chance to run my car at all, but that is probably the first thing I would try.



    • #16695
      Avatar photoBarkingSpyder

      from John:  1st – reference: Post-16688

      1 The shallow depth of the NSR crown teeth, presses the motor shaft disproportionately against the Thin (0.50mm) “guard-flange” of the Centering Channel.

      2 With the Aluminum shank crowns, the guard-flange wears quickly, shedding AL dust and distorting the shape of the Centering Channel.

      3 After less than an hour (on a rolling-road) the crown’s mesh has changed (the teeth are alternatively pressing harder/loser against the pinion). Friction increases noticeably.

      4 The NSR brand Brass/Bronze shank crowns take over 45 minutes before they start shedding from wear on the guard-rails. The NSR Brass/Bronze crowns also have a (0.50mm) guard-flange.

      5 The Slot.IT brand Brass/Bronze shank crowns have a (0.75mm) guard-flange. After 30 minutes on the rolling-road, the Slot.IT Brass/Bronze crowns seem to have little shed, and NOT degrade in mesh/lash (and hence performance.) The slight eccentricity from the Slot.IT having a larger diameter hole 2.38mm (2.998/32 inch, 0.09370in) vs. 2.37mm (2.9858/32 inch, 0.09331in) for the NSR axle, does Not seem to have any obvious consequences.
      6   Russ’ solution to use the OEM brass spacers, and Trim the shaft so that it no longer contacts the Centering Channel – seems to be an easy and viable solution.

      from Mark:
      The wear issue appears to be either a flaw in the Design of the Crown’s teeth (too shallow) or in the Manufacturing during alignment on the Shank (computer parameters mouning the crown on the shank too close to the centering-channel). The skinny 0.50mm Guard-Band also seems like a Doofus design choice with no apparent cost/weight/performance benefit. Note that most NSRs are either short-can pseudo-sidewinders (2deg AW) or long-can angle-winders; so their overall experience with Inlines seems limited (e.g. only ocurrent models with ILs are Mosler, Clio, Abarth, LMP, F1)
      In conclusion – I join John in (a) requesting that both (a) the Slot.IT crowns (b) and trimming the motor shaft be Permitted.

    • #16783
      Avatar photoBarkingSpyder

      Marc – thanks for the technical/historical update : )

    • #16788
      Avatar photochapracer65

      I agree that stop collars can produce more drag, but they are not the only option.  Attached is a photo of my Jaguar lightweight that I built four years ago.  I am doing some work on it.  I originally had two stop collars on it.  I put a .005 Slot Car Corner axle spacer, then a .100  axle spacer on the outside of the motor pod, opposite the crown teeth.  This limits the axle side play away from a tight gear mesh.  The original axle collar is still located behind the crown gear, but it no longer makes contact; the .100 spacer is the limiter.  I will probably be removing the collar.  Although not totally necessary, I will probably put a spacer on the other end of the axle that will limit the axle play toward tight gear mesh.  That way, instead of side load to the crown gear, the side loads will be to the two axle spacers.  Once adjusted there will be no more drag than axle spacers.  I will see how it works when I have a chance to test it.


    • #16790
      Avatar photoporsche917

      Nice work Russell.  I agree with your assessment of axle collars.  I’m going to try running without them to see how it goes.



    • #16796
      Avatar photoBarkingSpyder


      “This is basically what Russ described, a nice how-to video from NorCal ”  Marc/Datto

    • #16798
      Avatar photoBarkingSpyder

      RUSS – where did you get the 3DP motor pod with adjustable off-set? Is it easy to adjust?

    • #16836
      Avatar photoporsche917

      Are we allowed to put nail polish or other compound on the front wheels to lessen the grip?


    • #16841
      Avatar photoBarkingSpyder

      I would like a ruling from the Series Manager.  There are now several tire/wheel options from NSR for the F1-86/89.
      OEM/original (19.5 X 13) NSR-5284 (Supergrip 25shore?) 5284 (Ultragrip 15~20shore?)
      Alternative (19.0 X 13) NSR-5287 (Supergrip) 5288 (Ultragrip)
      Both 19.5 and 19 OD fit the NSR F1 wheels with a 13mm Diameter Rim/bead.

      FRONT TIRES: NSR-5290 (16X8) NSR-5291 (17X10)  Zerogrip (fit the same wheel-5020)

      REAR OEM NSR-5021 have an “air-system” Rib/Nib. 13mm OD x 10mm width
      NSR-5027 –  Solid Rib/Nib. 13mm OD x 10mm width
      NSR-5022 -“air-system” 13mm OD x 13mm width
      NSR-5026 -“air-system” Drilled – 13mm OD x 13mm width

      FRONT OEM NSR-5020 solid Rib/Nib. 13mm OD x 8mm width

    • #16857
      Avatar photoporsche917

      I would suggest keeping the rules for the cars as stock as possible.  I don’t see a need to upgrade or change wheels or tires as the stock ones work well.  This will also help keep costs down.

