I was practising and setting up car at Moorebank today and your friend with his electric grey Serpent 1/8 was there too.. ... very fast car and sooo quite

 

Looks cool mate! I would be interested in seeing some footage of this!

Where do you get the CF sheet from?

Is that battery near the spur gear going to be safe?

What body will be going on?

 

Bloody RC Teaser. Lol.

 

Duddy, yeh Martin told me he would be there. apparently it wasn't going as fast as normal today.

to answer a couple of the questions.
I've got a couple of lola bodies for it and although the batteries are close to the spur gear it will be sorted once the straps are in place. from the testing my mate has done it handles best with the batteries positioned as far back as possible so getting close to the spur is a necessity.

the cf sheet can be bought from hong kong through 3 racing. top quality high stiffness cf.

 

A bit further along now. Just gotta install the two speed pinion adapter which my mate bought for me and servos then program speedy.... oh nearly forgot I have to change my battery connector for 6.5mm bullet connectors. Great more fun with the soldering iron....

here's the last few pics. I did the paint last night. Started it at midnight. Lol. Just doesnt seem to be enough hours in the day. It's a little rough up close, stickers I made on the laserjet and lamineted with one side of the stick-on clear laminating pouches. Came out quite nice. Pinstripe is a little rough due to the dodgy tape I used but the shell is not expected to last long so I don't really care too much. The overall effect of the classic retro GULF oil livery is pretty cool I think.

 

cool looking weapon .. those red plugs though are soft tho, youll need to sort those out. Plenty of the kids up the track have shown them to me splitting. They dont like heat imo

the goal is to beat Martin..

 

yes i agree those red plugs look way inderrated for any serious amps. I was very surprised that they came with the batteries when these batteries supposedly can push out 45-90c. not exactly confidence inspiring for battery quality control. As I've mentioned before I have low expectations of the Turnigy batteries so I don't get too dissapointed. I would be more confident if they just supplied them with no plugs because those red plugs are a liability which they should already know. I wont be taking a chances so i will be using Castle 6.5mm bullet connectors.

 

it breathes.

3.30 am. jeez I need to get a life.

man that was hard work. I'm wrecked.

martin is a dude. stayed with me till it fired up. i'd be still workin on it if it weren't for him. his missus is gonna kill him. worth at least a case in the beer economy I reckon.

 

Top job paolo man that is persistence.

 

yeah those finicky little setup jobs just kept growing and took all night. it's not the sort of car to drive without a perfect setup. heading down to moorebank later today to give it it's maiden run and fine tune the chassis.

 

3.30am .... Lol
And I felt guilty leaving at 11.30pm .... It is an exceptional piece of equipment, I hope today is rewarding for you bro .. Lol
Pictures please, tell Martin to video it


Sent from my iPhone using Tapatalk

 

I noticed it does'nt have a pinion on the motor, that would effect handling. He He!
Nice looking piece of work, dito on a video.

 

that's one of them brand new zero tooth pinions. lol. first lap of the track and the heavens opened up. wasn't meant to be eh!

 

oh yes it lives alright!

took it out to Whalan reserve this arvi and punched out two batteries. whoa it's a handful.

I had a little I.D. 10. T problem though. in an effort to smooth out the twitchy acceleration and steering I adjusted the exponential and kept doing so with no improvement, infact it went worse. I was actually adjusting it in the positive direction instead of the negative. The extremely punchy throttle eventually made the one way bearing slip in the flange carrier. I dare say if I weren't such and idiot the one way would have held together and I would had a heap more fun. it was like the throttle and steering were just switches. I'm usually pretty good with settings and radios so all I can put it down to is the fact that I was recently setting up a spektrum radio on my mates brushless 1/5 truck and those spekkies all backward so I probably just carried over the backward logic of that heap'o'crap spektrum onto my nomadio. fkn lame excuse I know but it's true, those spekkies make your brain soft. lol.

 

the batteries performed to expected?

 

yep they gave good supply without fading. they got warm and swelled just a tad. but mind you I dumped them real quickly in about 8 minutes down to 3.4v per cell. I am not concerned with the amount of swelling the pack showed. it was very minor which I see all the time in my buggy batteries. i'll let you know more as I put a few more charges through them and set my Exponential correctly. the way I had it set up the system would have been spiking current pretty bad because the throttle came on way too quick with my reversed expo adjustment mistake. I will try to run it again throughout the week and set it up for smoother power delivery. the batteries and speedy will like that. so will my heart rate.

 

here's a little video we took today. it's only the second battery I've put through it here at moorebank and handling needs a little sorting but damn it's fun. Martin and I ended up doing over ten batteries today. was charging the turnigy nanotech lipos at 10amps. I have three sets and never once had to wait for a battery to come off the charger. all I can say is ....,,, awesome.

