Use of BB's in tires

[RockyD]

Are BB's in the tires working for those who have tried it?

Loose BB's doesn't seem to make sense as the extra weight will shift to the lowest point in the tires thus making level ground the only place where they help traction.

If you add weight in any form that doesn't shift, and is evenly distributed around the center portion of the rim inside the tire should give you the same effect. i.e. putting more unsprung weight onto the tire contact patch. This could be in the form of a soft lead weight fastened around the center of the rim or even heavier wheel material.

Most everything I see advertised for R/C cars/trucks is based on racing requirements and except for suspension and strength issues doesn't apply to crawling.

Just some thoughts on this issue from a newbie trying to figure out what might work and what doesn't. I haven't finished my TXT-1 buildup as I seem to keep finding something else that appears to needs upgrading. I need to stop reading this forum and get my rig running so I can try out some of my theories.

[SR5Dave]

Like you said, BBs stick to the lowest point in the tire, so you get all that weight (around 4-5 pounds) right at the ground. Even when you're going uphill, they're still lower than everything else, so it does help, although possibly not AS much (but still a LOT!). If you had steel rims or something lets say.. The rim is going to be higher than the lowest point on the tires, unless you're upside down, in which case it won't matter

Now here is the other fantastic thing about BBs and water and such...

When you add steel rims or a ton of lead to the rims.. You're increasing the rotating mass of everything a LOT, this means your motors will have to work way harder to rotate a 2 pound rim, as it would a light plastic or aluminum one. The bb's or water (water for the 1:1 comp guys) roll in the bottom and don't add to your rotating mass, therefore don't steal any power. Its a beautiful thing ;)

[RockyD]

SR5Dave:
Thanks for getting me straight on the BB's issue. I hadn't thought of it in that way.

Right now I was intending to use IMEX BAJA tires as I like the tread pattern. The are mounted on narrowed stock TXT-1 rims. Because the rubber is so soft I have installed soft foam as the tires were distorted from being stored improperly and didn't support the weight of the rig enough in my view. I still think the foam is necessary but now it means I can't use BB's. May have mount stock tires to use BB's. I am anxiously awaiting the new IMEX tires they keep promising and the Composite Maximizer Beadlocks forthcoming this summer.

Anybody had experience with the IMEX BAJA's for crawling?

[SR5Dave]

Originally Posted by RockyD

SR5Dave:
Thanks for getting me straight on the BB's issue. I hadn't thought of it in that way.

Right now I was intending to use IMEX BAJA tires as I like the tread pattern. The are mounted on narrowed stock TXT-1 rims. Because the rubber is so soft I have installed soft foam as the tires were distorted from being stored improperly and didn't support the weight of the rig enough in my view. I still think the foam is necessary but now it means I can't use BB's. May have mount stock tires to use BB's. I am anxiously awaiting the new IMEX tires they keep promising and the Composite Maximizer Beadlocks forthcoming this summer.

Anybody had experience with the IMEX BAJA's for crawling?

Someone posted about using Foams and BB's... Apparently you can do it? Search here to find the thread ;)

Dave

[DirkDigler]

I use foams and BBs. Just cut the foams thickness down and use the inner ring you cut off. It will sit closer to the wheel and not the outside portion of the tire. The BB's roll under the foams.

[RockyD]

Thanks Dirk, I'll give it a try.