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Discussion Starter #1
i have a mz3s and its around 500km!!!
when ever i want to accelerate a little faster in first & sec gear i heard a loud click click noise i think its from the front suspension (not sure )
PS i think the noise happened when the tire was skidding!!!!

is this normal ?
or anyone has this problem 2?
can anyone help? thanx!!!!
 

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Wheel hop...

I have that problem, now that there is snow on the floor.. if i take a corner hard (and I mean hard) and accelerate, ill hear a *thump thump* noise.

Then I tested my car in a parking lot with a friend looking.. and sure enough the wheel is bouncing.

Boing Boing.... just wait till i get suspension. Bounce!... be gone
 

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vaBooM said:
I have that problem, now that there is snow on the floor.. if i take a corner hard (and I mean hard) and accelerate, ill hear a *thump thump* noise.
So far I'm lucky, I only get this in first when the ground/tires are wet. haven't tried a hard bank yet faster than 45, so I wouldn't know. I hope not, I would lose all faith in the pretty 17 inch wheels.... I gave up my 15 inch chromes on the Protege 5 for this car!!
 

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MAD wheel hop is due to the small tire wall. And the weather affects this too.

Its possible you have too much air in the tires. I havent checked mine, but it feels like the fronts are a little on the hefty side. Maybe the dealer feels they need more so they dont jack the wheels up faster.

Ideal pressures, IMO, is 34-36 up front. On the rear, I usually run 40. But may go for 36-38.
 

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What exactly is wheel hop? Do the tires leave the road or do they stall for a split second in gear? Also, the manual says that ideal pressures is 32psi for the rear and the front tires doesn't it or are you using a different scale?
 

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I have extensive experience with wheelhop, interestingly not from racing real cars, but with hobby grade remote control cars. There is one Tamiya model that is front wheel drive and wheel hop is a problem when putting a big motor in that chassis.

From what I can gather, wheel hop happens in the following sequence:

When you accelerate hard on a car, the tire compresses a bit due to the traction it is generating. I am not talking about weight transfer right now, that's different. As an expample of traction-compression, look at a picture of those dragsters with the huge rear wheels, when they take-off, the side walls have clearly visible wrinkles on them as a result of the compression.

So as you accelerate, the tires compress a bit. Since a good take-off calls for a bit of tire spin, the tire breaks traction. As traction is broken, the tire decompresses. The decompressing of the tire makes the wheel bounce up. When the wheel comes back down, the tire catches some traction, compresses, loose traction, decompresses, bounces, and the cycle repeats.

On a front wheel drive car, this is exacerbated by the fact that the two wheels are independently suspended and there is a weight transfer to the rear of the vehicle. So wheel hop is very difficult to control. Wheel hop lessens when you go to a lower tire pressure because the the tire produces less bounce, just as a soft basketball bounces less than a fully pumped-up one.

On a rear wheel drive car, the weight transfer to the rear of the car compresses the rear springs and tires. This controls wheel hop somewhat, but the best are those solid rear axle cars, which control wheel hop the best.
 

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LSD equipped cars dont suffer as much wheel hop either due to the tranny spinning both wheels.

Lowering air pressure will help, but not eliminate.
 

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LeeLee said:
I have extensive experience with wheelhop, interestingly not from racing real cars, but with hobby grade remote control cars. There is one Tamiya model that is front wheel drive and wheel hop is a problem when putting a big motor in that chassis.

From what I can gather, wheel hop happens in the following sequence:

When you accelerate hard on a car, the tire compresses a bit due to the traction it is generating. I am not talking about weight transfer right now, that's different. As an expample of traction-compression, look at a picture of those dragsters with the huge rear wheels, when they take-off, the side walls have clearly visible wrinkles on them as a result of the compression.

So as you accelerate, the tires compress a bit. Since a good take-off calls for a bit of tire spin, the tire breaks traction. As traction is broken, the tire decompresses. The decompressing of the tire makes the wheel bounce up. When the wheel comes back down, the tire catches some traction, compresses, loose traction, decompresses, bounces, and the cycle repeats.

On a front wheel drive car, this is exacerbated by the fact that the two wheels are independently suspended and there is a weight transfer to the rear of the vehicle. So wheel hop is very difficult to control. Wheel hop lessens when you go to a lower tire pressure because the the tire produces less bounce, just as a soft basketball bounces less than a fully pumped-up one.

On a rear wheel drive car, the weight transfer to the rear of the car compresses the rear springs and tires. This controls wheel hop somewhat, but the best are those solid rear axle cars, which control wheel hop the best.
Here's another expaination:

The suspension and engine are connected to the rest of the car with flexible, rubber bushings and mounts. This flex kills vibrations, but it also produces a secondary, unwanted, oscillatory mechanical system. Normally, this system isn't acted on in such a way that it oscillates. When launching, with front wheel drive cars, the weight transfers to the rear of the car, reducing traction in the front. As the front tires break traction, the forces on the suspension and engine also change, setting them into motion. When the tires grab again, the forces change back the other way, now applied to a system already in motion. Now we have an oscillating force applied to an oscillating system, much like a hitting a paddleball. If you apply force to the paddle to match the natural frequency of the ball attached to the elastic string, you can keep that system going all day. With wheel hop, the motion of the system feeds back to the wheels, causing the oscillating force to sync up with it. This will also go on all day (until you reduce throttle or the transmission falls apart). The solution is to reduce the flex in the rubber band-like motor mounts and suspension bushings.
 

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Ouch

I had some really narsty wheel hop when accelerating in 2nd off of a parking lot. My car bounced with the suspension. Ouch. I'll never do that in cold/rain again!
 

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Discussion Starter #11
have any of u guys try launch ur mz3 at around 4000rpm(1st gear)
at dry surface, nice sunny weather? if yes, do u guys heard any thump thump noise ?( is that wheel hop ma?)
is there any way 2 eliminate wheel hop?

change a set of tire -anything better than goodyear RS --would it help?

thanx!!!!
 

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Albi_33 said:
change a set of tire -anything better than goodyear RS --would it help? thanx!!!!
Anything better then the RS-A will help...comes spring, when I remove my winter tires, the RS-A are going bye bye and I'll change them for another tire. Probably Yoko's AVS ES100. I'd go with the T1-S but they wear out to quickly for my walllet.
 

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Albi_33 said:
have any of u guys try launch ur mz3 at around 4000rpm(1st gear)
at dry surface, nice sunny weather? if yes, do u guys heard any thump thump noise ?( is that wheel hop ma?)
is there any way 2 eliminate wheel hop?

change a set of tire -anything better than goodyear RS --would it help?

thanx!!!!
Yep, thats wheel hop alright. Few ways to aid in high rpm launching (drag racing) is solid motor mounts, softer tire material, stiffer suspension, polyurethane suspension inserts and lower tire pressure. You'll notice at the drag strip, lots of street legal cars dropping their tire pressures to about 18-20psi. Wheel hop is in direct relation with traction. More traction, less hop.
 

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I got some wheel hop on my first test drive... something FWD cars just live with
 
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