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Centax clutch adjustment or Engine Needing Tuning?

Centax clutch adjustment or Engine Needing Tuning?

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Old 04-22-2004, 08:43 PM
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Red face Centax clutch adjustment or Engine Needing Tuning?

Alright guys, I just built my R40 and was out tuning the Centax clutch. This is my second car that came with a centax.

Anyways, I don't know if it is the clutch slipping or the engine needing tuning. Whenever I full throttle, it sounds like the engine is going to stall. BUT, whenever I SMOOTHLY rev the car up to full throttle, the car is a beast. I don't know if it is bad tuning of engine or bad tuning of clutch. I followed the directions from the manual with the shimming and spring nut in the centax.

Can anyone help? Thanx
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Old 04-22-2004, 09:39 PM
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I also had a hard time trying to tune my brothers Kyosho 3D clutch. I was doing almost the same thing you describe. At full throttle, it would take a second or two for the car to start moving. It seemed like the bottom needle was too rich. We leaned the needles. We did every adjustment to the clutch. Loosened the nut, tightened it. Everything. Then I noticed his fuel line was like twice as long as mine(8" or so). We cut it down as short as possible and it was an INSTANT fix. The bottom end came to life. I don't know if thats your problem but just a suggestion. Hope this helps.
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Old 04-22-2004, 10:31 PM
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Default Centax clutch adjustment or Engine Needing Tuning?

Guys;

Too long of a Fuel/Pressure lines will may times result in poor response of the Engine.

As a general rule, use the shortest (smooth) path for Fuel line as possible. For the pressure line, start with 1 loop and add more if nesscesary to smooth out throttle response.

Start with the kit/factory settings on the clutch, they are usually pretty good starting points.

Get the Engine tuned acceptably, then work on clutch adjustment.

Last edited by popsracer; 04-22-2004 at 10:46 PM.
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Old 04-22-2004, 11:10 PM
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My pressure line isn't really that long at all.
Attached Thumbnails Centax clutch adjustment or Engine Needing Tuning?-picture-344.jpg  
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Old 04-22-2004, 11:13 PM
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what engine are you running
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Old 04-22-2004, 11:28 PM
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JP Modified RS12. Was running perfectly on the NTC3.
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Old 04-22-2004, 11:29 PM
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where did you get a JP modified I been wanting one for a while
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Old 04-22-2004, 11:40 PM
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Default Re: Centax clutch adjustment or Engine Needing Tuning?

Originally posted by DOMOisCOOL
I followed the directions from the manual with the shimming and spring nut in the centax.
Do a pinch test on the fuel line to the carb to see if your low end is rich.

Secondly, take off the 87097 spring that retains the flyweights. That should give you a more responsive clutch.
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Old 04-22-2004, 11:42 PM
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Hmm, are you sure about the spring?

When I pinch the fuel line, it shuts off in less than 2 seconds. Im thinking low end too lean?
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Old 04-22-2004, 11:43 PM
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Originally posted by hudy
where did you get a JP modified I been wanting one for a while
Go to www.nitrohouse.com
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Old 04-22-2004, 11:54 PM
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Originally posted by DOMOisCOOL
Hmm, are you sure about the spring?
Yes, I'm sure !

Originally posted by DOMOisCOOL
When I pinch the fuel line, it shuts off in less than 2 seconds. Im thinking low end too lean?
Taken from http://horizon.hobbyshopnow.com/Prod...4-ART.asp?pg=3

If the low speed needle is set correctly, the engine should increase rpm only slightly and then die.

If the engine increases several hundred rpm before dying, then the low speed needle is too rich and needs to be turned in.

If the rpm doesn't increase at all and the engine simply dies, the low speed needle is set too lean and should be richened or turned out.
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Old 04-22-2004, 11:57 PM
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Thanks "D"

Looks like my Low end is too lean. Ill test it out tomorrow and will let you guys know the result!
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Old 04-24-2004, 10:00 PM
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Originally posted by InitialD
Yes, I'm sure !



Taken from http://horizon.hobbyshopnow.com/Prod...4-ART.asp?pg=3

If the low speed needle is set correctly, the engine should increase rpm only slightly and then die.

If the engine increases several hundred rpm before dying, then the low speed needle is too rich and needs to be turned in.

If the rpm doesn't increase at all and the engine simply dies, the low speed needle is set too lean and should be richened or turned out.

Where should you pinch at? At the carb nipple or closer to the tank. That would mak a big difference I would think?
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Old 04-27-2004, 10:46 PM
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Originally posted by mckrooz
Where should you pinch at? At the carb nipple or closer to the tank. That would mak a big difference I would think?

Same article from http://horizon.hobbyshopnow.com/Pro...84-ART.asp?pg=3

Step 3. With the engine at idle, pinch and hold the fuel line near the carburetor, cutting off the fuel flow and carefully listen to the engine rpm.

Hope this answer your question....
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Old 04-27-2004, 10:55 PM
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I have the same engine Domoiscool. I'm on engine break in.
Mine is needed the low end turned out to lean it out. Man I got about 10 tanks it's screaming at 190. I had to quick it was getting to dark. Going to finish break in Thursday at Delta.
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