SpEEdyBL, I have run the Kyosho Plastic spurs on my first conversions so I can compare how they wear compared to the Losi spur. It's rained the last several weekend so I have not been able to get out to the track. Just running it up and down the street for now. I will let you know how it holds up. The two piece design is kind of cool, will save you a little time and less mess when swaping spurs.

himalaya, because they had to swap the diff around on the chassis and there is no cutout on the chassis in the new position the largest spur you can run with the Losi conversion is 45T. Losi currently makes three plastic spurs 45, 44 and 43 teeth. You can use thicker spacers to raise the diff for more clearence or you can cut a hole in the chassis, but that has it's own problems, higher CG, more angle on the driveshafts, weaker chassis (with another cutout), etc. I am running the 45T spur and a 13T pinion it is very fast, has good acceleration, and is running cool so far (a few street runs only).

One thing to keep in mind for those thinking about the Losi Smart Diff, I am running it in the center but I ordered a front diff. The reason is if you order a center Smart diff you get a 48T sput that can't be used in the 8ight-E. With the Losi Smart front diff I removed the ring gear (which can be used in the front as a spare) and replaced it with the Losi plastic 45T spur. The only difference is you won't have the brake flats on the outdrives but I don't care because I am running motor brake.

Great thread, can't wait to hear how it all performs at the track.

One more thing regarding the Smart diff, the diff case is different from the standard Losi diff case, so the Smart diff internals won't fit. But the optional Losi HD diff case looks like a match. I ordered a HD diff case and should have it soon, I will try and fit the Smart diff internals in the HD case and confirm if it fits or not. If so you can save about half on the smart diff by just ordering the internal Smart diff parts and the HD diff case.

Confirmed, the Losi Smart diff internals fit in the HD diff case. Also I checked the Smart Diff parts list and the part numbers are the same (Smart diff case and HD diff case). But it really doesn't save you any money unless you reuse your ring or spur gear. Because the individual parts just about equal the cost of a compete Smart diff.

http://i142.photobucket.com/albums/r...3/DSC05458.jpg
Here are the part #'s for the individual internal parts, and you will also need the internal springs as well. The one that is covered is part #3604.

http://i142.photobucket.com/albums/r...3/DSC05457.jpg
Everything fits (Smart diff internal parts into the HD diff case).

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

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."

Rains finally let up and I got my Losi 8ight-E out on the track for the first time last weekend. Running a Smart diff in the center and a MMM 2650kv motor. Ran three packs to get things broken in, then three more to see what it could do. This thing is amazing, the handling is much better than my previous buggies and really suits my driving style. The Smart diff seems to be doing the job (definitely more on power traction), but I never ran the standard Losi diff, so I can't do a direct comparison. But compared to my brushless SH Z-Car and Kyosho buggy it does seem to accellerate under power better. I just hope the Smart diff spider gears hold up, they are pretty small and the motor has a lot of torque. I tried several different pinions with an Eagle Tree data logger hooked up to check Amps, Watts, temps, etc. With a 13T pinion and 45T sput, the motor temps were 128 degrees (max) and battery about 105 degrees (ambient temps were mid 60's) after 12 mins of driving at race speeds. I also tried a 12T, 14T and 15T pinion, but unfortunetly my Eagle tree didin't record the data (user error). So I will need to retest. I was using a Zippy, Losi and Neu 4s 5000mah batteries.

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.

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.

http://i142.photobucket.com/albums/r...i001021509.jpg
Temps, taken off the side of the motor can.

http://i142.photobucket.com/albums/r...rk413/amps.jpg
Amps, some big spikes (169 amps)


http://i142.photobucket.com/albums/r...olts021509.jpg
Pack voltage, you can see it really dip down low when the throttle was punched.

Thanks for the data.

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,

Ah, the power of Google:

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

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.

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.

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.

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!

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.

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.

http://i142.photobucket.com/albums/r...k413/losi1.jpg
First run 13T, 120 degrees max after 10 mins.

http://i142.photobucket.com/albums/r...k413/losi2.jpg
second run with 15T, motor seems to reach operating temp (136 degrees) then levels off and holds steady.

http://i142.photobucket.com/albums/r...k413/losi3.jpg
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.

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.

Yeah I agree if 13T runs cool and 15T is ok, why would 14T cause temps to go high. I am thinking your on the right track on the gear mesh. The only thing that was different was the pinion and gear mesh. The buggy, spur and batteries were the same. What has me stumped is I tried the test two different times and had similar results (14T caused higher temps), I find it hard to believe I messed up the gear mesh twice and only when I tried the 14T pinion. Well, I plan on running the test a few more times.

13/45T - motor=128 degrees, battery=88 degrees
15/45T - motor=142 degrees, battery=98 degrees
14/45T - motor=176 degrees, battery=103 degrees

Or you can just say "screw it" and run the 15t :lol:

You know that's what I was thinking. The 15T feels pretty good, faster than the 13 or 14T setup. I am just concerned that the temps (142) well pretty good, would be too high when summer gets here. I like the temps the 13T pinion was giving me but I like the speed the 15T was giving me. I figured 14T would be in the middle and be perfect, but for some reason I am seeing the highest temps with a 14T setup.

What was the kv of the motor in question here?

Dave, it is the MMM 2650kv motor.

I am a little worried because the Losi support site recommends a 13 or 14T pinion with a 45T spur on 4s and that is with there Xcelorin 2400kv motor, and I am using a MMM 2650kv motor which is even hotter.

