CRT.5 RCM Ext chassis and othe Q's

[Sammus]

Alright, so my e-revo is nearing half completion, so naturally it's time to start thinking of another project :P
Alright, part 1) I can't figure out myself stems from this:
I have 2 3s packs (4000mah 20C), currently I run them in my rustler (MM 9L) and will run them in series in my revo (turnigy sentilon 100A HV, 11XL). so naturally I'll want to use them in my crt.5 conversion too (just the single 3s packs, no crazy power goin on here!). So now for the actual question what are the longest batteries you can fit in Mike's chassis using the battery bar etc it comes with? I think mine is about 150mm long (don't have it handy to measure).

2) What will require more grunt out of my extended CRT.5 and my rustler? I'm thinking of either buying a velineon or sidewinder 4600 combo - so even though I could figure this out myself when the time comes, which would be better suited to what do you think? (out of veli3500/sidewinder4600 and MM+9L).

and 3), I've heard of a lot of people using 1/10 2.2 rims on their CRT.5's - mainly nitro rustler rears though. Does this mean my millions of e-rustler rears can be used on my CRT too? or will the offset on the e-version be too narrow?

edit: oh and while I'm pickin all your brains, whats so good about that kyosho spur that everyone loves using?

Cheers

Sam

edit2: just realised I can get the motor mount on its own... Anyone got any ideas how big of a battery will fit on it if I fashion up my own tray? Cheers

[Arct1k]

The maxamps 5000s fit fine on a stock chassis... the 9L will give you more torque than a MM.

I'd just pick up a sidewinder ESC or just steal the combo from the rustler - you won't use it much after the CRT.5 anyway.

2.2 works fine - personally I like the traxxas 2.8s. I think for body clearance I think you need the offset - so you can still use the tires just need to swap them to front wheels...

[Sammus]

Cool cheers. Any tips on de gluing tires? I've been wanting to swap all my rustler rears onto front rims for a while so I could do the nitro rustler rear arm/toe in mod.

[Arct1k]

In a saucepan with rolling boiling water for 10-15 mins a side!

Don't let it boil dry or you wife will get annoyed! trust me i know!

[GO-RIDE.com]

Originally Posted by Sammus

1)So now for the actual question what are the longest batteries you can fit in Mike's chassis using the battery bar etc it comes with? I think mine is about 150mm long (don't have it handy to measure).

Ans: I meassured my RCM Ext chassis and 150mm looks good with the stock hold down, but you will need to make your own strap. I cut one from some left over CF, but even a Losi XXX-T strap with an extra hole drilled would work.

2) What will require more grunt out of my extended CRT.5 and my rustler? I'm thinking of either buying a velineon or sidewinder 4600 combo - so even though I could figure this out myself when the time comes, which would be better suited to what do you think? (out of veli3500/sidewinder4600 and MM+9L).

Ans: I'd guess the CRT.5 will require more grunt with the 4wd system and a bit more weight than a Rusty. However, I'm sure the crt.5 can take more power. With its 3 diff and 4wd setup you can run a lot of power through it without wheeling over. Some users have had heat issues with the MM/4600. The MM/8or9L seems to be a safer bet.

and 3), I've heard of a lot of people using 1/10 2.2 rims on their CRT.5's - mainly nitro rustler rears though. Does this mean my millions of e-rustler rears can be used on my CRT too? or will the offset on the e-version be too narrow?

Ans: For bashing or rough loose tracks the 2.2 truck wheels are the way to go. But for tracks with larger technical jumps then the smaller stock wheels work better. On bigger jumps that require throttle and brake in the air to land correctly the 2.2 truck tires are difficult to control. I also break more parts when running the 2.2 truck tires. More weight and leverage.

edit: oh and while I'm pickin all your brains, whats so good about that kyosho spur that everyone loves using?

Ans: If you are willing to go through the hassle of making the kyosho spur work it is quieter than the mod1 and does not require hardened steel pinions. However, I've been using hardened steel pinions (available on RCM) for months and they show very little wear. At only $10 - $12 each, it doesn't seem worth it to go through the kyosho hassle.
Cheers

Sam

edit2: just realised I can get the motor mount on its own... Anyone got any ideas how big of a battery will fit on it if I fashion up my own tray? Cheers

Ans: The stock chassis is 40mm smaller, but not all of that space is lost because the RCM battery mount posts take up some space on the Ext chassis.

