IRC Racing Photon

[BrianG]

It might technically be 16th scale, but it seems short to me. The buggy shell in general kinda looks squished front-to-back vs the way 8th scale buggies look. And if that's not bad enough, the touring car conversion makes it more obvious.

[squeeforever]

Brian, you are never satisfied, are you? :p I would check into the center diff out of the Kyoshos Inferno series.

[BrianG]

lol, never! What's the sense in spending so much money on this hobby if it's not perfect? :)

Actually, I kinda like the "squished look". Makes it look sturdier somehow.

That's a good idea (about the CD) - I might just check into that. I want to see how it handles as-is first during actual track use.

[BrianG]

OK, I had some more time to really look into it and run it.

Pros

• It's fast
• It's RTR complete with motor, ESC, radio, lipos. You have to supply the 8 AA's for the transmitter.
• Brand name ESC (Mamba 25) and motor (Himax).
• No radio signal glitching.

Cons/Observations

• No center diff.
• Internal front/rear diff gears are plastic. Haven't confirmed this, but that's what the manual said. Maybe that's actually OK for something this size, I dunno.
• IMO, layout needs to be changed because the steering servo screw is VERY close to the lipo pack and there's potential for a puncture. So, I swapped around the bellcrank and servo to the other side. Plenty of wiggle room for the lipo pack now, but the ESC and receiver have to be relocated as well since the servo arm and linkage are in the way of the stock locations. ESC was relocated to the top plate.
• ESC gets quite warm, ~150*F after a few minutes. Maybe it's the relatively hot motor (5300 kv) running at 3s with a small ESC. So, I added a heatsink to the FETs and re-heatshrinked ala BK Warrior style. Still gets warm (~130) but better. Probably runs better when not doing so much partial load running, but can't verify this since the thing is too fast for the basement. :)
• The pinion came loose so I had to grind a slight flat spot on the shaft. I also Lock-Tite'd it just as an extra precaution. The set screw was a PITA to loosen and re-tighten. It feels like the set screw threads in the pinion aren't cut right or something.
• The radio is hard to calibrate to the ESC. Throttle has to be reversed and the trim has to be set biased 3/4 the way torwards the reverse direction in order for the ESC to recognize reverse.
• There's something up with the front diff. When running in the air, one side tends to turn faster than the other, but it seems to run fine on the ground.
• ESC tends to pulse when running slow. Not cogging, but the buggy moves about a foot, stops, moves another foot, etc. It's definitely meant for high speed running. Smooth operation from about 5mph+.
• The radio charging jack does not work with a standard peak detection charger. There's a circuit in the radio that keeps the charger from reading the voltage level of the batts, so it's meant to charge using a simple "wall-wart". I modded the radio so the jack is wired directly to the batteries and now fits RadioShack size "N" (IIRC) power jack, which is what I use in my Spektrum. Charging is now possible with any deak-detection charger.
• ESC and lipo pack come with Tamiya connectors. Worked OK, but swapped over to Deans anyway.

So, is this thing worth the $239 pricetag? I personally don't think so, but I have exacting standards so I'm not sure. I guess I expected something closer to the quality of an 1/8th scale, just smaller. This isn't it.

I don't see this as being something I'll be running a lot and will most likely sit on the shelf collecting dust. :sigh: Anyone want a good deal on a slightly used (and somewhat improved) Photon?

[squeeforever]

What we talking Brian? :)

[BrianG]

I'm ready to take a loss. What do you think is fair?

[BrianG]

Well, I found a guy at work to take the Photon off my hands. I took a bit of a loss, but now he's hooked into BL. He can't believe how much power that tiny motor had! He took it outside and test-drove it and then grabbed me to go to the LHS to get a real charger, another battery, balancer, etc. Like a kid in a candy store. :)

He does have a little to learn about driving though. He was driving it in the parking lot at work towards him, turned a little the wrong way, hit the throttle instead of the brake and slammed into a brick wall at WOT. OUCH! Surprisingly, all be broke was the lower arm hinge pin retainers. Oh, he also dented the brand new ThunderPower 3s pack he literally just bought.

The lipo the truck came with is a little undersized IMO. He ran it until the ESC cut off and then hooked it to the balancer and it only recognized two of the cells. He freaked out a little. So, I measured all the cells and one of them was at 2.7v, but the rest were at ~3.5v. I put it on a slow 0.3A charge until the low cell came up and it charged fine the rest of the way. Time will tell if it was just an isolated incident. The extra Thunderpower pack (3s 2.1Ah) he got runs fine though.