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Old 02-08-2009, 03:07 PM   #6991
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Originally Posted by PartTime View Post
Care to expand on that? I can think of 4, but 6?

DK
I think 6 options could be
long and short position without tweak screws
long and short position with tweak screws not touching chassis
long and short position with tweak screws touching chassis
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Old 02-08-2009, 03:34 PM   #6992
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Originally Posted by V12 View Post
I think 6 options could be
long and short position without tweak screws
long and short position with tweak screws not touching chassis
long and short position with tweak screws touching chassis
That is correct.
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Old 02-08-2009, 05:00 PM   #6993
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That is correct.
so what are the effect of these different settings.
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Old 02-08-2009, 05:29 PM   #6994
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So tonight was the first time so far that the BMI hasnt delivered as much as I hoped. I was handed it by 12L4's and 12R5's left and right today. Much of this is due to the driver, but I want to see if anyone has some other thoughts looking at the setup. A few weeks ago I set the fast laps and was eating up the competition with this setup on a more flowing track layout. Now I am slow coming off corners and fighting the car on this much more technical track.

The track was a Med bite track that had some fast runs but lots of 180 deg hair pins at the end of the straights, or just some slightly more open turns than a hairpin. Lots of technical stuff like a chicane that either requires a very perfect line or you need to dance around the plow disks a bit.

I found the car scrubbing too much speed in the corners, and not transitioning as I would have liked. The setup was:

Front:
5 degree block w/ 4 degree castor
.020 linear springs and Shure Lube 3
3.5mm ride height
servo flat w/ medium ballstuds on the steering blocks
Lilac front tires (Jacon Prism stock height)
.25mm droop (2 Shims above the upper pivot ball and one shim above the steering knuckle)
Servo mounted forward with the ball studs on the back of the servo saver
-1.5 Deg Camber
Neutral Toe
About 1 degree of toe in bump steer.

Rear:
Gold center shock spring
Silva shock w/ 60 wt Trinity oil
Medium ballstud on shock mount w/ 1.5mm worth of spacers
LiPo as far back as it can go
Shure Lube 4 in the tubes
Stock flex plates mounted in short position
No tweak screws
CRC Gray-Low pro-cut rear tires (at full size)
172mm rear width
1.5mm pod droop
Pod Level at ride height
3.5 - 4mm ride height

Novak 17.5 BL
Pinion 45T (was a bit over geared the motor came off at 150Deg in the main)
Spur: 78

Body - Parma Speed 8


I am seeing signs of the front being too soft, like lots of tire marks on the top of the inside of the body. I am thinking of going to a .22 linear spring.

I did have some initial traction roll issues that went away after a few laps. Any other thoughts?
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Old 02-08-2009, 05:30 PM   #6995
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Quote:
Originally Posted by V12 View Post
I think 6 options could be
long and short position without tweak screws
long and short position with tweak screws not touching chassis
long and short position with tweak screws touching chassis
Quote:
Originally Posted by level-4 View Post
so what are the effect of these different settings.
I think this how it goes....
long and short position without tweak screws
Soft setting
Full flex on both but the longer one is smoother/longer transision

long and short position with tweak screws not touching chassis
Medium setting, starts to flex then gets more stiffer, like a progressive spring.

long and short position with tweak screws touching chassis
Stiff setting
Shortens the flex plate, I would guess for little grip and bumpy surface...

How'd I do?
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Old 02-08-2009, 05:36 PM   #6996
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Full long w/ no set screws is softest
Full long/set screw but not touching chassis is a little stiffer and more progressive
Full long and set screw touching chassis is stiffest for long setting and most progressive

Short with no set screw is a little stiffer than long w/ set screw but not touching
Short w/ set screw is a little stiffer than w/ out set screw and again more progressive.
Showrt w/ set screw and touching the chassis is stiffest and most progressive
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Old 02-08-2009, 05:36 PM   #6997
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Quote:
Originally Posted by Clegg View Post
So tonight was the first time so far that the BMI hasnt delivered as much as I hoped. I was handed it by 12L4's and 12R5's left and right today. Much of this is due to the driver, but I want to see if anyone has some other thoughts looking at the setup. A few weeks ago I set the fast laps and was eating up the competition with this setup on a more flowing track layout. Now I am slow coming off corners and fighting the car on this much more technical track.

