RC Monster MBX6 Conv Kit [Archive]

BRS

11-02-2010, 03:48 PM

After a delay in customs and an 18quid charge this came yesturday. The Kyosho spur is not part of the kit but everything else is. Bit tight only supplying one strap I thought and whats the deal with that is it suppost to go around the tray and battery, it doesnt look big enough (no provision to loop through the side of thr tray)?

I'll let you know how I get on with it, no instructions supplied not sure what the servo plate mounts on... The motor mount looks quality :D

http://www.burnnitro.co.uk/images/monsterkit.jpg

Marvin

11-02-2010, 08:08 PM

Looks nice!

Should be two straps - shoot Mike an email about it.

As far as the servo mount, you use the standard plastic blocks, then take off the stock top plate, then put the new one on (with the cross for the transponder facing outwards).

BRS

12-02-2010, 09:51 AM

Had a quick look at it last night and worked out where stuff goes. There seems to only be one slot across the bottom for the one strap but I will email him and see what he says.
The zippy Lipo fits "like a glove" but as I thought the strap is too short for this brick esk battery.
All the mount points on the tray line up perfectly with the standard holes on the chassis. Some screws are supplied in the kit but not most of them which is a bit odd either supply all or non at all I would have thought?

The RX8 mounts straight onto the pre drilled tray nicely, shame that the motor to esc sensor wire is so long...

http://www.burnnitro.co.uk/images/monsterkit2.jpg

BRS

12-02-2010, 12:51 PM

BTW the Kyosho spur looks like a non starter as the outdrive diam must be larger on the Kyosho to the Mugen and there are other significant differences.

Marvin

12-02-2010, 03:13 PM

Hmm, I'm not too keen on the one strap, but it doesn't look like it could mount anywhere else easily.

Any normal sensor wire will fit the RX8 and you can get different length ones.

I think he supplies screws that are required if you include the ones you remove from the chassis. You are right though, all of them would be better.

BRS

21-02-2010, 09:21 PM

Marvin

21-02-2010, 11:01 PM

Glad to see it's going well.

I always found JConcepts shells to be roomy - I used one rather than my XB808 stock shell (which had to be raised).

jasonwipf

22-02-2010, 04:01 AM

Test ran the car on tarmac this weekend....flippineck its quick!!

Looking forward to getting on the track with it...if it ever stops snowing/rainging/freezing :D

Well impressed with the RC Monster Kit and the Zippy Lipo seems great will post a couplr more pics tomorrow.

Only problem with such a large battery is it wont fit under the standard mugen shell

Ya I had that problem too. I just use a Losi 8E body. Its looks sleek and has plenty of vents for electric cooling as well. I used a smaller mount on the back shock tower (front mount from a MBX5) to get a better fit. You can get all kinds of batteries in with this body.

Yes I have my ESC mounted on my center diff, the direct air flow from the front window keeps my temps so low I do not need fans and get 5% longer run times compared to a much hotter ESC on the chassis floor. Then to compensate for 70G of ESC being so high (center of gravitywise) I use longer flatter batteries in a hyper 9E battery case or a losi battery tray that brings my 480-640G batteries 10-15mm lower than those tall brick packs. I figure bringing 75-150G 15mm lower is good compensation for my ESC being higher and I get 20Deg F lower temps due to the better aire flow vs. chassis mounted ESC where the esc is hiding behind the tall brick pack.

In the end I honestly dont notice the lower center of gravity but do notice the better run times due to lower temps :thumbsup:

Oh, BTW More and More folks over here in the states are only using 1-2 straps anyways. We all started with the 2-4 strap stuff in the beginning and if your a big time crasher you may want that or hardcase lipos. But if your a good driver and have a secure tray 1 strap works good and is fast especially if you have to do battery changes when running 20-60 minute mains with the gas guys ( thats another reason, as 1 strap with velcro body mounts gets battery changes down from 30 sec to about 15sec)

http://i127.photobucket.com/albums/p134/jasonwipf/mbx6losi.jpg
http://i127.photobucket.com/albums/p134/jasonwipf/mbx6losi3.jpg

http://i127.photobucket.com/albums/p134/jasonwipf/mbx6losi2.jpg

BRS

22-02-2010, 10:41 AM

Thanks for thin info Jason thats great to know. If you use a different tray and a lower battery isnt it possible to use the Mugen shell though or is the roof height then the prob with the esc on the diff?