      Having said that, the crown gear could be another conversation.

    • #16866
      Avatar photoBarkingSpyder

      The calculated rear-wheel-RPM – OEM @12volts:  OEM ratio 21,400/(27/10)
      = 21,400/2.7  >  7,926 **

      Other Gear Options: @12volts
      24/9 = 2.67  >  8,015 **
      25/9 = 2.78  >  7,698
      // not really usable at 12v
      …27/9 = 3.00 > 7,134;    …25/10 = 2.50 > 8,560;    …24/10 = 2.40 > 8,917

      @11volts  OEM ratio 27/10 = 21,400(11/12)/2.7 = 19,617/2.7 > 7,265
      24/10 = 2.40 = 8,174 **
      25/10 = 2.50 = 7,847 **
      …24/9 = 2.67 > 7,347;   …25/9 = 2.78 > 7,056;   …27/9 = 3.00 > 6,539

      OEM NSR 6327AL 27 tooth black crown, Aluminum shank
      NSR 6324BR – bronze/brass shank
      NSR 6325BR
      NSR 6327BR

      OEM NSR 7010-10 tooth “easy” pinion. 5.5mm OD
      NSR 7009-9 9 tooth
      NSR 6809-9 Lightweight
      NSR 6809-10 Lightweight


    • #16876
      Avatar photochapracer65

      Gear Pitch

      Ary wrote a terrific article on gear pitch 10 years ago that everyone should read:  http://austinslotcarclub.com/forums/topic/gears-pitch-mesh-a-look-into-slot-it-variable-pitch-gears/

      With the diameter of Slot.it pinions fixed, the pitch varies with the number of teeth, while all Slot.it crown gears have a fixed pitch of 48; their diameter changes.  For that reason, the optimum Slot.it gear mesh is achieved with an 8 tooth Slot.it pinion.  9 tooth is OK too; 10 tooth is marginal, and 11 tooth should be avoided.  I do not know the pitch of NSR pinions and crowns to know how they compare to the Slot.it gears.  The pitch of the NSR gears can be calculated by using the formulas in Ary’s article.

      This is a separate issue than allowing Slot.it gears in the NSR cars, but if anyone does so, the pitch should be calculated to see how well disparate gears will mesh.


    • #16877
      Avatar photoBarkingSpyder

      The Pitch of the NSR Pinions, Crowns and Spurs are in the ’48’ range.

      This is quite common in 1-32 scale gears. The tooth shape of the smaller Pinions is like a tulip or a vaulted-arch. As the tooth count increases, the shape morphs to an “I”. On the drive (Crowns, Spurs, Contrate) the tooth shape is mainly a straight sided Triangle. On Offset Crowns the teeth become slanted so they can mesh easier with the pinions non-angled teeth (similar to a 1×1 differential gear).

      Whereas in the current 1-24 world, “Coarse” gears are 48p, and “Fine” are 72p.
      yet – the most popular in current 1-24 land is 64p (medium) since it has a finer-Lash than 48p but does not Shed as fast as 72p.
      If the pitch gets “too fine” (e.g. thin “A” shaped spikey teeth with “V” valleys) they can strip very easily by gunning the motor or during a crash that impacts the tire/wheel assembly (e.g. the motor grinds the pinion into the plastic when the wheel stops after hitting another car or the Wall).

      Hence – in the 2021 NSR Catalog (pg27) you see a 8z(teeth) steel pinion (#7408) with a longer “hub” and 64-pitch rating. That pinion is designed to be soldered onto a 2mm motor shaft and meshed to a 64p Spur (flat or 5%-beveled); mounted in an Angle-winder orientation (pinion on left side; clockwise/righty rotation).

    • #16878
      Avatar photochapracer65

      I was a little slow to process the data.  Since the Slot.it and NSR pinions have the same diameter, each pinion will have the same pitch as their counterpart in the other manufacturer.  Eight and nine tooth pinions will have the best gear pitch; ten and eleven tooth pinions should be avoided.


    • #16879
      Avatar photochapracer65

      I had forgotten about Ary’s followup on NSR gears.  It just goes to show how much information is in ASCC files.


    • #16880
      Avatar photoBarkingSpyder

      Russ – I had to double-check myself to make sure there were tables for both Slot.IT and NSR. And – to your point we have some Great assets; I always stumble across a reference to one of Ary’s How-To videos or one of our Forum posts when searching the interweb for slot-car 411 🙂

    • #16897
      Avatar photoporsche917

      David posted on the home page – I spent a lot of time Saturday running my F1 with new NSR gears had no problem it ran very smooth. NSR gears is what we will use for this race.

