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Old 10-08-2009, 11:54 PM   #7951
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Originally Posted by InspGadgt View Post
Yes I do...but I've had suggestions in the past to put a shim under the front of the hockey stick which does the same thing...and that's how Shreffler and Fairtrace had their cars setup at the Snowbirds...if it's good enough for them...it's good enough for me
I prefer to run with 0.5mm under the stand off rather than swapping them over. The 0.75mm difference in the standoffs is too much and makes the car erratic on the limit.
Also if shiming up the front of the flexplate it is necessary to shim the rear stand off to keep the cross brace square to the chassis.

Jason
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Old 10-09-2009, 01:23 AM   #7952
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To be honest I couldn't feel a difference in handling at all without a shim, with a shim, or with the stand-offs swapped. What I do notice though is when I have the stand-offs in the stock position I often get tweak in the hockey sticks when tightening the front screw that holds them on. But when I flip the stand-offs over so that I can tighten the screws with the chassis on a flat surface I get no tweak when tightening the screws. And the tweak I do notice. I've been running my car like this ever since Snowbirds on both carpet and asphalt and it's been working just fine. And as I said before...if it's good enough for Schreffler and Fairtrace...it's good enough for me
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Old 10-11-2009, 04:04 PM   #7953
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So today my friend Rob and I dropped our BMI's on the track to kick off the points series for the fall. I had a completely new setup on my car (stiff center spring, shimmed rear axel, new front suspension geometry, etc...), and Rob hadnt run his car in pretty much 6 months for more than a few spins around the track.

Good stuff for me:
The car didnt roll over nearly as much, if at all, but I could hear it raising a back tire on sharp transitions.

The car was stable in the high speed runs.

The car smoothed out some on breaking and going around tight corners.


The bad:
I lost all rear traction 5 minutes in, and developed snap over steer predominantly in one direction.


The rear may be due to the tires being very thin on foam, I chunked em pretty heavily so I trued them down a bunch to make them useable once again, but at that point they had just slivers of foam left.


Rob on the other hand, had an absolutely awful day with his 12RR (which I think hes going to post about himself). His car was very close to my setup, with the only real difference being that he is running the OE front shock mount, and he was running Lilac fronts and White rears. (vs my car running Black/Yellow)

His car was traction rolling (snap traction rolling at that) every corner he took even slow ones. Needless to say that was quite demotivating, and in general caused a shitty day over all on his side of the bench.


With all that said, I hope someone can provide some insight on some setup aspects and some deffinitions to wrap my head around. Some of these are quite simple, but so I can fully gather the combined effects of changes I am making this would help:
  • What does going to the stiffer location on the flex plates do? What part of handling is directly affected by that? Why would you stiffen or losen the flex plates?
  • By lowering the front shock mount, the geometry effectively makes the center shock stiffer right? What part of handling does that affect? What would you notice in a car to make the call on if you should change that spring, fluid, or angle?
  • Changing damper tube lube to thicker, or thinner lube - when would you go in either direction, and what effect on handling does that have? What would be a sign that you have too thin or to thick lube in the tubes?
  • Adding larger amounts of static caster, and dynamic caster does what to affect handling? What part of the cornering process is affected and to what extent?
  • Center ride height, what are some characteristics of center height being too low or too high?

Thanks folks, answers to these could be very valuable in trying to troubleshoot and set these cars up. As it stands I need to make up a bunch of time compared to others with other chassis.
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Old 10-12-2009, 02:25 AM   #7954
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Default DB12RR Spanish National Champion

Yesterday, was a good day for me and my DB12, i won the last National race and proclam National Champion , the car work very well, not the more fast in the track, but very easy to drive and smooth, classified in second position, with very good forward traction in the exit pass to the first and take a small lead that held until the end, in the second final,once again to take first place, but gave me a car is bumped from behin and i have to remount to last for 4th, the 3rd final are the more interesant, this time I could not overtake on the exit and rear of me is there 3 cars very fast, i put all of the car and me, for maintain my second place, this was a race of strategy,try to make a smooth ride to save battery, in the last minute, i put full trothle and gain 4 seconds, and final win for 3 seconds apart.
Im very happy with the car, is my first race with this car, and i need to work more in it, but i must say the result has been excellent, is the last race with NiMh tegnology, and now go to Lipo batteries, i expect even better with more practice and experience with this car.

I have to acknowledge the help you have given me many pilots who usually share our experiences and setups, thanks to all.

Greetings, Luis C.

