wyd

iTrader: (51)

protc3 looks like your busy as every!!!!!!!! Nice!!!!!!!

StewartFan20

iTrader: (4)

This may have been asked before. If it has I apologize. But, does the Pro4 BMI chassis help eliminate tweak. I have to be extreemly careful when putting on the top deck of my stock pro4 chassis. Otherwise, the chassis will tweak and will be loose turning left and tight turning right.

wyd

iTrader: (51)

WHen i ran my BMI Pro4 I didn't have any problems with tweaking. I think with any double deck car tweak can be a problem but I know with my BMI setup it was never an issue. Set the car up and run it. Even after a big hit the tweak was still fine.

Brian

UnderDaHill

Would screwing on the top plate while the car is sitting on it's tires cause you to "Capture" a tweak? I've never assembled a car off a stand but I could see how setting a tweaked car on it's tires and then putting on the top plate might kind of lock a tweak into the chassis. Does that make any sense?

Zach P

I use to have that problem with my xray. Just have someone push your car down while pushing the front and rear in opposite directions while you screw the top deck on. This eliminates top deck tweak.

StewartFan20

iTrader: (4)

I don't put the top plate on with the wheels on in. I will put the chassis on something flat (like glass), hold it down the best I can and put the top deck on it. Most of the time this works, I just need to be very carful. I am wondering if a hard enough hit will put a tweek in the chassis. Would the BMI chassis help reduce the chance of getting a chassis tweak in a crash?

Neil Rabara

The stiffer the chassis, the less it will tweak during a run. I would also add that when you put the chassis down on a flat surface that you have the batteries installed before you wrench down on the top deck. Alot of people will not have the batts installed, then after doing this tweak thing, put the batts in and tighten down the hold downs. After tightening them down, the chassis tweaks. So it's a good idea to untweak the chassis with the batts installed. I went to strapping tape vice the batt hold downs to prevent chassis tweak.

UnderDaHill

I've found that in most cases, when I crash, that I get a camber link messed up or something like that. I have never had the chassis tweak on me in a crash. I have always been able to find the cause without having to mess with the chassis.

I was just wondering if it is even possible to assemble the BMI chassis with any sort of tweak. I have never had this happen to me personaly and I've never made any effort to avoid it. My chassis always goes together with no tweak.

The things that HAVE tweaked my car in the past are as follows:
Most common to least common.
1) uneven droop or shock height setting(preload) left to right
2) tire size difference because I didn't rotate the tires
3) cracked stearing knuckle on one side (hard to see sometimes)
4) camber link shifted in hard hit
5) bad bearing on one side in hubs
6) putting the shocks together wrong (uneven length or rebound)

Hope that helps.

StewartFan20

iTrader: (4)

I have never tried to install the top deck with the batteries installed. I will try that this week. I also switched to strapping tape this past weekend. Still had tweek issues though.

Is the BMI chassis thicker that the stock chassis?

Neil Rabara

I'm not sure if Jason uses a thicker CF than the Pro4 stock chassis. I run an Xray and he uses 3mm CF which is thicker than the stock 2.5mm.

If you still had tweak issues with the car and you went to strapping tape and the batt thing, then more than likely you have torque steering issues, or binding problems.

StewartFan20

iTrader: (4)

I have taken the pinion off and the drive train is real free. I can accerate in a straight line. Under breaking is where I see the biggest difference. It will be loose on left turns and tight on right. The tires were brand new. I rebuilt my shocks in the last two weeks and was very careful to make sure they were the same length.

I am pretty sure it is the chassis because I can put one wheel on a scale and the other three on blocks and the left front is heavier the the right frount and the right rear is heavier that the left rear. I can undo the top deck and the weight is balanced from left to right.

Does any one know what the cost is for the BMI chassis? The website does not show the cost.

lazyboy

i have a stk pro4 and i ust got a tweak, but its no biggy, but has your car been on a four corner scale were the hole car is weight and shows you the weight on each wheel, my car had the same problem till i did that

just find a person at your track with four digital scales(make sure there good ones and not cheapies) and tweak out your car, my front right seemed to the be lightest on rubber tires so i add two of the 10oz. (dont quote me on that) sticky weights

hope that helps

lazy

protc3

iTrader: (13)

the pro 4 kit is 109.99 and comes with a 3mm chassis,3mm top deck,and 3mmk front and rear shock towers.the stock pro 4 kit is 2.5 mm carbon fiber that is what they call component grade.i use quasi isotropic which is layed at 0-90-45 degrees to increase torsional strength.component grade is layed at 0 and 90 degrees.i countersink all the holes a little past the tops of the heads to ensure that everything is pulled into location.sometimes you may aquire a minimal tweak if the molded plastic parts vary but usually the chassis pulls them into place.hope this helps

jason

ATLAS COPCO

Hello every one
We are very impressed with the BMI chassis. I have been sending pics around and a few people have asked me to get some prices together for them.
We are in the uk and we will be doing a race championship called carpet wars and by this thread thease chassis should do the job BUT we have a problem.BMI uk dose not reply to his e mails ,could we deal direct with you guys on the other side of the pond .We love the gold and the aqua chassis a real trick piece of kit
Thanks for your time
Simon
By the way it is for the xray

protc3

iTrader: (13)

hey buddy,thanks for considering my products.
i think ben at BMI UK is on vacation this week.i can cover for him until he gets back.just PM me what you need and i will take car of you.thanks again.

jason