Help creating a low budget Hyper 7 brushless
 

Hi guys, been a while since I've been around the forum doing more than lite reading... But it's time to start playing again :-)

What I'm looking to do is throw togeather a new basher with my upcoming birthday budget, ~$450 USD.

What I have to work with is a Hyper 7 PBS that needs a little repair from a runaway incident of the fuelly days. Chassis is just bent enough to warrant replacing and the front driveshaft is tweaked too. Other than that the diffs, linkage and such is in good working order. Still have good radio, servos, ect to work with.

What I don't have yet is a MMM Esc and motor combo, lipo's, and what ever else it takes to convert to brushless.

I'm not a noob, but advise on the best budget items would be appreciated.
I am thinking 6s total with 2x3s 5000mah zippy lipo's and custom made CF trays. But it's spur gear/ motor mount where I'm stalled.

Was wondering if a tranny from the nexx8 electric would provide a cheap electric swap alternative?

A MMM 2200 combo would be a great motor esc combo for this and its really hard to beat the price, performance, reliability, quality, and customer service that backs it up. You may find something cheaper but it will not be on par in the rest of those categories. You will also need a motor mount, the RC-Monster store has them, as well as a pinion gear and battery tray that you will need. Other than that you need a lipo and a lipo capable charger if you don't already have one. Lipos can be found in many places, RC-Monster also has them but many people go to HobbyCity for the zippie lipos, I have also seen some good prices on lipos from many other hobby distributers lately. I prefer NeuEnergy Lipos for their performance/price value. You will only need a 4s pack unless you are planning on an all out speed demon, 4s with the 2200 combo on a buggy will easily get you 40+MPH before you have any heat issues.

Yah, the Mamba is a no brainer from my point of view ( I did a dual fet board mod on a mamba max a while back that was awesome, though the max amps lipo's were a big let down...)

The RCM mount I'm aware of, but I am under the impression that getting a composite spur gear on the center diff is a no go on the hyper 7?

too bad your waiting, could take advantage of the sale and get 20% off esc and off the clearenced motors.

This is a budget combo set: http://www.okhobby.com/product.php?id_product=1234

Tashpop, was up late last night reading the castle sale thread :-) very sweet. I'll be placing an order for a 1520 today. Thanks for mentioning the sale though, had I not already found it yesterday it would have made a world of good for this persuit.

Too bad they don't have the MMM's on sale :-)

I'm half considering redirecting the modded MM from it's 10th scale duties to run the 1520... But I really like the idea of using a MMM so I don't have to worry about the reliability of the very finite soldering I've done in the mod process.

Dj sparky that IS a cheap combo, but I'd rather spend twice that to have the castle logo on my car :-) seriously though I realy like the time and effort guys like Patrick and the support team at Castle put into this site, so I'd rather pay them a portion of my playing funds. Thank you PM's are good, but cash in their pocket is better :-)

Order's in, got a 1518 instead of the 1520 as the 1800 kv will keep the motor closer to the 35,000 rpm sweet spot for more of the throttle range at 6S, and it's just a touch less massive to fit in the buggy ;-)

Well said! It's money well spent, knowing that IF something does go wrong you have the support of Castle. It's cheaper in the long run to buy castle the first time rather than cheaping out on the initial purchase only to replace it with something from Castle in 3 months. I've only owned one esc that wasn't from Castle, it was a Novak HV that lasted like 2 months then I put a MM in it's place. The only car esc that CC makes that I don't own or haven't owned is the Micro Pro

Well, I've started working out the future layout for the hyper. I managed to find a center diff in my spare parts that will take a nylon gear (ofna ultra mbx iirc), it's longer than the hyper 7 but that's fine as I was going to relocate the CD anyway.

I mocked up the 1518 with a trimmed toilet paper roll :-) I plan on either making a diff/motor mount, or buy the RCM universal set that puts the motor over the diff, but that would be a large portion of the budget. Either way I want the motor centered over the center diff.

I found a 16mm x 6mm dog-bone to put the CD right at the rear diff, and with the spur gear towards the front of the buggy it would locate the motor just above the center of gravity on the chassis. I'll either find the correct length front driveshaft or build a 2 piece with a carrier bearing and cva.

I could locate the batteries on either side of the chassis and adjust them front to rear to change the weight bias... That's the way it's planned today anyway :neutral:

If you need a hyper 7 parts car PM me :)

has battery trays driveline etc.

Have a quick request from guys who run 1/8th brushless buggies....

I've settled on a 6S/1580/MMM setup, question I have is wieght VS runtime, i.e. I'm looking at either 2x3S5000 in series at ~2lbs -or- 2x6S4000 parallel at 2.8lbs
Basically it's 5ah at 2lbs, or 8ah at 2.8... is the extra .8lbs worth a 40% increase in capacity. Total wieght (just a quick calc w/o all the parts assembled yet) 5ah= 10.4lbs, 8ah= 11.2lbs

Thats a heavy buggy! My truggy RTR is only 10Lbs

Yah, I'm already looking at narrowing the stock aluminum pan, making CF batt trays/splash guards, and going aluminum on all the suspension components to lighten it up. But that's all a down-the-road thing as I can only spend so much at a time :-)

Priority #1 is getting it up and running

Woohoo!!! And so it begins :-)

http://i217.photobucket.com/albums/c...5/51d7d543.jpg

OK, a quick update. I've made a few purchases to add to the 1518, still on budget but I've had to add a second round of buying for a later date.

So I've got the 1518, ordered a pair of turnigy 4s 40c 5000mah lipo's (to be ran in parallel for the time being), a set of dirt tires, a MMM, a Savox titanium ultra speed servo, a mod 1 16t pinion, a mod 1 14t pinion, and a pair of losi battery trays.

I fabbed up a quick and dirty motor mount plate that screws to the original diff bracket so I can play when the parts are all here (no jumping or hard core bashing with it).

I would love to see the RCM universal mount back in stock as it's what I intend to run long term, turnigy nano-techs in the USA warehouse, and the Mamba XL HV here at RCM (or anywhere else it may show up if not here).

http://i217.photobucket.com/albums/c...5/11d68f98.jpg

Will relocate the diff later when I get a long term motor mount and the correct length dogbones.

I think you'll find that the alloy parts are actually heavier than the plastic. Weight aside, I would stick with plastic anyway. It can flex a bit and bend back, once the aluminum bends that's about it. Also, plastic is cheaper to replace so if/when you do bust an a-arm no big deal.

Good start on the buggy, it's cool how even older vehicles can still be awesome when you throw a solid brushless system in there! One upgrade you may want to look at is big bore shocks. They will help a lot, especially if you plan on using the hefty dual 4S 5000mah battery setup. I had those same 13mm shocks on my Jammin (funny how they actually used to be considered big bores!) and replaced them with Hyper 9 17mm big bores, but there are lots of other popular ones too like the Ofna 16mm, or HotBodies. Many can be found for cheap on Ebay.

P.S. Cool little snake you have in the background there! I have a few ball pythons myself. Awesome creatures they are.

Thanks for the heads up on the plastic vs. Aluminum, I knew the aluminum was more brittle but I really thought it was lighter. I do have a full set of spares I've never used, even after the runaway that killed it last time... Suppose the big bore shocks could replace those in the line of wanted upgrades. Off to put some in the eBay watch list. Thanks for keeping up the support, I really do appreciate the advise.

Ps. The snake is just a little Garder the kids wanted to save from the winter cold :-) My son has a beautiful 3 foot plus King snake that's a legit pet.

I really like king snakes, they seem to be one of the best colubrids to keep as a pet, more mellow than cornsakes, ratsnakes, etc. at least from my experience.

Anyway, back on-topic!

Well, I've officially gone $82 over budget :-) decided I had to get a 1717 from castle before they were gone... It will eventually end up in some form of monster truck propably a MGT with a center diff conversion (I've got two extra ofna buggy spider diffs).

Yes, back on topic now

LOL this thing is going to be a real tank with dual 4S 5000mah packs and a 1717. Stock up on diff parts and CVDs, maybe even consider a Slipperential later on when the budget allows. Also, get some stiff springs for whatever shocks you decide on.

1717 is a little much for this chassis, it'll be going in a monster truck at a future date :-) I'm crazy, not insane hahaha :-)

Still, even a 1518 is overkill in a buggy. Thats why I bought one for my new LRP buggy:yipi:

Your conversion will be one of a kind, I like your layout plan.

Thomas G

http://i217.photobucket.com/albums/c...5/88d3e527.jpg

Well at this point I've patched the buggy togeather so that I could run it just to test the electronics. I found that the Savox ultra speed servo pulled way to much current from the MMM BEC circuit resulting in shut downs. So I grabbed my CC BEC and wired it in (still need to shrink wrap it again) to power just the servo. Works like a charm, this servo is really impressive on 6 volts with enough amperage to feed the beast.

I'm still planning on flipping the motor around and locating the CD at the back of the buggy but untill the RCM universal diff/motor mounts are back in stock it'll be in this layout. I think the steering servo can remain in it's location from here on out.

I hope the lipos will show up tomarrow (day #7 of USPS 1-3 day priority mail) so that I can start mounting the trays and experience this rig on 4S. I did my testing with a 2S maxcrapp that was salvaged from a 3S pack (4 months old and they wouldn't warantee it because I cut it open to isolate the bad cell and save the rest of the pack...)

So far I like the layout with all the stuff centered in the chassis, the motor is high above the chassis plate but I think it's a good compromise to be able to run a pair of large lipo's for power and run time. Can't wait to get the lipo's installed and running.

Here's a pic of what it should look like with the trays installed.
http://i217.photobucket.com/albums/c...5/16232e5d.jpg

:oops:Batteries showed up today and I found a critical flaw. I did all my measurements by the pack size, not accounting for the 8 gauge wires. The wires basically make the packs about 12mm wider on one end :-( that means I've got to relocate my radio and BEC.

I think the jist is that the Mamba XL and the diff relocation need to happen sooner than I had planned. I do see that the XL is on the castle sight now, but still no word on when the mount will be back in stock.

Here's a pic of the batteries in the chassis, not mounted but just for reference.
http://i217.photobucket.com/albums/c...5/f8e3ae44.jpg

Another update... I have been runnung the car some on 6S, just have the batteries ziptied down for the time being. I had to make a pair of chassis braces with some spare turnbuckles and a second CD top plate. (Pic to follow)

I found that the 1518/6S combo is way hard on tires (blew my new tires to pieces, shredded one spare, and I'm on the bald OEM ofna's as a last resort now...) so I've enabled torque control and lightened up on the throttle. Looks like I'm setting some $$ aside for a set of OFNA on road belted tredded tires and a set of dirts I'll have to tape myself.

I got a PM from Mike friday and it seems the universal mount will become available this next week, I went ahead and ordered the Mamba XL from castle as Mike doesn't have an arival date yet, so I can start running my matched 4S packs. Currently using a new 4S turnigy with an OLD max crap 2S in series to get 6S. It's a bad combo the MA pack runs hotter than the turnigy and drains much faster so I've got to limit drive time as the MMM LVC doesn't know if one pack is lower than the other...

I also opened up the spider CD and packed it with grease to help the front tires not unload so agressivley. The 1518 was turning them to pizza the moment they come off the ground. I also have to be good about backing off the throttle a bit to let the front contact the ground enough to turn :-) I'm loving it :party:

I would definitely recommend not running the Turnigy and MA packs again in that series config. You have already seen how the packs will behave, and it's pretty much a recipe for disaster. If the MA pack goes it could take the new Turnigy with it, maybe the ESC and motor too. Hate to see something like that happen.

What did you have in the CD before packing it with grease? Try some 50k or 100k silicone oil next time you rebuild the diff and see how that compares to the grease.

