Xray T2'007
02-27-2007, 08:54 AM
#1998
Tech Master
iTrader: (39)
Wheel wobble when turning..... Runnig a multi-diff as a oneway and when I turn the wheel in either direction the inside wheel wobbles. It does this either going slow or under power. Does anyone know what causes this or how to fix it? I had the same problem with an old FK05. The 007 is new with a days racing on it. The servo is fine. I tried o-rings in the outdrives. I tightened up as much slop as was possible. I tried putting on new outdirves and cvds. They are not bent. I changed the bearings and made sure they were smooth. The belt is not too loose.
02-27-2007, 11:30 AM
#2002
Originally Posted by Jamie Hanson
Wheel wobble when turning..... Runnig a multi-diff as a oneway and when I turn the wheel in either direction the inside wheel wobbles. It does this either going slow or under power. Does anyone know what causes this or how to fix it? I had the same problem with an old FK05. The 007 is new with a days racing on it. The servo is fine. I tried o-rings in the outdrives. I tightened up as much slop as was possible. I tried putting on new outdirves and cvds. They are not bent. I changed the bearings and made sure they were smooth. The belt is not too loose.
avid
02-27-2007, 01:10 PM
#2004
[QUOTE=Dane]
Thats a question that probably needs answering by Juraj Hudy. 
I would suspect its a combination of ease of access, as well as a tuning aid for quick track width changes (differing thickness hexes).
Originally Posted by teamgp
Not sure what your asking here.
What I mean is the hexes that the wheels connect to.
What I mean is the hexes that the wheels connect to.
I would suspect its a combination of ease of access, as well as a tuning aid for quick track width changes (differing thickness hexes).
02-27-2007, 01:21 PM
#2005
Originally Posted by corradopsi
jamie, are you sure your not using too much steering throw? i know i have that problem when i try to use too much dual rate, and its even worse if you use a spool.
You shouldn't be using much considering your oval background.
Seriously, it probably has to do with too much EPA/dual rate. Disconnect the ESC leads to the motor (leave it in the car though) and put the car on a setup station with at least a barely charged battery to test the steering throw. Then turn it on, turn to full lock each way and record the amount of degree's for both the inside and outside wheel in both right and left directions.
IMO (from extensive testing), the inside wheel shouldn't turn more than approximately 16.5 degrees. There also shouldn't be anymore than a 2.5 degree difference between the inside and outside wheels when turned to full lock. If there is more of a difference, the inside wheel usually drags in the corners A LOT.
If the inside wheel is turning more than 16.5d and the outside wheel is turning at least 14d, then just turn down your EPA/dual rate until the inside wheel turns no more than 16.5d at full lock.
If the inside wheel is turning more than 16.5d and the outside wheel is turning less than 14d, then first you'll need to reduce the cars ackermann. Then reset the EPA for both sides so that the inside wheels don't go over 16.5d at full lock.
02-27-2007, 01:33 PM
#2006
One last thing...
The less difference between the inside and outside wheels at full lock, the less the inside wheel will drag mid corner.
The less grip the more difference you normally need for on-power steering, due to the tires slip angles. For rubber tires usually upwards of 1.5d to 2.5d difference works. For foam tires usually only 1d to 2d difference is needed.
You'll find out how much the inside tire drags really quick if you have a one-way up front.
Too much drag = abrupt mid corner oversteer.
With a front diff you don't get oversteer and the problem is somewhat masked. You can mainly tell when following a well setup car as your mid corner speed will be much slower than the other car.
The less difference between the inside and outside wheels at full lock, the less the inside wheel will drag mid corner.
The less grip the more difference you normally need for on-power steering, due to the tires slip angles. For rubber tires usually upwards of 1.5d to 2.5d difference works. For foam tires usually only 1d to 2d difference is needed.
You'll find out how much the inside tire drags really quick if you have a one-way up front.
Too much drag = abrupt mid corner oversteer.With a front diff you don't get oversteer and the problem is somewhat masked. You can mainly tell when following a well setup car as your mid corner speed will be much slower than the other car.
02-27-2007, 03:38 PM
#2007
Based on experience from other cars:
-Plastic hexes will eventually wear out, which can cause them to bind the suspension bearings.
-Standard aluminum hexes will not wear out like this, but they are annoying because they can fall off really easy during maintenance.
-Aluminum clamping hexes will not wear out or fall off
.
-Plastic hexes will eventually wear out, which can cause them to bind the suspension bearings.
-Standard aluminum hexes will not wear out like this, but they are annoying because they can fall off really easy during maintenance.
-Aluminum clamping hexes will not wear out or fall off
.
02-27-2007, 11:09 PM
#2008
Originally Posted by teamgp
Jamie,
You shouldn't be using much considering your oval background.
