Revorocks's Hyper 7 100+mph project

[Revorocks]

I've been running this project for a while now, it's making slow progress but is getting there. The goal is 100mph or above!

Started out like this, second hand Hyper on eBay for £35 posted!



After some cleaning and maintenance:



Converted it and put a MMM 2200KV combo running 5S, 19/46
Ran great, very fast, but broke after a while.







Got some upgrades:

CNC Knuckles
CNC Uprights
CNC Hinge Pin Holders
CNC Wheel nuts
CNC Chassis Braces
CNC Steering Plate
Hong Nor 16mm Big Bores
Nanda Block Tyres on black dish wheels
New Bearings
Carbon Top Deck
T-Bone Racing Bumpers
Savox SC-1258









Looks much better now, and this is the stage I started the speed project.

[Revorocks]

First, I found an Neu 1717 on a forum, like new so I snapped it up.
Really happy with this motor, it's a beast compared to the 1515.







I then started thinking about how to gear it, because the maximum it can be geared with the Ansmann mount is about 21/46, which is pretty slow with a 1717 :P

I designed a custom mount on Google Sketchup.



After some rendering (only learnt how to do this yesterday :D)



Eventually, after some quotes I decided it was too expensive, because to take advantage of the massive slots I would need an enormous pinion gear, we're talking 40T!

I decided instead to figure out a way of making the centre diff smaller, instead of a 46T spur, maybe 28T or so.

I came up with this:





I think it should work quite well. It takes an 8mm bore mod1 pinion, needs to be 8mm as the bearings at 8mm, so it needs to fit over them.
I'll use a collar and set screw to stop it the bearings sliding off.

[Revorocks]

Additionally I bought an RC Monster motor mount, 30T pinion and drive cups.

Did a test fit of the 1717 with the new mount, fitted very nicely after using some washers.



MMM, SS screws :D



Cleaned out the centre diff while I was at it.





Just clears the chassis.





Now the MMM isn't going to be up for a speed run with a 1717, so I also bought a Mamba XL2 :D

I've got a new shell on the way,as well as some GRP Rally tyres, these are supposed to be very good for speed runs and hold up well above 100mph.

So that's where it is now, currently waiting on the machining, a custom pinion, and then I need to get some custom length driveshafts made, or shorten the current ones. Anyone know the best way of doing that?

[MiamizFinest]

Nice ride!! If you don't mind me asking, could you link me those battery trays?! Are they 100% flat on the bottom??

[Revorocks]

Originally Posted by MiamizFinest

Nice ride!! If you don't mind me asking, could you link me those battery trays?! Are they 100% flat on the bottom??

Thanks, no they are not flat on the bottom, they are raised up but you could remove them with a dremel. The screws wouldn't have much material to grip to though if you did.

I took some pics for you.





They comfortably fit 5000mah 5S 30C packs.



I got them from TC Models.

[_paralyzed_]

2 things-

1. I don't understand what you did that you need shorter driveshafts. Did you change the center diff? Figure out what length you need. If you need 100mm dogbones you can usually find something within a mm or two on ebay by searching "100mm", then "99mm"or "101mm" etc., etc.

2. A buggy is light enough, you don't need nearly that much motor to reach 100mph. You can reach 100mph on 6s with an MMM and a 1512 size 2650kv motor. Additionally, the extra kv over the 1717 makes gearing much much easier. I just bought a Hyper 8.5 buggy with a 2650kv 1512 for the exact purpose of running 100mph to blow away the xo-1's.

You can certainly do it your way, and it will be cool, but there are much easier ways.

[Revorocks]

Originally Posted by _paralyzed_

2 things-

1. I don't understand what you did that you need shorter driveshafts. Did you change the center diff? Figure out what length you need. If you need 100mm dogbones you can usually find something within a mm or two on ebay by searching "100mm", then "99mm"or "101mm" etc., etc.

2. A buggy is light enough, you don't need nearly that much motor to reach 100mph. You can reach 100mph on 6s with an MMM and a 1512 size 2650kv motor. Additionally, the extra kv over the 1717 makes gearing much much easier. I just bought a Hyper 8.5 buggy with a 2650kv 1512 for the exact purpose of running 100mph to blow away the xo-1's.

You can certainly do it your way, and it will be cool, but there are much easier ways.

