Genesis_twin

Hello, I need to upgrade the shock springs on my Genesis due to adding a lot of weight to it . I just saw a post below mentioning new springs, how can I get some?
If they are not available what is the lbs spec of the current spring so I can find some from an industrial supplier.

Thanks

Scouser

Sorry I cant help with the springs but if I were you I would be looking to get a stronger roll cage to protect that beast when it rolls!!! Nice work.

bustergonad

I don't usually like to bring up old threads but..........
DAMN DUDE!!!!!!!!!!!!!!!!!! [X(][X(][X(]
Can we get some more info on this beast???

Buster

Genesis_twin

Thanks guys. Here's the story-

Years ago I mounted an OS FT120 to a RC car I built using a 4WD chain drive kit with a custom rail and plate chassis. The thing went like a bat out of hell but kept braking the chain, diffs and dog-bones. I retired it after my 45 deg drive gears stripped out. At my current job I work next to a guy that is an RC nut and he keeps bringing in his toys. He has got me hooked on RC again. I started looking for a monster truck that would allow me to use my old engine. I wanted one with the transmission placed such that I would not need 45 deg drive gears. The Genesis looked good to me so I got one on e-bay w/o the engine.

I am using the transmission spur gears and mounts adapted to fit onto my clutch. The FT120 only gets to about 10,000 RPM so I figured the gearing would be OK. I'm attaching some more old pics. Not shown is the front motor mount and roll cage I built (ya I already thought of that Scouser, thanks anyway) The stock roll bar would not do much to protect it and was in the way of my motor mount.

I have run it 4 times so far,
1 in the back yard- proved I need to strengthen the front of my roll cage.
2 at work on pavement, did donuts with the lifted front tire spinning up enough to make it twice its diameter
3 brought it home, got stuck under tree- broken front diff drive cup []
4 brazed both front diff cup to housing = locked front diff. Brought to work, had radio troubles but worked well enough to slam it into reverse shredding 4 gears in the transmission and broke a rear diff drive cup [:@]

Now I am waiting on a new tranny. I locked the rear diff also but I would rather have working diffs.
I am hoping I had the old material drive cups.

My biggest problem is flipping over due to the added weight, high CG and too soft springs. The locked front diff made it worse.
I may have solved part of this problem without new springs. I attached the bottom of the 8 shocks to the overhead shock tie rod end mounting holes on the lower A arms. I mounted the tie rod ends to the lower knuckle hinge pin point using the long screw from the original shock mounting point. This has lowered the truck about an inch and the shocks have a lot more leverage. I will see when it is back together.

I want to add a microswitch that will disable to reverse servo until the brakes are on. Which wire should I use on the servo to disable it red white or black?

Also does anyone know the gear ratio from the transmission to the wheels for 1st 2nd and 3rd gear? Ie: if I spin the first gear spur gear at 10000 rpm what rpm will the wheels spin?

Thanks

bustergonad

I don't know about the gear ratio's but you could probably figure them out by finding out what number of teeth on each gear and going from there. CEN's website has nearly all the teeth numbers on their parts list/exploded diagrams.
I like the idea of the PC fan in there, does it help with the cooling in a significant way?? I've been toying with the idea of trying to stuff a skinny fan in between the rear shock tower and the engine. I don't really care about the extra weight of the fan and battery pack, the gen already weighs over 17lb what's an extra few ounces going to do

Buster

CrashBurn69

My Feedback: (1)

The heavier springs I have read about have been a #49 bought at a local hardward store. That would be your best bet, but you might need a different number, but thats where they got them.

Jected

Hey mate. 1st of all nice setup. Always good to see something new. I would recommend using the integy alloy adjustable super duty shocks (without the piggy back setup-more trouble than they are worth I reckon). Also when used in conjuncyion with the newera alloy arms, there is actually a mounting point for them closer to the steering knuckle, so they are a perfect fit.

xmodforum

My Feedback: (1)

holey ***self edit*** my **self edit** god
Gives me some ideas now. Time to break out autocad

madmark

just read an industrial inovations magazine at work today,which had [cant think of the name ] a spring which was a couple of times the strenght of a standard type spring of the same lenght , thickness etc ,will get more info on it tomorrow , address, phone no. , their an american company ,
well worth checking out , might find what ur looking for.

Jected

The only problem with the standard Gen shocks is that they are plastic and leak. Go a good quality alloy shock. They won't leak or blow out like plastic ones.

mulletman

how long can you carry a cat walk with that baby?

tomandemmy

My Feedback: (1)

i have the integy piggyback for a savage not sure if they are gonna work but im gonna try.

RunX

I have done a few to mods to my genesis and will post a pic later,if u want to u can use the old shock bodies but replace the standard red spring with Rex x(Xterminator buggy) blue or white stiff springs but use the rear ones as they are longer and 8 of them will surely do the job! Them spring will go over but with a nice tight fit.I have only six(6) shocks on the truck,2 rear,2front and 2 for the top shocks with 35silicon oil and it works very well for those who want to have more responsive suspension but with out more weight.Help this tip works for all as it does for me!

