BL system for a crt.5 on 2s
 

What is a good system for a crt.5 using a maxamps 2s2p 8000 lipo?. I have two of these packs so i would like to stick with 2s & not have to buy a 3s pack. I will be keeping the stock chassis .

Personally, I would just run a MM Motor (5700) or a L can motor with an MM ESC, unless you can dish out the money for a Neu 1509 (then I would do that).

perhaps a novak Hvmaxx 4.5.

BP-REVO
I like the MM combo. so would the 5700 setup be the best for 2s also if i was to use a L motor on 2s which one would be the best to get ?. What would be a good start for the gearing ?.

Rene i thought about the novak system. But i like the probramability of the MM system .

Just in case you are interested...

http://search.ebay.com/_W0QQsassZluv2shop530

Yup, I second using the 5700.

I just did some calculations using brian's calculator & this is what i got. I did the calculations using a 12t pinion & the MM 5700 system.


Differential Ratio: 3.25
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 46
Pinion Tooth Count: 12
Total Voltage: 7.4
Motor KV: 5700
Tire Diameter (inches): 3.25 kit bow ties
Tire Ballooning (inches): 0
Motor Current Draw: 35
Motor coil Ω: 0
Spur/Pinion Ratio: 3.83 : 1
Total Ratio: 12.45833 : 1
Tire Circumference (inches): 10.21 inches (259.34mm)
Total Motor Speed: 42180 RPM
Vehicle Speed: 32.74 MPH (52.58km/h)
Effective Speed Rate: 4.42mph/V (7.11kmh/V)
Effective KV Value: 5700
Motor Torque: 0.04 ft-lbs
Final Torque: 0.54 ft-lbs

At that speed it will probably stay cool. I would say go with a feigao 7l, it will run well with those 8k packs and you could gear for more speed than a 5700.

If i use a 7L it will take a very big pinion to get the same speed.

Ratio: 3.25
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 46
Pinion Tooth Count: 20
Total Voltage: 7.4
Motor KV: 3511
Tire Diameter (inches): 3.25 kit bow ties
Tire Ballooning (inches): 0
Motor Current Draw: 35
Motor coil Ω: 0.0059
Spur/Pinion Ratio: 2.3 : 1
Total Ratio: 7.475 : 1
Tire Circumference (inches): 10.21 inches (259.34mm)
Total Motor Speed: 25256.38 RPM
Vehicle Speed: 32.67 MPH (52.48km/h)
Effective Speed Rate: 4.41mph/V (7.09kmh/V)
Effective KV Value: 3413.02
Motor Torque: 0.07 ft-lbs
Final Torque: 0.52 ft-lbs

Which would be better & would 20t pinion fit if i decided to go with the 7L ?.


I've started my conversion by taking off all the nitro gear & cleaning the car. I have also made my battery box using kydex plastic. I will have to make a new top plate for the center diff & battery box brace. Im going to try to make it all one piece. this will also be used for mounting the ESC & RECIVER.

Well,

The feigao l can will produce more torque than the 5700 and allow for the higher gearing. You use of 2s batteries does demand a higher kv motor than is optimal. However the batteries you have are capable of 160 amps constant so it will not be too big a deal. Maybe a 6l feigao would be better. TBH you could buy the mm/5700 combo and try it out. If you do not like it, sell the 5700 motor and buy a 6l feigao. The 5700 motors sell well on ebay, so you should be able to get almost enough to buy the feigao motor. The 6l is about 4000kv, so an 18t pinion would put you at 35mph.

I too just started converting a crt.5 and I am using 1/10th scale truck tires. In my opinion they look better, will last longer and have a flat patch of rubber on the road (as opposed to the rounded buggy tires that come stock) and they are about 4" high which allows you to run a smaller pinion gear. here is the speed calc with a 2s pack and a 3600 kv neu motor:
Differential Ratio: 3.25
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 46
Pinion Tooth Count: 16
Total Voltage: 7.4
Motor KV: 3600
Tire Diameter (inches): 4
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor coil Ω: 0
Spur/Pinion Ratio: 2.88 : 1
Total Ratio: 9.34375 : 1
Tire Circumference (inches): 12.57 inches (319.19mm)
Total Motor Speed: 26640 RPM
Vehicle Speed: 33.93 MPH (54.5km/h)
Effective Speed Rate: 4.58mph/V (7.36kmh/V)
Effective KV Value: 3600

yup, a few of us use 2.2 truck tires. I have dirt works on mine right now. They are great for all terrain use. Not too good on the track though... But you can always switch back to the buggy tires for that.

I think a 5700 would be plenty fine for that application. The S can (the 5700) works fine for the smaller 1/10th scale stuff. I've run one in a T4, a B4 and I'm sure it would work fine in my ZX-5 that I'm running a 7700kv in. Something smaller like the 1/12th you are going to run it in shouldn't give you a lick of trouble. In fact, a friend of mine ran a 5700 in his .5 conversion and he was pleased. Besides, if you wanted to go really crazy you could stick a 3S in there, hehe.

