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Old 02-10-2007, 02:56 AM   #451
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John, what are your settings for the low and high speed needle at the moment?
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Old 02-12-2007, 09:40 PM   #452
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Quote:
Originally Posted by JOHN TAN
Hi Shocker,

Can u roughly state down how to tune a engine after break in? I have problem to get more power without overheat the hyper 12 engine...at least my cheapo Cen engine is far better than that...the hyper engine roar when I try to move the wheel/car...maybe require higher rpm than cen...but is there any setting or better way or the clutch (saw the manual dist A -dist B = 0.3mm~1.0mm) to make lower rpm to move the car slowly...
John,
I'm assuming you have already broken the engine in after at least 4 tankful's of fuel, right? Make sure your master needle is at 2.5 turns at starting. If engine is idling high, adjust the idle screw to lower the rpm.
Also, are you having problems accelerating your car from idle? Having to rev the engine higher in order to move? If so, it may be possible your centax clutch isn't properly set. As you stated about distance A/ Distance B, the distance should be no less than 0.3 mm, no more than 1 mm, from where it is indicated on the illustration of the centax. when pushing or pulling, you should not exceed those measurements. But likely, your clutch adjustment nut may be too tight, and may need to be loosened. To loosen, without removing the engine or clutch bell, there is a small hole on the clutch bell, behind the large (2nd) pinion gear. Using an allen wrench, small enough to fit in the hole, catch a slot on the clutch adjustment nut, and turn the nut counterclockwise to loosen. Do not loosen too much, about 1/4 turn, then start the car and check how it responds to your acceleration. When idling, make sure the car isn't moving.
I hope one of these suggestions helps. Keep me up to date on your progress. Best of luck!
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Old 02-13-2007, 07:22 AM   #453
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Quote:
Originally Posted by Delta9
John, what are your settings for the low and high speed needle at the moment?
oh i never noticed that just keep tuning till it can run at reasonable speed in the circuit but the low speed screw head is about flush with the needle while the high speed is between 2.5~3 turn lean out...but overall i can't lean it anymore as I almost saw the engine is too hot to be lean further...top speed is very slow maybe like 50km/hr only...
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Old 02-13-2007, 07:35 AM   #454
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Quote:
Originally Posted by shocker360
John,
I'm assuming you have already broken the engine in after at least 4 tankful's of fuel, right? Make sure your master needle is at 2.5 turns at starting. If engine is idling high, adjust the idle screw to lower the rpm.
Also, are you having problems accelerating your car from idle? Having to rev the engine higher in order to move? If so, it may be possible your centax clutch isn't properly set. As you stated about distance A/ Distance B, the distance should be no less than 0.3 mm, no more than 1 mm, from where it is indicated on the illustration of the centax. when pushing or pulling, you should not exceed those measurements. But likely, your clutch adjustment nut may be too tight, and may need to be loosened. To loosen, without removing the engine or clutch bell, there is a small hole on the clutch bell, behind the large (2nd) pinion gear. Using an allen wrench, small enough to fit in the hole, catch a slot on the clutch adjustment nut, and turn the nut counterclockwise to loosen. Do not loosen too much, about 1/4 turn, then start the car and check how it responds to your acceleration. When idling, make sure the car isn't moving.
I hope one of these suggestions helps. Keep me up to date on your progress. Best of luck!
Thanks shocker...u have mentioned something(clutch adjustment screw) i have never noticed it at all...ok i will try it a few day later as now busy preparing for our Chinese New year...will keep u inform...thanks a lot.
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Old 02-13-2007, 09:37 AM   #455
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Quote:
Originally Posted by JOHN TAN
oh i never noticed that just keep tuning till it can run at reasonable speed in the circuit but the low speed screw head is about flush with the needle while the high speed is between 2.5~3 turn lean out...but overall i can't lean it anymore as I almost saw the engine is too hot to be lean further...top speed is very slow maybe like 50km/hr only...
