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High RPM's

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NJRC

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I keep getting high RPM's in second gear when hitting WOT.
I have only been adjusting the HSN little at a time and that only seems to set when it kicks into second and also loses power when setting a bit rich. Right now my LSN is pretty much flush out and HSN is a bit past 4 out but not more than 5.
Is this a LSN or HSN issue that it hits high RPM's in second or is it a gear issue?
Should I be adjusting the trans at all through the adjusting holes on the side of the trans?
BTY....I am running stock .25 with stock gears other than a 48 - 16 spur/cb combo RRP steel swap. I have even tried a 15 and 18 clutch bell and still hits high RPM's so I doubt it's the spur/cb set up.

Thanks
RJ
 
What do you mean by hitting high RPM's? Do you mean that when it shifts into second the RPM's jump up? Because that would mean your gearing is off, but you said your running stock tranny gears, which would mean its something else. I hope I'm not confusing you, I almost confusing myself...
 
what I meant by hitting high RPM's in second......I kinda meant that when it shifts into second, the engine seems to just whine with loss of power. I would imagine that with all that power whining, the truck would go faster but it doesn't seem to move faster. It just whines out.
Hmmm?....does that make sense?
 
Sounds like slippage to me. Maybe the engine clutch, slipper clutch, or transmission clutch. The first thing I would do is check the slipper clutch.
 
If it only does it when you give it full throttle then that means your slipper is loose make sure to check that. but if it happens all the time either your slipper is very lose of your clutch on the flywheel is worn. What I think is happening is when the tranny begins to shift the engine gets to build up power and then the tranny engages throwing all that power on the slipper clutch. Its either that or your clutch on your flywheel is worn, but first check the clutch that is supposed to slip, the slipper clutch, and if that is loose thighten the nut that hits the spring, the only nut near the area.
 
It sounds like these guys have you down the right track. Just remember, when you have a higher horse power engine, there's more strain on the clutch's (slipper or clutchbell) when in second gear. You now have the power to deal with a higher gear, but you need to adjust your clutch's to compensate for it. Instead of the truck picking up speed, your clutch is just spinning wich appears to give you less power and sounds like high RPM's. Both are true, but only because the power isn't making it to the wheels.

I really noticed this with my 21 maxx. The clutch in the clutchbell just couldn't handle much more than 1.6hp comfortably. It would really wind out in RPM's when shifting, but the truck wouldn't speed up. If I backed off the throttle and let the truck catch up with the engine, it would really fly, but my shoes would be toast in a short while.

Now I have a savage with a 3-shoe... I don't have slippage anymore!
 
i know this thread is old but this is exactly what I've been looking for. i think. i think my engine is doing the same thing that NJRCs engine was doing or i dont think its shifting at all. if its not shifting at all, then i would have to change the shifting points right? so where would i do that on my savage? one more question, where is the slipper clutch? i think from what I've been hearing is that mine is loose. how would i go on tightening it?thanks
savager
 
Major props on doing a search first thanks man!


Anyways The slipper clutch is like a brake pad, it is attached to the spur gear (big gear coming out of the transmission). On the end of the spur gears shaft you will find a nut, and then a spring, then your spur/slipper setup. Tighten this nut so it puts more tension on the spring. This should make the slipping stop.

The slipper is meant to protect your truck from tranny damage. Say your in the air, and wheels are going 25mph. When you hit the ground, the tranny is still moving but the tires are stopped suddenly, that breaks axles diffs tranny gears, and sometimes a con rod in the engine. This doesn't happen because the slipper/spur gear setup on the savage.

If you tighten this spring and the slipping doesn't stop, you most likely need a new set of clutch shoes, or to sand the ones you have.
. Those clutch shoes are held inside the small metal gear attached to the engine. Both are cheap or free fixes.

Ask around to find th e proper turns/ tiension on the slipper. If you tighten the slipper too much, the wear and tear will eventually wear parts out in the drivetrain.

Hope it helps.. props again for searching.. you can also search for how to adjust the savage slipper.. i'm sure it's somewhere in the masses of old posts.
 
Another cause could be your shift point. If it shifts to 2nd very quickly, the clutch will slip more before it fully engages. That causes it to heat up and start slipping even more. If you adjust your shift point to shift at a higher speed, it will engage quicker, and also get you into a better power curve.
 
thanks for the help. I'm not looking at my savage righ tnow so its easier to ask here. would i have to take out my engine to tighten it? if i dont then i would go do it now but if i do then ill wait till tomorrow. thanks
savager

also where on the savage do i change the shifting point? is it like the little rubber thing that has kinda two holes on the side?
savager
 
On the spur gear, tighten the center nut against the spring till it's snug. Then back it off 1/2 turn. Let us know how much tightening it took to get it snug, and that would eliminate one possibility.
Nothing has to be taken off the car.
Do you have the manual for it? I'm not sure if you have a sealed or exposed trans.
If it's in a case, then yes, it's a rubber cap that opens. If it's anything like a Tmaxx, there are two Allen grub screws in there, and the one straight down the center you do not touch, but rotate the trans to the one that's slightly off center.
Think of it as a clock that's at 12 noon. 11 would be earlier than noon, and 1 would be later. So, if you turn it clockwise, or towards 1, it would shift later.
When you run the car, you might need to tweek it a hair one way or the other till you're happy with the shift point.
 
I thought you had a savage Rolex?

It's kind of like the maxx adjustment like you said, there's a plug on the side of the trans, the side the fuel tank is on.

Here's a link to HPI's adjustment of trans and spur page: http://www.hpiracing.com/graphics/instr/savage25/S25_P18.jpg

It should give you what you need to know.
 
No, Olds, I don't have one, but lately I've worked on 2 Savages for guys at the track, so you've probably seen some of the questions I've asked about them in the past. One stock, the other a Truckzilla conversion with the .46.
I'm the "go to" guy for engine problems at the track, and I always send the guys to the owner for trans adjustments other than my own. Otherwise I'd have NO time to run.
Many times I've been there, and spend so much time tweeking the other engines that I don't even get to start mine.
 
I pretty much drive alone, so the only tinkering I'm doing is on my own. Most of the times, I don't fix issues in the field, I bring it home, work on it, then head back out. I guess that's a couple of the benifits of driving alone and only being 10 minutes from your house... but it gets old some days...
 

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