rims, tires, mounting balancing questions

[nuQ]

i'll be getting the rims that i bought off ebay this week(the chrome 99Q rims) i'll also be ordering new tires off tirerack or tires.com, narrowed down to the kumho 712's(if i stay cheap), or the firestone sz-50's.

i'll be getting all this done at the local ford dealership since they have the only hunter 9700 around and 12$ a tire for the install.

i won't have the luxury of watching the install in person, so i want to make sure to request/demand the correct procedure to be carried out. my questions are;1. should the rims be balanced seperatly before the tires?2. should anything special be done to correctly balance the tires?3. an alignment is a given, right?

anything i missed? like i said, i want to make sure that the mounting/balancing procedure is done the right way. thanks guys!!! jeff

[SmithSR]

1. not necessary, but since you're buying used wheels, please insist that the tech pay extra attention for bent/out-of-round wheels.

2. the Hunter will do the job if a good tech is operating it. Insist upon a *dynamic* balance, which will place wheel weights on both edges of the rim. The Hunter has an option which allows for a dynamic balance, while keeping all the wheel weights on the backside of the rim(tucked in behind the spokes, for instance) so you don't have to see them and you still get an optimized balance job.

3. When was your last alignment? Look at it this way, an alignment check is never a bad thing. And it's a good habit to get into for preventative maintenance reasons. Also, how are you old tires wearing? Evenly? I think that would be my deciding factor.

[Highway Q45]

FWIW I had some problems on a recent purchase with the Kumho 712's in 245/50/16 (97) when balanced on a Hunter 9700. 3 of 4 tires would not meet spec.; the rims were fine. Supplier replaced all three tires and wheels but said he had to mount quite a few to get 3 to pass on his 9700. The Hunter will give you runout measurements on the rims(lateral and circumferential), pass/fail (tire/wheel), and locate the sweetest spot for final tire location based on the tire balance. The "road force" balance on the same machine will establish the final weight placement. After all is said and done I now have 4 well balanced tires with less than 1.5 oz each. The Q now rides very smooth with 35 psi; turn-in and lateral grip is so much better than the Michelins. Road noise has increased a bit but it's not annoying. I hear the Firestones are pretty good also but have never used them. Things to look for at balancing time:

1. Agree before hand when you get the tires that the tires will take no more than 2-3 oz. or the supplier will pay for the rebalance, shipping, etc.2. Watch the process and make sure you get a printout (it seems the Hunter printers never work?);3. Test drive them at all speeds, if you are going from the OEM 15's the plus sizing will make any weak spots in other suspension components seem more noticeable.

Steve

[Jeff Williams]

A close friend has th Kumho tires on his '91 300 ZX Turbo. He dosen't like them. They are noisy. So are my Nitto NT-450's

It sounds like you have a handle on the tire balancing.

Make SURE they are using torque sticks on their air wrenches, or INSIST on hand-tightenin, and torquing (sp?) of the lug nuts. If not, this can create a vibration, and brake wear problem.

[Q45tech]

"and done I now have 4 well balanced tires with less than 1.5 oz each. The Q now rides very smooth with 35 psi.

1.5 ounces is gross, that's 42 grams. Way out of spec."3 of 4 tires would not meet spec"

What spec were you using ....the 15-20 lb spec is grossly inadequate for a lux car with soft springs - tires need to be under 5 pounds radial force at 70 mph!!!!!!!!!!!!The wheels should require no more than 5-7 grams per side [worst case] to balance them standalone!Then the tires should certainly not require more than 10 grams extra per side and this should actually be smaller since there may be some cancellation.

Try a set of Michelins if you want a round tire that might stay round for 10,000 miles

[Highway Q45]

Nothing personal but I removed my OEM Michelin XGT H4 Pilots after two spinouts in the rain. They only had 10K, at least 50% tread left and they were about the worst tire I've ever had on any car. The high-mileage tread compound is too hard for wet use and they just felt un-connected at speeds over 80 mph. The printout for the the Kumhos on the Hunter 9700 just said "Excessive road force variation (xxx lbs)- Does not meet OEM spec-Recommend tire replacement" The dealer I ordered them from consented to 3 tires only. I don't know if they use any Nissan criteria or just a constant for tire size. The 1.5 oz was on the one tire the machine didn't reject but they balanced it well enough to be very stable. The 3 replacement tires took 7, 7, and 14 grams respectively. Cheap tire or not, they are glass smooth, wearing well(7K), grip well wet or dry. I'm not implying that I made a great tire decision, only that they fulfill everything I was looking for at a decent price.

As far as the original post goes he'll be using a larger rim and much heavier tire...I can't imagine there's many + size tire/wheel combos out there that will consistently take 8-17 grams. Kumho 712's are heavy with a very stiff side wall, I'm sure NuQ can do better given more Q dollars at his disposal.

[nuQ]

thanks steve, wish i had more "Q" dollars at my disposal!!! i will probably be going with the kumho's. about half the cost of the firestone's(although i know from personal experiance it's a great tire), and many, many positive testimonials of the kumho's, i think that's the best option at the moment. with the money i save i plan on fuel system cleaning(tb, plenum), hoses, o2 sensors, shocks, etc. jeffps- after years of experiance driving rear wheel cars, the wet performance is a MAJOR deciding factor.