Pinion pitch for Tamiya

[jozza 1]

The pinions for my touring cars are 48dp, and I've seen mentioned that the Tamiya pinions are 32dp, but the only pinions I've seen apart from 48dp are marked as 0.6 module [?]

Can anyone tell me what the "dp" stands for, and explain what the RW 0.6 module pinions are?

Would these be the correct ones for the tamiya cars (specifically the Twin Detonator)? I would buy the genuine Tamiya ones, but they only seem to come in pairs of different sizes, and I want 2 20T ones, so I don't want to have to buy 2 that I would just throw away!

Thanks!

[sosidge 624]

dp - diametric pitch - a measurement of the size of the teeth. It's an imperial measurement, and it tells you how many teeth would be on a gear of 1-inch diameter (48dp = 48 teeth on a 1-inch diameter gear, 64 pitch = 64 teeth etc.)

0.6 module - a metric measurement of tooth pitch - I'm not 100% how it's calculated, but smaller number is a finer pitch. 0.4 module meshes with 64 pitch (although they are not identical), 0.6 module does NOT mesh with 48 pitch (my understanding is that 0.6 mod is around 42 pitch). 0.8 pitch is the coarse metric pitch - it may mesh with 32dp, I'm not 100% sure on that.

It's a bit misleading when people call 0.6 mod "metric 48" - they're not the same.

Your Twin Detonator uses 0.6 mod gears (as well as most of the current Tamiya range - they are called "AV" pinions). Some race-oriented Tamiyas use 0.4 mod. Some older offroaders use 0.8mod/32dp.

[mud4fun 1696]

Hi Jozza, if you need some 32 pitch pinions don't bother with ebay as they are pretty scarce. I got loads of brand new ones from my LHS. They are made by Robinson Racing Products in the states. £3.10 each for a steel one. You can get them in various performance coatings as well as hardened. I just got a 2 complete sets for my thundershots, the full set of 13-17t pinions []

[Virus 0]

my brain just melted with all that [:I]

different size teeth, pitch, looks like racing gonna bit a bit harder than i thought for me [V]

Paul

[mud4fun 1696]

Don't worry Virus, it isn't that bad!

Nearly all Tamiya cars before 1990 used 32pitch pinions, that includes Blackfoot, grasshopper, hornet, thundershot, falcon, bear hawk, Blitzer beetle, Bush Devil, Pumpkin etc

Most cars since then (apart from re-releases and those based on the old gearboxes) use AV size which is the same as those used in TL01. The AV size was used in Manta Ray, Group C, TL01, TB01, Wild Dagger, detonator, Vanquish, Avante2001 etc. There are very few Tamiya cars that I'm aware of use anything but these two types.

The different size of pinions ie 13tooth, 24tooth etc is simple. The smallest number of teeth give better acceleration and the highest number give higher top speed - in theory.

In fact, a smaller pinion with a high revving modern motor will have higher top speed than a larger pinion with an old low revving unit.

Smaller pinions generally make nicer driving cars that accelerate quickly and brake well, the motor is also under less strain so gives longer run times and runs cooler.[]

Each car has a range of pinions that it can take, limited by the number of sets of holes in the motor mounting. The TL01 has a very small selection, the thundershot is better. The Avante2001/Vanquish are odd in that like many high performance touring cars they have an unlimited number of combinations as the motor actually slides in and out to accommodate any size (within reason) - this allows for the best possible setup for any given track condition. [8D]

[jozza 1]

Thanks for the detail sosidge, so I should be able to order a couple of 20T .6 mod pinions for the TD.

M4F, thanks for the heads-up on the 32dp ones - My LHS stocks RR products, so should be able to get hold of them for me.

Virus, I know what you mean, when I first built my Missions for racing last year, then found out I needed a pinion for them. "Easy" I thought, and hopped onto the Apex website, to be confronted with a list of all these 48dp, 0.6mod and so on, didn't have a clue what it all meant. I wish that there could be a standard size of tooth, would make life a lot easier. And then there's the difference between metric and imperial allen screws []

With time it all becomes clear though, you pick up a little bit of information here and there, and before you know it you will become the source of all knowledge at your local r/c club []

Thanks again chaps, will be off to my local r/c car shop tomorrow with a printout of this in my grubby mitts []

[Virus 0]

ah i c now. have been looking at the tt01 manual an comparing too Tlo1 more choice with tto1 55/58/61 spur 19-22 pinion i like this one better am running my 14x3 on the 61 with a 22 pinion an man its fast so in theory if i put a 55 spur and say a 22/23 if it fits it shoould go even faster [] i hope an still have decent control too.

Paul

[mud4fun 1696]

Yes, I forgot to mention, some cars including the TB01 and its descendants use a combination of pinion and spur. While it is easy to get off the shelf pinions from anywhere in most cases the spurs are Tamiya specific. To use a smaller pinion you HAVE to fit a bigger spur and vice versa.

Clever ploy by Tamiya as it means you have to buy their stuff! I tend to avoid such cars, in fact I sold my TB01 mainly because of that reason. It was a pain to try out different motors in and also it was limited on the size of pack you could install. Pinions and spurs wear quickly when the car is used to race with. After bearings they are probably the next fastest wearing component. It gets expensive when you have to buy genuine Tamiya spurs, especially when you need a range of sizes.

I prefer a car that allows gearing changes by only pinion - much cheaper and much quicker to actually change the gearing too. From memory, to change the spur on the TB01 you must remove the rear gearbox from the chassis plate to allow you to slide the spur off the main propshaft? what a pain! On most cars I have it is simply a case of dropping on a new pinion and adjusting the mounting position of the motor - 2 mins.