Ideas for a BL CRT.5

[crazyjr]

I been playing with my E-GT for a while, while its fun it still has the same problem that plagues all modern stadium trucks, 2WD. I have been look at my CRT.5 and thinking what combo would work best, I have come up with two choices:

Lehner basic XL1200/ quark 80 and 4 or 5s Lipo
the pro's;
1. Efficient setup running Flight power 2500 5s Lipo, never runs hot and never pulled over 40 amps on eagletree.
2. Strong setup without being weighty.
not many cons, I love this setup. The only one is needing a UBEC (not really bad, but added stuff to go wrong)

Neu 1107 2y (3400KV)/quark80 on 3 or 4s lipo's
pro's
1. much smaller and equally powerful motor, Possibly able to run 3s on BEC.

cons
1. need new batteries, Dont have flightpowers in 3s or 4s in a 2500 size
2. need adapter to fit the 540 holes in RC-Monster motor mount
3.not really sure if the 1107 can pull the CRT.5 without stressing out

Not that the current crop of E-CRT.5's are not impressive, but i think they are too heavy and too much power (5,000 mah lipo's on some and fegaio L cans, pletty maxximum and lehner 1920's) I understand the quest for power, but thats big block chevy in a morris mini type of thing. I think a smaller lighter setup would be just as good and possibly better for racing. I may also look into the extended chassis's but only if i think i need it for stability

I am leaning towards the basic XL1200/quark on 5S 2500 flightpowers, but would like other opinions

[steve050773]

I went with a Neu 1506 @ 3600kv with 2s or 3s. Not sure I'd want to deal with the 1107 and its odd bolt pattern. The 1506 is shorter than a mamba but with a greater diameter.

How big is the Basic XL - it has to be similar if not a little bigger than a 1920.. I just don't picture it fitting into a smaller lighter solution.

[BP-Revo]

I'd go for choice 1...

I run a 1930/7 on 3S FlightPower 3700's, and while it has a tremendous amount of power, its easily controllable and not just "stupid." Also, I can just throw in my 2S FlightPower 4500's and turn the power down quite significantly (though it still has plenty at that point, and thats running with very low gearing).

I also personally agree with the the whole "lighter and less of a motor = same power as a big motor and heavy setup," but their comes a point when things get too light...and while I wish my CRT was a bit lighter at some points, the added weight really adds to stability, but doesn't seem to affect handling. On top of that, its not like what I am using is overly heavy - a 1930 isn't much more than a Mamba Max motor and the 3S 3700 pack is actually lighter than a 5S 2500mah FlightPower...

[jhautz]

only one way to find out what you like best....


Build em both and find out!

[crazyjr]

Originally Posted by jhautz

only one way to find out what you like best....


Build em both and find out!

The plan is to eventually build both, I am getting out of mini's so the 1107 would be available. One will be stock with short chassis or optional ofna chassis, and the other will be a long chassis with traxxas dish wheels (not as far offset as the rustler fronts, but not as narrow as the rustler rears)

the lehner is about the diameter of a 540 motor with a slightly shorter can.

the 1107 has a long 1/8 shaft so an adapter will not be a problem, Just need an adapter because the bolt pattern is for a Mini plate

[GO-RIDE.com]

I run my E-CRT.5 at a high quality indoor track and it sucks a new 4800 2s lipo dry in about 20 min. This track is pretty tight, so the back straight is the only full throttle area, but it is also high traction so you can use a good bit of throttle everywhere. My set up is a Novak GTB & 6.5 (5900kv) with Panther Switch 2.2 truck tires geared 46/12-13.

You definitely don't need an XL motor in this vehicle, my little Novak pushes the crt.5 around the track very fast and it doesn't get hot. I run a fan on the esc (probably doesn't need it), and don't even have a heat sink on the motor. Something in a L can around 3000-3200 kv on 3S would probably be ideal for this car.

Let us know what you decide.

[crazyjr]

I am probably going to start with the basic XL1200/quark 80 and my 5s 2500 lipo. I know that that sounds a bit too much, but i can gear to what i want speed wise and it will not get hot. With this setup, I can run about 30 minutes to 40 minutes, in my E-GT between charges (I really don't know, because i get bored before it runs out)

[Finnster]

The 1920 is a pretty small motor too, its quite a bit smaller than the 380C/L I pulled out. Lots o power tho. :)

I have a 10 turn (3135kv) I think I'm going to move it to my new CRT .5. Did some spd runs the other day w/ my heavy beefed up Rustler to test it and it was doing 53 on the radar with M2Ks on, and w/ me letting off the gas to pull the radar gun out. I wasn't even overgearing it @20/87. Dead cold as well. Think I was hitting ~55, but the day ended early when I hit WOT too early and backflipped it @ ~40mph. Oh well, that tranny case was getting loose anyway.

I'm also thinking about using 4S A123 as a saddle pack in the rear, or else getting a 3S 2500 Neu pack for it (maybe still too fast tho.) The 5s is a pretty chunky pack, and quite a bit heavier than my 4S A123s would be. At the very worst the LMT can be rewired as a 17T ~1800kv motor. I initially planed to use my 4S 3200 pack in it, but once I put it upto the chassis I realized just how big a batt it is.

I think you could cut the battery down quite a bit and run a little higher kv for some weight savings, unless you are looking for really long runs. Saves a Ubec too. What about a smaller quark as well?

[lincpimp]

Hey Crazy, I have run a similar sytem in my LS10 for a while. I have a maxamps 3000 5s pack and a quark 65 roadster. I am using a hacker c50 13l motor, but have a 15l to swap into it. Tons of power and great runtimes and cool equipment! Hv setups are the way to go. I could almost go down to a 2100 5s pack, or go up to 6s and gear it way down. I am slowly try to chane over to 5s and up as the benifit is very noticeable. Pack size and weight do become an issue, but there are quite a few small cells with good dimensions that can be use, plus you can always break up the pack and place them in different locations on the chassis. The crt.5 does not have much real estate, but I am sure that you can find a way!

lol I am going to buy a 1509 1Y I think... 3600KV is perfect for me, I can use 2, and 3s if I get one....

But the light set up sounds nice, I just wonder how it will drive light, compared to the heavy one

[crazyjr]

Thanks for the thoughts guys, I think the pack will not be as heavy as some other packs. I remember weighing all my 4s and 5s setups and the 2500 5S was about 340 grams, the 6 cell 4.4k NIMH is 430grams for comparison. I have even thought of doing a quark 33 procar on the neu, to see if it can really work and survive. I figure the 5s will work great with the basic XL1200/quark and that will be the easy project. The neu motor might be a bit different, it will be new territory and will be interesting to see how it works