My setup:
Attached Thumbnails
BMI's DB12R-db12rr.jpg   BMI's DB12R-podium2.jpg  
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Old 10-12-2009, 03:01 AM   #7955
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Congrats Luis! Great Job! Man that track sure looks nice behind you guys...wish we had something that nice out here.
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Old 10-12-2009, 04:40 AM   #7956
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Quote:
Originally Posted by Clegg View Post
So today my friend Rob and I dropped our BMI's on the track to kick off the points series for the fall. I had a completely new setup on my car (stiff center spring, shimmed rear axel, new front suspension geometry, etc...), and Rob hadnt run his car in pretty much 6 months for more than a few spins around the track.

Good stuff for me:
The car didnt roll over nearly as much, if at all, but I could hear it raising a back tire on sharp transitions.

The car was stable in the high speed runs.

The car smoothed out some on breaking and going around tight corners.


The bad:
I lost all rear traction 5 minutes in, and developed snap over steer predominantly in one direction.


The rear may be due to the tires being very thin on foam, I chunked em pretty heavily so I trued them down a bunch to make them useable once again, but at that point they had just slivers of foam left.


Rob on the other hand, had an absolutely awful day with his 12RR (which I think hes going to post about himself). His car was very close to my setup, with the only real difference being that he is running the OE front shock mount, and he was running Lilac fronts and White rears. (vs my car running Black/Yellow)

His car was traction rolling (snap traction rolling at that) every corner he took even slow ones. Needless to say that was quite demotivating, and in general caused a shitty day over all on his side of the bench.


With all that said, I hope someone can provide some insight on some setup aspects and some deffinitions to wrap my head around. Some of these are quite simple, but so I can fully gather the combined effects of changes I am making this would help:
  • What does going to the stiffer location on the flex plates do? What part of handling is directly affected by that? Why would you stiffen or losen the flex plates?
  • By lowering the front shock mount, the geometry effectively makes the center shock stiffer right? What part of handling does that affect? What would you notice in a car to make the call on if you should change that spring, fluid, or angle?
  • Changing damper tube lube to thicker, or thinner lube - when would you go in either direction, and what effect on handling does that have? What would be a sign that you have too thin or to thick lube in the tubes?
  • Adding larger amounts of static caster, and dynamic caster does what to affect handling? What part of the cornering process is affected and to what extent?
  • Center ride height, what are some characteristics of center height being too low or too high?

Thanks folks, answers to these could be very valuable in trying to troubleshoot and set these cars up. As it stands I need to make up a bunch of time compared to others with other chassis.
I need to get some machines running now as i just got into the shop. Please post your setup and i will post suggestions and answer your questions shortly
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Old 10-12-2009, 07:04 AM   #7957
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Clegg, im not a profesional driver, but i will try to help you, to my knowledge.

- For me, the flex plates act with a spring and T plate at same time, thin plates give more traction forward, more rear side bite but is lazy in transitions Right-left, in sttifer location, less traction, less rear side bite, and more fast in transitions.
- For the center shock, lowering the front, more inclined, give more on power steering, spring lighter give more rear traction, more off power steering, and litle on power steering, harder spring, less rear traction and more steering in mid-out of turns on power. The oil, is for balance front-rear, lighter oil, balance to rear (more rear traction).
- In side tubes, thicker grease increase front traction, more steering, slowed transitions and feel soften steering in fast transitions, if car is double steering on power you can go to thicker oil to slow reaction. Thiner oil, decrease front traction.
A tip, for know is you go to thicker or lighter, put the car in track and go with it 1-2 minutes, with stopwatcher take times, stop and removes one of the tubes, go away, and take times if are best you need lighter oil in tubes.
- i dont have more knowledge of this, i use same rule from touring car, less static caster, more turn in and lose straight line stability, more caster less turning off power, more on power. Reactive, decrease caster turn in, breaking and increase caster exiting of turn.

I hope help you a litle, i like what i corrected this wrong.

Greetings, Luis C.
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Old 10-12-2009, 07:38 AM   #7958
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Two things really jump out at me when I read that setup above.

First is the white rear tires with the Lilac fronts. If there's enough grip that the Lilac fronts are not pushing, then the whites and yellows are going to peel up and cause that hook. I run a minimum of grey rears with Lilac fronts. When I need more rear grip, I go to med. firm natural rubber. My fastest lap ever was with double pink rear Blackhawks and Lilac fronts and the rear ride hight .5 mm higher than the front. Magenta rear has the most grip for me. I would even run magenta all around on brand new dry Ozite carpet.The natural rubber has more side bite than the greys when you blip the throttle to finish a corner, so try 1 pr. before you stock up.