Pics
http://www.burnnitro.co.uk/images/monsterkit3.jpg

http://www.burnnitro.co.uk/images/monsterkit4.jpg

http://www.burnnitro.co.uk/images/monsterkit5.jpg

jasonwipf

25-02-2010, 03:34 AM

No I have not had any problems with my RX8 on the diff with my standard body. Its close but it does work. your pics look good, unless your ESC has heating issues i might just leave it to be honest.

Only thing on your set up I might worry about is having the wire side of the pack on the front of the battery tray/car. Hard frontal accidents and hits will put alot of force on that and inside there you got delicate tab soders, a small circuit board like thing and I always fear a hard hit could mess something up inside that end vs. the other side.

BRS

25-02-2010, 10:19 AM

Until I can get out and use the thing on a track I dont really know what to expect Jason :cry: Here in the UK its done nothing but snow/rain for 3months my local club www.pdmcc.co.uk (http://www.pdmcc.co.uk) has had to cancel most of the winter rounds so far.

I'm trying to source a 8e shell but they dont seem to be available in the UK at the moment.

Good call on the battery I'll look at flipping that over for safety :thumbsup:

jasonwipf

25-02-2010, 03:21 PM

WHAT? cancel the winter rounds because of rain and SNOW! With all the man made global warming we should have plenty of warm drought ridden dry days of racing. I'm going to write Al Gore and demand he get global warming back on track! :p

BRS

01-03-2010, 10:37 AM

Ugly (as sin, but fits the massive battery under) Mugen Duracell bread van (sorry stole your idea Marvin) :D

http://www.burnnitro.co.uk/images/monsterkit6.jpg

http://www.burnnitro.co.uk/images/monsterkit7.jpg

Last lap of 20min A final I'm new to electric I thought the battery was going all I needed to do was creap round half a lap to get 3rd. In fact the grub screw had come out of the pinion and instead of harmlessly falling off it went into the mount and motor and destroyed it bending the rotor shaft DOH!!!!!!!!
http://www.burnnitro.co.uk/images/monsterkit8.jpg

http://www.burnnitro.co.uk/images/monsterkit9.jpg

http://www.burnnitro.co.uk/images/monsterkit10.jpg

http://www.burnnitro.co.uk/images/monsterkit11.jpg

steelie600

01-03-2010, 11:18 AM

arrrrggh that looks pretty horrific sam!!!!, lets hope you get it fixed asap cos it did look well your car yesterday. But atleast you know yer battery will last 20 mins, and NNRC is a power hungry track, so somewhere like Stoke or Preston you should easily do 20 mins with power to spare

Marvin

01-03-2010, 01:29 PM

Woah, that does look nasty actually. It's always come off the other way for me...

How dare you nick my bodyshell idea - that was classic - the first! :cry:

BRS

01-03-2010, 01:34 PM

Must admitt it was brilliant fun to drive Kev...I'm hooked

Switch on ..... job done :D

Marvin

01-03-2010, 03:34 PM

Might have to change that avatar...

Glad you like it.

BRS

04-03-2010, 09:16 AM

Might have to change that avatar...

Glad you like it.
Yeah a burn Amps might have to be made :D

One thing I did notice with the electric conversion over nitro is the brakes, I'm used to having superb brakes setup bias just as I want. With ESC brakes its a different story, I usualy have my mechanical brakes setup so I can stop the car very quickly in the first 1/4 of the stick movement. With the ESC brakes I found it difficult to move the stick so far again to stop the car. Also with running the Mugen underdriven rear gearing the brakes applied through the drive train made the rear bias too much as the back wheels go slower than the front with that gearing.

When I initialy setup the ESC can I pull the stick back only half of the travel to trick it into making the brakes work faster? And what will happen if I go beyond that half way point? Or should I set a low end point on the brake, set the ESC then increase the end point to achieve the same?

Marvin

04-03-2010, 02:29 PM

You can tweak the brake strength settings, from what I recall (you have my old ESC after all) they are at about 25% strength. Stick it up in increments of 10% until you are at a 'good setting'.

BRS

04-03-2010, 02:59 PM

I plugged in the hotwire before that meeting Marv and it was 65% I upped it to 75%. I dont think its the brake strength thats the problem more the stick movement required to make the brakes work. Its something I've picked up from how David Crompton sets his brakes up, like maximum brakes at only a 1/4 stick travel. Theres no real need to have to move the stick all the way it just takes longer. You have to know what your doing though as to do this you set the end point so that if you use full stick you can damage the servo/horn/radio tray:eh?:

I'll try a few different things and see what works..