 

man .. thats fly'n!
what sort of wheels are you using?
I can see once you have some racing lines sus'd, youll be shredding the competition.

its a good feeling to be able to charge at a high amperage ey.. makes it all worthwhile on the day

 

Certainly felt quick. The Nanotechs are rated at 10c charge so thats about 33amps max with the capacity I was using. I don't know of a charger that can do 33amps but my iCharger106b goes to 10amp and its good to be able to use it on 10 amp quickcharge with the balance leads plugged in. That charge setting cuts the balancing process short by stopping the charge around 95%. Probably only took 15-20minutes per charge It's actually cheaper to spend a little extra on high charge rated batteries cause you don't need to own so many. I could of got away only having two sets but with three sets of batteries it gave a rest/cooling down period each time I used them.

Handling was way off in that video as you noticed me struggling to keep the car on the race line. Steering input was far too sensitive after disconnecting the front sway bar. When it was connected the car was understeering like a dump truck so I disconnected it as a short term solution so I could get around the sweeper without ending up in the fence. I actually crashed a few times that day due to the steering either understeering with the sway bar or oversteering and wandering at speed without the sway bar. I have a lot to do in that area because I got a car that was setup for an entirely different track and the brushless conversion adds about 500-600 grams so chassis tune is way off. It's gonna be a steep learning curve with a few more trips onto the grass I think but once I get the chassis tuned its gonna be an absolute weapon. The acceleration is just phenomenal. There is a tonne of reserve power at any time. You blip full throttle up the straight and occassionally out of a corner but its only for a split second. You can't blink or have a lapse in concentration cause it'll be all over before you can say... too late you can't even think about saying anything.

I know now why they sell these lexan body shells in 3 packs, LOL. Mine looks like a wrinkled pair of linen trousers now. gotta start painting the spare one.

BTW, wheels are pretty mch all the same with slightly different offsets for different brand cars and tyres are generic foam tyres pre-glued. Bought From Twister hobbies. 37shore front and 40shore rear. We started out on 35f,37r but as it got hotter we got better traction from the harder tyres.

 

The new icharger 1000w will do up to 30a
Mine does 30a.. its either 15 per channel or 30 in one, depending on how many you charge at once.

half a kilo is a fair whack of extra weight.. I spose as you said though, tune it out more & it probably wont matter, youll still be flying past the nugget nitro's

 

That may very well be my next charger but on the other hand I'm quite happy with a 20 minute charge at 10 amps. It's really quick considering I used to charge and still do charge some of my batteries at 1c meaning it takes a good hour to do them.

Big +1 for ichargers. Best value for money and quite possibly the best charger (within reasonable afordability) that you can buy at the moment.

 

Hi eXraycer!

can you tell me your config about your 1/8 scale onroad?

kv of the tekin?
2x 2s or 2x 3s lipo?

and do you use only 1 gear forward/brake/reverse
or 2 spur gear with servo for brake?

thank you in advance for all

David.

 

Just picked up a Serpent for my self. OK, it is the older 960 but I am thinking of buying the 966 upgrade kit. Anyway I am gathering knowledge and trying to get some ideas happening in regards to my conversion. I wont be racing but I just love the look of these machines so I just wanted one. Might have a little go on a track but I mainly wanted on to just go stupid fast. LOL.

Anyways eXraycer you kept yours as a two speed. I was thinking of ditching the two speed and going with one speed as I think I will have tons of power. Going to go with 6S setup (one 3S per side) and probably something in order of 4000mAh+ and around 40C. That much is easy so far. Motor will be a Tekin T8 2250 and RX8 ESC. Again too simple. Going to make my own motor mount which I have pretty much sussed out so far.

Now I know jack sh!t about these 1/8th on-road cars (except I love the look of them). My Serpent looks to have a spool in the rear but the front has a one way bearing. This means that it will be only braking with the rear wheels. This is what worries me. How good are the brakes with only rear wheels pulling the car up? I was thinking of deleting the front one way bearing but what then???? I will have a locked front and locked rear axle. Wont that handle like crap? Like I said, I wont be racing, but I dont want the car to be an absolute pig neither. I would really like to have the front wheels do some braking. Is there a proper diff I can get for the Serpent 960?

I would appreciate any help eXraycer. I just want to make it a nice, reliable and fast car.

 

Big-block, I bought one of these a little while back (mrx4x, same sort of car) for pretty much the same purpose as you - just wanted to go really fast. Mine is nitro, but it is certainly stupidly fast. In fact I think it would out accelerate my brushless off road cars with ease.

