Losi JRX Pro Build

[matt1ptkn]

Wow. Looking great! I don't think I knew that MIP made dogbone outdrives for the LRM, very cool!

[jb7778]

Awesome stuff! Seen it asked but didn't see a response on the blue shock cartridges? Never seen them before....

[BattleTrak]

Awesome stuff! Seen it asked but didn't see a response on the blue shock cartridges? Never seen them before....

I hadn’t seen them before either but I just saw a set go through ebay.. they are MIP aluminum rebuildable units.

[Lavigna]

^ Yes, they are MIP aluminum shock cartridges. Quite hard to find. I am very excited that I was able to snag the 4 on ebay the other day. They do not appear often.

The car is a slider. Unfortunately the dogbones are a little too long, and they don't easily fit into the outdrives. These 2 problems I am going to have to fix if I want to use them. If anyone has solutions, I would love to hear them.

The RPM front bulkhead is the +10 degrees version. It puts the front forks back at a pretty steep angle. I was unsure at first, but the look is growing on me. I like it now.

[jwscab]

those yellowed ball cups sure do look like losi parts, the lxt time frame ones were hex and grey, but similar with the undercut by the ball.

mip=rebuildable cartridges

what isn't fitting on the bones/cups? if the bones are too long or short, it might be due to rpm rear hub, don't the losi original parts have two lower hinge pin options? losa-2038 and of course if the ball or pins are tight, it could be you need to sand the cups to make them smooth.

i just took a closer look and see the rpm parts do have both hinge pin locations.....did ya try em both?

[Lavigna]

^ Jswcab - I agree about the yellow ball cups. I think they are a Losi product.

The issue with the dogbones is 2 fold:

1 - The ball on the end of the dogbones (not the pins) is a little too wide to go into the outdrives. If I really force it, it will go in, but that just doesn't seem right, even for a shelfer. I like your idea of sanding the inside of the outdrives. I think I will give that a try.

2 - The dogbones are too long. I don't know where you saw the second set of holes, cause I only see one option on the RPM arms/hubs. I too assume the length discrepancy is because of the different dimensions of the RPM parts, but I would like to find a way to make them work. I think I have an idea on how to shorten the dogbones length. I will let you know if it works.

[jwscab]

The hubs have an upper and lower hole for the arm hinge pin. I'd try both positions.

How much longer do you think the bone is?

[Lavigna]

^ These hubs have only one hole.

If I were to push the dogbone all the way into the back of the outdrives, they are still a little too long to fit. Not way too long, but still too long, lol.

[jb7778]

Drooling.... The tower being swept back gives a more "modern" look/profile, its beautiful! LOL

The dogbone situation has my attention Ive got a set of those arms/hubs that I plan to use someday..... As mentioned I believe my hubs have 2 pin position heights curiosity will have me digging for mine this weekend!

[jwscab]

I guess what I see as a hole is just a filled spot in the molding then. the original parts had two holes, allowing you to drop the axle down. I think that was the default position.

another stupid question, you are placing the axle spacer ring on the outside of the hub right? if it was placed on axle before you put it into the hub, you will lose a few mm of bone space.

[Lavigna]

I have fixed my dogbone problem #1 drilling a new hole in the plastic connector. I did my best to shave and shape it to resemble the stock curve as best I could. You can see the modified piece next to the original below. It was surprisingly difficult drilling the holes in the exact right spot and direction on the rounded plastic. I don't have the benefit of a drill press.

The potential angle of the drives is limited by this modification, as the pin hits the edge sooner because it is now closer. This isn't a great concern for this shelfer though. Another small detail I changed was to file the metal roll pins holding the axles to the cross ball flat. It always bugs me how they stick out so far. It's a very small but pleasing change.

Dogbone problem #2 will hopefully get resolved tomorrow when I bore out the inside of the outdrives a little.

I also have an idea for the transmission case that meant I had to remove the whole rear end. More on that soon.

[Lavigna]

Getting close. This is my first JRX buggy build. I was looking at the transmission and realized the top mount on the transmission case is only needed for the truck. I very carefully removed the material. I like the clean look with the attachment gone. Thoughts?

I had an old, early no label JRX motor plate. It was bent and scratched. Unfortunately, I didn't take any pictures of it before I started working on it. I spent a LOT of time straightening in, then sanding and prepping it. I drilled the back holes to give it sort of a Litespeed look, and then painted it black. It's not as good as a Litespeed unit, but sort of looks the part at a glance.

I have a JG mini bumber coming.

[romulus22]

Enjoy the clean pictures, and great job on the car.

[jb7778]

Nice! Use to remove the mount tabs on my LXTs back in the day as well... Never able to get it so clean that you cant tell the mounts were ever there though!! What's the trick?

[Lavigna]

^ Thanks. The trick to cleanly removing the posts on top of the transmission are to be very very careful not to remove below the flat surface. I carefully grind it down as far as I dare with a grinder. Then I use an xacto to get it flat. Finally some light sanding and scuffing to match the texture.