I rebuild my damper tubes when I get a lot of wheel lift. That seems to keep the rear flat in the corner.

The second thing is to true those rear tires down for high grip and radius the outside corner. Glue any peeling every run.

Good news though, my last Jaco Lilac sedan tires had a much better glue job than I've ever seen from them. It was almost like the stuff I used to glue TRC donuts back in the 1990's.

The 10 degree reactive front with centered spacers and -1.5 camber from the manual works perfectly with a blue center spring.
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Old 10-13-2009, 07:12 AM   #7959
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I rebuild my damper tubes when I get a lot of wheel lift. That seems to keep the rear flat in the corner.

The second thing is to true those rear tires down for high grip and radius the outside corner. Glue any peeling every run.

Good news though, my last Jaco Lilac sedan tires had a much better glue job than I've ever seen from them. It was almost like the stuff I used to glue TRC donuts back in the 1990's.

The 10 degree reactive front with centered spacers and -1.5 camber from the manual works perfectly with a blue center spring.
I concur with Eddie, with a couple more things to add for your consideration.

1) Maybe get in the habit of supergluing your sidewalls on all your tires, no matter the brand or compound. That way you get a consistent read on how their performance varies. Jaco's are the worst glued tire from the factory of all your choices, but can work well with good maintenance as Eddie stated. If you are not riding on the sidewall (square tires that haven't been radiused) or rolling the sidewall over (from a poor factory glue job) then you can base setup changes on the chassis performance knowing that bad tires won't be part of the equation. Without tire maintenance, you can get lost in chassis changes that seem to go no where (I've been there, it doesn't work).

2) Fresh tube lube is a must. If your car is double steering on exit or in chicanes, go one step stiffer with the lube.

3) Diff - If everything else is in good shape and you're hooking one way and not the other, probably a rebuild here would help a lot. The other thing that will make your Diff act weird is a bad rear bearing, double check those and hit 'em with some oil.

Hope you get your car sorted out!

Aaron
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Old 10-13-2009, 12:19 PM   #7960
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Originally Posted by InspGadgt View Post
Congrats Luis! Great Job! Man that track sure looks nice behind you guys...wish we had something that nice out here.
Thanks, this track is the Club ARCA in Madrid, are a very good track, this track are make important races, Nationals, Euros, Reedy Race,... etc, and are proposed for 2011 Euros.
This are about 450km from my home, 4h drive in car.
I read some race for you, and i see a photo dont remember is in this post pages back, and your make nice work in parking, it see a great track.

Greetings, Luis C.
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Old 10-13-2009, 02:11 PM   #7961
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Yeah we race in a parking lot and have had some great times. Unfortunately right now particpation is way down and I've had to cancel about half our races so far this season. I am working on fixing that. The main issue is about LiPo which we can't use at our race due to insurance reasons. I'm looking into a new parking lot and hopefully ROAR affiliation so that we can run LiPo and have a larger track.
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Old 10-13-2009, 04:10 PM   #7962
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Originally Posted by InspGadgt View Post
Congrats Luis! Great Job! Man that track sure looks nice behind you guys...wish we had something that nice out here.

+1 indeed congratulations on a big win .
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Old 10-13-2009, 05:05 PM   #7963
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Originally Posted by protc3 View Post
I need to get some machines running now as i just got into the shop. Please post your setup and i will post suggestions and answer your questions shortly
F:
.22
~5deg blocks (R5 front end which is set more or less at the same config as my L4 was).
Flat Servo
3.5mm height
-1 - -1.5 camber
Black Fronts

R:
Red spring, 60wt oil in silvia shock, with front shock mount moved backwards almost all the way and with the mounting position in the tall setting.
Standard flex plates, in long position
Tubes with Sure Lube 3 on em
Yellow Rears
3.5 - 4mm ride height
1mm droop
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Old 10-13-2009, 05:12 PM   #7964
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Thanks for the advice above!

So... one thing I havent been able to figure out, what is Double Steer ? Seems like something even a noob should know, but I dont! hehe
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Old 10-15-2009, 08:53 AM   #7965
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Default Lipo Edition Setups?

Looking for DB12RR Lipo Edition - Pro Driver - Current Setups (last 3 months) for 1S Stock & Superstock.

Would that help others here? anyone out there? anyone? Bueller, Bueller?
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