Yusa Rally On Road conversion

[lincpimp]

So, I bought another rc! I guess the other 40 vehicles were lonely! I think I need help1

Anyway, the car is very nice, looks alot like an inferno gt or ofna gtp. Came with the rolling chassis, header and tuned pipe, motor mount, and 2 speed clutchbell. My intended application is straight line speed, and some drifting. Mech brakes will be employed, due to the retention of the clutch and 2 speed. I am going to use a modified traxxas 4tec threaded clutchbell with a tekno electri clutch. I will also try out the integy 3 shoe clutch, maybe it will hold well enough to get this car moving. Heres the clutch:

http://www3.towerhobbies.com/cgi-bin...?&I=LXKVL0&P=7

I plan on using an aveox 36/24/1.5, a 2600kv motor, similar in size to a feigao l can motor. I will run it on 4s lipo, 3000mah milwaukee drill cells arranged in 2 packs of 2s2p (thanks briang!). The trusty Mamba Max will be employed, hopefully it will be able to run the motor effectively, considering the aveox is very similar to a neu motor, that can cause issues with the MM. My use of the clutch should cure any startup issues. Plus Artur (griffinru) has done his stage 1 mod to this esc, so that should help it survive!

Car comes with buggy diffs, 43/13, and a 2 speed center drive, with 44 and 48 tooth spurs. Stock clutchbell is a 17/21 tooth. I will use traxxas screw on gears, 15/20 for this application. This will yeild the following speeds:

1st gear:

Differential Ratio: 3.3076923076923075
Spur Tooth Count: 48
Pinion Tooth Count: 15
Total Voltage: 14.8
Motor KV: 2600
Tire Diameter (inches): 4
Spur/Pinion Ratio: 3.2 : 1
Total Ratio: 10.58462 : 1
Total Motor Speed: 38480 RPM
Vehicle Speed: 43.26 MPH (69.49km/h)

2nd gear:

Differential Ratio: 3.3076923076923075
Spur Tooth Count: 44
Pinion Tooth Count: 20
Total Voltage: 14.8
Motor KV: 2600
Tire Diameter (inches): 4
Spur/Pinion Ratio: 2.2 : 1
Total Ratio: 7.27692 : 1
Total Motor Speed: 38480 RPM
Vehicle Speed: 62.93 MPH (101.08km/h)


I know this sounds a bit much on 4s, especially with a smaller motor, but I hope the combo of a 2 speed and a clutch will allow it to work well. Plus it is an on-road car.

Pics will follow soon, I have the chassis cleaned off and the servos mounted and trimmed. I have also constructed two battery trays out of kydex (thanks rchippie!) with some rubber padding. My motor mount is partially done, just waiting for the 15t first gear pinion to arrive and I can final mount the motor and clean up the mount itself.

The vehicle looks to be well built, quality is at the same level as my ofna mbx buggy, the closest thing I have to the yusa. Everything has fit fine, except I had to fille the steering servo mount holes slightly to get my servo fitted.

[tashpop]

sounds like an awsome project. i have simular plan for mine aswell. i figured i would start with a speed demon and eventually look into raising it and going rally if i get bored. i plan on a 12s1p a123 app. for mine though. just waiting for the holiday madness to end so i can begin to fund the project. i'll be watching yours closely.

question---have you opened the diffs up? did they have any lube and what weight are you using if you've been in them yet.

[lincpimp]

I have not had a chance to get into the diffs, however I plan on putting some heavy oil in the rear, probably some traxxas 50k as I have that laying around. The front will get 5k or 7k, most likely the 7k as I plan on drifting it and would prefer the stability that heavier fluid offers. I do not plan to race it as we do not have an onroad track anywhere close. I will just be "road bashing" with it!

Post up a thread of your project Tashpop, it will be interesting to see a hv setup in this car!

[tashpop]

i will when i get it started. right now the roller is just collecting dust in the garage.

[lincpimp]

Here are some pics of the project in its current state. Sorry about the random wiring, I need to make a front and rear upper deck to mount the electronics to.








Viper body, Yeah!

[MetalMan]

Is it just the camera angle or is the front wider than the rear? Looks like a cool/fun project .

[lincpimp]

Yeah, it was an off angle shot!

