kewdawg

iTrader: (3)

The part number is different. The alumin. hexes for the touring cars, has #72036 as it's part number.

Paladin

Just setting up my new Pro4, am just about to order Delrin Outdrive sets for front and back.

I assume they are both the same part no: ?

fjm9898

iTrader: (11)

front and back? your not going to use a oneway?

Paladin

have used one-way, but front tends to understeer, someone suggested to try a spool, and see how that goes.

Have beenr acing for 3 months, and problem has persisted. Have tried setting up as default9as per build manual), and several other things, the back tends too stick ok, but have to bleed a lot of speed to negotiate corners, even at slow speed in backyard, the turning circle is horrendous. Have tried a new servo, setup the JR xs3, all trim etc.

Still turns like a battleship.

any ideas?

fjm9898

iTrader: (11)

try any of these, only do one change at a time, and if you still need more go to my next suggestion. 6 degree c-hubs, and 2.5 degree front pivot block. 2 degree camber front and rear. softer front spings. 1 degree tow out on the front, wheels look like \ / only not to eh that extreme, only one dgree or so. having the wheel like the that will help the inside tire pull the car through the coner more. if you do all that and still cant get teh thing to turn then i dont know what is wrong.

kewdawg

iTrader: (3)

Go over the front end of the car, CLOSELY. I bet you've overlooked something.

nordheim

iTrader: (6)

I have plenty of steering in my Pro 4 and I currently run the oneway. However, I still have huge issues with the tail end. It throws itself back and forth violently during driving. I am running the Hara setup from nationals last year. The only thing missing with my setup so far is the spool (which I have ordered). The car tends to spin as soon as I let go off the throttle. People seem to think this is all because of the oneway but I am also hearing people say good things about it.
I have turned down the brake on my ESC as much as I can as well as tinkered with the remote.
Have anyone else experienced something similar?

wagonman72

You have to dial ALOT of brake out when using a oneway. That may be part of the problem. As far as not turning in the back yard, if the rear diff is rough or too tight that can effect turning radius also.

floodo1

send me your setup and i'll check it out.

you cannot use any brake with oneway, this is why its banned from reedy race. you should never trigger to brake, and you should have zero drag brake (other than advanced drag braking technique).

also lack of rear traction is just that lack of rear traction. using a oneway vs a diff doesnt exactly effect rear traction...its changes FRONT handling, to which you adjust rear handling. a one-way is going to give you high turn in because your front wheels only have to steer, they dont have to exert any braking force.....so this moves the tire on the traction circle over to max steering traction. so the front suspension needs to be set with this in mind, then the rear suspension must be set so that both can work harmoniously.

obviously thats quite different than using a spool or diff where the front tires sacrifice turning traction for braking. but that doesnt mean you cant run a one way. im successfully running a one way against diffs at kingsburg which has some very tight corners. i think this is mainly due to having enuf rear traction.

sounds like your problem is lack of rear traction, the car isnt balanced, you have much much more front traction for turning and little rear traction to keep up. so try to up your rear traction and see if you can get too much. if you can do this then keep the oneway and lessen the rear traction till its balanced....if you cant make the car push with the oneway then you dont have enuf rear traction and you should switch to spool or diff.

thats what i say anyway.

aoizip

iTrader: (1)

double check and make sure your rear diff is not too lose...
if your rear diff is too lose, off power will make your back end unstable.
un-diff ..... I found this out the hard way of smacking into the wall..

floodo1

good point to check, but more than likely his problem is bigger than that. probably rear roll center and springs.

fjm9898

iTrader: (11)

i was also thinking it could be droop. if one side is off compared to the other of power then the weight shifts forward it will make the rear unstable. i had a problem like it before and mine was droop. basically with these little things so many things can go wrong.

the_barbarian

iTrader: (3)

I have a problem which I cant figure out

basically my Pro4 rolls quiet no noise almost at all in the drive train with no motor

when I have the motor in it sounds almost like the bevel gear is stripped now ive tried another motor and its making noise too

So im wondering if
1 the motor mound is slightly bent
2 the rear diff housing where the rear input shaft goes is worn making the spur gear move on an angle making the noise

when I have a crash I almost always break the spur gear now

when i hold a rev in the air it sounds kinda like the pinion and spur are moving close then apart constantly

fjm9898

iTrader: (11)

that rear input shaft might be bent. take it out and try rolling it around and see if you can see any wable in it.

loopedeloop

I would purchase the one peice alloy input shaft/spur mount.

It solved all my spur stripping problems, holds the gear much more stable.

The other thing i would check is that the rear diff mesh is not too tight.They are quite noisy when tight(well mine is)

And one last thing, dont overtighten the spur onto its mount. I have found that soft spurs like kawada brand can deform when overtightened making an in and out of mesh sound.