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Old 08-03-2005, 05:32 PM   #7981
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Old 08-04-2005, 04:29 AM   #7982
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Hi guys, Thanks for your responses. First of all killswitch any extra setups especially from actual bmitc3's would be great, thanks.
Joe B , I have placed the car on a tweak station and is always out a fair bit , but i try to dial it back in with shock adjustment. I am running the 3+2 rear block already. What i've found is that some of the stand offs are a little damaged, thats also why I'm tring to source new ones, when tightened up they seem to pull one corner of the suspension up, creating the tweak in my opinion. But I will try to check the gearbox housings as well. This is my current setup as follows, somethings might seem weird but it 's the best I've got it so far:
Frt Camber 1.* all round , 0* kickup, 4* caster, std akerman, 60wt oil all round( to slow twitchiness) blue springs, outside hole on lower arms, rear shock tower on frt midle hole, 0* toe, camber link upper inner & std on hub. Frt swaybar original kit one , dont have the other thicknesses.
Rear 3* toe , 2* antisqwat, outside hole on lower arms, and on rear tower, cam as above, link lower inner( upper hole makes rear completly loose) upper outer on std hub, shock oil as above, green springs( the softer I went the better the traction I felt!). droop #6 frt, #4-3 on the rear, ride height 5mm frt 5.5-6mm rear ( trying to look after that beautiful chassis), Mazda 6 Protoform and Blitz bodies, batteries fwd most times. Irs lite drives frt&rear ( find hard not to get some slip , they dont feel so good when tighten right up.) But do prefer oneway up frt but switch back to diff when running mod to tame it down a little. Sorex tyres mainly b med inserts.
Think thats about it , Sorry bout all the babble but searching for that right advice! As I said I think it could be mainly tweak thats why I'm after those replacement posts, and seems to break traction mainly off power, crossing the apex or entering the corner! . Hope this gives you guys something to go off so I can find out what I'm doing wrong or whats wrong with the car!!!! Speaking bout parts Jason did you find those posts and upper deck I'm keen let me know. Any advice would be great got to go catch you's later. Karl.R.
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Old 08-04-2005, 05:09 AM   #7983
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Hey Karl..(after you cure the tweak issue).....60w oil all the way around In my opinion is "way" too thick for medium grip (or even slightly better) asfault with the stiff 3mm upper and 3mm lower BMI TC-3 kit...especially for the rear...Try 40w in the front.....30w to 40w Max in the rear(try 30 first) , 2 hole pistons front and rear (if not already)...Try "No" rear swaybar for stock and 19turn...and go back to a silver rear spring, and if the problem still exists (which I don't think it will) go back to your green spring....I run a set-up Just about the same as yours after you make the changes...(except I run 4.5mm ride height in front and 5mm in the rear).....and my car is dialed in really good for medium to high grip asfault on rubber tires, I switch back and fourth between a oneway and a spool ,and it runs great without any additional changes.....let us know how it works out....good luck .......Joe
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Old 08-04-2005, 02:25 PM   #7984
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I was blessed to be able to test the "TeamGP BMI FK05 Asphalt Edition" more the last two days. This chassis is definitely a different animal compared to the original FK05 chassis.

After some brainstorming on Monday night, I came up with a baseline setup that incorporates the following setup requirements.