Marvin

04-03-2010, 03:12 PM

Oh right. I use a wheel where the brake throw is only half the throttle anyway (so 50% brake, 100% throttle), and I have my brakes set up to about 30% brake force. It's good enough for me, though if you're coming from Nitro I understand how that may be different.

Can't you change the location of the throttle stick so it always faces slightly downwards anyway? (Making the throttle throw longer than the brake).

BRS

04-03-2010, 03:23 PM

Battle_axe

04-03-2010, 05:33 PM

There is a 60/40 switch on my throttle stick but all that would do would be to make the throttle travel unnecessarily long Marv. Compared to Nitro the electric is so controllable I'd end up having to dial in positive expo to make it feel like it goes right.

I'll try going max brakes and then upping the end point and see how it is.
how about setting the endpoint on the rear to like 30% then set up the esc then put it back to 100% that would give you full breaks at a really short throw of the stick

BRS

04-03-2010, 06:44 PM

Yeah I mentioned that earlier, I'm going to give that a try;)

jasonwipf

05-03-2010, 06:25 AM

Marvin

05-03-2010, 07:20 AM

Ouch that pinion looks bad. an elite rc mount has the pinion out the other way and woulda fell off in a grub nut loosen, plus the extra bearing in the motor mount woulda absorbed alot of the stress you undoubtedly put on that front bearing. They can and will send you a rotor no problem but I would be concerned that front bearing is chewed up alot of its functional life with that sorta of trauma.

Not necessarily - I've often had pinions that way round, but they have always fallen off forwards. I guess it is just luck.

That's a good point to raise actually, you will probably need a new front bearing in there - the sideways load of the rotor bending would probably be enough to destroy it.

BRS

05-03-2010, 02:46 PM

Theres no way that bearing will come off anyway its that bent. I had ordered 2 fronts and 2 rears from rcbearings.co.uk when I got the motor as the rear was nosiey so no biggy.

jasonwipf

05-03-2010, 04:03 PM

Not necessarily - I've often had pinions that way round, but they have always fallen off forwards. I guess it is just luck.

No, what I mean is that with increased mass due to the slider and extra bearing in an elitercd mount the pinion has no space to fall inward like that.

Marvin

05-03-2010, 07:04 PM

Oh I see.

BRS

06-03-2010, 08:11 PM

The Esc wont let you setup with the brake anything less than 100% epa selected....at least not on my radio (Futaba 3VCS)

I've dialed in 90% brake strength and upped to 120% epa and see how that goes....

Marvin

06-03-2010, 09:40 PM

Worth a go!

BRS

07-03-2010, 06:36 PM

Brakes were a lot better today with 100% strength and 120epa not quite what I'm used too but very driveable.

First time on my home track of Pendle (big dirt track) today, cars ballistic. I was going tripple - single on a section thats only ever been double doubled, was a bit scary...

I weighed my Mugen against Crompy's Mugen, 3.8kg vs 3.3kg (no fuel) that 1/2 a kilo seems to hinder the car a bit over the bumps.

I'm going to try a couple of smaller zippys 5S 2650mah 40c see how they are at $40 each not too bad from Hobbycity.com 250gram lighter than the current 5000mah

Marvin what motor / esc temps should I be looking to see? After a 20min run today the motor was 60c and the esc 55c....
Thanks again for the loan of the rotor its been an ace day in the sun!

Marvin

08-03-2010, 08:13 AM

180°F is the most you'll look at for motor temps -> 60°C is 140°F, so you're fine there.

ESC temps are fine as well.

Glad everything went ok, but you're finding out what I did last season - big batteries reduce handling.

BRS

15-03-2010, 02:19 PM

Raced at Pendle yesturday with the MBX6e after the practise and testing there last sunday. Track was perfect condition and it was a top day. I'd plugged into the laptop day before and changed the throttle profile from linear to the next one up a more aggressive one. Mistake... it was too aggressive I ended up dialing in 20% neg expo on the radio to get some control back as I was fighting the rear out the turns.
After using what seemed like about 250mah/min I turned down the throttle end point to 90% as it was plenty quick enough and ran some more qualys. The smaller batteries I ordered havent arrived yet so I was looking to try and do 20min final on the 5S 5000mah Zippy pack.

