Possible Hyper 7/Novak conversion

[lincpimp]

Just throwing out some ideas here, let me kno what you think!

So I have a HYper 7 roller sitting here, brand new and waiting for some brushless power. I also have a mm, ccbec, 2 trakpower lipos, and all the radio gear. Instead of the usual feigao motor, I would like to try the novah hv6.5 motor. Kv is a bit high, but on 4s it tops out around 45k rpm, which should be ok as the novak motors are made well. Gearing would be 11/46, so slightly under 40mph. I would also buy novaks mount kit, as it sounds interesting.

Any thoughts on this? The buggy should be reasonably light and novak's site says that the supply a pair of battery trays. I will wait to se the actual layout before I buy it though. I would also do the 5mm shaft upgrade, as people seem to snap the 1/8 shafts off.

Another issue is how well will the MM run the noavk motor? I know that the recent firmware updates make it a better esc. Will my combo of low gearing and light weight (hopefully!) help this?

[pipeous]

As far as buggies go, I thought the H7 was a tad on the heavier side.

[lincpimp]

You may be correct, I have played with a few differnt buggies, but most of them were lower end so they all seemed very similar. I am sure that a rc8 or 8ight would be lighter.

[Serum]

The thing that worries me about these conversion is that they mount the motor on the wrong side of the diff; they diff has off-set from the center, away from the motor. Since electric motors use less space than nitro motors, and batteries take more room than the nitro tank, it's better for the weight ballance to put the motor on the opposite side.

I wouldn't take the 4.5, i would take the 6.5, since the gearing ratio is pretty tight on a buggy. The torque on the 6.5 would be slightly higher than the 4.5 since it has got more windings.

And get a hvmaxx with a 5mm shaft instead the normal 3.2; i heard a lot of people wasted the 3.2mm shaft on their rather 'direct drive' buggies. 5mm is the way to go.

If you have got enough room to mount the batteries, i wouldn't worry about the placement of the motor, since it's a convenience conersion.. I like the direct drop-in bolt on idea in general. It just needs some tinkering to get it worked out perfect. The nitro chassis isn't an ideal template to start with. (unless you move parts around)

[lincpimp]

Now, more questions, I have a plett maximum and it has similar ratings to the hv6.5. I may try it out, but the 1.8 sahft does worry me a bit. I will use a plastic spur, and will not be jumping the buggy. Whatcha think!

[DrKnow65]

I'm interested as I've got a hyper7 PBS just waiting for the MMM. Would be cool to see what you come up with, what works and what doesn't...

[lincpimp]

Well, since I have the rcm motor mount for the hyper 7, I was thinking about picking up the rc product designs battery trays. This would give me a good mount for my trakpower packs and kep the cg low. Plus I like the bolt in approach.

I am a bit worries about the 1.8 shaft on the plett, not sure how good their service is. I guess if I broke it I would get them to replace it with a 5mm shaft. I also have a hacker c50 max motor that I could use. That may be the ticket, as it was cheap and I really would like to see how a low geared high speed motor works compared to the higher geared lower speed motors that I am used to. We shall see. ime to order some 1/8 buggy badlands!

[t-maxxracer32]

hyper 7 pbs

pbs?

[gixxer]

pivot ball suspension, like how the e-maxx, t-maxx suspensions are.

[lincpimp]

Ok, did some work on it earlier. No pics as the camera is dead and I do not have any other aas.

I installed the rcm motor mount and the hacker c50 maxx motor. Smallest pinion that will fit is a 13t. This is with the motor slid all the way to the end of the mount slots. There is also about 2mm between the motor and the rear center diff output, so that will be the gearing it gets! I replaced the steel spur with a kyosho 46t spur. Fits nicely, but it may need another diff gasket or two to get the front center diff bearing completely in the front bulk.

I also ordered a set of the rc product designs battery trays for the hyper 7. They look nice and give me a premade solution to running the 2 trakpower lipos. Should keep the cg low, but the batts will be further out away from the center line. We shall see how this affects handling.

The trays look good in pics, I will most likely need to mod the motor mount, as it looks to be in the way of the tray. No worries, I will just trim the end off and radius what is left to clear the tray and be asthetically pleasing.

Only one issue, the battery trays are 70 bucks per side inc shipping. Kind of a smack to the nuts if you ask me. The good thing is that I just sold a few motors and a bunch of junk on ebay, so the money was there for these. They had better be nice, that is all I can say.

I plan to use a MM for esc duties, but I also have a mgm 90amp 4cell esc lying around. I will mount it directly opposite to the motor. We shall see. I really like the MM and have a spare now that the xxx-cr has a sidewinder in it. Not sure on the steering servo yet, need a 130oz or better and would prefer a digital. Time to find a good servo!

[gixxer]

Originally Posted by lincpimp

Only one issue, the battery trays are 70 bucks per side inc shipping. Kind of a smack to the nuts if you ask me.

ouch and I thought it was bad when I bought one of there earlier designed trays. I think I paid $60, but I only needed one so it was okay.

[lincpimp]

Ouch is right!

At least the rest of the equip was cheap. 100 bucks for the MM, 50 bucks for the motor, lipos were traded for some labor, as was the ccbec. I think I paid 170 for the hyper 7 roller, brnad new. Motor mount was 40 IIRC, And the rest was just hanging around.

Crap, I paid almost as much for the trays as I did for the mm AND the motor, and not far off the roller. Damn, at least it should look good when I am done.

[lincpimp]

Have not received the trays yet, but I did some work to the MM.

I decided to add a novak cap the the board where the main power leads attach. I left about 1.5 inches of wire on the cap so that i could mount it out of the way.

While i had the plastic case off I had a good look at the MM. Turns out that the heatsink was barely glued on! I removed it and the thermal glue residue. I then filed the bottom flat with a file and used some arctic silver thermal epoxy to hold it together. I used very little and made sure that I coversed the entire surface of the fets with a thin coating. It looks good now and the only light that can be seen is between the rows of fets from each end. I feel better that the heatsink is properly attached!

I will have to check my other MM escs and see how they are!

[lincpimp]

Got the battery trays in today and did some work to the motor mount.

I had to flip the motor mount upside down so that the motor would sit where the nitro engine would be. This was due to the fact that the battery trays overlap the chassis toward the center. Since the diff is offset to one side, the motor fit nicely on the other side. I had to cut a portion of the motor mount off and enlarge the thread on the bottom from m3 to m4. The diff sits higher now, and I had to mod the existing front bulk to get the bearing carrier holes level for the center diff.

I will have to make a new srevo tray and upper plate for the center diff bulks. I have some cf sheet that I will use for that. Looks like the MM will be across from the motor and the receiver will be across from the steering servo.

The battery trays did not come with the straps, those are emaxx battery straps. The al stap mounts were included, but no bolts or screws came with the trays. I eventually found that the small allen head screws that come with the associated battery cups had the correct thread (sae) and they have a hole drilled thru the head to accept a body clip to retain the straps. It would be nice if RC Product Designs would have included a note about that.

I need to scare up some diff gaskets, as it is too tight with the Kyosho plastic gear and the spider gears are binding. That should also space the center diff correctly in the bulks, as there is a bit of play right now.

Hopefully I can get those parts together quickly and finish this build!

Heres the pics:

[phildogg]

looking good bro.
phil