Could be an airleak, i had to replace the orings in my hyper .12 carb the other day, i had the same symptons, overheating loss of power and not very good speed it was also taking a while for the revs to drop after WOT, replaced orings in carb sealed engine with RTV sealant and its good as new (well it is actually also replaced piston / sleeve / rod) but did the carb first to test and it was the cause. hope this helps, Happy new Year
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Old 02-14-2007, 06:07 AM   #456
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Quote:
Originally Posted by Delta9
Could be an airleak, i had to replace the orings in my hyper .12 carb the other day, i had the same symptons, overheating loss of power and not very good speed it was also taking a while for the revs to drop after WOT, replaced orings in carb sealed engine with RTV sealant and its good as new (well it is actually also replaced piston / sleeve / rod) but did the carb first to test and it was the cause. hope this helps, Happy new Year
oh no...i had try Shocker method...it indeed need less rpm to move the wheels ...but I have found another problem...it will automatic change to high rpm-sound high pitch (like went to 2nd speed where I had not try before yet as i have less than 20min of testing...due to turning dark after my work...can't try it near resident area) when it was idle position after less than 5mins engine run...it happened after i had lower the rpm during idling...

then I suspect the airleak and low top speed r due to the initial stage when break-in my engine as i saw smoke coming out from the engine after less than 20 sec when I manage to start the engine the very 1st time...forget to richen it and let it run at lean setting...but most likely I had damage the piston area... if that is the case...do u think it time for me to change to a proper racing engine engine like REX / NOVA / OS engine...?
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Old 02-14-2007, 08:23 AM   #457
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Replace the o-rings and seal up the engine, First dissasemble and see if you did do any damage when you ran it lean, but if was for such a short time as you say there should be no harm done, tear it down and inspect the piston and sleeve. You got nothing to lose. If you need any help just ask. good luck
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Old 02-14-2007, 10:13 AM   #458
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Quote:
Originally Posted by Delta9
Replace the o-rings and seal up the engine, First dissasemble and see if you did do any damage when you ran it lean, but if was for such a short time as you say there should be no harm done, tear it down and inspect the piston and sleeve. You got nothing to lose. If you need any help just ask. good luck
actually disassemble the machine is the most difficult part for me... I will try to sealup and replace o-ring 1st...Thanks a lot...
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Old 02-15-2007, 06:12 PM   #459
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Quote:
Originally Posted by JOHN TAN
actually disassemble the machine is the most difficult part for me... I will try to sealup and replace o-ring 1st...Thanks a lot...
Hey John,
You shouldn't have to worry about adjusting any needles during the first break in. The carb needles are usually preset from the factory for the initial break in. Do check the carb o-ring, make sure the carb isn't loose, check your hoses(fuel & pressure) making sure there not loose or have leaks, Back plate area o-ring or gasket should be air tight, and make sure the copper washer on your glow plug is o.k. It does seem you may have an air leak somewhere. Check those areas mentioned. Don't get too discouraged, these things happen often, and it requires mostly patience and time, than money!
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Old 02-15-2007, 11:09 PM   #460
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Quote:
Originally Posted by shocker360
Hey John,
You shouldn't have to worry about adjusting any needles during the first break in. The carb needles are usually preset from the factory for the initial break in. Do check the carb o-ring, make sure the carb isn't loose, check your hoses(fuel & pressure) making sure there not loose or have leaks, Back plate area o-ring or gasket should be air tight, and make sure the copper washer on your glow plug is o.k. It does seem you may have an air leak somewhere. Check those areas mentioned. Don't get too discouraged, these things happen often, and it requires mostly patience and time, than money!
Regards
Thanks shocker...I will check those area...but I don't notice there is any leakage...my previous rc car do have leakage as I did noticed some area have lot of fuel splashing around...if worst come to worst...should I get OS or Nova or REX engine?
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Old 02-18-2007, 05:30 AM   #461
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John Tan, I had problem with running in my first Hyper 12 pullstart motor and it turned to paperweight very quickly. My first motor was Force 12. With the fuel mixtures adjusted during run in I had it running at 80 degrees C and maintained it with car on blocks at moderate revs. The Hyper 12 was a totally different beast and I tried same with engine temps climbing skyhigh to over 160 degrees C. Definately didn't work and advice was to run up and down on road to break in and tune car on track keeping in mind basic factory settings. With my car I suspect that the fuel tank was one of the problems causing lean out. You also need to keep an eye on the centax clutch setting as these motors don't like being loaded at idle. I would also replace the factory air cleaner to a domed pro type foam one to reduce the induced air resistance into the motor. I drove my GPX4 RTR Hyper 12 after not driving for about 12 months on local track and it ran well. Prior to this I used to flame out with 1/2 tank of fuel prior to changes (and new motor). Good luck!!
