My savage won't willie!

[obbi13]

Hello Folks,

I had just finish tuning and I'm getting nice acceleration with blue smoke. Now, for some reason when I kick full throttle I can see that all the force/energy is being directed the the front wheels and it won't do any willies. Any suggestion / solution, or perhaps point me in the right direction.

Savage-X 4.6 RTR 9 tanks of fuel so far.

 

[Jeremy]

First tighten your slipper clutch down all the way then back it off 1/4 turn .. if that don't work then you might have worn clutch shoes .. if that don't work gear the truck differently .. if that don't work .. NEW MOTOR !!!

 

[Jon]

the front wheels go faster the the rear?? could be a rear diff problem

 

[obbi13]

the front wheels go faster the the rear?? could be a rear diff problem

that's an observation that I noticed. Yes the front wheels go faster than the rears when I put the savage on a block. Can I have a busted diff when my truck is only a few days new?

 

[AllanQ]

Probably not a diff problem, but check your grub screws from your tranny and diff drive cups. those little screws have a tendancy to work their way loose.

 

[Larsenracing]

Yes, you can have a busted diff. The best thing to do is shim them. There is to much tolerance between the Ring and pinion gear and they tend to strip. Have you heard any cracking or weird sounds when driving it?

Another few things to look for that can be missed or broke is the little hex pin(Grub Screws) that holds the dog bone cups in place or a busted dog bone. If either are missing all power will be directed to the front.

I also tighten my slipper all the way down or very close. Maybe backed off 1/16-1/8 turn.

If the truck is only a few days old and 9 tanks threw it, it will take 3/4 of a gallon before you start to see full power and full RPM's.

 

[BlueGroove]

How much blue smoke is coming out as it still may be too rich? If the gearing is at least stock you should have no problem standing up as stated before the clutch is in what condition or are the clutch springs too stiff? just a few thoughts that may help guide you along.

 

[obbi13]

good suggestions all,

I'll try the easy one first, the slipper clutch, last time I messed with it I back it off 1/2 a turn (too much after reading the posts). Then I will check the grub screws and dogbones. and last the diff.

About the blue smoke, it will smoke all the way until i stop giving it full throttle (hope that's lean enough?). I stopped leaning it because the temp will go beyond 250 in a couple of lapses, like one round trip up and down my street at full throttle and there I have 250 or above. I know I can keep leaning it more but my worry is the temp.

 

[Mickey]

if you hold the front tires of the ground will the rears try and move the truck? if they don't check for the grub screws on the center rear driveshaft. does the truck make noise with the fronts off the ground (clicking or crunching)? if it does then get into the diff as the ring gear is probably stripped. will require a new gear and some propper shimming as stated in above post to set proper mesh between the ring and the pinion.

if it does try and move the truck with no noises then pull the slipper apart and see if the pad is glazed. i have had slipper pads glaze over and still slip when tightend all the way down . change the pad and lightly scuff the steel plate that the pad rests against and set the slipper nut to spec. hope this helps

 

[Jon]

try lifting the rear of the truck, turn one wheel, listen for noises, if you hear somthing its probally the diff.
the thing with the grub screw is if it did work its way out the rear wouldnt get any power at all, from what your saying its still getting power just not the same.
also when you check the slipper check the pad and make sure its good.

 

[Larsenracing]

Don't focus on temps so closely. Tune purely on how it runs and smoke trail. Some engines will run hotter. My stock F4.1 ran best between 275-300*. She had 8 gallons thru her till I cracked the block landing a huge jump upside down, Oops.

Obviously watch them some you definitely don't want to run a lot above 300* or she'll be cooked. I guess what I'm getting at is don't be afraid to try it a bit hotter. If it starts spitting and sputtering or holding high Rev's back it back down.

Like I said above it will not be fully broken in or reach full RPM until it has roughly 3/4 gallon thru it as well.

 

[obbi13]

AllanQ and Larsenracing, props to both of you. After close inspection I noticed that the grub screw was missing. I replace it and wallahh, I was doing willies like crazy. Now, all 4 wheels turn at the same time!

Oh, and about the temp, I kept on leaning and I got more power. But the problem is that one good squeeze of the throttle and I'm above 300F in no time. I think I will richen it up a bit. At one point I got exited and ended up at 368F.

 

[AllanQ]

Glad to see you got going. Remember you want good smoke coming of the pipe at WOT.

 

[Shaun]

Don't focus on temps so closely. Tune purely on how it runs and smoke trail. Some engines will run hotter. My stock F4.1 ran best between 275-300*. She had 8 gallons thru her till I cracked the block landing a huge jump upside down, Oops.

Obviously watch them some you definitely don't want to run a lot above 300* or she'll be cooked. I guess what I'm getting at is don't be afraid to try it a bit hotter. If it starts spitting and sputtering or holding high Rev's back it back down.

Like I said above it will not be fully broken in or reach full RPM until it has roughly 3/4 gallon thru it as well.

well said larsenracing!! i've read here at the forum someone saying there engines "sweet" spot was at darn near 300* so it goes to show you each one of these nitro engines has its own personality lol