* Front end with very little movement due to braking and acceleration forces (no diving or lifting up) - The BMI chassis has added a significant amount of static weight onto the front axle which is great for overall steering. But the extra weight, coupled with the softer springs used for rubber racing, can make the front end dive too much and unload the rear end on corner entry. It can also make the front end rise up too much and lose the steering advantage due to weight transfer backwards on corner exit. Even though I was setting up this car for asphalt racing, I decided to stay with my carpet setup preference and force the front end to stay as close to ride height as possible. To implement this requirement, I kept the 1.5d high roll center anti-dive arm mounting positions and set the front downstops to a value that would keep the front end chassis up travel limited to 1.5mm under acceleration. With a 5.5mm front ride height, the correct downstop setting was 1. FYI, the most common setups have downstop settings that allow for 2.5 to 3.5mm of up travel.
* Flat cornering front end - With the extra weight over the front axle, chassis roll is not as necessary for steering and too much roll could reduce the "flickability" responsiveness of the FK05's slim design. Of course we all know that the less roll you have, the faster your corner speeds will be if you have sufficient grip. Again, I decided to stay with my carpet setup preference and make the entire front end "pitch" into corners in more of a flat line in between the wheel hubs, rather than "rolling" through the motion of both arms. To implement this requirement, I kept the 2mm anti-roll bar on and meticulously adjusted the mounts to exert the same amount of force to both front arms.
* Stiff chassis with all side posts - Call me crazy, but the thought of a flexible chassis brings to mind the word inconsistency. Not because it doesn't work, but because you would need some pretty expensive CAD software to accurately measure the handling differences and amount of flex needed in order to tune in a consistently predictable manner. Therefore, I have decided to invest the time to see if I could tune the suspension for adequate and consistent grip on asphalt with rubbers using the very stiff BMI standard chassis setup.
* 0 degree front toe-out - I prefer to keep the wheels straight and twitch free for minor steering corrections down the straights and use other tuning options to provide more initial turn-in grip
* Very active rear end - Moving the weight forward on the BMI chassis has left the rear end very light. Therefore, balanced grip would have to be "actively" induced in the rear for all 3 stages of cornering using the three of the most influential forces (roll center, springs and downstops) in tuning weight transfer through the suspension itself. To provide good initial turn in steering I set the rear downstops to 0 in order to provide 3.5mm of rear chassis up travel under deceleration. The standard rear yellow springs and the low roll center position for the arms were used to make sure the light rear would give enough grip mid corner.
* I've wanted to test the new RP30's more, so they were thrown into the mix as well. I thought this might be like adding a dash of central american chili peppers to a meal your serving for the first time, but thats what I like to do.

The full baseline setup can be found here:

http://www.teamxray.com/xforum/xform...6&setup=t1fk05

Tuesday - The first impression can be summed up in two words. Power slide. The car very briefly pushed entering the corners, but quickly hooked up and was on rails when entering both smoothly and very surprisingly with heavy brakes. Mid corner was great as it rolled through the apex very well, but exiting soon became an exercise in concentration to consistently counter steer and straighten it up correctly without letting off the gas. There wern't any full 180's completed, but it reminded me of the times I used to power slide my old 78 Chevy Malibu (w/455 Olds Rocket, if you know what I'm talkin about ) as a teenager back in NC (a true test of concentration and game of chicken with yourself ). Back in the bat cave, eyeballing the rubbers and taking temp readings on the middle and inside/outside edges revealed that the camber settings were good. I tried correcting the initial push by adding 1mm more rear chassis up travel through the rear droop screws, but it made the rear end unload even more and getting on the gas became a little frightening. So I decided to work on the push problem last and started tackling the power slide issue. Throughout the rest of the day I tried several combinations of front & rear shock piston hole positions as well as different front springs and their mounting positions, but I was only able to get rid of the power slide 80 percent of the time. Changing from 2.5d to 3d rear toe helped out a lot, but the consistency just wasn't there yet. A quick review of the days test results revealed I needed to brainstorm some more on how to get rid of moderate initial under steer off-power and moderate overseer on-power.

After a needed meal I figured that the combination of a flat riding front end and a very light rear end must be preventing the weight from shifting forward under deceleration and backward on acceleration. The front didn't push enough off-power to warrant taking out the anti-dive and I certainly had enough steering mid corner and exit, so I decided to leave the front end alone. Finally, after using my own imagination for a CAD picture of the car in motion (not enough $ or intellect to use the real thing ), I came up with something I had never tried nor had ever been recommended by anyone. Why not use "pro" squat to allow the lighter rear end to rise up faster to cure the initial push and also squat down faster and with more force to cure the on-power overseer. I decided to implement this option and maintain a low rear roll center by raising the rear hinge pin holder of the rear arms up on hole and leave the front hinge pin holder in the lowest hole. An hour, a few modifications, a full car alignment and a good tire cleaning/saucing later and the car was ready for the next days testing. I was ready for bed.