I qualied 2nd behind Crompy and just rolled up to the grid no warm up laps. After thinking I couldnt make the distance I was able to do 4 extra laps at the end and still pull in with juice left. What I have to get used to is the difference in power from the start of the race to the end. After about 8min the power noticably drops of and you have to use alot more stick to achieve the same results. I thought after 10min I would never finish but it was just this drop off in performance as the voltage drops I guess. Fully charged Lipo = 22volt x 1700kv = 35700rpm as it gets towards fully flat that will drop a good 6000rpm. I charged the pack later and it took 4777mah so plenty including the warm down laps. Motor was 60c and Esc 65c at the end will no major ventilation holes in the body...

Anyway finished in 2nd behind Crompy results are here if you are interested
http://www.pdmcc.co.uk/current-season/

Also its a strange feeling driving 20min without stopping for fuel :D

BRS

16-03-2010, 11:04 AM

2 x shiny Zippy 5S 2650mah Lipos came yesturday from Hobbycity...Zippy seem to have upgraded their specs from the 5000mah I bought. Not got any decent scales but they seem half the weight of the 5000mah and the standard mugen shell will fit over these no worries...

5S 2650mah
40C
5C charge rate

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=9949

BRS

22-03-2010, 11:26 AM

Raced again yesturday and for the first time with the lighter batteries.

I dont understand how its possible but the car seemed to have less power with the smaller batteries? The batteries are a higher rating 40c over 30c so its weird

5000mah Zippy 5S 30C Vs 2650mah Zippy 5S 40C can that be explained or did I imagine it? I was on Astro after being on dirt previously but I through the 5000mah pack in for the final as I had no one to change batteries at a pit stop and it def seemed quicker and I posted faster lap times?

Hmm

Dunc

22-03-2010, 11:41 AM

The current available from the batteries is the product of the C-rating and capacity (in Ah not mAh):

30 x 5 = 150A
40 x 2.65 = 106A

So the smaller capacity pack will feel more sluggish.

I think that's right!

Raced again yesturday and for the first time with the lighter batteries.

I dont understand how its possible but the car seemed to have less power with the smaller batteries? The batteries are a higher rating 40c over 30c so its weird

5000mah Zippy 5S 30C Vs 2650mah Zippy 5S 40C can that be explained or did I imagine it? I was on Astro after being on dirt previously but I through the 5000mah pack in for the final as I had no one to change batteries at a pit stop and it def seemed quicker and I posted faster lap times?

Hmm

Marvin

22-03-2010, 11:56 AM

Yes, exactly right. You need both capacity and discharge with batteries. It does mean you can get away with lesser discharge rated batteries if you have a high capacity.

steelie600

22-03-2010, 12:17 PM

aye if you had a 40c "brick" sam it will be mentally fast!!!!!

5amp x 40c = 200 amp discharge!!!!!!! you can weld 1/4 inch steel plate with a lot less!!!!

BRS

22-03-2010, 03:55 PM

Haha well I never I'm not going daft then, thanks!

Now theres a though Kev :D

jasonwipf

27-03-2010, 06:41 AM

We have noticed longer run times with lighter packs, sometimes worse if combined with too low a gear cuz of excess wheel spin that happens when you got alot of toque and not alot of weight (depends on your traction) but overall many of us are going lower C rating with little detriment since the power is sufficient and it get cooler running temps.

lgbzone

30-03-2010, 06:46 PM

The current available from the batteries is the product of the C-rating and capacity (in Ah not mAh):

30 x 5 = 150A
40 x 2.65 = 106A

So the smaller capacity pack will feel more sluggish.

I think that's right!

Hi

How do you calculate it if you are using two batteries? I assume the C stays the same but do you double the capacity?

Cheers

lambchops

30-03-2010, 08:08 PM

Didnt see it in your post but what KV motor are you running? Interested as im tempted with a 1700kv tekin motor (secondhand) but am worried the KV could be a little low. Nice conversion BTW!!

BRS

30-03-2010, 08:54 PM

Hi

How do you calculate it if you are using two batteries? I assume the C stays the same but do you double the capacity?

Cheers

No you still have the same capacity just more cells/voltage

BRS

30-03-2010, 08:55 PM

Didnt see it in your post but what KV motor are you running? Interested as im tempted with a 1700kv tekin motor (secondhand) but am worried the KV could be a little low. Nice conversion BTW!!

