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Is there any way to set end points for shift servo etc?

CoolRunning

Rock Crawler
Joined
Jan 3, 2017
Messages
521
Location
DownUnner
My shift servo was constantly buzzing and getting hot when shifted into high gear. It wasn't going to last long and I just realised it tonight after taking the body off. It was quite quiet but definitely wasn't happy.

I read there is no way to adjust end points for the shift and diff lock servos.

Is this correct?

I had to monkey around with the linkage and had to set it so I 'hoped' it would work but it was really a pretty crappy way of doing it. I had no precision and if you use a different servo brand, it simply might not work. I don't get any buzzing now, but it's not like I can precisely sort it if it happens again.

Is it that the TX isn't able to set end points for these channels or the RX?
 
I haven't seen a way of doing this through the Traxxas link app, its kind of devoid of fine tuning options. I only see end point adjustment for the steering servo using the transmitter not the app. have a look through this if you haven't already https://traxxas.com/sites/default/files/82056-4-OM-EN-R02.pdf

seems like the only way is to pull the servo horn off and reposition it, spin it to where it isn't straining anymore. The servo saver should allow some slop though so it must have been a notch or two off.
 
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There is a reason or recommendation for them on the Axials too but I set the end points and didn't use or need one for my Bomber.

Someone is going to come out with a bracket to get rid of the dinky little micro servos and put in waterproof minis with decent torque so I guess another TX with more channels will be required down the track to set them correctly which is disappointing. Though saying that I can easily repurpose it for our Yeti and control a 2 speed.
 
Mine was making a lot of noise as well. Went to drive it yesterday and would not move(spur was spinning but not the output shafts). Tore down the transmission and the "front" half was completely dry:no assembly lube or anything. I cleaned it and put WP grease on everything,reassembled, and it's working great with no noise.
 
I adjusted the actual link. My shift servo would buzz in high speed, shortened the link 1 turn. Now it doesn't make the noise and shifts between both gears just fine.
 
Mine do this sometimes, more so when they get all covered with dirt/dust. Removed body, blew off the dirt and they were quiet again, crawl awhile and making noise again. Think I need to shorten the link one turn at the ball end like Binaryterror did. :)
 
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I adjusted the actual link. My shift servo would buzz in high speed, shortened the link 1 turn. Now it doesn't make the noise and shifts between both gears just fine.

Adjusting the link as described is exactly what Traxxas customer service told me to do... right after they said if I want a steering servo that is strong enough for the TRX4 to turn the wheels while crawling and last more than 3 hours I'll have to buy one.

Still going to make them send me a stock replacement in the event I sell the truck I'll keep the upgrade servo i put in it.
 
mine was making a buzzing sound when shifted into high also, one turn to shorten the linkage did the trick, thanks guys for posting that tip, worked for me
 
Haha I'm not Farmer. Not sure if thats a compliment or jab..."thumbsup""thumbsup":mrgreen:

Hehehe, oops, fixed. :oops:"thumbsup"

mine was making a buzzing sound when shifted into high also, one turn to shorten the linkage did the trick, thanks guys for posting that tip, worked for me

Glad it fixed for you. "thumbsup"
 
There is a reason for the servo savers.

Yes, but not a good reason. It's likely to allow for factory tolerance, use of weak, sloppy servos, and a way around setting the proper endpoints in the first place (something that would need to be checked on each truck before it left the factory).

It would be easier to forgive traxxass for that, if they gave us a way to set our own end points. End points are computerized radio 101.

There is no reason some nice, torquey digital servos with properly set endpoints would ever need a servo saver in this setup. It's not like the shift or diff linkage would ever send a shock back to the servo, like a monster truck hitting a large bump or rock at speed. The servo simply needs to move a mechanical linkage from point A to point B, without deviation. Worst case would be a bit of load on them if the transmission needs to roll forward a tad to enable the gears to re seat

In fact, using the saver on my Ascender 2-speed made finding the proper shift end point maddening. It was much easier with a nice beefy digital servo, direct linkage, and a radio that takes itself seriously.


That all said, having taken my newly arrive TRX4 on a grand tour of the front yard, I'll add another notch on the "yup, the steering servo is the first to go" column. after my first run, it was actually a bit warm to the touch; first time I've ever had a servo feel warm before.
 
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