1. The centre diff has drive cups which are set inside the diff meaning no grub screw is needed. With my layshaft design it will have to have a grub screw, so the drive cups are longer, meaning I have to use shorter shafts. I can't simply slide the cups further in either because the. I won't be able to access the grub screw

2. Fair comment, yes it would be far less hassle to break 100 with. That setup, but with mine I can basically run up to 8s and gear it higher. I'm hoping for considerably more than 100 with this. It's my first speed car though so I am sure things won't be quite that easy :P

[x-y]

for arrive at this speed you will need 6s + a very big pinion of +35-40t ....... and quality onroad tyres ....

http://www.rc-monster.com/forum/showthread.php?t=30362

[Revorocks]

Originally Posted by x-y

for arrive at this speed you will need 6s + a very big pinion of +35-40t ....... and quality onroad tyres ....

http://www.rc-monster.com/forum/showthread.php?t=30362

I'll be running 6S, 7S and possibly 8S.

Gearing will be 30/36 minimum (stock is 46T spur), and tyre wise, GRP's

[ZippyBasher]

Subscribed... Good Job so far man. You definatley have a great plan for going about this...

I think the 1717 is a good choice as well because it can probably take close to a 1:1 ratio on the pinion/spur, with the GRP tires being so light it will run fine. Probably giving you more attempts at 100+ before it heats up too much as well. Just gotta run some extra voltage... The GRPs are just great for the speed runs too!

[cmac]

I just picked up a set of those tires from Amain for my Losi 8ight. I might try to do something similar but with the 1515 and the right gearing. Good luck!!!!!

[cmac]

"I got them from TC Models."[/QUOTE]

I just went to their web site and they have a clone center "slipperential"
NOT COOL AT ALL!!!!! All the parts look like a knock off of Mike's. They even call it by the same name.

[Revorocks]

Originally Posted by ZippyBasher

Subscribed... Good Job so far man. You definatley have a great plan for going about this...

I think the 1717 is a good choice as well because it can probably take close to a 1:1 ratio on the pinion/spur, with the GRP tires being so light it will run fine. Probably giving you more attempts at 100+ before it heats up too much as well. Just gotta run some extra voltage... The GRPs are just great for the speed runs too!

Thanks!

That's good to know about the GRP's, and yes I should be able to gear this motor to the moon :P
As it stands I'm looking at a 36T 'spur', but my pinion is a 30T, and 30/36 only allows for 99mph top speed on 6S, which is not what i'm after.
my only choice is to get a larger pinion made £25 :( , and have a smaller spur made, so I can run around 34/32 or higher. That gives 126mph calculated top speed, which is more what I'm after. It's just annoying having to spend £50 on just two gears!

Originally Posted by cmac

I just picked up a set of those tires from Amain for my Losi 8ight. I might try to do something similar but with the 1515 and the right gearing. Good luck!!!!!

Thanks :D
100mph should be achievable with a 1515, after theres that 91mph E-Revo, an he was running a 1515 (2700kv version), so the 2200kv should manage just fine.

Originally Posted by cmac

I just went to their web site and they have a clone center "slipperential"
NOT COOL AT ALL!!!!! All the parts look like a knock off of Mike's. They even call it by the same name.

That is a shame, Chinese are copying EVERYTHING these days

[Revorocks]

Update time:

MMM wasn't up to the task I decided, so that got sold and replaced with a Mamba XL2 :D



[IMG]http://dl.dropbox.com/u/327064/Revo/Hyper%207/Mamba%20XL/Stuff%20020.JPG
[/IMG]





Did a mock up with 7S of LiPos, will be running up to 8S for the fastest runs.





The third pack will be held in with velcro lol, I know it's rough but it works.
All the wires are to be shortened eventually. Running 8mm bullets.



Forgot to mention, I have the GRPs now! Very sticky tyres.

With 7S it's very heavy, so will put some harder springs on there.

[Revorocks]

Designed a plate to mount the Mamba XL2 on the centre diff.
It's currently being machined by Dejan.



Now for the shell, managed to get hold of a JConcepts Illuzions Hyper 8 Shell, there are very few of these left as they are discontinued.

Cut it out and masked it. Man a Dremel is PRICELESS in shell preparation, all of my bad cuts made perfect with the sanding drum.







After masking, did all the cleaning and heating of the cans for optimal spraying and put on 4-5 coats of each paint.








Applied some decals, not too many as I like to keep things simple.
Less is more :)