Its 1700Kv Lambchops on 5S its seriously fast I was pulling away from Crompys RB B10 on the straight at pendle :woot:

PM for you mate

Battle_axe

30-03-2010, 11:58 PM

No you still have the same capacity just more cells/voltage
if in paralel the C rating is doubled if using identical packs

if in series then the C stays the same but the voltage doubles if using identical packs

BRS

31-03-2010, 11:40 AM

if in paralel the C rating is doubled if using identical packs

if in series then the C stays the same but the voltage doubles if using identical packs

Yeah that as well , maybe tell us what packs you have and how you run them for a proper answer

lgbzone

31-03-2010, 05:16 PM

Thanks guys :thumbsup:

I think i've got it now.

I have a couple of pairs of 11.1v 3700 25c/50c, and a pair of 7.4v 4600 45c batteries, I use them in series therefore have the following configurations;

2*11.1v 3700 25c/50c (constant/burst)
Volts = 22.2
Capacity = 3700
Current = 92.5/185

2*7.4v 4600 45c
Volts = 14.8
Capacity = 4600
Current = 207

I think that's right.

Did you say earlier that you got 20 minutes racing from a 5S 5000 battery, how would a different Kv motor effect run time? (if at all), i understand driving style and the track would play a part, but do you reckon it would be reasonable for me to expect similar run times from 5S 5000 if mine has a 2200Kv motor?

thanks again

Lee

moogen

14-05-2010, 08:18 PM

hi guys, got a mamba 2650kv to be used in my 1/8th mbx6 buggy conversion.

I understand a 4s is abit too much. or is it not?

what lipo would you all recommend

thanking in advance

lambchops

14-05-2010, 10:34 PM

Thats just what I run in mine Chris, its rapid but still does 20 mins with the zippy 4c 5000 40C batterys. I would defo recommend 4 cell 3 wont be enough

moogen

17-05-2010, 04:56 PM

Thats just what I run in mine Chris, its rapid but still does 20 mins with the zippy 4c 5000 40C batterys. I would defo recommend 4 cell 3 wont be enough

cheers john, apparently 4s x 26540 v , is around 40,000rm , which will be a bat from hell. i been told to go for 3s lipo.... oh well more money to be spent then

lambchops

18-05-2010, 08:14 AM

Yeah it is fast on 4 cells but not too much so. I ran my leccy in the nitro A main at clanfield Sunday and managed 18 mins with this combo on the flightmax 5000 four cell battery. I was third until the battery ran out and the motor and battery were only slightly warm. The speed controller wasnt even warm!!

I was only using about half throttle most of the time with the odd full blast on the main striaght when I had a nitro car to show off too besides me haha

jasonwipf

18-05-2010, 06:02 PM

Ya with that combo we have guys run both 3 cell and 4cell. I would recommend 4 cell for these reasons:

1. when you want more speed its there
2. if you dont want that speed just turn down your travel to 75-85% of full and it behaves like a 3cell giving your motor lower voltages (best of both worlds)
3. If you change motors later and go to lower kv then your already set with 4cell batteries and dont have to stock pile both types (money waster)
4. 4cell will run cooler than your 3cell which will be more critical in the summer months to come

moogen

18-05-2010, 06:30 PM

thanks jason,

finally some one with proper advice. by the way i have the hobby wng esc, how do i turn the accelaration down?

lambchops

18-05-2010, 08:35 PM

You mean my advise wasnt proper, how dare you!! :D

thanks jason,

finally some one with proper advice. by the way i have the hobby wng esc, how do i turn the accelaration down?

jasonwipf

19-05-2010, 03:45 AM

I turn down my travel at the controller. I soften my acceleration by increasing my exponential. Try those 2 before messing with the esc options.

BRS

20-05-2010, 12:39 PM

Looking at selling my MBX6 electric conversion gear / lipos / ESC&motor&hotwire as featured in this thread.

PM me if you are interested

RC Monster MBX6 conversion kit (std lipo tray size) Used at 3 meetings
Flightmax 5S 5000mah 30C x 1 (used at 3 meetings)
Flightmax 5S 2650mah 40C x 2 (used at one meeting)
Tekin RX8 ESC (Used to be Marvins)
Tekin Hotwire
Tekin T8 1700Kv (Brand new rotor and bearings raced once)