Pope
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There are many things that effect the proformance of your RC but none more than suspension setup. This is a indepth look into the princeables of suspension as applied to the savage. I will skip the aspects that are not changeable on a savage for the sake of time and the fact that there is nothing that can be done about it one way or the other.
First an over view of terms.
1. Suspension travel- The diffrence between the length of a fully extend suspension and a fully compressed suspension.
2. Toe- The angle of of the wheels in relation to straight forward and back.
3. Camber- the angle of the wheels in relation to a straight vertical line.
4. Caster- The angle of tilt forward or back of the line of rotation of the steering axis.
5. Ride height- the height that a truck sits at rest.
6. Droop- the amount of downward travel a suspension has below ride height.
Now to start lets begin with suspension travel and ride height
This is an often over looked aspect of suspension set up.
It is important to have all aspects of suspension travel set up correctly to have a truck that handles well.
First is your ride height. If you have your truck lifted way up in the air you will create a high center of gravity on your truck causing your truck to become very unstable in turns and at sideways angles. If you have your truck super low to the ground you will limit the amount of suspension compression you have and make your truck very unstable over rough ground.
(The sweet spot for ride height on a savage is right around the point at which the lower arms are level to the ground)
Next is compression beyond ride height. It is important that a trucks suspension be able to compress to absorb rises in the elevation of the ground when running do to washboard sections so that the truck itself does not bounce into the air everytime you hit a bump. The compression is also important when jumping; the compression of the suspension is what absorbs most of the impact of the landing.
(On a savage you want more suspension compression than your truck will alow before bottoming out. This extra compression is used when turning as when turning the roll of the chassis alows for the suspension to compress farther than it would be alowed to do when the truck is compressed equally)
Suspension Droop is another often overlooked aspect of suspension set up. Droop alows the tires to drop down when the elevation drops on do to a pot hole or over washboard sections of tracks. This alows the chassis of the truck to remain level and prevents loss of tracksion do to the truck bouncing. Droop also alows the suspension to decompress beyond ride height when jumping to alow more suspension travel when landing.
( You can limit both compression and droop with spacers placed either inside or outside of the shock body on the shock shafts. Inside will limit Droop, outside will limit compression.)
Another thing effected by these aspects of suspension is how a truck handles under breaking and acceleration.
When Breaking the weight of the truck is transferd to the front of the truck compressing the front shocks and causing the rear shocks to decompress. The amount of droop in the rear suspension determins how much weight can be transfered. The more droop the more weight will be transfered, the less droop the less weight will be transfered. Extra weight on the front tires when breaking will cause your truck to stop faster and pull through the turns under break do to the extra traction on the front wheels. Less weight transfer means less traction and a slower stop along with causing the truck to push trough turns under break.
When accelerating weight is transferd to the rear wheels causing the rear suspension to compress and the front to decompress. This leads to more traction on the rear wheels. The amount of weight transferd again relates to how much droop there is in the front. The more weight transfer the more traction you have under acceleration and the less traction on the front wheels. The more weight transfer the harder a truck will push in turns under power.
(There is a fine line on these setups and most is determinded by driving style. Do you break early and power through turns? Do you break late and power out of them? What line do you like to take? What tires are you using? The list goes on and on and keeping track on set up sheets of what you did and what worked and didn't work for you is going to make you much better in the long run. Being able to get this right is often what seperates first and last place.)
Now lets move on to Toe. Here is a fast break down of it.
Front toe in will increase stability on the straight aways, but it will increase drag causing you to be slower.
Toe out on the front improves cornering ability, but can make your vehicle twitchy on the straights. (adding a little expo will help with this making your imputs around center less sensitive)
Rear toe out is not used on either on or off road r/c's.
Rear toe in on all other vehicles helps to counteract over steer, improve off power steering and increase traction but again adds drag and decresses top speed.
(No more than about two degrees in or out on the front is needed and no more than two degrees on the rear. Note: The Hpi suspension conversions rear tie-rod elimanators have two degrees of toe-in built into them.)
Now for camber.
Camber effects the amount of the tire that contacts the ground either when turning or in a straight line.
Camber is used to counter act the roll of the truck when turning to keep the largest contact patch between the tires and the ground.
Raising or lowering the points at which the Camber links aka top a-arm intersect will effect how camber changes in a turn.
The more of an angle downwards towards the chassis the more on power steering you will have as it causes the camber angle to incresses as the suspension compresses. This also slows the response of your truck to your steering inputs making the truck less twitchy.
(The HPI suspension conversion increeses the downwards angle of the camber link by adding a cross brace that drops down the inside conection point.)
The less of an angle downwards towards the chassis the more off power steering you will have and the faster your truck will respond to steering inputs.
Next is Caster.
For the savage there is only two options for caster and it is only avalible in the front of the truck so I will do this in terms of one verses the other.
The only two settings on a savage are either stock at 0 degrees or the angle avalible with the HPI suspension conversion.
Lets look at what happens with the Suspension conversion.
The added caster slows down steering, increases stability in the corner and improves self-centering of the steering on straights.
It incresses both in and out of corner on power steering alowing you to take turns at a higher rate of speed.
Also when running the Suspension conversion you do not need as much camber because of the change in axis of the outside tire.
