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Old 07-01-2004, 05:32 AM   #391
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Cain, I wouldn't know what the differences are, I got my kit once the issuea had been dealt with by Academy. The UK importer doesn't hold large stock, so he is always getting fresh, just packed kits.
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Old 07-01-2004, 05:46 AM   #392
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No problem. Just trying to get as much info as possible.

Academy should take a look at the material that other manufactures like MIP is using in there axles, I haven't broken any of those in all the crashes I have had. I wonder if you could use MIP CVDs on the vehicle, maybe something to look into.

The motor mount is something that I am also not happy with, I think they really should use the setup that Kose is manufacturing and I think threeEwes you said you had friends of yours in Korea? They may be able to get the mount, I would contact them and see about that.

The only way I keep the mount tight is to take out that spacer and put ALOT of threadlock on the screw. this seems to work, as when running around the track the motor didn't move at all, even when I broke the axle coming off that jump.

Does the hopup mount that academy makes hold better than the stock one? Is it esentially the same other than the metal it is made out of ?

I just thought of something about the binding. Could it be that the way the axle is stepped that one of the steps is pressing against the bearing more than it would be if it wasn't stepped?

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Old 07-01-2004, 06:02 AM   #393
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The machined mount from Academy is a better fit, and a harder material, as it comes from a solid piece of alloy, machined to better tolerances and is a tighter fit on the machined cam.

Another thing to try is using a spring washer under the head of the clamping screw on the motor mounts, rather than using threadlock.

The thing at the moment is that obviosluy Academy have made this kit to a cost, and tried to keep cost down, it the axle has been made from low grade steel, then there are probably stress lines in the grain of the steel, which causes it to shear under certain conditions. If you then ask academy to make it out of a better grade steel, or titanium, material costs go up, and so does the machining time.

The issue in the UK has been dealt with and we have had better quality axles through, in kits, I do believe there are some driveshaft packs containing the old batch of axles, other than that, we don't have any axle breakages here in the UK.
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Old 07-01-2004, 07:00 AM   #394
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Ok. At least it appears that the issue was addressed in the UK and we just need to cycle through the bad parts to get to the good ones. What will suck for us is that we don't know which are the good ones. As long as MRC replaces the bad ones with good ones free of charge, this should be cleared up fast. What will suck for me is I purchased another set since I need it and these may be bad as well from what I can understand. i think I may swap both axle sides with the new ones to see how they both hold up and return the others to get replaced by MRC.

I like that spring idea, I believe its similar to how AE does it with the TC3 mount and I think I have a spare spring lying around I could use, just need a longer screw.
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Old 07-01-2004, 03:54 PM   #395
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I'm sure all the little things about the sport will be resolved. We all just have to work it out. Our input = a better product down the road..

I have to give Tim at MRC major props for helping me with my sport issues. He has been extremely helpful and I couldn't get better customer service anywhere.

Tim, you'll be receiving one of everything we make.

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Old 07-01-2004, 05:17 PM   #396
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I have finished buikding my kit and have notice some under par things about it, first of all is parts fitment, I had to ream all the sus. arms to get them to move freely, next is the dogbones they should have made them a little larger to fit into the outdrives,I solved that problem by ordering a set of universals for the rear,and last is the motor mount I will be ordering the machined one soon. Other than those things you cant beat it for the money and I think it can be a very cometitive car.I see no need right now to replace the stock shocks they seen ok for now.
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Old 07-01-2004, 06:20 PM   #397
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spreck - Glad to see another Academy driver! Where did you order the parts by the way? from your LHS or online somwhere?

I agree on the dogbones, alittle longer would have been better but we are using spacers or the spring that goes for the driveshaft works well.

As for the arms, I had to ream most of my arms that I have had for various kits, AE especially on the TC3 for some reason. Of my arms, I am happy to say only one of the academy's needed it.

The motor mount I agree could be alot better. If they could use the setup like Kose has, it would be ideal as to have the motor fall out you have to rip the threads in the motor itself. If anyone has friends overseas, ask them if they can get Kose parts. Tim at MRC is also checking to see if he can get some of them too.

The kit shocks will do the job, I am just used to AE shocks so I went that route. If you decide you want AE shocks, online I believe kprc sells them for about 32.50 for a FULL SET of B4 shocks with mounting hardware. I got them for 32.50 shipped by bidding on them. If you can wait its 37 shipped.

ThreeEwes: Love to hear you race report on what happened if you get a chance to post it. Also, do you have any contacts overseas that could get us some Kose parts?

Tim is really a great guy, he doesn't get bothered by all my questions I have. I will also post some quotes from him that he posts on the rc10b4 board to help him out as he does other things too.

One of the really cool things is he owns the vehicle as well and is working on using the sedan version too. he is also giving me some parts out of his personal stuff to get me up and going so I can race tommorrow. Great guy all around.

I went ahead and changed my setup again, this time I am using something along the lines of what the BJ4x4 guys were running:

30W all around
#2 piston in the rear
#3 piston up front ( they use 1 in the rear, 2 up front )
Green springs in the rear
Silver springs up front
Front Bottom shock position in the middle
Front Top shock position furthest to the outside
Rear Bottom shock mount position outer hole
Rear Top shock mount position middle hole

I will also be running IFMAR Stud tires all around.

