whynot

iTrader: (18)

Hello all, I was wondering how this car stays tweeked with out tweek screws, can someone please elaborate on this. I am thinking of getting rid of my crc and trying one of these out. I am no 12 scale guru by far and I find it a pain in the butt just trying to keep the chassie level side to side on it, have to shim under the front end to get it level is this common on all 12 scale cars or will this one be different and stay level. thanks

drover

Jason Hi
What about the new front end can you post some pictures?

InspGadgt

whynot: In modern 1/12th scale cars instead of adjusting tweak via tweak screws typically the car is balanced on balance pins so adjusting tweak is not necessary. Even with cars that have tweak screws they will usually set the chassis up on a flat board without wheels and tighten the tweak screws down until they just touch the chassis. Essentially setting 0 tweak...then they balance the car with scales or balance pins. It's all in the proper setup

20 SMOKE

iTrader: (103)

with this car you spend more time running it and less on working on it

protc3

iTrader: (13)

There is no need to mess with tweak on this car. The flex plates are mounted in a fixed position with precision machined spacers that will ensure that they are identicle heights. There is no messing around with this car for nonsense like setting the tweak of the pod. That is an age old adjustment that does not need to be. We are the only ones that have taken advantage of that. You will find the quality of our parts and fit and finish of our parts to be in a league of our own. We shoot for the highest quality to allow for easy assembly, and once you assemble it, you will see you have a very strong, precision race car. I hope to see you racing one of our cars in the near future.

whynot

iTrader: (18)

Thank you very much guys, I am very interested in getting one of these, Do the crc pro cuts have the right offset for this car? what tires do you guys run? and are they coming with the new bmi front end if not which front end does it come with? are the front lower arms machined to a tight tolerance so the chassey stays level and you dont have to shim it to get it level. sorry for all the questions. I just find it aggravating to have to go through all the measuring,shimming so the ride height will be the same left to right, but that just may come with racing 12 scales. my son and I both will prob. run this car in the fall, cant wait

20 SMOKE

iTrader: (103)

we run BSR tires you do get shim's for spacing the front end,and the front end is still the standard style front end with the shims

whynot

iTrader: (18)

thanks 20smoke, just to clarify I know that I will have to use the front end spacers to adjust ride height as my tires wear, what I am talking about is when I have the tires trued exactly and the the same spacers in I will also have to put .010 to .020 shims under one of the lower front arms so that the chassie will be level. I would usually have a difference of .5 to 1 mm difference. is there anywhere that sells these lower arms machined so I wont have to do this?
thanks
mike

chris moore

iTrader: (96)

This type of issue can come from many things. Improperly machined parts, improper setup, bent or missing screws, improperly balanced electronics on the car, etc.

InspGadgt

There are axle shims to adjust the rear width to the different off-set rims. The 3mm spacer sold separately is for the Jaco rims. I ran the CRC pro-cuts on the previous car at the Snowbirds race in 2009. As I recall I ended up only using 1 or 2 shims on either side of the axle.

The front end uses the standard older style AE dynamic strut front suspension but uses the IRS lower arms instead of the AE ones. The IRS ones are much more level so you won't have to go through the hassle of machining one arm to match the other. You will still have to shim the front end to set ride height and to compensate for tire wear though. BMI also makes machined spacers for the front end to set ride height that I really like a lot. They are a bit pricey for a whole set but well worth the cost I feel. The new front end will not be coming with the car but will be available as an aftermarket option. If you do not like the stock front end there are several options out there that work well. I am using the CRC front end and like it very much. There is also conversion mounts to use the new AE front suspension on the car. And Speed Merchant has an interesting front end but I'm not sure which specific version if any fits the screw spacing of the BMI. I tried to get one but had a hard time getting in touch with Speed Merchant and eventually just gave up.

20 SMOKE

iTrader: (103)

there is no problem with side to side ride height with the spacers like InspGadgt explained above

avs

iTrader: (2)

for the bmi rear axle, the crc wheels need less shim than the jaco. (note having no shims required is not good, because a reduced rear width is good if traction is low, if grip is up then max out the rear and adjust the front width as desired for balance)

i wonder if the front end height difference isn't really a tweak issue. if the tires are equal sized left-right, the weight is balanced left-right, and the front spring preload is equal, then the front ride height shoudl be equal left-right.

if the rear end is tweaked that would show up in the front ride height.
it could also be that the front springs have sagged unequally, you can measure and compare the free length of the springs to see that is the source of the ride height inequality. (note i have found the bmi springs preferable, they don't get sacked as quickly as other brands, primarily because they are an inherently better design, using fewer coils and higher strain levels. bmi must be using higher strength wire for their springs)

InspGadgt

I'm sure tweak will play a factor in that but the main issue was in the older style AE lower arms. Over time the molds have worn out pretty badly so that the left and right arms are not molded level in respect to each other. Some companies would get around this problem by machining the bottom of where the arm mounts so that they were level and would also give them more ride height adjustment to run the tires smaller.

avs

iTrader: (2)

oops, i had only used IRS or CRC arms and had never noticed any real difference.

whynot

iTrader: (18)

thanks jason and everyone else for your help. when will the new bmi front end be available? and what spares should I order along with the cars. am not sure how durable the flex plates are and if I need to have a bunch of these with the spacers in my box and are there different flex plates for tuning options