6 Speed

[McFig]

Check this out. Would this even work?

http://www.tamiya3speed.com/forum/attachment.php?attachmentid=129

[william]

yes, but the vehicle would be very large to hold it all. That has to be 11'' or more from motor end to the trans output

[outtaOakland]

Wouldn't that be a 9 speed?

3X3 = 9 ???\


Neat idea anyhow!

[Larrio]

Could the stock motor and ESC even handle that? I think it could work, although you would be counter-acting the effects of gearing unless you changed the ratios. Because if you shift into 3rd on tranny 1, putting it into 3rd in tranny 2 would net the same final drive and putting into 1st in tranny 2 would reduce the taller gear ratio in tranny 1 (3rd setting)

I think its still considered a 6 speed. 3 different gears in 2 gear boxes (3x2 = 6)

[william]

it would be 9

second trans if in first, then the 3 gears from first trans
second in second then 3 gears freom first
second in third then 3 gears from first

put both in first it would be a real slow crawl

if third is 1:1 on each that gear would basicly cancel the second trans out mathmaticly. The only difference being the spur-pinion ratio between the 2 gearboxes.

[Larrio]

outtaOakland: you were right, it is a 9 speed.

Nice explanation William.

[protrker]

No, it's a 6 spd.

1st & 3rd vs 3rd & 1st cancel each other out.

Just as 1st & 2nd vs 2nd & 1st does as well.

The size of the pinion off the 1st trans into the 2nd trans has no effect in relation to the ratios of the 2nd trans.

The ratios would be:
1 & 1, 1 & 2, 1 & 3, 2 & 2, 2 & 3, 3 & 3

It's a novel idea, but there are simplier gear reductions available now and much more compact too.

For me in my Tam trks, I'm using a Wedico twin motor coupler to run dual 12v motors (full load speed 4000rpm) and within that coupler, instead of the idlers between the motor pinions and the center main drive gear/shaft, I have one large gear on the center output shaft running off both motor pinions to give me a 3:1 reduction.

And with the HiLift t-case bolted to the back of the semi trans, that gives me another 2.1:1 reduction.
1st gear, overall reduction is 204.687
2nd gear is 111.258
3rd gear is 67.158

With my 6wd trks, loaded or empty, no matter the grade, I run around the basement in 2nd all the time. Lots of pulling power and long run times on 2200mAh 12v Batts.

http://img.photobucket.com/albums/v150/protrker/IMG_0455.jpg

http://img.photobucket.com/albums/v150/protrker/IMG_0457.jpg

[McFig]

^^^^^^^
What he said, its 6 speed. I was thinking about it last night and at frist I thought it was 9, but then realized the cancel part, sooooooo 6

Nice mod ^^^

[Larrio]

DOH! I was right, wrong, and then right again.

Oh that mod is cool!

[william]

gears are only cancelled out mathmatically, mechanically they're all there. :LOL:

[outtaOakland]

The size of the pinion off the 1st trans into the 2nd trans has no effect in relation to the ratios of the 2nd trans

Ha, good observation Protrker!

I was thinking of my old ten-speed bike I had as a kid - two in the front and five in the back.

Forgot that 2nd gear basically works like a lay shaft!

-S

[oztruck]

It has 9 gears but only 6 speeds:Tamiya1:

[Larrio]

that seems like a waste. =D

[calm n sedated]

WASTE! more gears, more fun, more realistic! Just like a true semi, go through 6 plus gears just to hit 30 mph.

[trailqeen]

thats cool

[chafey]

WASTE! more gears, more fun, more realistic! Just like a true semi, go through 6 plus gears just to hit 30 mph. only with a hi revving brushless:dance: