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Spur / CB Problems

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F

frensham

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Hi Guys

I bought a 2nd user SAVAGE X 4.6 which came with a 17T clutchbell and a plastic 49T spur gear. It ran for about 15 minutes and then the spur gear stripped. during the run I got it to really open up, do wheelies etc so I know it wasn't a bad buy.
It needed a complete clean down anyway so I completely stripped it, cleaned and made it look brand new but noticed one of the engine brace mounts was cracked in half. It was still absolutely rock solid fitted/screwed in from the bottom and from the TV plate but nevertheless it was in two halfs just where it curves.
I replaced it, and also put in another 49T spur plastic and got it going again.
then 15 mins into the run over some general grassfields the spur stripped again.
So now I am stuck.
I notice the 4.6 engine has a 17T clutch bell. I'm kind of new to this and been reading all the various spur/cb posts but am confused.
I am absolutely my re-fit of the spur/cb was perfect (i did it with the paper trick), the mounts or engine plates have not moved.

So my questions are :
1. Is there such a thing as hardened clutch bell ? and is this why it is eating the plastic spur?
2. If so, how do i know if my clutch bell 17T is hardened or not ? it is metal - thats all I know.
3. If it is hardened, could this be why plastic spurs are being eaten. Am I suppose to use metal spur gears?

Finally, based on the 17T clutch bell being good (which it doesn't look bad), what is peoples recommendations on what spur gear to go for ?
I'm looking for middle of the road type usage (flats/grass/rough).
ps - it has a 3 speed gearbox (if that has anything to do with it).

I know I've got so many questions within questions, but really need a pointer on what to buy ?. I'm over in the UK.

Thanks in advance
David
 
How are the bearings in the clutch bell? If they have any slop or a gritty feel, they must be replaced. After using the paper method, check the mesh, the entire way around the gear. There should be as little play as possible, while still having play. Makes sense, huh?:) But there has to be just the smallest amount of play to let the gears spin freely. Too much or too little, and you'll blow teeth off of the spur. The clutch bell should be fine as long as the truck has never had a metal spur on it. Also, give the inside of the clutch bell a light sanding with fine sand paper. Do the same to the shoes and clean all the dust off of both.
 
Check your engine cross braces too. One screw might have fallen out and now your engine plate is twisting.

Running a hardened cb isn't going chew up n your spur gears. The hardened cb's are vented, the non-hardened are solid in the front by the pinion. I run a steel spur - ehh why not. That being said, I do have perfect control over the trck while it is mid air. You don't want to land on the throttle with a metal spur, even though there is the slipper.
 
Clutch/Spurs

Thank you for posting help.

Ok, sorry in advance for stupid questions back.

first - what do mean gears may be too loose - are you referring to the 3 speed gear box? - if so, when I stripped it down, it was clean, smoothly moving, had a nice movement feel to it.

second - checked the brace bar - still absolutely rock solid.

Ok, My CB doesn't have vented holes. therefore I have to assume it is NOT hardened. Therefore, I am going to re-check everything once more and fit my last and only HPI 49T Spur Gear.

Unless there is anything else, I'll let you know.

Tx in advance.
 
Luck I think but more help please.

Hi guys

I've stuck it in, done everything by the book and your advice. and just gon through one tank in a big car park up and down without any gear problems.
I've even rolled it a good few times.
and it is all ok. No wear at all.

Any comments on whether the problem may occur once I've taken it on some grassland/park type ground where the ground is much more up and down causing the body to flex?

anyway, lets try that tomorrow.
I have however now got two more questions.

1. How can I tell if I have a three speed gear box? I have three holes on the side covered using a rubber bung (if that helps).
I ask cos when I opened up the throttle, it really booted it and you can hear it changing to 2nd and really see the speed, but it just wouldn't go into third. I'm asking only because maybe I've been duped on the purchase.

2. I also noticed (I think) that at some points during my acceleration the engine kind of sounds like it "farts" (sorry for the lingo), kind of gurgling or struggling to get fuel. It is running very rich at the moment, and it does wheelies.

Look forward to hearing from you soon.

D
 
Hey fresham,
You sound like your having a blast!
You should hear the 3 speed shift into 3rd. It will do it farely quick after 2nd if your truck is tuned right. Other than that you will have to tear it down to find out.

Ya they will gurgle a bit if they are lean on the bottom end, try turning your LSN 1/8th of a turn counter clockwise.

I would suggest getting a steel spur especially if your running on grass. I went through 3 plastics before I bought a steel and that was 3 years ago and the steel is still running strong. But if you do go steel spur you HAVE to get a vented/hardened CB or you'll start chewing up CB's just like you were spurs.

Good luck. and good questions.
 
Excellent

Hi

Thanks for the comments on this. As I said in the other post you posted an answer; I'm getting the steel spur but looks like I'll need to get a vented clutchbell.
Mine is currently a 17T metal, so I am assuming from your posts that won't do and I need to get a vented one. If I am goign for a 49T metal spur, for average grass bashing/messing around what bell did you suggest I go for.

Tx.

David
 
No 3 Speed

Ok Guys
Finally found my answer. IT DOES NOT HAVE A 3 SPEED GEAR BOX.

It only has 2.

Cest la vie!.

Therefore, no my question is - "Is it worth having a 3rd high speed gear?"

Thanks for your help.
 
do a bit of a search on here on 3 speeds. I have heard they are great and also heard they are a waste of money and barely make a difference. Everyone's own opinion I guess. Do a search and make your call.
 
The Savage has two different 3-speed arrangements.
The original gave you a lower first gear, but the top end was virtually identical to the 2-speed (no improvement on speed and twice as many shift points to fuss with).

HPI then came up with a high speed 3rd gear to upgrade that.
http://www3.towerhobbies.com/cgi-bin/WTI0095P?FVSEARCH=77065&search=Go
Which means that you also need this:
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXSVW1&P=V
or this
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXKAD7&P=ML

Is it worth it?
I'm trying to figure that out myself... lol
My fav Savage is still equipped with a 2-speed (17/48 CB/spur combo).
I've got another Savage with an upgraded 3-speed in it and I'm at the point of trying to dial in the shift points.
 
I have a problem along the same line.. I just bought a savage x 4.6 right out of the box.. ran through the break in cycle well.. the 5th tank of fuel i was able to be a bit harder on it.. it took off.. wheelies, everything id expect.. and then it just started slipping i had no clue what it could be after inspecting it i found the spur gear stripped.. went to the lhs bought a new one and replaced it.. got a chance to check it out this afternoon and after a few warmup laps i got on it again.. it runs great and then it tore up another spur gear.. what do i need to look at on a brand new truck.. thanks
 
Being a brand new truck the engine mount screws maybe vibrating loose allowing the engine to slip a little bit, it doesn't take much. Did you use blue loctiite on the mounting screws when you installed the new spur gear?
 
Hey, my savage did that once, turned out to be a cracked engine mount, had to look close to find it, replaced the mount, problem was solved. hope this helps. kdogg
 
gear mesh gear mesh gear mesh! even if you are replacing the spur gear with the same tooth gear you always need to check your gear mesh. the gears should go together so that there is a little bit of play in the gears. you must adjust gear mesh by sliding your engine back and forth. the gears should spin freely and while holding the CB or the spur with your finger, you should be able to gently rock the other gear. to tight of mesh and the teeth are forced together, the teeth will begin to wear and soon will be completely useless. to loose of mesh and the teeth will try to skip over each other. you want the teeth to gently slide and flow as a whole, complete unit.
 

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