Torque twist and motor position?

[MOTORRAD]

Ok guys (I know alot of you run E-maxx trannys so I put this in general crawlers section) Has anyone out there experimented with which motor position on an emaxx tranny (left or right) produces less torque twist (if it even does). Im going out on a limb here since I am experiencing horrendous torque twist right now. Let me know if Im just dreaming that this will make a difference or not.
Dave.

 

[sambmx]

The only difference would be the slight weight difference by moving it to the right, it wont effect torque steer much if at all.Its all in link and shock geometry you just need to experiment.Ive reached a point where there is no noticable torque steer at all on my shafty.

 

[vinny]

You might be able to help the twisting by changing the position of your link mounts on the axle and chassis. On 1.1 scale crawlers we can change how the vehicle squats, rises, and twists under acceleration by ghanging link length, and mounting position. A little bit can make a big difference.
Hope this helps! :!:[/img]

 

[MOJOJOJO]

my theory is that if you can have one of that shafts that exits the trans to reverse direction before it goes to the diff that it would eliminate the tourque problem.. basicly put a gear box with a 1:1 ratio that the output would spin the opposite direction...

Ian

 

[toyofast]

How are your shocks setup? Like oil weight & spring stiffness??

What motor and gearing are you running?

Battery placement? If you have it on the chassis, try straping it to the front axle for a test run...... 8)


Our Maxx trucks don't seem to have any torque twist or none that is noticable when crawling.

 

[MUD4FUN]

I also suffered horrendous torque twist on my homebuilt shafty crawler when I first built it but I've made some changes which have now virtually eliminated the twist.

1) Increased wheelbase from the original 11" to 13", this does two things, it reduces the propshaft angles to acceptable ones and the longer wheelbase helps balance the vehicle when climbing/decending steep inclines.

2) Fitted a reduction gearbox to give me 65:1 gearing which means I can idle at virtually no revs and still pull the vehicle over obstacles. The lack of revs also reduces the twist problem.

3) Changed my shock locations so that the shocks are angled back from the axle to the chassis slightly (they were vertical before) and also moved the lower shock location outboard on the axle just enough so that they are slightly angled in at the top. They were originally vertical here too.

4) I changed my 'A' frame location on the top of the axle to be just in front of the axle center line, previously my 'A' arms location was almost vertically above my lower link axle locations behind the axle center line.

I also fitted shock spacers on just the two opposing corners that suffered the worst twist (the axle would almost rise to the chassis under even a small amount of power!) I left the soft springs and oil in though as it allows better articulation.

The increase in wheelbase also gave me an increase in cross axle articulation to 9" from 7" as well as solving the twist issue. Only downside is loss of ramp breakover angle but I still have 4" of clearance so not too bad.

Hope this helps, Ian.

Here are the latest pics of my crawler: