DuckStang

iTrader: (14)

Have you guys ever had this happen??? Car ran good for 3 qualifiers, then in the b-main it just would not handle at all. Nothing has been done differently in between rounds. I cleaned and Paragonned the tires the same way I did, temp did not change, etc. Basically I just checked ride height but not change it, cleaned the tires and Paragoned them. Car would just come around on me when I was easing off the throttle or getting back into it. Not slightly, it was violent.

I run a Jrx-s type r. I can post the setup if it is needed.

sosidge

It's happened to me plenty of times.

Normally when you give the car a good going over afterwards you'll realise that it took a tweak, the tyres came unglued, or that a part failed or got bound up.

The other possibility is that something about your tyre prep routine made tyres that worked well after one applications work terribly after several. Perhaps you are using too much and too often.

DuckStang

iTrader: (14)

I think that's what it is. Cleaning tires too much and using paragon before each run. I clean the tires after every run and paragon themalso. You think it's too much??? I also checked for binding, there was none. I went over the car with a fine comb and I just can not pin point what went wrong. Only thing I have not checked is the diffs.

rccartips

iTrader: (3)

Maybe track grip went up.

pejota

iTrader: (12)

Check your wheels for cracks or warpage. I had a similarly erratic problem. After two complete rebuilds i happened to blip the throttle while it was on a stand and the whole car vibrated so bad it rotated the whole stand counterclockwise.

fox88gt

iTrader: (5)

+1 on whats been said already, all very good points and good things to check. What class are you running? I've had it happen to me, most notably in VTA, after a while the tires will "let go" and a new set is the cure.

wingracer

iTrader: (24)

Most common cause, a tire problem of some sort.

Next, a broken or worn part of some kind or a tweak issue. Move this up to number one if you're bouncing off the walls a lot. Also, a blown shock could be the problem.

Next, diff issue. Make sure one hasn't loosened up on you or something.

Next, major change in the track's grip level.

jake95

iTrader: (27)

most likely tweak maybe diff came lose

BOG

iTrader: (47)

at my track a lot of use run jrxs r's and i usually before a race loosen up all the screws in the center that hold the center plate down from the bottom and the top and tighten them all down from the center. sometimes after hitting a way the chassis will tweak and this brings it back to flat!!

DuckStang

iTrader: (14)

That's what's bothering me, I was not making love to the wall the three rounds before. I do not think I even sniffed it, the car was that good. I took some advice from this thread and placed the chassis on a flat surface and it's not tweaked. I even took a mechanic's straight edge, the one i check cylinder head warpage with, and the chassis is very flat....

I am about to tear into the diffs later on today. See what I find and post it in here later.

MikeXray

iTrader: (73)

Check your diffs for sure, and check your chubs, they tend to crack and not break, or lose the bottom screw, etc.

bad_b4

iTrader: (43)

if the car was "that good" as you claimed it was before,then why were you in the "B" Main?

Just messin with ya...but yeah,id check all the above mentioned,there is a ton of knowledge here...sad thing is,it will be a $1 part...LOL

Andy Z

iTrader: (9)

I'd check the following:

-Tweak (as in put it on a tweak board make sure the bubble is in the center, if not then adjust the springs on the opposite side of the level to make it center)

-Diffs: make sure the rear diff isn't too loose (also check to make sure its smooth)

-CVD Pins: make sure none of them are hanging out a bit

-Body: make sure its not dragging or touching a wheel

-Droop: Just re check it

-Camber: Just re check it

ark

iTrader: (11)

+1 for diff. Most of the time when the car seems off it is the diff even if it feels ok by hand.

DuckStang

iTrader: (14)

Ark, you were right, it was t he diff. Took it out, re-cleaned it and sanded the plates. Now it works like a charm and the car was dialed. Ran into another problem.

When I accelerate, the car torques/veers to the right.....half way down the straight, it goes straight....i tried to trim it our upon the start of the straight and it does go straight, but at the end of the straight it pulls left....ALOT.....could this be one of my shocks???