Darkstar's U4RC Tuber Build

[darkstar]

One of the last few updates we have here. This one is a big one!

I decided to re-do the RX panel, and extend the bottom section downwards... in order to make it look like a firewall. (don't mind the extra holes, they will be covered by a wrap)

Also decided to throw an X in the hood, to help with keeping the hood stable and rigid, and tossed a nice coat of flat black on it. I also used a body post from a mini Losi to help keep the back end of the hood down, and to help keep the interior in place.

Also did a little testing on the electronics to make sure there are no binding issues & that the steering still gives full throw.

For the interior, I went with the HP mini trophy interior. Had to do a little trimming on the interior but that is to be expected.

Here we have the almost finished product. All the panels bolted up and interior in... all without the wheels.

Here we have everything ready to go. Full roller (minus the wrap).

And the typical flex shots... the 2 pieces it's sitting on are 2" tall, and a 1/8" thick bushing.

That's it for now! I'm just waiting for my wrap to be finished up and sent, so I can finish that off. I also need to get a hold of a spare tire so I can really finish it off.

This weekend I will be doing some testing / suspension tuning at our next U4RC race in Cherry Valley, CA!

 

[Rockpiledriver]

Looks great Jeff!

 

[n3cron99]

That looks sick! Great job

 

[PSW]

Sweet build, Rims look hot!

 

[Szczerba]

Love the look, great work.

 

[mikl]

Looks great. I am looking to get those tires and wheels but in red. What foams did you use?

 

[darkstar]

Looks great. I am looking to get those tires and wheels but in red. What foams did you use?

CI Double Deuce 5.5 foams. No cut

 

[darkstar]

Spare tire update!

Finally got a spare tire to put on the back of the rig. Thanks to my buddy KRAWLR4life.

I had to drill out a hex nut just a tad to get it to clear over the tire mount. Once that was done I used a few washers to get it to sit even and bolted it up.

I didn't get a picture of the suspension at full bump, but the swaybar does not hit the tire at all. "thumbsup"

I also had to drill a hole in the hood, for our transponders, and now that is setup and ready to go!

Still waiting for my wrap to come in, so I can apply that and get it setup and ready for some U4RC racing.

 

[WesTX]

Just an FYI, that trailing arm bolt being in single shear on the outside will probably lead to some bent screws at some point. I have had the issue on my MZ u4 chassis recently, bent 2 and now I am working on taking some rectangle tubing to create a double shear mount.

Looks really good, ready to see it with the wrap on it.

Wes

 

[darkstar]

Just an FYI, that trailing arm bolt being in single shear on the outside will probably lead to some bent screws at some point. I have had the issue on my MZ u4 chassis recently, bent 2 and now I am working on taking some rectangle tubing to create a double shear mount.

Looks really good, ready to see it with the wrap on it.

Wes

hmm.. good to know. I'd like to see your fix when you have it.

 

[Revoasian]

That is one sweeeeeet lookin rig. Nice work there man. "thumbsup"

 

[darkstar]

Kinda a larger update here...

The shake down run went great... I had a few small issues to deal with, but not a deal breaker.

I was running soft springs in the rear all around. Changed the main spring to a more firm spring, and left the upper spring the same which was a firm pre-load spring.

I was running 45wt oil in the rear, 25wt in the front. I plan on changing the oil to 15wt all around, and see how it responds at our next race (May 3).

I plan to move up a tooth or 2 on the pinion, to a 15 or 16. Our next race at Glen Helen is a larger track, so a little more wheel speed isn't a bad thing.

Finally got the Carbon Fiber wrap, from one of U4RC sponsors RC Paint Masks Vinyl Decals

This CF vinyl is beyond badass, looks very real and was not hard to apply at all.

Added a little CF vinyl to the shock mounting plate, to give it a nice little look to it.

Up next will be adding the extra stickers to the panels, and final mounting on the trophy rig and then beat the crap out of it at our next race!

 

[Thechewmaster]

WOW! very nice "thumbsup"

 

[darkstar]

Another update before the race.

Changed out shock oil to 15wt in the rear, 10wt in the front. Suspension cycles much better now.

Also got the panels stickered up.

Up next will be doing final mounting and get it ready to beat the crap out of it!

 

[darkstar]

Finally got all the panels mounted up and it looks great.

I also had to change the servo out, due to cracking my Savox case and the gears making some noise I don't like.

Ended up going with a MKS DS1220. This servo is super smooth, fast and has great power, even at 6v, but it can easily handle 7.4.

Car handled great, Glen Helen U4RC Track was super dry, so I had some traction issues, but that comes with racing.

I did have some issues, I broke the rear tire carrier yesterday but thats a none issue honestly.

Also smoked the Tekin Pro4 3300kv motor, not sure why though but since I got it in trade, I believe it was already on it's way out. I had no binding issues, gearing hasn't changed.

I will be calling Tekin to see what my options are.

On to the pics!

 

[THAT1GUYETHAN]

This is one of the nicest builds i have seen. I thought U4 vehicles had to have a arm suspension up front? (newb-ish kind of question, sorry). Either way, looks pretty damn dialed.

 

[darkstar]

This is one of the nicest builds i have seen. I thought U4 vehicles had to have a arm suspension up front? (newb-ish kind of question, sorry). Either way, looks pretty damn dialed.

Thanks boss "thumbsup"

No, U4 class rigs.. depending on what class you run, can have A Arm (IFS) or Solid Axle up front.

 

[darkstar]

Small update here...

After smoking the Tekin Pro4 3300kv.. I send Ty Campbell a message via Facebook, he told me he would look at it when I sent it, and let me know what my options are.

After Tekin received the motor, and talking with their service department, Tekin decided to issue me a warranty replacement and sent me a new motor. Hand down to Tekin for what they did for me... after all, the motor was not new to me, and I don't know how old it was when I received it... they could have very well told me they wouldn't do anything...

After busting off the rear tire carrier, and seeing the rear sway bar exposed a bit, I decided to change it up a little.

I ended up moving the sway bar more inward, and having it mount to the trailing arms, as opposed to the rear axle.

As you can see, I had to drill 2 holes opposite sides of the chassis. I got very close to making them identical, it's only off by 1-2mm.

Even at full bump, the sway bar clears the upper part of the chassis by about 5mm on each side and also does not hit the shocks at all.

Hoping to get everything else mounted up and do a little testing.