Here's the bottom line for me and a few others I've seen. In the CRT.5 lighter is better unless all you want to do is make videos of your car flipping over backwards or making speed runs on the street. If you want a car that will run with a 10th scale wheeler (very capable cars) then you need to keep it light and keep all the parts on the chassis. Long batts require you to mount items above the chassis and throw off the balance. Mike's intention of using 100mm long maxamps packs works very well for balance and handling. Plus the Maxamps packs in that size are their only 20C pack. Very powerfull for the weight.

[neweuser]

Originally Posted by GO-RIDE.com

Plus the Maxamps packs in that size are their only 20C pack. Very powerfull for the weight.

Letme see if i understand? That is the only pack they have that is rated 20c? If that is what you are saying, I would have to disagree.

[GO-RIDE.com]

Originally Posted by neweuser

Letme see if i understand? That is the only pack they have that is rated 20c? If that is what you are saying, I would have to disagree.

I could be wrong, but recently on the RCM maxamps forum someone asked if Maxamps was going to start making any 20C batts and they replied that they currently did, but they were the 2100/4200 model only. Maybe I misunderstood.

EDIT: I just checked the post and it was for 25C batts and they are the 4200 and 2200 that come with 25C. http://www.rc-monster.com/forum/showthread.php?t=9808

[neweuser]

If you look at their site, they sell 2s2p 20C ratings as well. I wasn't sure if you meant that particular size or all around for the rating. :) If you meant all around, most of their batts are 20C

[lincpimp]

Originally Posted by neweuser

If you look at their site, they sell 2s2p 20C ratings as well. I wasn't sure if you meant that particular size or all around for the rating. :) If you meant all around, most of their batts are 20C

You got some testing under your belt to prove the 20c statement? Not sure if all 20c batterys are created equal. My trakpower 2s 4900 packs outperform my maxamps 5000 2s packs, in top speed, runtime and power. Both are 20c and the maxamps have 100mah on the trakpower. Maybe the trakpower packs are under rated, maybe not.

Originally Posted by lincpimp

You got some testing under your belt to prove the 20c statement? Not sure if all 20c batterys are created equal. My trakpower 2s 4900 packs outperform my maxamps 5000 2s packs, in top speed, runtime and power. Both are 20c and the maxamps have 100mah on the trakpower. Maybe the trakpower packs are under rated, maybe not.

trakPowers are 25C

If you talk to people at fp/tp the cells are the same in the new packs, they do alot of testing, and the cells would do 25C easy, so they just moved the rating up

So yes, they were under rated..

[lincpimp]

Originally Posted by BlackedOutREVO

trakPowers are 25C

If you talk to people at fp/tp the cells are the same in the new packs, they do alot of testing, and the cells would do 25C easy, so they just moved the rating up

So yes, they were under rated..

Good to know, the rep I spoke to did not tell me that. I guess that is why the old and new packs appear to be identical in size and weight.

Still not too sure about the 20c rating of some of maxamps cells, especially the 3000 cells. Those cells only seem to be good for 45-50amps continuous before they heat up excessively or puff!

They de-rated the 10000 cells to a 10c rating from a 15c rating. I can say from experience that the 10000 cells we never 15c, not even on a good day.

Originally Posted by lincpimp

Good to know, the rep I spoke to did not tell me that. I guess that is why the old and new packs appear to be identical in size and weight.

Still not too sure about the 20c rating of some of maxamps cells, especially the 3000 cells. Those cells only seem to be good for 45-50amps continuous before they heat up excessively or puff!

They de-rated the 10000 cells to a 10c rating from a 15c rating. I can say from experience that the 10000 cells we never 15c, not even on a good day.

Max amps are more 15-17C really.... From all the graphs I have seen, they dont do much better, maybe in a tyco, but with real BL power, they sure dont hold a 20C

[Sammus]

So how much leeway do you have on the rcm chassis? I was looking at some zippy-r packs that area 2200mah 21C and 109mm long. Either that or regular zippy 2100 25C that's 100mm long.

[lincpimp]

Originally Posted by Sammus

So how much leeway do you have on the rcm chassis? I was looking at some zippy-r packs that area 2200mah 21C and 109mm long. Either that or regular zippy 2100 25C that's 100mm long.

You have plenty of leeway on the battery size. The tray area can accomodate a long battery, but not sure if the included strap can handle the 110 mm long battery. I can measure the strap in a few hours and let you know its length.

Heres a shot of the battery area and strap:

[Sammus]

Originally Posted by lincpimp

You have plenty of leeway on the battery size. The tray area can accomodate a long battery, but not sure if the included strap can handle the 110 mm long battery. I can measure the strap in a few hours and let you know its length.

That would be cool thanks.