If you are used to driving off road vehicles, driving 1/8 scale on road will seem quite strange, at least it was for me. Firstly, and probably most importantly, the brakes; as you've pointed out due to the one way setup in the front, they only brake the rear wheels, leaving the front to essentially freewheeling with no restriction at all. They work ok at higher speeds when the downforce of the body is pushing down on the rear of the car, but at lower speeds the car has a tendency of wanting to spin out and go backwards unless you are either (very) careful with the trigger, or set the EPA very low.

Second is the handling, which once you get used to it is incredible, but needs to be driven very fast before it makes sense. Because of the freewheeling effect in the front, if you try cornering without enough power on, the resistance in the rear makes the car want to spin out very easily, almost like you have the handbrake on. More power and faster speeds cures this, but obviously takes some getting used to..

Lastly, you need quite a large area, completely free from stones or any debris to drive it. I've found even what appears to be a 'clean' car park, has all kinds of small stones that smash into the low body, get stuck places they shouldn't and tear up the drive belts (which are a pain to replace). Not to mention any small bumps unsettling the car by hitting the body and chassis.

These cars are obviously designed with one purpose in mind, and that's to go around a track as fast as possible, where the brakes, handling and ground clearance aren't an issue. I've thought about setting the front up without the one ways to get that permanent 4wd effect and braking, but I've heard it can cause handling issues. I plan on racing it at some point so I will wait until I try that before modifying anything.

That being said.. They are great fun, and stupidly fast once you get the hang of it.

 

Thanks mate. Pretty much what I have heard so far. I might give it a go around the track but doubt I will be racing it. I am just not competitive by nature but never say never. Still even if I wanted to race it I doubt that the nitro boys will be happy to have an electric on the track. Even as it is my mate had second thoughts about selling the car to me after he found out that I was going to convert it.

I know exactly what you mean by having to go fast to make it handle. These cars are just an upside down wing. No speed=no down force, no down force=no traction. Simple as that. I do want to do some speed runs with it too but finding clean enough area to run it on might be a problem.

I am going to try locking the front axle up and see how it goes. What ever I do it will be reversible just in case handling goes backwards. I am pretty certain that this thing will scream once converted. I have seen numerous examples and all look faster than nitro counterparts. There is even ones out there that have top speeds in excess of 170km/h. If that doesn't give me the speed fix nothing will.

 

No problems. I would be very interested in how it handles/brakes/performs with the front locked. It would be interesting to do a comparison with the standard setup vs. locked front end. I suspect you could use a much more aggressive driving style with the locked front, the standard setup requires you to be very smooth.

The brushless setup will no doubt be faster than nitro, but aside from top speed runs, the nitro setup is enough for me! Will you be using a clutch system with a mechanical brake?

 

I've never driven mine anywhere but a track and wouldn't recommend even trying it on the road or a carpark. they need a groomed surface.
Anyhow, you might try dialing in some abs if your controller supports it. a locked front end will destroy belts and make it push like a dump truck in corners. it is designed like that for a good reason and as stated before they need the downforce to work properly so you got no choice but to drive it like you stole it.
I reckon a more suitable project for anyone wanting a do-it-all onroad car is converting a GT 1/8 or as they call them in Europe, a rallygame.

Good luck with the serpent build, I think 2250kv is overcooking it a bit on 6s but there's a lot of different opinions on that and I don't want to start a debate.

 

I will give it a go on the Lilydale track here in Vic. They do run them there but every second weekend. The weekends they don"t run is electric only cars and I have access during those times. So I think it should be fine.

On locking the front diff thing.......I have spare front pulley/middle shaft and one ways so I would just like to give it a go. If I throw a belt I have plenty of those as well and I will revert the car back to standard with one ways in the front.

I decided to drop the mechanical brakes for the moment just for simplicity sake. Might go back to them later on. I'll see about that. I wanted to leave them but that really pushes the motor far forward to clear the disc. I wasn't sure that I could get the right gearing in there. Anyway what gearing did you run mate and did you run yours on 4S or 6S? Also you kept the two speed setup. Where did you get the adapter to run dual pinion gears on the motor?

What did you mean about the 2250 on 6S overcooking it? Did you mean it will cook the motor or it will be too much speed and power? I rather run higher voltage and lower the speed through gearing to make it a more efficient setup but would like to hear your opinion on that too.

Anyway thanks heaps for your help mate. Your input is highly appreciated. I love working on this car. Even if it turns out that I can't drive it around the track it will look sh!t hot just as a shelf queen. Just love the degree of engineering on these things. Way more involved than anything else RC I have ever worked on. Hopefully I manage to pull off the carbon fiber chassis as well but that will be later on. I want to incorperate the side pods for the batteries into the chassis as all in one piece. Hope fully that will remove some of the weight that the electrical conversion piles on.