When the TRX-4m was announced back in Sept after looking at the specs and watching the Traxxas videos I put one on preorder at my LHS. When it was released on Nov 11th I went up and picked mine up. While driving it around on the living room floor I noticed that at low speed the front wheels were catching when getting close to lock. Upon further investigation I discovered that the tires were rubbing on the steering linkage. So I fired up Freecad and designed some 1.2mm hex shims for the front wheels. Through them on the 3D printer and now my front tires don't rub the steering linkage.
When I took it out on my 1/24 scale rock course it drove pretty well but thought it need some more from weight bias. When I threw it on my balance scales it the bias was 49/51 so it could use some more front weight. When trying to climb one obstacles it would just sit there, giving it throttle and all of a sudden it would take off which made it a little unpredictable. Pretty sure that this is because out of the box it's a trail truck and not a crawler per say. I think the crawler gears will fix this but all the LHS around here are out of them. I heard on YT where putting a bearing kit in it got rid of the low end jerkiness and retained the wheel speed, haven't tried it so I can say for sure but it did look better in the video.
I swapped out the wheels and tires on mine didn't like the black rims on the red body. The wheels are Treal and the tire are Injora Crawl Masters.
I also did the driveshaft fix to help form losing the pin that is held in by an o-ring. I put a piece of clear heat shrink over it.
Not sure if it's going to help or not but I also designed and printed some high clearance links for the back. Seems to me that it exposes the driveshaft to more hangups but I might be wrong about that. On my indoor course it did seem to be better and I really didn't see the driveshaft getting hung up. This might be different outside on the rocks. Need some warm weather to try it.
When I took it out on my 1/24 scale rock course it drove pretty well but thought it need some more from weight bias. When I threw it on my balance scales it the bias was 49/51 so it could use some more front weight. When trying to climb one obstacles it would just sit there, giving it throttle and all of a sudden it would take off which made it a little unpredictable. Pretty sure that this is because out of the box it's a trail truck and not a crawler per say. I think the crawler gears will fix this but all the LHS around here are out of them. I heard on YT where putting a bearing kit in it got rid of the low end jerkiness and retained the wheel speed, haven't tried it so I can say for sure but it did look better in the video.
I swapped out the wheels and tires on mine didn't like the black rims on the red body. The wheels are Treal and the tire are Injora Crawl Masters.
I also did the driveshaft fix to help form losing the pin that is held in by an o-ring. I put a piece of clear heat shrink over it.
Not sure if it's going to help or not but I also designed and printed some high clearance links for the back. Seems to me that it exposes the driveshaft to more hangups but I might be wrong about that. On my indoor course it did seem to be better and I really didn't see the driveshaft getting hung up. This might be different outside on the rocks. Need some warm weather to try it.
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