Actually the mm motors have shorter magnet than the s can feigaos. My personal expereince was that my 6900 motor could not keep up on my ls10 on 2s lipo. Way too hot after a 5 min run. Just depends on the gearing. 32mph should be fine. I always gear my stuff for 40mph, cause anything less is boring.

Would a different mamba system be better or is the 5700 system the better choice ?. also do i need a bore reducer ?.

You may want to ask briang, he is using a mm 4600 on his crt.5, but he runs 3s. I am not very impressed with the mm motors. I have tested most everything including the vxl system from traxxas against my mm esc and feigao 12s (3000kv). I have not found a better sytem yet, for 3s lipo that is. I found the mm motors to heat up very quickly, but my gearing was higher than yours so there was more load on the motor. I would give the mm 5700 setup a try and if you do not like it sell the motor and buy a feigai L can, or some other type of motor. It is best to experiment to find the best combo you like, I can only give my experience, which is limited to 3s and higher. I have maybe ran 3 systems on 2s and was dissatisfied with the performance. I even run a twin traxxas titan 12t motor wild dagger on 3s lipo! Those brushed motors can handle some voltage!

Thank you :smile: I just ordered my motor mount & bore reducer.

No problem, it is hard to give advice cause everyone's driving style and intended use is different. I like really fast trucks and bash in grass and on the road. Wheelies are a requirement for me, as is top speed. I have not broken much, except maxx diffs! My driving skill has improved much since I started rc 2 years ago.

I was at work today & got to thinking. Would the traxxas venolin system be any good in my crt.5 Or is the MM a better choice ?.

On 2s the velineon will be slower than the mm. Plus the velineon esc does not have much (if any) programability. I have owned both and consider the mm esc to be very superior.

thank's again :lol:. i just saw the venolin motor is only 3500 kv. I'll just get the 570 MM system from my friend's store.

i just talked with brian g & he suggested not to use the mm motor but to use a feigo s motor. He said a 7s with a 15t pinion would be good for around 35 with the kit tires. He also said if i wanted to use truck tires that a 8s with a 14t pinion would be good. He also said these motors would not get as hot as the mm motors because they have a little more torque. So im probably gonig to get a 7s motor. what does everyone think ?.

Well if you do not want the mm motor, the feigao s can is a better choice. I have a stampede with a 12s on 3s lipo and it has run better than any other small motor I have tried. I have pitted it against the mm motors, the velineon motor and a few others. If you look I posted a thread that shows the internals of the mm motors versus the vxl motor. Both are smaller than the feigao s can.

I have a slightly used (2 runs) 7s motor here, If you want it send me a pm. Nothing wrong with it, just too high kv for me as I am going to 4s and higher systems.

Ygpm

I would like to post a couple of pics of my crt.5 conversion so far, but i dont know how. Can i email them to some one to post for me ?.

Do you have a photobucket acct?

Sign up and you can upload your photos to photobucket and then jut copy the img code and paste it in a post. The pics will show when you preview the post or submit it. It is also nice to be able to access them from any pc too!

No i dont have a account there even if i did i would'nt know how to use it. Im not very computer smart.

You can also sign up at Picasa....its free and easy.

http://picasa.google.com/

Check your pms bro

http://i11.tinypic.com/80q2f4w.jpg

http://i9.tinypic.com/7yogpqe.jpg

http://i18.tinypic.com/8e883e9.jpg


There you go :mdr:

Nice start!

Thank you i wish they were a little clearer :lol:. I think next time i'll take them in the daylight out side.

No problem

So whens the BL going to be coming?:party::na:

I bought a 7s motor from lincpimp & it's in the mail, so it should be here anyday know. My buddy is going to order my MM for me tommorow, & i al ready have the 2s2p 8000 lipo's.

Sweet

Almost there =)

Given what you have spent, it is a much better system and cheaper than the mm/motor combo. Hope you like the motor, at least I know that your batteries can keep up. You will be suprised how much power the 7s puts out. My e-jato was extremely overpowered, could wear out the rear tires in 30mins on blacktop! 4wd will be much better to harness the power!

I really have'nt spent that much. i all ready had the lipo's i use them in my crt also. I got a great deal on the motor :yipi:, & im getting my MM & at great price also.

http://i9.tinypic.com/6tf2tm1.jpg


Nice!

thank's as you can see i made a cover for my lipo pack. It is 1/16 inch thick aluminum & fits between the battery & the top of the box & is held in place by the strap. . The battery box is made from kydex & so is the esc, battery box brace & center diff brace COMBO. The esc mount & box brace & center diff brace are all one piece.

Looks great...I can't wait to see it finished. Let us know how it runs with the 7S...

Thank's & i should get the motor any day now. I ordered my MM today it will be here thursday.