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View Full Version : Anyone balance there mini z wheels???


dorifto46
2010.04.01, 04:36 PM
So lately ive been looking into fine tuning the mini z and came across wheel vibration in the rear of my car on throttle. Yes, I used the PN tire installer to install the tires on various rims and checked the driveshaft for any tweaks. Most of the tires and rims dont vibrate but once in a while i will come across one that does.

Im looking into purchasing a Du Bro airplane prop balancer to balance the wheels.. Anyone have any experience with this balancer or anything else similar? I tried putting bearings in the wheel and balancing it by spinning it on a tool but i want to see if i can even get a more accurate balance.

Eman
2010.04.01, 07:45 PM
I've thought of doing this myself but, it would be tedious to say the least. You could balance the 2wd cars easy enough by doing just what your doing now. Not sure how to go about balancing 4wd wheels and tires. With the lug loose spin the wheel, when it stops mark the bottom the part of the wheel that is pointed down. Spin it again, if the marked part of the wheel is at the bottom again then you know that is the heaviest part of the wheel/tire. Then add weight to the opposite side (top) of the wheel. You want to keep doing this until no one part of the wheel constantly stops at the bottom. Basically thats how you could do it. Don't know how much weight to start with though. Might be more hassle than its worth.

EMU
2010.04.01, 09:30 PM
I dont know if I would add weight, but manipulate the weight (tire) that is already on the wheel.

cosmicsoul
2010.04.01, 10:29 PM
If you were going to try it, sand some weight off rather than adding. Thats how guys balancing propellers do it.

pedrocamp
2010.04.01, 11:22 PM
I have a magnetic prop balancer I used to balance my 10th scale TC wheels and tires and tried to check my Z wheels. The Z wheels and tires just don't have the mass and leverage to get a balance reading with my current balancer. If the shaft were carbon with steel tips perhaps the wheels would be able to spin the shaft. The shaft has to be extremely straight and the tip points must have extremely small runout.

dorifto46
2010.04.02, 11:30 AM
I was talking to a fellow racer yesterday. he told me in order to use the prop balancer with the miniz wheel, I would have to put a perfectly balanced proo next to the wheel while balancing. The wheel is to light for it to work properly on it's own.

JuniorWKR
2010.04.02, 11:45 AM
would you be better off trueing the tire as the rim may be oblong and not necessarily outta balance?

pedrocamp
2010.04.02, 12:18 PM
I would balance the mounted tire and wheel together. I would think the prop would add more mass that the wheel/tire would have to work against. I beleive you would want the shaft as light as possible to allow the weight offset to show itself, the imbalance (offset) becomes a higher percentage of the total wheel/tire/shaft weight.

chad508
2010.04.02, 03:04 PM
wont the tire balance itself after scrub in. i thought thats why treaded tires will have slick spots in some areas

color01
2010.04.02, 05:04 PM
That's part of the equation, but if you balance them before that happens you can get a little more treadlife and more consistent grip out of the tire (flat spots on a tread won't increase your maximum grip, clearly).

If your Mini-Z is 2WD, and you use CNC-machined wheels (PN or PN multi-offset or Mantis multi-offset or any quality alu. rims) then you can just install tires using the PN tool and forget about balancing. The tire is typically cast well enough that as long as you're careful about setting up the PN tire tool, the tire mounting job will be nearly perfectly balanced anyways (checked using wheel/tire combo on an axle with Reflex bearings -- you could do a further check with ABEC-7 ceramic bearings, I suppose, but it's pretty overkill...).

For AWD I don't know if balancing will help, because the axles themselves cannot be balanced perfectly (the dogbone axle is just free to swing around inside the diff outdrive!). You can check the wheel balance if you have good bearings, just take out an individual knuckle and disassemble the CVD. I think the AWD only has alu. rims for machined rim options though, there's not a bit enough market for Delrin racing rims... so you probably could detect a noticeable imbalance on plastic rims using this method.

EMU
2010.04.02, 06:34 PM
PN has the bolt on wheel adapters for AWD as well as 2wd... So, you could balance them with the bearing adapter, then switch for the AWD adapter after they are balanced. I wouldnt think that the adapter would upset the balance enough to be significant.

benmlee
2010.04.17, 02:21 AM
This is most likely the rim is bent rather than a balance problem. Even if you get the wheel to balance perfectly, when you mount it on the diff, the freeplay and tolerance there would most likely throw off the balance already. Might have better luck with the front wheel. If you really want to balance the rear wheel, it would be best to mount them on the diff, then balance the entire assembly on something like a Du-Bro True-Spin balancer. Then again, that machine is probably not sensitive enough to balance mini-z wheels as mentioned.