Losi 2.0 Conversion - Page 4 - RC-Monster Forums

SpEEdyBL · 02.13.2009, 08:08 PM

Good news for me. I happen to already have the HD diff case intalled my 8ight.

Shark413 · 02.14.2009, 12:36 AM

Big debate on one of the other forums regarding the Losi Smart Diff not locking up enough. Here is what I think:

"Actually for off road you don't want the diff to completely lock. That was the problem with the Torsen diffs and to a lesser degree the Kyosho LCD diff. They locked up too much and adversely impacted the handling (causing inconsistant handling). The beauty of the new generation of diffs (XRAY, Fioroni Traction and the Smart diffs) is that they have a much smoother action and don't completely lock up. Like having 2K and 7K diff fluid and being able to select between the two depending on what you need, very cool. Diffs that lock up are ok for on road and crawling but not so good for off road."

SpEEdyBL · 02.18.2009, 09:14 PM

What did you use to measure the motor temps? I also have a CC 2650 geared 12/46 and 14/46 and i get temps in the 150-160 range on the endbell using the Duratrax infrared temp probe. With the eagle tree temp sensor, the temps are consistantly 30 degrees cooler and this is using thermal paste and tape to cover and attach the sensor to the motor. All runs so far have been done outside on a road.

Shark413 · 02.18.2009, 11:24 PM

Quote:

Originally Posted by SpEEdyBL

What did you use to measure the motor temps? I also have a CC 2650 geared 12/46 and 14/46 and i get temps in the 150-160 range on the endbell using the Duratrax infrared temp probe. With the eagle tree temp sensor, the temps are consistantly 30 degrees cooler and this is using thermal paste and tape to cover and attach the sensor to the motor. All runs so far have been done outside on a road.

I used the Eagle Tree blub sensor taped to the can using silicone thermal tape. I also have a Raytek temp gun I used to spot check the temps. I didn't use the Raytek when I had the 13T pinion on and only have the Eagle Tree data, later I used the Raytek to spot check the motor temps using the other pinions, I don't recall the exact temps, but they were all higher (140-160 range) I assumed this was because of the higher gearing but as you stated it may have been because of the Eagle Tree sensors. Next time I will use the Raytek on all the test runs to verify the temps. When I first got the Eagle Tree I checked the sensor comparing it to what the Raytek was reading and they were both pretty close. So I am not sure it's off by 30 degrees, but we will see.

Shark413 · 02.18.2009, 11:49 PM

Here is the Eagle Tree data from my test last weekend. Losi 2.0 roller, Losi conversion kit, running a MMM 2650kv combo, 45/13T gearing and a Neu 4s 5000mah lipo, Smart Diff (center), ambient temps were in the mids 60's. Track surface moist, high traction.

Temps, taken off the side of the motor can.

Amps, some big spikes (169 amps)

Pack voltage, you can see it really dip down low when the throttle was punched.

SpEEdyBL · 02.20.2009, 08:13 PM

Thanks for the data.

02.20.2009, 09:10 PM

Hey Shark (or anyone) do you know what parts come with the Losi Conversion kit? I was going to get one for the 2.0 but now I'm thinking I'll use Mike's mount but I'd like the battery tray and radio box and the other goodies which come with the kit. Is there a list of part numbers somewhere? Any help would be appreciated.

Thanks,

02.20.2009, 09:29 PM

Ah, the power of Google:

http://www.horizonhobby.com/ProdInfo...TEexplode2.pdf

gixxer · 10:29 PM

a little off topic but dave you plan on racing it at pinshop this year or wolcott? a few of us plan on doing 8th scale this year and I figure I will get back into it. plan on running the hyper 9 if its out early enough or if I have to I will go with the losi. that smartdiff already has my attention.

I still have never been to pinshop because I have been doing 10th scale at rchr for the last year but come summer time I think I will be ready to go outdoors again.

02.20.2009, 10:29 PM

Pin Shop is my "home" track. I will be there as often as I can but I do plan to hit the Barn and Wolcott every now and again, especially if the 1/8th Electric takes off at those tracks. We run 10 min mains at Pin Shop now so it's a very Electric friendly place even though it's mixed. I'll be running buggy for the first time this year.

gixxer · 02.20.2009, 10:38 PM

cool. I thought pinshop was only doing 5 or 6 minutes last year. anyways since I stopped going to extreme (like 5 yrs ago when u and the gentry's were always there) I have been racing at wolcott and for the last year rchr.

I will still do rchr because they do wednesday night racing and that works well for my schedule but on the weekends I have off I am going to try to make it to pinshop. Dan raced there a few times last year with his hyper 8 and liked it.

What time do they start at anyways? do they have any battery limits?

also wolcott looks like they will be doing friday nights so if that goes well I will do that. If not sundays are out for me(eliminating wolcott) and pinshop will be my only option for local 8th scale electric since they do saturdays.

02.20.2009, 10:43 PM

5 Mins was so last year. This year it's 10...

Not sure on the time, we kept adjusting last year to get the day in before it got dark so I honestly don't remember the way it was during the summer when daylight wasn't a factor.

You (and anyone else in the CT area) should come by! We should have LOTS of electric conversions and it gives you a chance to race against the East Coast editors of RC Car Action Magazine!

gixxer · 02.20.2009, 10:50 PM

sounds good and I have already met them when they have been at wolcott. actually know most of the rcdriver writers too.

I know 3-4 of us from rchr are doing 8th scale this year. 2 already have the cars. I am definitely converting another this year too but will wait till last minute because i want the tekin stuff and hoping to be able to hold out for the hyper 9 too.

see you at the pinshop then. also looking at your videos it looks like you have gotten a lot better since the days I use to race with you at xtreme.

Shark413 · 02.25.2009, 06:56 PM

Some testing data I logged last week. I was trying different pinions and I noted the temps of the motor with each pinion. The first was with a 13T and max temps were 120 degrees, the graph shows the temps with a 15T pinion (138) a little higher, but this made sense since it was higher gearing. Then the last graph shows the temps (176) with a 14T which surprised me because this was lower gearing (than the 15T) yet the temps were higher. I ran the test twice with similar results. 45T spur and Neu 4s 5000mah lipo used for all testing. Ambient air temps were mid 60's.

First run 13T, 120 degrees max after 10 mins.

second run with 15T, motor seems to reach operating temp (136 degrees) then levels off and holds steady.

Last run 14T temps start going up and keep going. I didn't let the motor cool as much as I did for the first two test but 176 degrees still sounded really high.

SpEEdyBL · 02.25.2009, 10:18 PM

That is certainly odd. I had lower temps going from a 12 tooth to a 14 tooth, and also from 12 to an 11 tooth. It's hard to do different runs without changing variables (5s vs. 4s, running area), but this seemed to be the trend.

Did you go back to using a 13 or 15 tooth after using the 14 tooth? One loose connection from the motor to the esc can increase motor temps A LOT. So can bad gear mesh.