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Old 07-12-2004, 08:27 PM   #46
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Durring mid corner the weight is transfered to the outside tyre and the inside doesn't grip as well which allows the car to turn with the wheels turning at the same rate.

The inside tyre slips.

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Old 07-12-2004, 08:29 PM   #47
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Quote:
Originally posted by Rabbit
a front one way is designed to allow the inside tyre to run at a different speed to the outside tyre (one travels more than the other) so how can both be locked together.. doesnt make sense!!
I agree with this. For some reason people have got into the mentality that a one-way axle is a diff. Its not a diff. Its a solid axle with one-way bearings to allow each side of the car to operate separately from one another. It is the same principle as the older 1:8th on-road cars that had a solid axle in the center and the one-way bearings in the hubs. The only difference being the one-ways are transferred to the axle to transfer the excess weight closer to the Center line of the car to improve cornering performance.

The only time the 2 front axles are locked at the same time is in a straight line. In corners only the inside wheel at the front drives while on-power and the outside wheel rotates faster to ensure a that minimum scrub of speed occurs during the corner. When off-power both front wheels rotate freely independant of the rest of the drive train (effectively a 2WD car) which is better for faster direction change through fast flowing chicanes.
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Old 07-12-2004, 08:32 PM   #48
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Quote:
Originally posted by Rabbit
a one way diff works with 2 one way bearings, one for each wheel. under power and in a straight line there is no doubt that both wheels are locked. but if a car is mid corner and the outside wheel is spinning faster (under power or not) the one way bearing wil allow it to spin freely. correct?

hence you may say that this setup allows slip!
Crudely speaking you could call it slip I guess, but it is not really slipping. Under acceleration it is always locked (it is the drivetrain speed which locks the wheels not vice versa) and off power the wheels are completely free.
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Old 07-12-2004, 08:36 PM   #49
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Quote:
Originally posted by Palmaris Europe
I agree with this. For some reason people have got into the mentality that a one-way axle is a diff. Its not a diff. Its a solid axle with one-way bearings to allow each side of the car to operate separately from one another. It is the same principle as the older 1:8th on-road cars that had a solid axle in the center and the one-way bearings in the hubs. The only difference being the one-ways are transferred to the axle to transfer the excess weight closer to the Center line of the car to improve cornering performance.

The only time the 2 front axles are locked at the same time is in a straight line. In corners only the inside wheel at the front drives while on-power and the outside wheel rotates faster to ensure a that minimum scrub of speed occurs during the corner. When off-power both front wheels rotate freely independant of the rest of the drive train (effectively a 2WD car) which is better for faster direction change through fast flowing chicanes.
interesting.. that is correct its not a diff, so why do the manufacturers call them diffs??
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Old 07-12-2004, 08:40 PM   #50
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Quote:
Originally posted by Palmaris Europe
I agree with this. For some reason people have got into the mentality that a one-way axle is a diff. Its not a diff. Its a solid axle with one-way bearings to allow each side of the car to operate separately from one another. It is the same principle as the older 1:8th on-road cars that had a solid axle in the center and the one-way bearings in the hubs. The only difference being the one-ways are transferred to the axle to transfer the excess weight closer to the Center line of the car to improve cornering performance.