The track was a Med bite track that had some fast runs but lots of 180 deg hair pins at the end of the straights, or just some slightly more open turns than a hairpin. Lots of technical stuff like a chicane that either requires a very perfect line or you need to dance around the plow disks a bit.

I found the car scrubbing too much speed in the corners, and not transitioning as I would have liked. The setup was:

Front:
5 degree block w/ 4 degree castor
.020 linear springs and Shure Lube 3
3.5mm ride height
servo flat w/ medium ballstuds on the steering blocks
Lilac front tires (Jacon Prism stock height)
.25mm droop (2 Shims above the upper pivot ball and one shim above the steering knuckle)
Servo mounted forward with the ball studs on the back of the servo saver
-1.5 Deg Camber
Neutral Toe
About 1 degree of toe in bump steer.

Rear:
Gold center shock spring
Silva shock w/ 60 wt Trinity oil
Medium ballstud on shock mount w/ 1.5mm worth of spacers
LiPo as far back as it can go
Shure Lube 4 in the tubes
Stock flex plates mounted in short position
No tweak screws
CRC Gray-Low pro-cut rear tires (at full size)
172mm rear width
1.5mm pod droop
Pod Level at ride height
3.5 - 4mm ride height

Novak 17.5 BL
Pinion 45T (was a bit over geared the motor came off at 150Deg in the main)
Spur: 78

Body - Parma Speed 8


I am seeing signs of the front being too soft, like lots of tire marks on the top of the inside of the body. I am thinking of going to a .22 linear spring.

I did have some initial traction roll issues that went away after a few laps. Any other thoughts?
I would try a softer front tire. Maybe a 2x pink or magenta
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Old 02-08-2009, 06:23 PM   #6998
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Jason, I remember you saying somewhere that the reason you did not go with the Associated front end was due to caster problems you saw. Would you cre to elabriate on this, if you do not want to post it out, then could you pm me on this issue. I just want to know your take on it.
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Old 02-08-2009, 06:38 PM   #6999
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I will shoot it to you in a PM.
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Old 02-08-2009, 06:40 PM   #7000
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Quote:
Originally Posted by Clegg View Post
The setup was:

Front:
Lilac front tires (Jacon Prism stock height)

Rear:

CRC Gray-Low pro-cut rear tires (at full size)

3.5 - 4mm ride height

I am seeing signs of the front being too soft, like lots of tire marks on the top of the inside of the body. I am thinking of going to a .22 linear spring.

I did have some initial traction roll issues that went away after a few laps. Any other thoughts?
Looking at the items I highlighted in your setup, you may need to cut down the tires then readjust the ride height to 3.5-4mm. Running full size tires and getting 3.5-4mm ride height may be placing the tires too close to the body.
The tires rubbing will slow the car down drastically. When the front tires rub and slow down, or possibly stop all together, kiss your steering goodbye.

A smaller tire with the same ride height will give you better clearance to the body. This will keep the tires rotating. Hope this helps.
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Old 02-08-2009, 07:24 PM   #7001
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Thanks for the suggestions. I have a crappy truer now so I am going to shop around for a good one this week and get something a bit more solid.
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Old 02-08-2009, 09:48 PM   #7002
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Jason, I remember you saying somewhere that the reason you did not go with the Associated front end was due to caster problems you saw. Would you cre to elabriate on this, if you do not want to post it out, then could you pm me on this issue. I just want to know your take on it.
PM me that too if you would Jason thanks
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Old 02-08-2009, 09:52 PM   #7003
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1st club sunday back from the Birds. Had some bad luck in the qualifiers with a battery crapping out on me in the first one and the center pivot screw falling out in the 2nd so I ended up in the B main. We've got 9 or 10 pretty fast guys now though so I'm not to disappointed with that. In the main I ran good enough to finish 4th in the A too so things are going well Got a little more tweaking to do to get the car setup for asphalt again but the Birds setup ran pretty good for the most part. I just took out the tweak screws and that helped and I think moving the battery back up a little and the car will be perfect
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Old 02-09-2009, 03:46 AM   #7004
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I will shoot it to you in a PM.
Im interested also.

Is there any way to get one of your chassis custom cut for the R5 front end and center shock mount?

DK
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Old 02-09-2009, 03:53 PM   #7005
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PM me that too if you would Jason thanks
ok now im interested too. i have a good friend that runs the r5 and his caster is all messed up on the right side so maybe i can help him. i know josh cyrul was havin problems as well
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