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Is too rich bad?

Old 11-07-2005, 05:57 AM
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HerrSavage
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Default Is too rich bad?

Hi, I got a Savage 25 about a month ago and had a guy from an RC race center break it in and tune it for me. So far so good basically - I haven't even touched the needles yet. Alltogether I've been through about 2.5 to 3 liters of 20% Tornado fuel. It starts up well, runs well, doesn't stall, and seems pretty damn fast to me. However, a couple of weeks ago I managed to shred my first spur gear - I think by trying to power out of some thick grass up a steep hill. The teeth were simply half gone. Then I had a RC mechanic guy install a new one - which I mangled the next day out. It ran VERY well for about three tanks and lots of smallish to medium jumps, and then at the end of the last tank the engine started screaming wildly, so I shut it off. The next day a friend of mine and I replaced it(this time with a 52), and noticed that the old one was like totally melted onto the silver ring thing. Had to hack it off with a knife in order to reuse it(I'm talking about the silver ring thing that goes between the transmission and the spur gear.)

Anyway, with the new 52 tooth installed, I went out drving last weekend and was expecting wheelies more or less at will.. Maybe I'm just wrong in expecting that. It did definitely accelarate better, but towards the end of the tank it started sounding weird - a little dry and screamy or so.. So, is it:

1.) just normal that it sounds that way at the end of the tank?

2.) Or is it possible that the needles - I'm thinking in particular of the low speed - are too rich? I notice on videos I see on the internet that the tune of a lot of motors is a lot cleaner and more even - like kind of buzzy. Mine sounds kind of haggard and jagged at low speed - but it runs well, accelerates about as well as you can expect but without wheelies(well, a couple on grass now and then), and basically behaves fine - no problems starting, no stalls, plenty of power.

So anyway, maybe this is all nothing - I'm at work with an hour to kill before I start. Maybe this all means I should just start fiddling with the needles myself - I know I need to eventually, but if it's running fine now...

But the basic question is, is too rich bad for the motor, and why? On the DVD it says it isn't...... But I read somewhere that if the temperature is too low that that's not good.....

ALSO, what does colder weather mean - richen it up or, I'm guessing, lean it out a bit?....

BTW, I've got a 3-speed on the way, but don't know if I want to install it just yet - maybe wait for next spring to go with a motor upgrade....
Old 11-07-2005, 06:51 AM
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RCDadChicago
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Default RE: Is too rich bad?

Savages are notorious for having a half (or lower) tank leaning problem so what your experiencing is pretty normal.
Old 11-07-2005, 08:59 AM
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Default RE: Is too rich bad?

You need to make tuning adjustments just about every time out! I make 1-2 adjustments per tank of fuel! A long thin flathead screwdriver is always needed.
Old 11-07-2005, 09:33 AM
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HerrSavage
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Default RE: Is too rich bad?

Well I started out a month ago as a total beginner. I've now gotten to the point where I can change a spur gear.. Yes I have the flat-head, but so far I've only used it in conjunction with a rag to clean the motor before putting in the after-run oil. A friend of mine who constantly fiddles with his carb seems to constantly have problems. Mine's been running great and I haven't even touched the needles..

Now I know I'll have to eventually - my post is in a twisted kind of way a question as to whether now is that time. I think it is..

But still, I mean it idles fine, it doesn't overheat(at least according to the spit test, and feeling), and the performance is pretty damn good. I'm just a bit concerned about how it sounds at the moment - running too rich makes it sound kind of ragged, I guess?.. Basically, I touch it after running and if it doesn't burn extremely I assume it's OK. I've got a Venom temp/fail-safe on the way..

Gotta get back to work..
Old 11-07-2005, 11:25 AM
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Default RE: Is too rich bad?

You may want to check your clutch. It's probably glazed a bit, causing more slippage and higher temps. You can scuff the shoes and inside of the clutch bell up with some fine sandpaper to get it to grip better.
Old 11-07-2005, 10:13 PM
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Default RE: Is too rich bad?

I would recommend buying a temp guage just to see where you are at. Tune the HSN so you are consistantly running about 270 degrees F when you are at or slightly below a half tank. Only make 1/8th turn adjustments at a time with a good WOT pass in between each adjustment. Once you get the HSN set start with the LSN. What I did was this: I did a take off and went about 100 ft and brought it back to me. Then I adjusted it 1/8 of a turn, and did another pass. For me it felt better after I adjusted it the 1/8th turn so I did another 1/8 turn in the same direction to see if it got even better yet. I did this til I felt I was loosing power and went back 1/8th of a turn.

If after your first adjustment it didnt get better make a 1/4 adjust ment in the opposite direction and see if it got any better. If it did then make another adjustment in that same direction til you start loosing power then back it off 1/8th of a turn.

It is kind of hard to explain this in writing but I hope it helps. Also, about the clutch shoes. If they are original they have probably worn a lot and like mentioned above should be scuffed up or swapped out for some different ones. The burnt out spur gears is more than likely caused by excess heat from the clutch slipping or something.

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