It looks to be a fun project. I also have a 1300 kv motor of the same size/brand. I could reconfigure my cells to an 8s1p 3000mah pack. Same motor rpm, I would need a hv esc, like the great planes 60amp model. Would be interesting to see how temps and runtimes compared. I will see how it works first with the 4s setup!

[lincpimp]

Heres the info on what this setup would do with a 1300kv motor on 10s lipo.

Differential Ratio: 3.3076923076923075
Spur Tooth Count: 44
Pinion Tooth Count: 20
Total Voltage: 37
Motor KV: 1300
Tire Diameter (inches): 4
Spur/Pinion Ratio: 2.2 : 1
Total Ratio: 7.27692 : 1
Total Motor Speed: 48100 RPM
Vehicle Speed: 78.66 MPH (126.35km/h)

I will most likely try this setup after I get it running with the 2600 kv motor. Both motors are the same size aveox motors, so it will be a direct comparision (if I use 8s lipo it yeilds the same speed). I will have to go to 10s to get some more speed, but the mfg spec the motor at a higher rpm than I will be using so I hope it works.

[lincpimp]

Ok, pretty much finished with this project. My motor mount is done, and I have made an esc mount plate for the quark airmaster 125. Wired it up, and set my new futaba 3pm to mix the brake channel (3rd) with the throttle channel (2nd). I programmed the esc and it works great. Nice that the brake servo does not move with the throttle, only when braking. I will have to do this mod with my revo too.

Everything looked good, so I put the car on a stand and tried it out. The 3 shoes clutch seems to work well, but there was an odd noise. After much investigaton I found that the tekno elktri-clutch was wobbling on the motor shaft. Took it apart and found that the 5mm hole was slightly too big, allowing the adapter to move on the motor shaft. I even tried it on other motors and it was too loose on them too. I contacted tekno and they are going to ship me another one. Good service and a very quick reply to my emails.

Looks like this one is on the back burner, maybe the tmaxx parts will show up and I can finish it first!

[tashpop]

any update on this?

[lincpimp]

Well, I received the new clutch bell adapter from tekno yesterday, but I may not get a chance to install and test it till next week. Time is stretched thin due to work and the mardi gras season.

Throw me something, mister! I will be yelling that tomorrow during the parade!

[lincpimp]

A while since the last update...

Tried to sell it, but did not have any success, oh well. Was looking at my motor selection and found the 1300kv aveox. I think that I will try it in this car on 8s and 10s. I have enough cells to do both and the pair of 5s packs are already made. I also have a turnigy hv esc coming from UH. Sounds like I just resurected the project!

I will have some more pics when everything else arrives and I get it wired up!

[lincpimp]

Put some wrench time on this car today. I put the replacement clutch adapter on, and it runs true, no wobbles! Set the mesh, programmed the radio and went out for a test run. I left the quark airmaster 125 and the aveox 2600kv motor in for the time being, and am using a 4s 6000 lipo. Plenty of power from the aveox, but it was not shifting into second. Tried adjusting it, but did not have any success.

So I took the 2 speed apart, and had a good look at it. What I thought was the adjusting screw was actully not. Turn out the shifting mechanism is controlled by a clutch. It is a circular platic disk about 8mm thick that is cut in half, and has 2 bolts with springs holding the 2 halves together. Those bolts are placed near the ends of the 2 halves. Each side has an adjustment screw in the center of the clutch shoe with a ball bearing behind it. The main shaft has a hub machined on it with 2 flat spots. They act as ramps, and as the spring pressure is relieved by the centifugal force the ball bearings ramp along the flat areas, causing the 2 halves to seperate and make contact with the clutch bell area of the second gear hub.

Problem is, the springs are too heavy, and no amount of playing with it would make it work. I ended up taking one of the bolts and springs out, so that side can open up and grab the bell, much like a drum brake on a car. That worked, and I bench tested the setup a few times. Took it apart and the shoes had a nice wear pattern over almost 360 deg of the surface. Hope this works, as I am anxious to see how well this works on 5s!

Then it rained, so no testing

heres a few pics, the wiring is tempory till I get some performance testing done and decide if I like it this way.

[lincpimp]

Thinking about selling this, any interest?

[Arct1k]

hippie was looking for GTP's