1/12 hyper-drive pan car?

[Mr. ED]

I know hyper-drive made pan-cars and that some of those used their belt- drive pinions and pulleys: with the moter pinion pointing over to the left wheel rather the usual=right wheel. I do believe however I only ever saw them do this on 1/10th models in their own range, is that right?
This flipped over motor being a big thing for 2WD mid motored buggies (getting the momentum of the motor onto the rear wheels while accelerating) I wondered how and if this worked out for the mid-motored pan cars too? And do I remember the ads well; I think they advertised this effect already and promoted the use of this for oval racing?

I'm thinking of giving it a try on a 1/12th project but would like to hear if anyone got some input on the subject

[Phin]

Hyperdrive did make some 1/12 pan cars and since their rear pods were flat you could switch the sides tjat the motor plate went on. With a Tecnacraft rear pod you could also swap the rear pod plates on an RC12L and use the Hyperdrive belt.

You can probably flip the rear bulkheads on a lot of modern 1/12 cars as well if you make some new upper and lower pod plates.

[Phin]

Also, if you're panning on running it, what motor/battery are you planning on using?

Gearing might be a problem if you're looking to race it at 17.5T brushless with a 1C.

[shodog]

Did Tecnacraft make a 1/12 scale pod? On my 10l I used a tecnacraft pod and hyperdrive belt set up. I switched sides so I could use a mod motor

[Mr. ED]

Thanks guys,
Just to make sure I got it all right:

I know hyper-drive made pan-cars and that some of those used their belt- drive pinions and pulleys: with the moter pinion pointing over to the left wheel rather the usual=right wheel. I do believe however I only ever saw them do this on 1/10th models in their own range, is that right?

correct: they did 1/12th cars and you could use the belt drive but they were not include in those car kits as a standard

This flipped over motor being a big thing for 2WD mid motored buggies (getting the momentum of the motor onto the rear wheels while accelerating) I wondered how and if this worked out for the mid-motored pan cars too? And do I remember the ads well; I think they advertised this effect already and promoted the use of this for oval racing?

I'm thinking of giving it a try on a 1/12th project but would like to hear if anyone got some input on the subject

You guys haven't tried running this kind of set-up or heard about results from anyone who has.
Do you think it might work well?

I have some parts coming in and will see which are most suited for this (if any at all). Motorwise; probably something cheap like the old stock mabushi.
I'm running 7.2volt so gearing shouldn't be an issue... unless all my spur-pulleys and belts are too big (which could be true)

[Phin]

Did Tecnacraft make a 1/12 scale pod? ...

Sure did. If you do a search, drbellville posted an RC12L with one awhile back. I got one I'm adapting to my Agitator XII.

Thanks guys,
Just to make sure I got it all right:

correct: they did 1/12th cars and you could use the belt drive but they were not include in those car kits as a standard

I don't believe the Hyperdrive belt came standard with any of their pan cars.

This flipped over motor being a big thing for 2WD mid motored buggies (getting the momentum of the motor onto the rear wheels while accelerating) I wondered how and if this worked out for the mid-motored pan cars too? And do I remember the ads well; I think they advertised this effect already and promoted the use of this for oval racing?

I'm thinking of giving it a try on a 1/12th project but would like to hear if anyone got some input on the subject
You guys haven't tried running this kind of set-up or heard about results from anyone who has.
Do you think it might work well?

I have some parts coming in and will see which are most suited for this (if any at all). Motorwise; probably something cheap like the old stock mabushi.
I'm running 7.2volt so gearing shouldn't be an issue... unless all my spur-pulleys and belts are too big (which could be true)

The belt drive was promoted mostly for oval (which was always HD's primary market) but I believe it's primary benefit was that it shifted the weight of the motor to the inside of the car in left turns like an offset battery does.

TBH I've never run pan cars so I can't offer real world results but going off theory alone I don't think the rotational momentum will work the same on a pan car as it does in mid-motor buggies. A buggy chassis is rigid so the momentum of the motor and wheels rotating towards the front of the car plants and pushes the car forward. A pan car chassis on the other hand buckles in the middle and the rotational forces of the motor and wheels both spinning towards the front of the car would tend to push down at the t-bar/links and pull the rear axle up. That makes me think that the rear end would be loose unless you use a stiffer center shock spring.


Again though that's just imagining how the forces would act in my head...I may very easily be missing something and it actually works quite well in the real world.



If you're not going brushless/lipo you should be okay on gearing. With a 17.5T/1C set up the largest HD pinion and smallest HD spur aren't going to give you a good enough ratio. If someone wanted to do a belt drive with brushless I think they'd have to look more at adapting the diff pulleys from a TC.

[Mr. ED]

TBH I've never run pan cars so I can't offer real world results but going off theory alone I don't think the rotational momentum will work the same on a pan car as it does in mid-motor buggies. A buggy chassis is rigid so the momentum of the motor and wheels rotating towards the front of the car plants and pushes the car forward. A pan car chassis on the other hand buckles in the middle and the rotational forces of the motor and wheels both spinning towards the front of the car would tend to push down at the t-bar/links and pull the rear axle up. That makes me think that the rear end would be loose unless you use a stiffer center shock spring.


Again though that's just imagining how the forces would act in my head...I may very easily be missing something and it actually works quite well in the real world.



If you're not going brushless/lipo you should be okay on gearing. With a 17.5T/1C set up the largest HD pinion and smallest HD spur aren't going to give you a good enough ratio. If someone wanted to do a belt drive with brushless I think they'd have to look more at adapting the diff pulleys from a TC.

Thanks for your input.
I've used a diff pulley before as spur with a short belt. The problem though is to find motor 'pinions' in M3 pitch.
I have one tiny one. And one which is easily double the number of teeth, but that's it and I have no clue where to find more.
The m3 pitch did prove a lot stronger than the belt pitch on my ultima hyperdrive conversion. But for 12th scale those tiny hyperdrive teeth may be good enough.

[GoMachV]

Did you try this store I posted on a different thread? They have to a of metric and std pullies, look just like our pinions
https://sdp-si.com/eStore/

[Mr. ED]

I'm confused on which pitch to look for: 3mm, but GT2 or HTD?

[GoMachV]

I don't have the answer as I don't have the belt to compare, but here is the website for Gates and it shows them

http://www.bbman.com/products/gates-timing-belt-pulleys.html

[Phin]

Most TC pulleys I believe are S3M/STD but check the shape of the teeth on your belt. If they're sharp trapezoids they're STD, if they're curved they're HTD or GT2.

For the most part you can swap pulleys/belt profiles as long as the pitch (3mm) is the same but it won't be as efficient and may cause stress to do a combo. It's less of a problem to use an HTD or GT2 profile belt in a STD pulley since the first two both have a lower tooth depth....so if you're going to order a GT2 or HTD pulley and have an STD belt you may also want to order a new belt.


Here's a couple of good info links that helped me:
http://www.racerlog.com/wiki/Touring_Car_Belts
http://www.pfeiferindustries.com/timing_beltstooth.htm
http://www.rctech.net/forum/electric-road/30530-alternative-belt-suppliers.html

[Mr. ED]

followed some links from the links in the links.. and got completely confused but I did find that practically nobody offers much choice for 3.2mm (1/8") bores

[Phin]

Not hard to make a spacer. Associated makes them for 5mm to 1/8" pinions. PN ASC91161

[Mr. ED]

I got the first parts in on friday; a car actually. After some inspection I don't think this will be the base for the belt-drive build though: it would require a very long pinion