My brushless Revo

[BrianG]

Originally Posted by Finnster

Lastly, I don't think the plastic is oil-impreged. Some nylon is, but this is approved for 3A sanitary/FDA usage (dairy and food contact.) It is very slippery tho, close to teflon. This is often used as machinery guardrails, slides and such.

Yeah, that's what it looked like - the stuff restaurants use as a food prep surface/cutting board. I was thinking of the Subway food prep area when I saw that.

Originally Posted by Finnster

Brian, you had bigger tires on yours w/ the 14t as well, correct?

Actually, my tires were the standard size, just heavy due to the tread design. The whole truck was heavier due to material choices, and I used 14T. My truck was a little over 14lbs with 14 GP3300 cells. I'd increase a tooth for every two pounds lighter than 14. So, if you are at 12lbs loaded, I'd try a 15T. When I went with 15T, my ESC heated up more, so it should be just about right if yours is lighter. If you had the cash, I'd say get a 15T and a 16T, but I think 15T will be just about right for that motor.

[Finnster]

Chingame! I got the 15t, its was $4 extra for a total of $16... I hope I got the right one. Now I am wishing I got that 14t as well.. Oh well. The little gear ratio proggy puts the truck at 42mph with 15/51 and 40K rpm. Sounds about right, just hope its not too high. The weight should be a bit less than your V1, but I'm not sure by how much. The NIMH batts add 2 lbs themselves. 5s lipos would be great, but I have 4 pairs of NIMH I share with the rusty, so Its really the best for me right now. I can't wait!

[BrianG]

Chingame? :032:

[Finnster]

Well I got the esc mounted, now just waiting for the gears from Mike and I should be about set. I ended up getting a 15t and a 16t.

What's the deal on BK upgrading 7720s and 9920s I keep reading about?

[squeeforever]

You can send your 7020 in for a small fee they will make it a 9920, and if you send in your 9920 they will upgrade it to a 12020, and so on and so forth...

[Mike.L]

nice revo dude!

[Finnster]

I was going to run to the LHS to pick up some parts and I wanted to stiffen the springs, esp in the rear now that it sags under the batt weight. I was going to go to tan springs in the rear, and move the greens upto the front. How does this sound? Thinking of repacking w/ 50 (or 60?) wt oil as well. What has everyone else found works well? I'm def will be going off road and taking some good 5-6ft jumps.

[HotnCold]

60 weight and try the silver 120 mm springs - ( even if your running the 90 mm rockers ) - the blacks were too soft for my revo running 2 5 cell lipos - i think you likey..

[Finnster]

Hmmm....

So mixed results. I got it my gears and got it finshed, but the ESC is still having trouble. Even w/ 16 cells and 16/51 the top speed was ~25 mph. Very torquey, wheelies easy, but just no speed and a lot of stuttering from a stop.

I ran it for ~5 min, the checked the motor and esc temps. The motor was ~125, but the ESC was 200! Def something not right w. the 9920. Crap.

I was expecting 40 mph+, this is reasonable right? i think I will have to send the Bk off fopr repair or get bite the bullet and get a new ESC, maybe a Q125.

I really only see 3 esc that can handle 16 cells. The Bks, Q125 and the MGM 160. I guess the Q125 is it although I'm a bit annoyed with the heatsink thing.

Thoughts? I had replaced a bad cap on the 9920. Works now, but not perfectly. WTH would cause such high temps? I'm worried perhaps the FETs are messed or something major like that. So smoke or burned components that I can see. BEC jumper is removed BTW.

[Finnster]

" Aoccdring to a rscheearch at Cmabrigde Uinervtisy, it deosn't mttaer in waht oredr the ltteers in a wrod are, the olny iprmoetnt tihng is taht the frist and lsat ltteer be at the rghit pclae. The rset can be a total mses and you can sitll raed it wouthit porbelm.

Thats awesome :):005:

[HotnCold]

:005:

[squeeforever]

I would get the Quark 125 and a pack or two of ram heatsink.

[Finnster]

Originally Posted by HotnCold

:005:

Heheh, I'll have to remember that when I get worried about my crappy typing. Popele wlil be albe to fgirure it out aynway.

Has anyone radared or GPS'd a BL revo? What kind of speeds are acheivble with "normal" setups (ie 14-18 cells)? I always assumed 40 mph as the Novak does mid 30's, and these sensorless are be quite a bit more powerful. Hmm Right now the titans woud give a strong run to the 9920/8xl which just isn't right.

The Q125 sounds good, just not the $280. :007: I was hoping to be able to run until the CC MMMaxx comes out and compare, tho this may be forever and a day.

[BrianG]

25mph can't be right. I don't know if I ever hit 40mph with my 8XL, but it was very fast and my truck was heavy and I was only using 14 cells.

That 9920 might be bad as you pointed out. If you were running on fewer FETs due to some being burnt out, that could cause the heat and reduced performance. Too bad you didn't know anyone that lived near you who would let you try another ESC.

Are your batteries up to the task? That 8XL can pull some current. If they can't supply the current required, the truck will be slower and also cause the ESC to heat up. When I first put my V1 Revo together, I used less-than-high quality cells (just to try it out) and there was definitely a performance difference when switching to GP cells.

[coolhandcountry]

Did you wire the batteries in series or parrellal?
I looked at pic but no esc.