The only time the 2 front axles are locked at the same time is in a straight line. In corners only the inside wheel at the front drives while on-power and the outside wheel rotates faster to ensure a that minimum scrub of speed occurs during the corner. When off-power both front wheels rotate freely independant of the rest of the drive train (effectively a 2WD car) which is better for faster direction change through fast flowing chicanes.
I dont agree totally. You are assuming that both front wheels have 100% traction on the surface. During cornering the ouside front wheel has the most load hence grip and in general with full power of a nitro car applied the inside wheels first locks briefly then begins to slip and break traction whereby the front outside wheel grips and its speed of rotation dominates the oneway, hence the inside wheel is forced to spin at the same speed as the outside wheel. It is similar to when a 2 speed shifts and the shaft is now rotating faster the slower 1st gear disengages, not the faster 2nd gear. In high grip lower speed situations it is possible that the inside wheel will dominate and the outside will free roll. Effectively if one wheel lifts off the surface or loses grip the diff wont allow the drivetrain to unload.
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Old 07-12-2004, 08:46 PM   #51
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I agree with AMGracer! All of the oneways ive heard of "LOCKS" if any power is applied whether a little or a lot!
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Old 07-12-2004, 08:46 PM   #52
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Quote:
Originally posted by AMGRacer
I dont agree totally. You are assuming that both front wheels have 100% traction on the surface. During cornering the ouside front wheel has the most load hence grip and in general with full power of a nitro car applied the inside wheels first locks briefly then begins to slip and break traction whereby the front outside wheel grips and its speed of rotation dominates the oneway, hence the inside wheel is forced to spin at the same speed as the outside wheel. In high grip lower speed situations it is possible that the inside wheel will dominate and the outside will free roll. Effectively if one wheel lifts off the surface or loses grip the diff wont allow the drivetrain to unload.
you are correct the outside wheel will kick in if wheelspin is present.. but there has been no mention of loss or traction that is a whole new argument
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Old 07-12-2004, 08:50 PM   #53
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Quote:
Originally posted by AMGRacer
I dont agree totally. You are assuming that both front wheels have 100% traction on the surface. During cornering the ouside front wheel has the most load hence grip and in general with full power of a nitro car applied the inside wheels first locks briefly then begins to slip and break traction whereby the front outside wheel grips and its speed of rotation dominates the oneway, hence the inside wheel is forced to spin at the same speed as the outside wheel. It is similar to when a 2 speed shifts and the shaft is now rotating faster the slower 1st gear disengages, not the faster 2nd gear. In high grip lower speed situations it is possible that the inside wheel will dominate and the outside will free roll. Effectively if one wheel lifts off the surface or loses grip the diff wont allow the drivetrain to unload.
Ok. I know where you are coming from with this and agree this will happen with a low bite track. However, a one-way is more suited to faster flowing hi-bite tracks. With this style of track you want the front anti-sway bar as hard as possible to keep both wheels on the road. This negates the majority of weight transfer to the outside wheel which keeps the grip and drive to the inside wheel.
With low-bite tracks you want to have the anti-sway bars soft or off completely and preferably a diff or full solid axle in the front.
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Old 07-12-2004, 08:53 PM   #54
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Quote:
Originally posted by Johnnytc3
I agree with AMGracer! All of the oneways ive heard of "LOCKS" if any power is applied whether a little or a lot!
Yes. But in a corner they only lock to one wheel. A solid axle works great on smaller twisty tracks. If a one-way axle locked completely in the corners under power then why do they not work too good on twisty tracks with a nitro car??
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Old 07-12-2004, 08:57 PM   #55
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Quote:
Originally posted by Palmaris Europe
Ok. I know where you are coming from with this and agree this will happen with a low bite track. However, a one-way is more suited to faster flowing hi-bite tracks. With this style of track you want the front anti-sway bar as hard as possible to keep both wheels on the road. This negates the majority of weight transfer to the outside wheel which keeps the grip and drive to the inside wheel.
With low-bite tracks you want to have the anti-sway bars soft or off completely and preferably a diff or full solid axle in the front.
Yep agree. Also in high bite circumstances the inside wheel lifts often on power (at my track anyways) and the outside does the driving. Either way the speed differences are not great between the wheels and the diff is effectively locked, you certainly would not consider it "limited slip" as a oneway bearing can only be locked or free.
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Old 07-12-2004, 08:59 PM   #56
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true and if a one way lockae both wheels at any amount of power your machine would understeer into the wall all the time!

when the outside tyre slows to the same rotation as the inside one the bearing grabs it and pull the car out using both wheels..

have a look at the "yaw control"system on the evo 8 lancer they are surprisingly similar
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Old 07-12-2004, 09:00 PM   #57
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Having tried the FW-05R for half a year, i have decided to switch back to belt car.

But my experience with the shaft car was a pleasant one. the maintanance was easy as the drive train was much more straight forward. However i felt that the crown gears worn abit too fast and unpredictably with a powerful engine. Also having too powerful an engine resulted in tire spin as the power was transmitted to the wheels too directly. However this aslo meant greater response from the shaft car. Good or bad? you decide, as it means shaft car can achieve the same result as a belt car with a more powerful engine.

I just felt more comfortable with a belt car simply because 1/8th scale on road nitro cars are running on belt. And that to me just means that shaft cars have some problem handling high speed. True or not? You tell me.
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Old 07-12-2004, 09:04 PM   #58
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Quote:
Originally posted by moby
Having tried the FW-05R for half a year, i have decided to switch back to belt car.

But my experience with the shaft car was a pleasant one. the maintanance was easy as the drive train was much more straight forward. However i felt that the crown gears worn abit too fast and unpredictably with a powerful engine. Also having too powerful an engine resulted in tire spin as the power was transmitted to the wheels too directly. However this aslo meant greater response from the shaft car. Good or bad? you decide, as it means shaft car can achieve the same result as a belt car with a more powerful engine.

I just felt more comfortable with a belt car simply because 1/8th scale on road nitro cars are running on belt. And that to me just means that shaft cars have some problem handling high speed. True or not? You tell me.
did this car have a one way?? that usually eliminates too mych tyre spin..
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Old 07-12-2004, 09:07 PM   #59
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Anyway to keep on topic. Belt drive is better

Can anyone tell me the price of belts these days? Havent bought a spare belt for a 200mm car yet. Both my Yokomo's and my Serpent are on original belts. Cant say the same about the gears on the shaft drive cars around here.
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Old 07-12-2004, 09:10 PM   #60
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i run an hpi rs4 3 and the differentials share the same parts with their trucks and rally kits. Even with an engine with three times standard power they have been bulletproof!
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