having troulbe on the straight

[Barnfind]

This isn't exactly an associated car but I didn't know where else to put this post. I have a bolink car that I am having trouble getting to go straight. Every time I hit the throttle it goes crazy and just sort of flips around and spins in circles. Why is this happening? I heard on here that I might need to put some thing on the rear tires to goet it to go straight but what do I put on them?

[Phin]

A silly question but have you installed a steering servo since taking that pic?

[Barnfind]

haha yes I actually did that today and then that's when I ran it and it was going crazy in the garage

[romulus22]

Loose diff and unbalanced chassis?

[Barnfind]

it could be an unbalanced chassis and for the diff I was messing with it all day and adjusting it tighter and looser but it never really made a big difference until it was really loose and the whole car would barely move

[jwscab]

you need to give us more information regarding the cells you are using, the esc, receiver, etc. If you had a steering servo on it and when you floor it, it flips out, it's likely the voltage is dropping too much causing the receiver to have a brownout resulting in erratic servo and esc behavior. might be poor connectors, old esc regulator, old cells, bad wiring to the motor, the motor could need a rebuild, or you might need a bulk cap on the receiver power input, usually called a stutter stopper.

[Incredible_Serious]

Could also be too much throttle, not enough traction in the rear, so it just lights them up. I had this happen with an old 10L in the street, would spin at 1/4 throttle. I found adding downforce by putting a body on helped (are you running with a body or naked?), as well as cautious use of the throttle. If it was for racing, I'd consider softer tyres and / or tyre additive (traction compound / 'goop')... but if it's just for blasting in the street, maybe not so much.

Alex

[Barnfind]

the battery I use is either a six or seven cell old NiCad battery. As for the motor I took it apart and cleaned it and replaced the brushes. The esc servo and receiver are just ones that I had laying around. and when I do hit the throttle the wheels stay straight its just the rear that is flipping around and spinning it out so I don't think it is erratic servo behavior. here are some pictures of the electronics.

[Barnfind]

Could also be too much throttle, not enough traction in the rear, so it just lights them up. I had this happen with an old 10L in the street, would spin at 1/4 throttle. I found adding downforce by putting a body on helped (are you running with a body or naked?), as well as cautious use of the throttle. If it was for racing, I'd consider softer tyres and / or tyre additive (traction compound / 'goop')... but if it's just for blasting in the street, maybe not so much.

Alex

I run it naked and I put softer foam tires on it but it still does the same thing. I don't have a body and don't know what kind to buy and what type of body would fit on it which is why I haven't gotten one yet.

[Incredible_Serious]

I run it naked and I put softer foam tires on it but it still does the same thing. I don't have a body and don't know what kind to buy and what type of body would fit on it which is why I haven't gotten one yet.

Bingo. We have a winner.

There's some 235mm bodies the Phin is currently selling in the BST now that would suit perfectly. Cheap too.... I'd buy one myself if I was living up there.

Alex

[Barnfind]

There's some 235mm bodies the Phin is currently selling in the BST now that would suit perfectly. Cheap too.... I'd buy one myself if I was living up there.

What if I don't have access to the BST section?? Are you sure it would fit this car?

Daniel

[Phin]

May have a buyer already for the bodies I'm selling but will let you know. You can apply for BST access since you have the required posts.

Pretty sure that Bolink car was a 9" track width at the rear but you should measure to make sure. RJ Speed and Wind Tunnel currently produce bodies from the old Bolink body molds that would be the most appropriate for your car. Here are the links:

http://www.rccarkings.net/bodies.htm
http://www.windtunnelracingproducts.com/index.php?cPath=42_27_33

[ChisaiKuso]

Having a body on the car or not having a body on the car is not going to make much difference when accelerating. The downforce provided by a body is only generated when the car is traveling at speed.

What sort of surface are you trying to run the car on? If it is unprepared asphalt your problem is simply a lack of traction. The fine dust/dirt that settles on streets and parking lots makes getting traction with foam tires nearly impossible. This is why race organizers spend so much time washing or blowing their track surfaces clean. Sometimes things like soda are even sprayed on the cleaned surface to make it sticky.

You can try using a tire traction compound on the rear tires only. It will help. You also do not want a tight differential setting when you are having traction issues. Keeping the diff loose (but not slipping under power) is your best bet. You are on the right track with switching to softer compound tires in the rear too.

A lengthy discussion on suspension tweaking and balance is something we can have at a later time. For the moment, however, do everything you can to soften the suspension in the rear of the car. This too will help with traction in the rear.

I hope this helps some, but keep in mind that it's only my $.02 based on years of oval racing at a sponsored level.

[THUNDERSTRIKE1]

check that the front suspension bar is level.Its been years but they use to put rubber under them and some guys tighten them down more to one side for oval racing or leaning the plate back for flat oval or carpet racing back in the day.If set for banked oval then thats the prob.don

[Incredible_Serious]

Having a body on the car or not having a body on the car is not going to make much difference when accelerating. The downforce provided by a body is only generated when the car is traveling at speed.

I hope this helps some, but keep in mind that it's only my $.02 based on years of oval racing at a sponsored level.

Sorry mate, I bow to your sponsored oval awesomeness. I based my ideas on my own hack running of a pan car in the street, in which I had exactly the same experiences with my inexperienced, heavy throttle fingered hands as Barnfind seemed to be explaining.

Alex