Wednesday - Wow! The car was finally balanced! But as I started to push harder in the turns, the rear would rotate just a hair too much at mid corner. A quick check of the tires revealed that the rear needed .5d more static camber. Problem fixed. But with the added grip, the rear started bottoming out too quickly under hard acceleration in fast sweepers and bumps or tighter steering corrections would cause it to lose traction with zero arm up travel left to soak up the forces. I decided to put on white springs in the back and move the rear lower mounting positions to the outside hole. A change to light blue springs in the front proved to be the best combination in order to keep the balance as well. The bottoming out was cured, and a little more testing revealed that inclining all of the shocks one more hole than the stock setup provided even tighter cornering lines without too much rear roll. This was great since I was testing on a low to medium grip surface and a simple change of standing them up one hole should work for higher grip asphalt tracks. *Thanks BMI for the great work on changing the rear shock tower mounting holes to line up better.* With all of the previous issues now gone, I moved on to the final test of simulating a medium speed chicane taken on the gas. This revealed that the rear was just a tad unstable under acceleration in quick left/right transitions if I wasn't very smooth with the steering wheel. After trying a few changes with the shocks, that didn't work, I decided to ditch the well used set of RP30's for my current favorite combination of CS27's in the front and 22's in the rear. Voila! The car was as perfect as can be without being race tested. I plan on running a few packs again this evening to make sure yesterday wasn't just a fluke. Here's the final setup from yesterday and a few pics of the TeamGP BMI FK05 Asphalt Edition.

http://www.teamxray.com/xforum/xform...7&setup=t1fk05
Attached Thumbnails
BMI Racing Discussions-bmi_asphalt_fk05_top.jpg   BMI Racing Discussions-bmi_asphalt_fk05_front.jpg   BMI Racing Discussions-bmi_asphalt_fk05_left.jpg   BMI Racing Discussions-bmi_asphalt_fk05_rear.jpg   BMI Racing Discussions-bmi_asphalt_fk05_right.jpg  

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Old 08-04-2005, 02:26 PM   #7985
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A few more pics...
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BMI Racing Discussions-bmi_asphalt_fk05_left_front.jpg   BMI Racing Discussions-bmi_asphalt_fk05_left_rear.jpg   BMI Racing Discussions-bmi_asphalt_fk05_bottom.jpg  
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Old 08-04-2005, 02:39 PM   #7986
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does the missing screw in the rear bulk head make it handle better? just messin w/ ya
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Old 08-04-2005, 02:43 PM   #7987
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Quote:
Originally Posted by Little Bahnatka
does the missing screw in the rear bulk head make it handle better? just messin w/ ya
Not quite sure. But the BMI still doesn't flex without it, even with my spidy strength twisting it.
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Old 08-04-2005, 04:14 PM   #7988
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team gp,

wow,thanks for the unbiased in depth review buddy.sounds like you are doing alot of serious testing buddy.i really appreciate it.
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Old 08-04-2005, 04:19 PM   #7989
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rs911,

i do have the top deck.i have the short standoffs but none of the long ones left.i can make you new ones if you need them.

thanks,
jason
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Old 08-04-2005, 04:24 PM   #7990
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Jason..

you have a PM
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Old 08-04-2005, 11:17 PM   #7991
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rs911
My rubber tire asphalt setup is exactly like yours with the changes Joe B mentioned. The only difference is when I run stock or 19t I run a .055 swaybar from BRP. I've tried no rear swaybar, but my lap times were faster with the .055 on the rear. I still run the plastic outdrives in the rear and have never really had any problems with them. I also prefer a one way to a spool.
If I run foams on asphalt here's my baseline setup
front end:
caster 2*, kickup 2*, camber -1.5*, toe -.5*, 5mm ride height, std ackerman, no bump steer shims, outside hole on tower, inside hole on arm, stock camber hole on tower, droop set at 4, 50wt oil, #2 pistons, copper springs, .078 swaybar, 40 shore 28mm foams (usually 57-58mm dia.)
rear end:
3+2 block, camber -2*, 5mm ride height, middle hole on tower, inside hole on arm, stock camber hole on tower, droop set at 3, 35wt oil, #2 pistons, gold springs, .063 swaybar, 35 shore 30mm foams (usually 57-58mm dia.)
other stuff:
battery to the front, mazda 6, traction compound depends on surface on race day, short wheelbase (local track has one long straight), also I drive very agressively
As far as loosing traction off power the best thing I ever learned about racing rc cars is they like to stay on power, even if its just barely on power. I used to fight my cars around the track until our local fast guy taught me to stay on the throttle thru the turns. My lap times instantly went down. I went from being a B and C main racer to an A main regular. I know guys that set their trim to barely pull even when off the trigger that way their car doesn't get out of shape, especially when running a one way. When you let completely off throttle your suspension unloads and your car can become very unsettled. When running a one way try to do all of your braking in a straight (especially if you have tweak problems) and then throttle thru the turns. Learn to use all of your trigger motion to your advantage. I'll post a carpet setup tomorrow at work (have to put the car on the setup gauges because I can't find my sheet-gotta love managing a hobby shop) Let me know if that helps.
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Old 08-05-2005, 12:40 AM   #7992
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I sent you a PM.
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Old 08-05-2005, 05:36 AM   #7993
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Thanks Joe B and killswitch for the setups and I'll try those changes Joe, and let u know how I go . Fingers crossed Jason , thanks for the reply, I'm only needing the short standoffs anyway, my long ones are fine. I'd also like the upper deck if possible, even if just to try. Could you please let me know how much for both including ups or similar posting to Queensland , Australia . Pm me if it is more convienent. Thanks once again I'll let u know how I go Bye for know. Karl.
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Old 08-05-2005, 08:18 AM   #7994
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No problem Jason. I love to test. Now hopefully I can translate it into a good finish for the upcoming Rockville, MD race. If the setup doesn't work at all, at least I have a better understanding of how all of these tuning options will affect the BMI outfitted FK05, which should allow me to dial it in quickly during Friday's practice day.

