iblumberg

I just got an HPI Pro 4 Hara and it included both a spool and a one way (no front ball diff though). On my previous cars, I only used a front ball diff. I usually race on asphalt with low to medium traction (though I may race a few times on carpet over the winter).

Sorry for asking something that has likely been discussed previously. Can someone post a brief summary of when or why to use the spool versus the one way? Also, are there any circumstances where a ball diff would be the best choice?

Thanks,
Ira

Superkarter

iTrader: (2)

You will need different setups for both.

The one-way generates a lot of steering and corner speed but you have no front brakes. Use the one-way on tracks that don't require a lot of hard braking.

The spool reduces steering at the front end with the same setup as the front wheels can't turn independently of each other but a spool carries lots of corner speed and is far superior to a ball diff in braking. The spool is probably more useful on tight tracks with lots of braking.