I think that about sums it up.

Will see how it goes tommorrow.
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Old 07-01-2004, 06:22 PM   #398
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Here is a picture of where my axle broke. It snapped at the point of the pin. I wonder since the pins are so meaty, not enough axle left for the stock metal?
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File Type: jpg broken_axle.jpg (22.4 KB, 133 views)
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Old 07-01-2004, 06:45 PM   #399
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the http://www.raceacademy.net/ is back up and IS ALOT BETTER!

I recommend all academy drivers and those interested post there as well.

One of the drivers there has dremeled the chassis to have more rear droop, says it really improved handling. if I can get a pic I may try it.
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Old 07-01-2004, 08:09 PM   #400
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Cain:

I took the car out to the track for some more test runs. I found a setup that I really liked-The suspension was set up stiffer and with the b3 shocks it helped out a lot. The car didn't bottom out as much but now I'll need to go to the 30w all around and try that.
Overall the car ran much better 2nd time out.
The car ran pretty good I thought until I broke that axle shaft.
Right then and there I decided that wouldn't happen again because I'll run those cheap (kit) black 2 piece steel axle dogbones all around. You can move those around front to back and visa versa.
The car seemed to handle the jumps okay. I'm not the best driver but the car has more than enough power for me...I just need to learn how to drive this model .
I have yet to really open it the car up.
A friend at the track I go to bought a sport also. He ran his before I got there
. He told me that he broke the ear off the pot metal motor mount. He mentions that he moved the washer that was between the ear and the main part of the mount. Tightened it down and SNAP!
Next time out I'll be running the 76 / 15. I'll let you know how that comes out.
As for the kose request, I'll have to look into it.
Believe it not for all the little issues this car has ...to me its so much better than having to even think about "another drive shredded" As previously posted if you look at a losi wrong the suspension arms crack.
"I'll take 4 sb sports please!"

P.S. NIce to see another SB owner-I know you wish to use the kits shocks...after you run it You're gonna want to change them!
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Old 07-01-2004, 08:51 PM   #401
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Chris, that really sucked when that axle sheared off... what did you hit? pipe?
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Old 07-01-2004, 10:21 PM   #402
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I didn't hit anything. You know as you drive south ( the lane right in front of the drivers stand) as I approached the old -tabletop (now its a big hump square top) I drove up it and the car stopped right at the east edge of the bump right at the top next to the pvc pipe. I walked over to move the car ...I thought it was stuck ...gave it some throttle and the car did an automatic right angle turn-because left axle shaft broke at the drive pin area.
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Old 07-02-2004, 12:11 AM   #403
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After looking at the pics of the broken axel I think I may know the problem buts its probaly nothing we are going to be able to fix easily, he goes I race a mugen mst-1 also (gas truck)ank the rear axel was snaping in the exact same placethe problem was the tensil strenght of the axel material. hex drives that slide over the pin had to much slop in them but the hex is not going to break nor is the pin due to the length of it so the fix was to buy alum. hexes that had a pinch screw in them to tighten them down onto the axel/pin assy.This translates to the sb exactly as anytime you take a wheel off this buggy the hexes want to fall right off, a clamping hex would not fall right off and also it would make the whole assy. work as one unit instead of three,and provides more girth to the area of the axel in question. I have flirted with the idea of making some of these to see if they would work,but I dont think the hexes have enough depth to them, The idea is to cut a slot about a hacksaw blades width right down the middle of the hex,stopping at the axel hole, then drilling and tapping a hole making it like a clamp. It works like a charm on my mst so it would probably work here also.
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Old 07-02-2004, 01:28 AM   #404
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OK, looking at the axle, it seems that they are forged then machined axles, and a slight amount of crystalisation has formed around the drive pin hole.

A quick fix for those worried about shearing a stub axle, fish out from the kit box, the set of plastic hex drives, this should be a lot kinder to the axle until your importer solves the problem for you.
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Old 07-02-2004, 01:40 AM   #405
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those shiny drive bones (part numbers sb 016) on the end axle shaft where mine broke was made out of pot or cast metal. Yes it broke at the drive pin location. What I noticed right away is the drive pin hole wasn't round like the pin it was oval shaped. Looking at this I saw there wasn't much meat on the axle shaft to made it strong. No amount of hex adapter modifying is going to fix an inferior axle shaft. I can see those continuing to break until someone MIP, academy, whoever makes an all aluminum cvd and axle shaft.
Since I dont see this in the near future I will run the cheap stock black steel 2 piece dogbone and steel axle shaft all around the car. I know i know those wont break like the sb016.
Something else to consider is that if you didn't want to run the academy rims you may be able to pull the hex adapters off and try fitting (I'll try tommorrow) XX4 , proline or asscoiated rims on the sport-All depends on the thickness of the rim and the length of the axle shafts.
removing the hexs might eliminate the problem.
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