Thursdays test results:

Now that the car was hooked, with CS27's on the front and CS22's on the rear, I dialed up the EPA on my transmitter to see how far I could go until the rear end would brake loose. At 80% the arm of the inside steering block started touching the front anti-roll bar mount screw and the rear was barely giving a hint of initial over steer after getting on the gas.

Then the thought occured to me that I still had the QC2's punch control set to 5 for "mega punch" (gotta love those european guys vocabulary ) with stock motors. So I dialed it down to 3 and I found that I could now get on the gas earlier and the over steer was gone. But getting on the gas earlier gave me higher speeds exiting the corner and there was a noticeable abrupt push at the end of the exit arc where I assume the QC2 was letting go of the leash right in the heart of the double wind motors peak power (I have it geared just a tad on the high side). I dialed the punch control down to 2 and the push started to go away, but dialing it down to 1 for "smooth" power finally tamed the Fantom 10 x 2. I also noticed that the higher corner speeds was wearing the insides of the rears slightly so I reduced the camber from 1.5d to 1.25d. Keep in mind that with the shortest rear camber links and 3mm spacers under the ball ends, camber gain is very high and .25d is a big difference.

Next I chose to dial in the right amount of grip gained from the dampening. The car was already set at two holes open, so I clicked them over to one hole open (gotta love the adjustable Xray shocks & yes I know they are a pain for some to build though ) and the car started drifting noticeably on corner exit as I could see that all four tires were struggling to stay in contact with the road. I moved on to the other extreme and clicked all of them over to four holes open and the car was stuck in the corners like glue with a noticeable difference in scrubbing a lot of speed. Clicking them over to three holes open loosened the car up just enough for much faster corner speeds and with enough traction to provide a tighter steering arc than was present with the initial two holes open. With AE 40wt oil, this should be the equivalent of using Xray 30wt oil with all four holes open.

With one pack left and 5 minutes to spare, I threw on a good set of RP30's for grins and the car was in another class. Dialing down the punch control and opening up another hole on the shocks must have glued the rear end to the road like CA sticks foam to the fingers. And the RP's added steering that was equivalent to a slot cars. The cornering radius was cut down by a third on corner entry with heavy braking AND corner exit with a trigger happy throttle finger. Zero sliding in the rear and no pushing in the front should make late breaking for the inside pass more fun and less hair raising.

I took it with me to my friends house (Barbecue...MMmmm ) where the grip of the smoother asphalt was really low due to a little bit of sand. He's back from Iraq on two weeks R&R and of course I had to demonstrate the mean machine to him for a BRIEF minute. I was surprised to see that it coped well with the low grip as the car was still balanced with a little drifting action that was controllable with the throttle. I'd hazard a guess that for very low traction tracks, opening up the shock pistons to four holes or switching to white springs in the front and blue/green in the rear would give enough grip.

Updated setup:

http://www.teamxray.com/xforum/xform...7&setup=t1fk05
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Old 08-05-2005, 08:36 AM   #7995
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Does anyone know if there is a word limit for posts?
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