    • #16962
      Avatar photoBarkingSpyder

      AS OF THE CLUB MEETING 9/25 – the members present voted Aye/for and David approved the use of the Slot.IT inline crown gears.

      MANDATORY:  Slot.IT crowns can only match the tooth-count(z-number) offered by NSR;

      24, 25, 27

      RPMs: using the stock 10z pinion: at 11v:  27/10= 7265  25/10 = 7847 24/10 = 8174

      RECOMENDED: Brass/bronze vs. Alloy/aluminum   // brass seems to wear less.

      Important Note:  NSR motors are setup to turn Counter-Clockwise (lefty) vs. Slot.ITs which turn CW/righty – looking at the motor from the pinion end.  If you install a crown with the plastic gear bed on the right (looking at the pinion end) the car will run Backwards, and you’ll notice a slightly smaller/tighter open area in the gear box.  DO NOT ‘fix’ the problem by swapping motor wires – you are now messing up the Advance (deg.) the motor has built into the Armature.  You are also now running the armature backwards (from any break-in from the factory or when you prepp’ed it).

      Some 4-40 grub screws are a little too long in the arbor/collar of the gear and can hit the motor or pinion.

      /**  To Series Manager Dave  Cass and ASCC members; my sincere thanks  for accepting  the proposal to run Slot.it crown gears as an option to the NSR gears for the F1 series. These gears will make the F1 car smoother and more reliable.  Ran over 200 laps today with no issues.   Tip: Have added significant weight.  These cars in the right hands are sub 3.8 possible.   John/Lotus-JR **/

    • #16963
      Avatar photoBarkingSpyder


      Using a green ultra-hard chassis, the holes for the top Axle-grubs were tight and useful – for M2 allen grubs.

      BUT the Bottom holes were so loose, I had to carefully drill a hole large enough for a 4-40 (the typical NSR grub screw) and installed the brass upgrades.  CAUTION there is barely enough ‘meat’ in this area to allow the 4-40s.  This was only My experience and fix; “your mileage may vary”; “caution – coffee is hot and should not be placed between your thighs”; “don’t take stellara if you are allergic to stellara”.

      ESSE TURN CLIMB – the climb-out likes to porpoise the car out of the slot when entering the back ‘straight’.  A 1/2-mm to 1-mm flying gap with a slight bit of axle slop seems to prevent the Pop-out.  3/4 to 7/8 mm was the range my particular car seemed to “like”.

      I also added a 3 gm lead disk behind the guide.


    • #17006
      Avatar photochapracer65

      Front Axle Grub Screws

      I had the issue with the lower front axle grub screws not holding in the chassis; the grub screws would just spin.  I took several strands of copper guide braid (maybe 6 or 7 strands), twisted it together and put it in the grub screw hole, with the end of it sticking out, and screwed in the grub screw.  This seemed to make it hold.  It stayed firm through the race last week.


    • #17007
      Avatar photoporsche917

      Russell and All – The NSR replacement chassis’ I received run two different grub screw sizes.  The lower grub screw is the standard NSR sized grub screw while the upper one is a Slot.it sized grub screw.  When installing the lower NSR grub screw it feels like it’s too big and will break the chassis but they do fit.  The chassis will budge out a little but that is the correct grub screw to use.  There are no issues with the upper grub screws.

      I don’t know if this is consistent with all the chassis but it is for the three replacement chassis I received.  Of the three chassis I purchased – one green and two white – the green one did not come with grub screws but both white ones did.  The screws that came with the chassis were two different sizes.

    • #17012
      Avatar photochapracer65

      So is the “standard NSR sized grub screw” the NSR 1238 M2.5 grub screw or the NSR 4809 M3 grub screw?


    • #17013
      Avatar photoBarkingSpyder

      Officially, NSR intended these to be M2 (i.e. 2mm diameter) holes, hence the useless 2mmL x 2mmD  (b/c they are Too Short) pack of M2s that should be included in your jewel case.

      IMHO – this decision makes no sense from NSR (e.g. does not really make the chassis “uglier”, or lose performance, to make the uprights fat enough for their typical 4-40 screws).

      My first black/medium chassis accepted the M2s and I have SCC 4mm Oval-heads on the Top and Bottom.

      PER MY PREVIOUS POST #16963, on my Green/X-Hard chassis the top axle adjustment screw holes *were* tight enough for M2s, yet the Bottoms were loose, forcing me to use 4-40 brass grubs (very carefully).

