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steveconn
29-01-2018, 06:59 AM
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
29-01-2018, 05:34 PM
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
29-01-2018, 06:47 PM
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
29-01-2018, 08:15 PM
What's a power cap?

steve-thebabystore
29-01-2018, 08:43 PM
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
29-01-2018, 10:43 PM
No expert but assume is the type mentioned on this page

http://www.reedypower.com/products/reedy_speed_controls/brushless_competition/

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

danielc3009
30-01-2018, 07:33 AM
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.php?product_id=414468&gclid=CjwKCAiAqbvTBRAPEiwANEkyCAP_WUqZeagFkh1J-rQUKhHtSHnzgF8gy7kPkqHqvg6Gdz_sb6jC3hoCbi4QAvD_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

steveconn
30-01-2018, 08:37 AM
Sorry, when you said cap I didn't understand that you meant capacitor. The reventon R does have a separate capacitor on it, this is soldered in not on a connector.
Does it sound like mine has failed? If I replaced it would i need any specific spec?
Thanks!

mattr
30-01-2018, 01:26 PM
TBH, i've had the brake issue on both of my reventon ESCs.
It also came back after one of them had been left for a few months.

Only way i've found of fixing it is to basically reset to factory and update the firmware. Or use a different firmware.

Unfortunately, this isn't likely to work for much longer as speed passion seem to have stopped trading (at least, there is no website.....)

mattr
30-01-2018, 01:29 PM
Thought Petitrc have this, which i am going to try tonight!

http://site.petitrc.com/reglages/speedpassion/reventon/ReventonPro_InstallMuchMoreSoftware/eng/

Ah, shitbags, none of the files/links are there, and some of them appear to have disappeared permanently.

danielc3009
01-02-2018, 07:27 AM
Sorry, when you said cap I didn't understand that you meant capacitor. The reventon R does have a separate capacitor on it, this is soldered in not on a connector.
Does it sound like mine has failed? If I replaced it would i need any specific spec?
Thanks!

I don't mean the capacitor on the esc, I mean you should try adding one to the receiver to help regulate the receiver voltage

steveconn
01-02-2018, 09:16 AM
Ill give that a try mate. which port should I plug it into? A spare servo one?
Thanks

Zipper
02-02-2018, 01:39 PM
Ill give that a try mate. which port should I plug it into? A spare servo one?
Thanks

Any spare one on the receiver is fine.