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Old 02-18-2007, 05:37 AM   #462
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Quote:
Originally Posted by vc05hdt
John Tan, I had problem with running in my first Hyper 12 pullstart motor and it turned to paperweight very quickly. My first motor was Force 12. With the fuel mixtures adjusted during run in I had it running at 80 degrees C and maintained it with car on blocks at moderate revs. The Hyper 12 was a totally different beast and I tried same with engine temps climbing skyhigh to over 160 degrees C. Definately didn't work and advice was to run up and down on road to break in and tune car on track keeping in mind basic factory settings. With my car I suspect that the fuel tank was one of the problems causing lean out. You also need to keep an eye on the centax clutch setting as these motors don't like being loaded at idle. I would also replace the factory air cleaner to a domed pro type foam one to reduce the induced air resistance into the motor. I drove my GPX4 RTR Hyper 12 after not driving for about 12 months on local track and it ran well. Prior to this I used to flame out with 1/2 tank of fuel prior to changes (and new motor). Good luck!!
Hey Mark, you know the rules have changed this year for sport class. you can run any 12 pullstart 3 port , allowing you to get a novarossi you so much like to get. the hyper 12s are what you pay for, they are chaep and hard to tune. how did you go withyour shocks today. makes big difference hey ?
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Old 02-18-2007, 08:01 AM   #463
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Quote:
Originally Posted by vc05hdt
John Tan, I had problem with running in my first Hyper 12 pullstart motor and it turned to paperweight very quickly. My first motor was Force 12. With the fuel mixtures adjusted during run in I had it running at 80 degrees C and maintained it with car on blocks at moderate revs. The Hyper 12 was a totally different beast and I tried same with engine temps climbing skyhigh to over 160 degrees C. Definately didn't work and advice was to run up and down on road to break in and tune car on track keeping in mind basic factory settings. With my car I suspect that the fuel tank was one of the problems causing lean out. You also need to keep an eye on the centax clutch setting as these motors don't like being loaded at idle. I would also replace the factory air cleaner to a domed pro type foam one to reduce the induced air resistance into the motor. I drove my GPX4 RTR Hyper 12 after not driving for about 12 months on local track and it ran well. Prior to this I used to flame out with 1/2 tank of fuel prior to changes (and new motor). Good luck!!
Thanks...no wonder so different from my previous CEN engine...will check it out soon...so u mean u still using hyper 12 engine? or other engine?
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Old 02-18-2007, 08:03 AM   #464
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Quote:
Originally Posted by Pattojnr
Hey Mark, you know the rules have changed this year for sport class. you can run any 12 pullstart 3 port , allowing you to get a novarossi you so much like to get. the hyper 12s are what you pay for, they are chaep and hard to tune. how did you go withyour shocks today. makes big difference hey ?
Hi Patt,

Is Nova engine a good enough for racing? what about compare to OS engine?
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Old 02-18-2007, 10:44 AM   #465
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Quote:
Originally Posted by JOHN TAN
Hi Patt,

Is Nova engine a good enough for racing? what about compare to OS engine?
Hey John,
I can't speak of the Nova engine, for I never ran one. But those who run them and their track record, they are highly recommended. Because they are high end Italian engines, even the stock one's are going to be expensive. On the other hand, I do own and run the O.S. TZ 3 port(P) engine, and I can speak for these.
I run an EB Modified O.S. .12 TZ 3 port(P) engine, and I highly recommend one. It is user friendly, easy to tune, plenty of power & torque. This engine is tough and bullet proof! In fact, on the dynometer, it's power band is nearly linear to an electric motor! Check R/C Car's website on September 2005 product test article for proof. For the cost of an Italian stock engine, you can purchase an EB Mod, Murnan Mod, Zeppin Mod, or the new O.S. Speed Tuned TZ! Even a stock O.S. TZ can hang with any any high end stock engine! Any choice of the above is fine.
Just my two cents
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