      NOTES  My new LEB Hobbies car, has wide bottom holes (needs m2.5 or 4-40).  Yet – I have another spare black chassis that Is Tight Enough for the M2s (WTH?)

      For the bottom – if you have M2.5 grubs (from Thunderslot?) they *may* be the perfect solution.

      Otherwise you may want to TRY USING 4-40s  (i.e. normal NSR, i.e. use a 0.50 wrench).

      The English bit size is:  7/64  (i.e.  0.1094)  which is just small enough that the 4-40 (i.e. 0.1120) can Bite into the plastic and hold.

      Using the 4-40, you will see the stretch-marks, but unless you are ham-fisted the risk of damaging the chassis is Moderate.  Take it slow and careful, one side at a time.

    • #17074
      Avatar photochapracer65

      New NSR F1 rule

      A new rule has been added to the NSR F1 Race Rules Page.  Maximum overall axle/tire width is 68mm.  This will be the limit for both rear and front axle/tires.  I hesitate calling it a track width because, usually, track width (at least on 1:1 cars) is defined as the width, wheel center to wheel center.  For our purposes we measure the overall width, which will be sidewall to sidewall.  There was no max width specified in the original rules.

      With cars with enclosed bodies, the maximum width is limited to the width of the body (and adjustments made if a car’s body is out of scale).  With open wheel cars, we should probably always have a max width specified.

      This new rule will be implemented with NSR F1 race #3; the results of the first two races will stand, as they were raced with the rules at the time.

    • #17076
      Avatar photoBarkingSpyder

      Thanks Dave, Russ, Marty

    • #17145
      Avatar photoRadial TA

      Getting the rear track (tire wall to wall) out to 68mm yesterday was quite a trial finding the right combo of spacers.  I am hoping it was worth it.  I did also change the front tire/wheel combo to the optional setup.  This car could have been an excellent class strictly out of the box, as shipped, and save your time and energy instead of all of the mods we are making.  rant completed.

    • #17146
      Avatar photoporsche917

      Randy – I agree with you.  It would have been good to just keep this as stock as possible.  There is always next time.


    • #17147
      Avatar photoDatto

      [postquote quote=17145]

      For some of us, the puttering is a big part of the fun.

      [attachment file=”17148″]

    • #17151
      Avatar photoporsche917

      WOW!  That is a whole other level.  I like what you are working on.  I think you and Russell are the masters at that type of work.  I am always impressed with the quality of work you both create.  Impressive.

    • #17154
      Avatar photoBarkingSpyder

      #17145 “…Getting the (tire wall to wall) to 68mm yesterday was quite a trial…”

      REMINDER: the 68MM sidewall-to-sidewall *is* the out-of-the-box spec; as a Limit, Not mandatory minimum.
      RULES: have been on the site since January and do not require changes; just Allowed options; and this summer we allowed the Slot.IT crown gears to avoid problems reported by at least one racer. Discussions have been open since January.
      Anyone can ran the car stock-as note in #5810 PERFORMANCE, they in general run fairly well out-of-the-box.

    • #17155
      Avatar photoBarkingSpyder

      #17147 – this note is not germane to the F1 discussion, but I echo Marty. Marc – it would be very cool if you brought some of your projects to ASCC and gave us a “demo” of how to create a body from wood, or how you create a Buck from wood to use for resin or 3DP bodies.

    • #17157
      Avatar photoBarkingSpyder

      #17145 – ” .. This car could have been an excellent class strictly out of the box, as shipped ..”
      Randy, perhaps the Policar F1 would be a good future candidate for “box-stock” because the reality is that other than the tires, there is Not much at all you can actually change with the Policar modern F1s.

      Performance would not match the NSR F1, but it would require significant driver skill to counter-act the engineering and handling challenges of the stock configuration.

      Hence – a Policar F1  “drivers series” would be a fun challenge 🙂

      Perhaps you can propose a future “box-stock” series, and be the Series Manager 🙂

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At 4-years old in Pensacola I repaired my steering linkage on my Ford Pedal-car. Dad later converted this car to a Blue Angel with ailerons and elevators with a working "stick/yoke"; the rudder was controlled by the steering wheel. I like all motorsports - I grew up going to a NASCAR Feeder track with Sportsman and Modified classes, and was lucky to attend drag races in 1970 at Orange County Raceway. My first solder-iron was a Christmas gift at 9yo; I modified T-Jets to be AFX spec before AFX Cars were in local stores. I rebuilt a few tractor & car (SIMCA) engines plus transmissions by 15yo (I still have my ring-compressor and valve spring tool) I am a former mountain and road bike geek & perennial sound engineer. Struggling guitar hobbyist and Amp "tweeker"