SimpleChamp, I opened up the CD to try to get an idea of what was in it, only to find they come lubed but otherwise dry from OFNA :gasp:

I used the grease as I don't have anything else handy. Even with the severe drag of the grease the fronts still unload pretty heavily. I may look into a torsen diff if I can find one cheap.

The MA pack is holding up well enough now with the "Torque control" enabled. Seems that the MA pack has a low (actual) C rating, who would have thought :rofl:

I did consider a pack failure... I suppose that aside from fire, if the pack goes dead short it will just act like a shunt between the turnigy and ESC, can't see that doing more than slowing down a bunch. If the pack goes to an open circuit it'll just shut the buggy down entirely. So as long as I pull the pack before flames go up I should be good. Either way I'm short cycling the packs to keep low voltage out of the equation, and I've limited the amp draws on them as well. Hopefully I'll get away with it till the XL arrives here.

Just put in an order it Amain, should square me up. Now just waiting on the RCM mount and a couple custom length dog bones for relocating the CD...

I think you'll find that some heavy silicone oil will work much better than the grease at keeping the CD from unloading.

Thanks SC,
One of the items I ordered last night was some 500,000ct diff oil :-) Along with 5 & 7K diff oil, Ofna belted tires, Ofna Inch up rims, a JConcepts Illusion body (no nitro holes), Chrome paint, 6.5mm Castle Connectors, battery straps, glue, and some small bits and pieces.

Update: I've been running the car for a few weeks now. The diffs ended up all being dry aside from assembly lube (funny what you don't need running nitro), they are currently 7K,500K,5K what a HUGE improvement!

I also received my Mamba XL and have started looking at the new layout. Seems that the rear diff relocation will have to wait until I begin fabbing a new chassis.

[IMG]http://i217.photobucket.com/albums/c...5/8c37954d.jpg[/IMG]

The XL really is extra large...
[IMG]http://i217.photobucket.com/albums/c...5/d8bbdba2.jpg[/IMG]

What's the full RTR weight on that thing?

Dunno exactly, but I believe in it's previous state, with the MMM, it was right at 10.2lbs ready to run. At first I was concerned about the weight, but after running it on even 6S it is in need of all the traction I can muster. With the XL and swapping the motor forward I hope to shift even more mass twards the front end. As it is the front tires barley contact the ground on acceleration, at 8S it will be even more aggressive.

I'll try to run it over to the post office after the XL is in and get the exact weight.

Better start building a stockpile of diff gears and CVDs. Thing looks like it would eat hardened steel and sh*t Integy aluminum LOL!

Man, space is a premium on that chassis!!! Where are you going to stick the steering servo? Looking good, what speed do you plan to gear this beast for? 80mph?!?!?!?!

Linc, the steering servo is under the front driveline, the RCM mount sits a little high providing enough space :-) I'd say finding a spot for the servo was the most difficult thing so far.

I'll take a few more pics and a video tonight, it's not actually all that tight in there. I tried to leave plenty of room around the XL and 1518 for air flow, when you look through the front window (cut out) on the body you can see right out the back on either side of the shock tower...

I haven't got into gearing much as I'm going to rely on the data logging and temps for the best ratio. I may be looking into a 1527 1.5d sooner than later to get everything I'm after. Should know after a bunch of test and tune this weekend.

DrKnow after reading the OP title I say this is no longer of those means. Looks more like an insanely, crazy, lets blow up some gears build to me. With that power system I would say get yourself some solid chunks of rubber on the wheels, no ballooning, plenty of power to move it. I hope to see some driveline carnage that no other system has caused before. I am thinking I would like to see some twisted shafts, or teeth through a diff case, something along those lines would make me happy.

Anyways, stellar build and happy thrashings!

Reno, I know the thread title makes it seem like I don't have an idea of how to accomplish the goal but I am realy more looking to the gents here on the forum to watch my progress and offer helpful advise (like simplechamp suggesting silicone oil vs. The grease I thought would be sufficient). At this point the car is driveable, but no where near complete, so I will still need gobs of advise as it progress'.

I still want to make a custom chassis and shift around the components as the motor and XL are pretty high above COG and it's not as weight forward as I think it may need to be.