Losi is not helping much either, in the Excelorin combo manual they say you should use a 14t Pinion with a 45T spur on 4s in a buggy using the 2400kv motor. In the 8ight-E manual they say you should use a 13T and finally the conversion kit comes with a 15 and 16T pinion (but with no recommendations on what to use). Kind of confusing. I think I will go back to the 13T just to be on the safe side.

Well I got the buggy out a few times to the track and I have been very pleased with the quality/durabilty of the Losi conversion. One thing that I am still having trouble with is motor temps, I again tried several pinions with my Eagle Tree hooked up and the lowest temps I got after 10 mins was 150 degrees which seemed on the warm side. So I decided to use a 47T spur which is closer to the stock buggy gearing (48T), instead of the Losi conversions 45T spur. This should give me a few more gearing options. I bascially had to open the hole in the plastic spacer a little bit and grind off a little area under the spacer (there is already a milled out area under the plastic spacer).

http://i142.photobucket.com/albums/r...3/DSC05546.jpg

http://i142.photobucket.com/albums/r...3/DSC05542.jpg
Using a Robinson Racing wide gear which is easier on the pinions because they are slighty wider and have more surface area.

http://i142.photobucket.com/albums/r...3/DSC05547.jpg
Hard to see, but I opened up the hole in the plastic spacer and milled out a small area under the spacer.

Going back to a steel spur?

Do you really think 2 teeth will make that big a difference?

Time will tell I suppose.

Dave, it's probably just me but I stripped the Losi plastic spur after about 5 packs. So yeah I think I will be going back to steel, the Losi spur cost as much as a hardened pinion and when using the Robinson wide spur the steel pinions last a long time. Without a slipper the spur takes a beating, both during acceleration, braking and I just had too many failures using the plastic spur which could cause a DNF during a race. Also, the 47T spur will allow me to use slightly bigger pinions which will last longer (more surface area/teeth).

That is unfortunate news. I just got my new 8T 2.0 and converted it ( http://www.rc-monster.com/forum/showthread.php?t=19101 ) with a Losi plastic Spur. I can't stand the sound steel on steel makes and was hoping the Losi would be as durable as my old Kyosho's were on my CRT.

Did you burn up only one? Any chance it was just some bad plastic?

Dave, the gear failure was kind of strange. I ran Kyosho plastic gears in my truggy/buggy and what would happen is I would knock off a few teeth from either landing with the throttle on or heavy braking coming off a big jump (both are mistakes). With the Losi spur it looks like it melted, or at least the plastic softened. I had an issue with my last run of the day (when the spur gave out) where one of my eagle tree sensor wires got caught in the rear drive shaft. This could have caused binding, heated up either the motor/center diff causing the spur to get soft. I didn't temp the motor on the last run because the sensor that got ripped out was the motor temp sensor, and by the time I temp'd it with my handheld Raytek it had been sitting for a while and cooled off. Until I hear more feedback on how the Losi plastic spurs hold up I will stick with my steel spur. I am also going to try a 2200kv motor to see if I can get my temps down to an acceptable range.

It was running cool before, wasn't it? For me I don't see how gearing the 2650 with a pinion larger than a 12 tooth (40 mph) would be suitable for racing, given the fact that most people like to run 2000 kv motors on 4s.

Well, in a few more weeks off-road should begin here in the northeast and I'll be happy to give you feeback on the Losi spurs. I plan to try them in both buggy and truggy and hope for the best.

Dave, yeah let us know how your vehicles perform. As for me I am going to switch to a lower kv motor. The 2650kv just runs too hot for SoCal summers, so I am dropping down to a 2200kv motor which I have used in the past with good results (performance ans temps).

Update:

I have been using my MMM 2650kv motor for the last month or so and just have not been able to get any consistant temps. No matter what gearing I tried the temps seemed higher than they should be. So I decided to change out the motor for a 1515 size. I had a spare TeknoNeu 1515/1.5D, so I decide to install this into my buggy. The TeknoNeu 1.5D I have is a square can, so I had to remove some of the material from the side of the can. I have found that the 1515/1.5 runs cooler and I can use more gearing options because of the added torque. The extra wires are for my Eagle Tree data logger sensors, they are just temporary and will be removed once I get the motor/ESC/Battery temps where I want them. Also I mounted a 40mm fan to the top of the motor to help with the cooling.


http://i142.photobucket.com/albums/r...3/01010098.jpg

http://i142.photobucket.com/albums/r...3/01010102.jpg

http://i142.photobucket.com/albums/r...413/Image5.jpg

Shark, did you re-tap for 4mm? How did that go being unable to take the front part off?

Dave, first I DO NOT RECOMMEND THAT ANYONE RETAPS THEIR MOTORS. The risk to damaging the motor/coils is very high (there is only a few mm of clearence from the endbell to the coils). And that's why I didn't mention in my post. It is much safer to send it to Neu and have them re-tap or exchange for a m4 can. But that being said I just could not sleep seeing that huge motor held on by two tiny m3 screws, I had several motors loosen up (slip) a few times and I think it could be related to the m3 screws that stretch or the small heads dig into the mount causing the looseness. For the m4 screws I used a mill to drill the holes, with the mill you can set it to only travel a specfic amount, so I measured the depth of the holes and ensured I was well short of the coils. You have to take the motor apart so you can clean out the metal chips. I used a special tap (blind hole) that allows you to tap in a very shallow hole, normal taps have a starter point and they need to be feed deeper into the hole, which could hit the coils. When cleaning out the can I was careful not to blow out the bearing grease/oil, nothing kills a bearing faster than lack of lube.