HXRC 5ive-T Build Log

[HXRC]

The day she arrived at her new home for 620usd delivered, needed a new front bumper, a rear hub, a carb clean, and some maintenance.

That didn't stop me from getting creative to take it for a test drive!

Got it ripping, but needed more power and the clutch was slipping.

Oh I see, classic CY. At this point I ordered a cheap head kit off ebay, but it still ran and the head was off. So I did some mild porting which I didn't picture. Then made a base gasket out of a sheet of paper and an aluminum can coated in copper spray, paper on the crank case side al can on the cylinder side. This of course set my squish way too tight. Since I had another top end on the way I went at the piston with a flap wheel. In hindsight I should have gotten more precise and milled the piston. Because this is the top end they sent me, top stock, bottom the ebay junk.

Squish on the shaved piston ended up being 0.45mm on the intake, 0.55mm transfers, and 0.65mm on the exhaust.
This mod noticeably bumped compression and performance! For a junk top end I was pleased, but still needed a pipe.
I also needed a killswitch, bigger battery, and a clutch.

Can't stuff much more in that box. Still could use a better battery, this is made from old drill 18650s 2s3p. I also installed a cheap ebay 8k clutch backwards (intentionally). This really helped my clutch response! I also needed to tune the diffs, put 500k in the center, 60k front, and 100k rear.

This is where things got interesting. I really wanted a silenced olimat, but didn't like the wait or the price. Plus I like building exhausts, had some spare pipe and time. Did some maths and metal fab, with the tube I had came up with this:

Tack welded all together ready for finish welding and work.





Total cost: $40
Video of it in action here:

https://www.reddit.com/r/rccars/comments/113g1p6

At this point in the build I was pleased, but the saggy suspension needed addressed, I busted the front bumper again, the rear cage to bumper pin as well, and the body was getting trashed. So I made a large DDM and Detroit order. But forgot new shock boots....

One man's old dish glove is another's shock boot! 40w 13.5lb front 50w 11lb rear
Designed and printed some new parts.




Then I waited for my Detroit order to arrive, and made a prototype center brace

 

[Rep732]

Welcome... I applaud your enthusiasm but I do hope you get a tuned pipe for that thing.

 

[HXRC]

Welcome... I applaud your enthusiasm but I do hope you get a tuned pipe for that thing.

Thanks! Happy to be here

I mean, my pipe, while it's not the best, is technically a tuned length. I figure it's better than a rovan pipe and I really like the rear dump. I might eventually get a tuned pipe, but a filter and velocity stack definitely made a notable difference as well. I feel like my money would be better invested in a bigger engine.

More updates and pictures shortly!

 

[Rep732]

 

[HXRC]

Here's the approximate tuning on my pipe so ya'll know I'm not BSing you when I say I did some math to tune it.

My Detroit order finally arrived right as I was about to call them and ream them out for never shipping it. (I never got tracking).
So I chilled out and got painting and building. Hindsight I wish I'd used a vinyl, but at least the paint is easy to touch up. I also got FLM braces, a DDM top plate, a 1" velocity stack, a DT1 dome, and brake pad springs. The brake pad springs were too small. So I cut down some SCX24 shock springs.

I also printed some mud flaps out of TPU

Then I got my SendCutSend order! CF and 7075

Time to get drilling and tapping! 2.8mm +/-0.1mm inward from the front face, 42mm of separation.

I filled these voids with JBweld, if I didn't have an overkill drill press and some patience I would have done it before drilling.

Don't mind my extra punch marks!

Then I cut down a 309mm arrma felony center brace. I've since replaced the M4 bolts with M5


Sorry for the potatoe quality picture here...

 

[Clubin]

Nice work.

 

[John Parks]

Good job, liking the body

 

[HXRC]

Took the family to the park to let 'er eat. Success?

 

[Rep732]

Atleast you had a good time I take it. Must of been a good hit to rip that hinge pin out.

 

[HXRC]

Absolutely! That was the first time I've really gotten to open her up and hear her whole song. This pipe is female dog'n!
I was flat out, caught a bump or something wrong and did a pretty aggressive cartwheel on to that side.

Edit: lol at the forum censorship

 

[Seandonato73]

It's is a "family" forum so need to keep it pg 13....

 

[HXRC]

I've put a couple of gallons through the 5ive since my last post. Thought the engine gave up the goat for a minute, but it just needed a new carb. However, it still only has 100psi wet and cold. Just saving up for an OBR reed while waiting for the CY to blow.
I was having some electrical/failsafe issues, so I redid all of the wiring and installed a huge, overkill, switch. My old spektrum servo also died, so I'm in the market for a nice affordable servo as well. Running a cheap JX for now. Might get a PowerHD, but thinking I should save for the AGFRC. Also printed a throttle servo brace.

I went to a Mountain Bike park and found a pile of bricks outside of my line of sight.

Sheared the hinge pin and bent the plate, shock appears to be straight luckily.

Luckily I had some spare hinge pins and a full set of arms on hand. Ripped a screw out of the bulkhead, so I had to use a longer screw and some glue.

I'm digging the red arms, I need to install them in the back now too.

 

[HXRC]

I'm well over due for my annual update! I started racing with a local Facebook group, and everything snow balled.



I built a reed ported a rovan 45cc, she ripped pretty well for ~5gal, before I had a minor ring land failure causing high case pressure. I assume due to my mistakes in repining the piston. At it's prime the 45cc ran 46mph with 54/23. I plan to rebuild it, but I've been playing around with other engine builds. I've built a 49, a 50, a 43, and a 56.



I've also "built" 2 new stainless pipes from RC pipes instead of completely from scratch. The scratch built pipe worked well, but the header eventually suffered fatigue cracking from being mild steel.

Here's the 49cc with a modified conquer exhaust, the side bleed stinger was eventually cut down to 3" and then made into a dual bleed.

This pipe is a ripper for sure, but I wanted something bigger/longer for the 56cc.


Of course to support this extra power I've upgraded and shimmed the whole drivetrain.

There's the just of what I've been up to with the 5ive, I'll try to fill in the rest of the build soon and keep it more up to date. A lot more pictures and a couple other builds to post.