(How to tell if you have the corect camber angle: if the outside of your tire is wearing more than the inside you need more camber if the inside is wearing more than the outside of the tire than you need less.)
First an over view of terms.
1. Suspension travel- The diffrence between the length of a fully extend suspension and a fully compressed suspension.
2. Toe- The angle of of the wheels in relation to straight forward and back.
3. Camber- the angle of the wheels in relation to a straight vertical line.
4. Caster- The angle of tilt forward or back of the line of rotation of the steering axis.
5. Ride height- the height that a truck sits at rest.
6. Droop- the amount of downward travel a suspension has below ride height.
Now to start lets begin with suspension travel and ride height
This is an often over looked aspect of suspension set up.
It is important to have all aspects of suspension travel set up correctly to have a truck that handles well.
First is your ride height. If you have your truck lifted way up in the air you will create a high center of gravity on your truck causing your truck to become very unstable in turns and at sideways angles. If you have your truck super low to the ground you will limit the amount of suspension compression you have and make your truck very unstable over rough ground.
(The sweet spot for ride height on a savage is right around the point at which the lower arms are level to the ground)
Next is compression beyond ride height. It is important that a trucks suspension be able to compress to absorb rises in the elevation of the ground when running do to washboard sections so that the truck itself does not bounce into the air everytime you hit a bump. The compression is also important when jumping; the compression of the suspension is what absorbs most of the impact of the landing.
(On a savage you want more suspension compression than your truck will alow before bottoming out. This extra compression is used when turning as when turning the roll of the chassis alows for the suspension to compress farther than it would be alowed to do when the truck is compressed equally)
Suspension Droop is another often overlooked aspect of suspension set up. Droop alows the tires to drop down when the elevation drops on do to a pot hole or over washboard sections of tracks. This alows the chassis of the truck to remain level and prevents loss of tracksion do to the truck bouncing. Droop also alows the suspension to decompress beyond ride height when jumping to alow more suspension travel when landing.
( You can limit both compression and droop with spacers placed either inside or outside of the shock body on the shock shafts. Inside will limit Droop, outside will limit compression.)
Another thing effected by these aspects of suspension is how a truck handles under breaking and acceleration.
When Breaking the weight of the truck is transferd to the front of the truck compressing the front shocks and causing the rear shocks to decompress. The amount of droop in the rear suspension determins how much weight can be transfered. The more droop the more weight will be transfered, the less droop the less weight will be transfered. Extra weight on the front tires when breaking will cause your truck to stop faster and pull through the turns under break do to the extra traction on the front wheels. Less weight transfer means less traction and a slower stop along with causing the truck to push trough turns under break.
When accelerating weight is transferd to the rear wheels causing the rear suspension to compress and the front to decompress. This leads to more traction on the rear wheels. The amount of weight transferd again relates to how much droop there is in the front. The more weight transfer the more traction you have under acceleration and the less traction on the front wheels. The more weight transfer the harder a truck will push in turns under power.
(There is a fine line on these setups and most is determinded by driving style. Do you break early and power through turns? Do you break late and power out of them? What line do you like to take? What tires are you using? The list goes on and on and keeping track on set up sheets of what you did and what worked and didn't work for you is going to make you much better in the long run. Being able to get this right is often what seperates first and last place.)
Now lets move on to Toe. Here is a fast break down of it.
Front toe in will increase stability on the straight aways, but it will increase drag causing you to be slower.
Toe out on the front improves cornering ability, but can make your vehicle twitchy on the straights. (adding a little expo will help with this making your imputs around center less sensitive)
Rear toe out is not used on either on or off road r/c's.
Rear toe in on all other vehicles helps to counteract over steer, improve off power steering and increase traction but again adds drag and decresses top speed.
(No more than about two degrees in or out on the front is needed and no more than two degrees on the rear. Note: The Hpi suspension conversions rear tie-rod elimanators have two degrees of toe-in built into them.)
Now for camber.
Camber effects the amount of the tire that contacts the ground either when turning or in a straight line.
Camber is used to counter act the roll of the truck when turning to keep the largest contact patch between the tires and the ground.
Raising or lowering the points at which the Camber links aka top a-arm intersect will effect how camber changes in a turn.
The more of an angle downwards towards the chassis the more on power steering you will have as it causes the camber angle to incresses as the suspension compresses. This also slows the response of your truck to your steering inputs making the truck less twitchy.
(The HPI suspension conversion increeses the downwards angle of the camber link by adding a cross brace that drops down the inside conection point.)
The less of an angle downwards towards the chassis the more off power steering you will have and the faster your truck will respond to steering inputs.
Next is Caster.
For the savage there is only two options for caster and it is only avalible in the front of the truck so I will do this in terms of one verses the other.
The only two settings on a savage are either stock at 0 degrees or the angle avalible with the HPI suspension conversion.
Lets look at what happens with the Suspension conversion.
The added caster slows down steering, increases stability in the corner and improves self-centering of the steering on straights.
It incresses both in and out of corner on power steering alowing you to take turns at a higher rate of speed.
Also when running the Suspension conversion you do not need as much camber because of the change in axis of the outside tire.
(How to tell if you have the corect camber angle: if the outside of your tire is wearing more than the inside you need more camber if the inside is wearing more than the outside of the tire than you need less.)