Seriously, it probably has to do with too much EPA/dual rate. Disconnect the ESC leads to the motor (leave it in the car though) and put the car on a setup station with at least a barely charged battery to test the steering throw. Then turn it on, turn to full lock each way and record the amount of degree's for both the inside and outside wheel in both right and left directions.
IMO (from extensive testing), the inside wheel shouldn't turn more than approximately 16.5 degrees. There also shouldn't be anymore than a 2.5 degree difference between the inside and outside wheels when turned to full lock. If there is more of a difference, the inside wheel usually drags in the corners A LOT.
If the inside wheel is turning more than 16.5d and the outside wheel is turning at least 14d, then just turn down your EPA/dual rate until the inside wheel turns no more than 16.5d at full lock.
If the inside wheel is turning more than 16.5d and the outside wheel is turning less than 14d, then first you'll need to reduce the cars ackermann. Then reset the EPA for both sides so that the inside wheels don't go over 16.5d at full lock.
You shouldn't be using much considering your oval background.
Seriously, it probably has to do with too much EPA/dual rate. Disconnect the ESC leads to the motor (leave it in the car though) and put the car on a setup station with at least a barely charged battery to test the steering throw. Then turn it on, turn to full lock each way and record the amount of degree's for both the inside and outside wheel in both right and left directions.
IMO (from extensive testing), the inside wheel shouldn't turn more than approximately 16.5 degrees. There also shouldn't be anymore than a 2.5 degree difference between the inside and outside wheels when turned to full lock. If there is more of a difference, the inside wheel usually drags in the corners A LOT.
If the inside wheel is turning more than 16.5d and the outside wheel is turning at least 14d, then just turn down your EPA/dual rate until the inside wheel turns no more than 16.5d at full lock.
If the inside wheel is turning more than 16.5d and the outside wheel is turning less than 14d, then first you'll need to reduce the cars ackermann. Then reset the EPA for both sides so that the inside wheels don't go over 16.5d at full lock.
So i went and tried mine to see what mine is and at full lock, mine is 27d on the inside and 18d on the outside.
To acheive your 16.5d on the inside tyre i had to turn down the dual rate from 100% down to 65% now if i did that, to me you are NEVER gunna have enough steering / steering lock.Am i setting it up wrong or do you guys always turn the steering down that much.
Also my xray is kit set up in regaurds to ackerman and i set it up so 100% steering throw just touches the carster blocks and the 27d inside tyre and 18d on the outside is what it reads at kit.
What are everybodies thoughts.
cheers.
02-28-2007, 01:45 AM
#2009
Originally Posted by NOOB-SMOKE
I was just looking at how you set up your steering and what you say is at full lock the inside wheel should not go over 16.5d when at full lock.
So i went and tried mine to see what mine is and at full lock, mine is 27d on the inside and 18d on the outside.
To acheive your 16.5d on the inside tyre i had to turn down the dual rate from 100% down to 65% now if i did that, to me you are NEVER gunna have enough steering / steering lock.Am i setting it up wrong or do you guys always turn the steering down that much.
Also my xray is kit set up in regaurds to ackerman and i set it up so 100% steering throw just touches the carster blocks and the 27d inside tyre and 18d on the outside is what it reads at kit.
What are everybodies thoughts.
cheers.
So i went and tried mine to see what mine is and at full lock, mine is 27d on the inside and 18d on the outside.
To acheive your 16.5d on the inside tyre i had to turn down the dual rate from 100% down to 65% now if i did that, to me you are NEVER gunna have enough steering / steering lock.Am i setting it up wrong or do you guys always turn the steering down that much.
Also my xray is kit set up in regaurds to ackerman and i set it up so 100% steering throw just touches the carster blocks and the 27d inside tyre and 18d on the outside is what it reads at kit.
What are everybodies thoughts.
cheers.
02-28-2007, 02:56 AM
#2010
TeamGP brings up a good point with actual degrees of steering throw. its something that a lot of us just take for granted and never really know what the fast guys are using. i wish this measurement was included on setup sheets.
for those that have setup stations, what are your measurements for inside and outside wheels maximum steering angle? post them here for comparisons sake. and include whether your on rubber or foam tires
iirc, mine are 17* outside and 23* inside. rubber tires.
TeamGP, can i use the ackerman settings to reduce inside steering angles and still retain outside angle so i still have plenty of steering for tight sections of track? id assume moving the quick ackerman horn on the servo saver forward would give the desired effect.
for those that have setup stations, what are your measurements for inside and outside wheels maximum steering angle? post them here for comparisons sake. and include whether your on rubber or foam tires
iirc, mine are 17* outside and 23* inside. rubber tires.
TeamGP, can i use the ackerman settings to reduce inside steering angles and still retain outside angle so i still have plenty of steering for tight sections of track? id assume moving the quick ackerman horn on the servo saver forward would give the desired effect.