new hpi savage stripping spur gears?? man i need help?

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Ok, i'm listing this as a new problem in hopes that someone can help me solve it, my new savage just got broke in, brakes was to tight, I re-adjusted the brake-throttle servo, found the center fixed the brake problem, thought that was why it stripped the spur, took it outside, was tuning it, it wasn't really coming alive as I leaned it out, I thought this was odd, as most f4.6 's start to stand on one wheel, then all at once it strips a spur again, I have a good friend that used to own a hobby shop that told me that maybe my throttle -brake servo is faulty, I just read that my engine plate, could be cracked, I AM HUMBLY ASKING FOR ANY HELP AS THIS IS ONE TIME I'M JUST NOT SURE WHICH WAY TO TURN. THANKS IN ADVANCE FOR ANY IDEAS p.s. the gear mesh was right I adjusted it myself,
 
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Hi, ok, here is what I found, the stainless steel slipper plate was moving around, it had marks all over it, I think its part number 72130, I replaced it, new spur gear, truck running great now, i'm not sure why or how this thing was slipping, but all is well now.
 
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it has scars on it where it was spinning around in there, I replaced it and the truck is working great now, put the hump pack back in too, I can only guess it must have been off from the factory. in any event I was just tuning on it and its running great now. this was the first time I had trouble out of a new savage, but no harm, its working great now.
 
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one more thing, I break my trucks in idling the first two tanks, well as this truck was idling its first tank of fuel, little black shards of plastic was getting on the polished pipe, and other places, remember its new, but I didn't figure out it was coming from the spur gear until the beginning of the third tank when it stripped. just probably a oversight from the factory, n I never caught it until later, everyone makes mistakes.
 

Jam Racing 1

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Jam Racing 1

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Robinson Racing has some of the TOUGHEST gears in the R/C industry, I am using the 48 hard spur and have a selection of hard bells to experiment with gear ratios..... Currently running the 48/16 on my X with the axial 32 and it has plenty of grunt and top speed....

http://www.robinsonracing.com/catalog/savage21-25.html
you can get the combo or buy them separate, either way it will end the problem of melted and destroyed spurs for good.....
 
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thanks, i'm going to change to steel spur gears, ive been looking at robinson racing products, as for idling the first two tanks, been doing that for years n had very good luck that way, I guess theres always room for improvement. thanks
 

olds97_lss

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thanks, i'm going to change to steel spur gears, ive been looking at robinson racing products, as for idling the first two tanks, been doing that for years n had very good luck that way, I guess theres always room for improvement. thanks
I used to do the same 20 years ago, but not anymore. It doesn't seem to do much other than burn fuel, fill the pipe with oil and take longer. As soon as it runs under it's own power without stalling, I gently drive/accelerate/let off throughout the first n tanks and I lean it a bit each tank. The first 3 tanks, I shut it off at about 1/2 tank and put the piston at bdc until it cools to ambient.

Also, before I start any new engine, I take it apart completely, rinse out the engine/crank case with fuel and wipe the internals the best I can with a paper towel and q-tips to remove any aluminum particles. I put ARO on the bearings, conrod ends, one way bearing and sleeve internal/external surfaces. Then I do the whole sealing with RTV process and let it cure overnight.Then I do the break-in. So for me, idling that first tank is totally useless as I remove all the floating garbage by hand before I ever start it in the first place.
 
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I heard a well known racer once say there was no one way to break in a nitro engine, but with that said I always think there is room for improvement if you know the outcome. so let me put it this way my dad had a saying " Let everyone ride their own horse into the sunset and you do what you know is right". RIP dad! just my opinion!!
 

olds97_lss

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None taken. I'm sure we all do some variation of the same thing. I've just been doing my process for many years/engines and it seems to work well without wasting a lot of extra time or fuel and causing even more aggravation during break-in.
 
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I agree break-in can be a big pain, on a good note the savage seems to be running well except for the brakes grabbing so hard it causes it to flip, I have backed the brake adjustment off, way off, it still wants to nose up and flip, first savage ive had to have brakes like this!!!
 

olds97_lss

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What brakes does it have? Dual metal, dual fiber, single fiber? I preferred the dual pink fiber ones. Plenty of stopping power without being grabby. I hated the dual metal ones, they would get very grabby as the center of the disk would wear and bind on the hex.
 
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its got the dual fiber brakes, I even wondered if I could loosen the screws on the transmission that holds the calipers tight. but that doesn't sound like such a good idea, maybe the darn brakes will wear down and quit grabbing so dang hard, if you can think of a solution, i'd appreciate it.
 

Northernnightmare

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Hi again, I would deff go with the RR hard gears, with the plastic spur your lucky to get 3 runs out of it! 16/48 gearing is for regular tires, 18/46 for light truggy tires, 14/52 is for jumbo tires.

Also on your dual disk setup make sure the rear most disc, is not rubbing on the clutch bell I seen it happen a few times now, to people that run miss matched small size bell and spur together. Also get the ofna servo linkage the stock setup is very honky and can cause brake drag or a run on throttle.

I also run the standared 4 pack AA receiver battery pack, They seen to last way longer than a hump pack to me just one less thing to charge all the time....
 

olds97_lss

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Updating your throttle/brake linkage will help in general as the stock setup sucks with that split servo horn. Has been so long since I had that, I forgot it was normal. lol

I just used cheap traxxas sliders, but your better off using plastic sliders if you can find them. I also used a threaded rod for the throttle so I could put a proper ball end on it to remove the slop of the z-bend on the throttle pivot.
 

olds97_lss

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You need:
2 sliders
4 collars
one spring
one long z-bend, can probably use your current brake wire
one long threaded end
one ball end and ball stud or swivel ball/stand off

This gets you the collars, sliders and spring:
https://www.ebay.com/itm/DYN2568-Dynamite-RC-Pro-Tune-Throttle-Brake-Linkage-Set/401103429623

Ball end I think I used for the throttle wire end pivot:
https://www.ebay.com/itm/Swivel-Ball-Links-2mm-w-Hardware-Du-Bro-RC-Airplane-DUB368/401493390902

I normally just pick up the threaded end rods at my LHS. They are a pain to search for online.
 
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