Problem with speedo, help?

steveconn · #1 29-01-2018

I'm new (again) to R/C cars after a 25 year break.
Raced for the first time last night with my K2 and everything second hand and had a issue that no one at the club could fix. I'm running a Speed Passion Reventon R speedo and it seems to have a problem, it work perfect 90% of the time but every now and then the brake doesn't work, happened twice at the end of the straight and smashed my wishbones each time. Tried changing everything possible with the program card but still happening. It seams to be if I come off the power and let it roll a few yards before I brake, if i come straight off the power and brake it works???
Using Sanwa Exzes X radio but I'm sure its fine as all settings standard.
Any help appreciated...

danielc3009 · #2 29-01-2018

Hi

Try fitting a power cap to the receiver. I had the same issue with the speed passion reventon esc but it didn't do it after fitting a power cap

longman · #3 29-01-2018

My reventon pro is the same and also my mates pro does the same. We have both tryed updating the firmware but it's still the same. Power to neutral then brake = no brakes...
Power to brakes works every time..

steveconn · #4 29-01-2018

What's a power cap?

steve-thebabystore · #5 29-01-2018

A capacitor that helps smooth the power to the esc and stop sudden changes in power supply. Probably a simplified response but can understand how it helps. Several top end esc’s have external capacitors for this reason.

daz75 · #6 29-01-2018

No expert but assume is the type mentioned on this page

http://www.reedypower.com/products/r...s_competition/

Not sure if they are all generic or you need specific ones

danielc3009 · #7 30-01-2018

Quote:

Originally Posted by steve-thebabystore

A capacitor that helps smooth the power to the esc and stop sudden changes in power supply. Probably a simplified response but can understand how it helps. Several top end esc’s have external capacitors for this reason.

All esc have capacitors on them but they are built into the casing on some escs

A power cap is a capacitor that plugs into a spare socket in the receiver and helps maintain a constant voltage to the receiver and servo.

There is lots of different brands available and the prices vary a lot, here's a link to a savox power cap
https://www.modelsport.co.uk/index.p...hoCbi4QAvD_BwE

I've not had any experience with sanwa Radio but I run spektrum receivers which are prone to "brown outs" (going into failsafe is the voltage supply drops) and a power cap helps prevents this