Genesis_twin

Thanks for the info RunX, I was thinking of using the new CEN aluminum shocks when they come out and dumping the 4 extra shocks. The springs you mention should make it possible. I have taken off the top shocks because I kept breaking the rod ends but
I still like the idea, they act like a sway bar by pushing down on the side opposite of the compressed side.

mulletman, What the heck is a cat walk? Friday I was doing full throttle high speed 180 deg. turns on grass, It would lift up on 2 wheels and when the lifted wheels spun faster they acted like gyros and I could control it through the turn easily on 2 wheels every time.

mulletman

wheelie? or ride on the back wheels

Genesis_twin

Oh wheelie... I'm from the old school. With the FT-120 it would not wheelie. Probably too heavy, it weighed 21.9 Lbs and the fuel tank is in front. The tires will just spin out.

It might wheelie with the center diff lock installed but I don't want to stress it out. I have gone at least a gallon without breaking any differential parts which was a problem for me.

Lack of power was not a problem, it would easily out run my E-maxx with fresh 3600 batteries and in 2nd gear.

With my Genesis gear ratio I'm barely even getting 2nd gear and the 3rd gear clutch looks brand new. With the new engine at almost twice the HP and adjusting the gears I expect it to really scream. If the drive train holds together maybe it will cat walk.

cossie

just because you have twice the hp it doesnt mean its going to go fast its rpm you need to go fast and make it scream

Genesis_twin

That is why I am using the 43 and 39 tooth pinion gears. It did seem to bog out at the top end in tall grass. That will not be an issue any more and getting third gear should be do-able. I realize that if I have to loosen the 2nd and 3rd gear clutches the final drive RPM will be less then stock and the truck will be slower then stock. I have been very happy with the performance as it was. I do not race it . The benefit of the 4-stroke is the torque curve and it's sound. I don't really like that 1,000 angry bumble bee sound from the 2 strokes and I can drive mine on my street here in the burbs without pissin off the neighbors.

Ok, did some math, let me know if it's wrong:

Stock 1st gear- 17t / 43t = 2.529:1 ratio * 25,000 RPM = 9,885 RPM at main trans shaft
Stock 2nd gear- 21t / 39t = 1.857:1 ratio * 25,000 RPM = 13,462 RPM

4strk 1st gear- 39t / 43t = 1.102:1 ratio * 10,000 RPM = 9,074 RPM at main trans shaft
4strk 2nd gear- 43t / 39t = 1:1.102 ratio * 10,000 RPM = 11,020 RPM

This assumes that the listed engine RPM is correct.

OK If i wanted higher speed I would need to dump first gear and use the Internal Trans. Spur Gear(46T) as my pinion and the new 25T gear as the spur.
1.84 ratio * 10,000 RPM = 18,400 at main trans shaft.

Nahh, I think I'll keep torque vs speed for now.

Genesis_twin

Oh ya, If I want more speed I put more air in the tires.

Approximate tire diameters:
Stock - 7.5 inch
"Dirt mode" maybe 1-2 Psi - 8.0 inch
"Street mode" maybe 5 Psi- 9.5 inch

It won't even measure on my auto style pressure gage.

cossie

which in turn puts added strain on the transmissiona nd acclerates slower

Genesis_twin

superdave420

Not true. more air in the tire means LESS contact patch to the terra-firma which results in LESS friction, which in turn FREES up the tranny and takes more strain OFF the drivetrain.

Um think about 4 WD rock crawlers that take most of the air out of the tires to GAIN more friction

poor judgement

i think cossie is getting at the larger diameter of the tyres, which will add a little more strain to the engine etc, as its just the same as gearing the truck up slightly.

cant see it bothering that engine at all tho tbh.

its a work of art Twin Gen, bloody good work man! but i would advise knowing when to stop tho! these things take over ur life.... oh it did already? lol. nah seriously, ive gone too far with my silly funfactor, and ive hit probs that i never expected, hope u dont have similar issues.

keep it up!

doh forgot - the 46t gear u mentioned - it doesnt by any chance have the same cutout on the back as the 43 and 39 tooth stock spurs does it?

superdave420

I have personally witnessed this SICK @$$ wicked beast run quite a few times ( I work with him )

this is the fastest/ biggest nitro sucking RC truck I have ever seen. I had serious doubts about it at first but once I saw it run I was blown away.

a dual 7 cell E-maxx is like a tyco truck head to head with this. left the E-maxx in the DUST.

I would have to say that the Twin goes at least 40-45 MPH in FIRST GEAR. we have not been able to find a place that is safe enough to get it into 2nd gear let alone 3rd.

there is a lot of mass here and even in first gear can do a LOT of damage to a person.

just plain insane. we need to get video of this to show what it can really do.

and now he has a new TWIN with twice the power in it. HOLY SHICKEYS

so I am vouching for the insane sickness that this TRUE MONSTER beholds

poor judgement

lol, sounds like fun - any chance of some vids?

my lil truck scares me enough, that monster... well what can i say - go on, give us a vid!