Oversized Tires on a B4.1: Pros and Cons?

[rapscallion]

Hello.

I recently picked up a B4.1 brushless RTR. Everything is stock and I'm enjoying it alot, but the nearby track is really laid out more for larger vehicles. There are many rough rutted sections, and some of the gaps that need to be jumped are way outside of my car's range in stock form.

I'm already planning to experiment with gearing to get more speed for clearing the massive gaps, but I was also considering some larger tires.

I was looking at some DIRT HAWG buggy tires, which seemed to be slightly taller/wider than the stock pins/ribs that come with the car. But was also considering the possibility of using T4 wheels/tires.

Ideally, I'd like to keep the gearing as close to stock as possible and rely strictly on pinion changes where necessary.

Does anyone have some tips/photos for upsizing your tires to gain more stability and top end speed on oversized tracks?

Thanks!

[Charlie don't surf]

Jconcepts J-82 kit's converted the truck to an 1/9th scale "buggy" that tire and rim package may suit your 1/8 scale track needs

[rapscallion]

Thanks for that tip. I'm going to contact them to get more specific specs on the wheels/tires that they offer.

It looks like the wheels/tires are just normal B4 sized items, but I'll post back here with dimensions if/when they send the info to me.

[kaiser]

the j82 is really cool on bigger tracks. i was running one last summer at a large 1/8 track.
i eventually ended up just using the long chassis and put all the b4 parts back on, and it was still nasty on that long track.

[Zipster]

Does anyone know if the J82 kit would fit/work on a T2? I have one, but am really not much of a truck guy - thinking it would make a good "fun buggy"

[kaiser]

nope, it's a conversion kit for the t4.

[rapscallion]

I sent an email to JConcepts to get more information; they said their rims/tires are definitely larger than the stock rims/tires, and they sent me two images to illustrate:





You can see a raw B4, then a T4 with the J82 kit, then a true 1/8 scale buggy.

I asked them in a follow up email if the J82 wheels/tires could be used with a B4, and they said no. I'm slightly surprised by that response, because I can't think of any reason why it wouldn't work other than possible rubbing issues. Can anyone offer some possible ideas for why these rims/wheels would not mount on a B4?

[kaiser]

j82 wheels are just 2.2 truck wheels, with the narrow (old rc10t style) front wheels.
you may need t4 front axles if they are wider.
i don't see whay they won't fit. i'll bolt a set of rear truck tires on my b4 tonite and let you know.

[rapscallion]

j82 wheels are just 2.2 truck wheels, with the narrow (old rc10t style) front wheels.
you may need t4 front axles if they are wider.
i don't see whay they won't fit. i'll bolt a set of rear truck tires on my b4 tonite and let you know.

Cool! Thanks! Definitely appreciate you taking the time

[soniccj5]

I wonder if you could bolt on a SC10 chassis to get closer to the 1/8 buggy length. Might have a problem mounting the body though.

[rapscallion]

so...after digging a little deeper, I discovered that there are adapter kits on the market that are intended for allowing standard 17mm hex mount 1/8 scale buggy and truggy wheels to attach to Associated SC10 axles front and back; the same kits have been tested and supposedly work with T4 and B4 as, as well...

this seems like a much better option that buying a specialty rim/tire set from Jconcept everytime I need some new rubber; I much prefer going down to the local hobby shop and getting whatever strikes me on the spot.

I ordered a version of the adapter from DYNAMITE (part #Dyn8070) for $23 with shipping included on ebay. There are several other manufacturers of similar items with prices ranging up to $50 for a complete set. Here's a photo of the ones that I got:



the two smaller adapters go on the front, using your stock bearings, axles and mounting nuts; the two larger adapters go on the back and again use your stock equipment to lock the adapter in place on the stock axle. From that point forward, you can use any standard 1/8 wheel for the front and back.

I'd assume that my gearing and slipper clutch might need some adjusting to cope with the oversized tires, but nothing too complicated.

As soon as I get these, I'll mount them up and take some pics

[rapscallion]

FYI: I received the adaptors last week in the mail and they look like they are going to work very well; my 1/8 buggy wheels and tires should show up this week....

Sometime this coming weekend, I will be out at the track testing this 'big tire' set-up along with a new 10t motor. Should be interesting to say the least

[Coelacanth]

I'm surprised nobody has mentioned this, but going to bigger diameter tires (all else being equal) will decrease your torque & acceleration and increase your top speed. If you keep your gearing as it is now and add larger tires, it'll take more work to get them moving. You might want to downsize your pinion gear a few teeth to keep things equal and performing the way you're used to.

[rapscallion]

I'm surprised nobody has mentioned this, but going to bigger diameter tires (all else being equal) will decrease your torque & acceleration and increase your top speed. If you keep your gearing as it is now and add larger tires, it'll take more work to get them moving. You might want to downsize your pinion gear a few teeth to keep things equal and performing the way you're used to.

Thanks for the feedback! That is more or less what I was expecting, but I wasn't sure exactly how much things would change. Up until recently, I've been running the stock 3300kv Reedy Motor that came with the car - but I'm upgrading to a 10.5T sensored motor at the same time as changing to these bigger wheels/tires, so I'm not really sure what to expect. The new motor/esc combo says 3270KV on the package, but I've read that sensored and sensorless motors are so different in performance characteristics that direct comparison between KV ratings does not work.

I'm planning to order a pinion set with 6 gearing possibilities so that I can dial things in for every situation.

[Jeep-Power]

I am digging those larger front buggy tires/rims.

Is there a part # for them?

Are they ordered directly from JConcepts?

What is their overall height/diameter, please?