Can someone pm me pato email, need help tuning cera engine. Thanks in advance

If you are still looking for one, I have a new one left over from my Go inventory.

Really depends on air temp, nitro percentage and application. P3 or p4 is best bet. P6 may be too cool. More for onroad racing with high reving motors.

You only ever want to run P3 or P4. If less than 25C, P3, if more than 25C P4.

Guys, now i neef opinion. Is not carb problem as i swithed to 2 needle carb but problem persist. Change pipe same problem. Is choking up as i apply throttle (more than 15% n above).*Will this happen due to*1. cluch setup*2. Front/rear bearingI had break in 10 engine or more but never experience this problem. Some inspection on the p/s/c all in good condition. Please help. Thanks

Your needle settings on the 3 needle carb sound way out.

The msn is factory set flush with the housing on the carbs and should remain there. If you have screwed it out the bottom end will be super rich (as it moves the fuel delivery tube away from the low speed needle).

Set the msn flush with the housing.
Remove the high speed needle brass tube completely. Now look down in to the carb through the threaded hole. If you rotate the msn slowly you will see two fuel feed holes 180 deg apart.
Set the msn so it is flush with the body and you are looking directly down one of the holes in the fuel tube from through the hole in the high speed housing.
That is the sweet spot.
Refit the high speed needle assembly and don't touch the msn again.

Your high speed needle sounds very lean.

So rich bottom with the msn out of whack, then lean top with high speed screwed in to far.
That's why it's choking up on the bottom end and lean bogging on the top - and probably blowing plugs.

Start tuning with both needles flush - it's safer that way as you will always default to a rich setting.

Also screwing the needles right in and then backing them out is a recipe for chewing the very fine ends of the needles up by jamming them in the jet if you screw it in too far.

Your low speed needle might be close - but you won't know with the msn screwed out like you have it - as the whole fuel tube / low speed needle ball park is moved when you shift the msn in and out.

Hope that helps.

Thanks again shane, u always helpful. Will try tmr. If i change to go 2 needles carb which i'm familiar with but same problem. What would u suggest

I doubt you would be having bearing issues on a brand new motor.
Maybe check the head bolts are tight - they can loosen up during the first 10 tanks or so with the the first heating and cooling of the motor from new.
Same for the carb pinch bolts.
Old fuel ?
Idle gap too wide will give you a rich bottom combined with a lean top as a rule.
Fuel lines ?
Tank lid spring or seal ?
Tank cracked ?

Hard to say. It could just be tuning, or an air leak somewhere making you tune rich to cover for it down low.

I'm not familiar with the Cera, but I can't see it being different to any other GO based motor.

My guess is the lsn is too lean and is restricting it at higher rpm. This is a common problem with all brands with a long lsn. Try richening the lsn and you will have to probably widen the idle gap.

Rex

[QUOTE=grizz1;13440122]Your needle settings on the 3 needle carb sound way out.

The msn is factory set flush with the housing on the carbs and should remain there. If you have screwed it out the bottom end will be super rich (as it moves the fuel delivery tube away from the low speed needle).

Set the msn flush with the housing.
Remove the high speed needle brass tube completely. Now look down in to the carb through the threaded hole. If you rotate the msn slowly you will see two fuel feed holes 180 deg apart.
Set the msn so it is flush with the body and you are looking directly down one of the holes in the fuel tube from through the hole in the high speed housing.
That is the sweet spot.
Refit the high speed needle assembly and don't touch the msn again.

Did what u suggest, will try out tmr, as your suggestion the mid needle is 1.5out from flush. Anyway i got extra fuel tube n tank standby to be replace. i did both needle on flush everytime i messed up.

Additional info for new cera motor i got last week is:
Mid needle flush to body
Hsn 2.5 turn in from flush (i flush it to break in with aluminum foil)
Lsn 2 turn out from flush
Idle gap 1.2mm (roughly)

I did refer to arrow thread for break in with success but once after 8 tanks try out WOT but started choking n onwards it choking when more than 15% throttle. Initial felt is this motor is strong but just cant get it run on full potential. I will give more detail if needed for help purpose. Thanks again

Will try that as well. Just replaced to original cera carb n try again. All inputs is golden n appreciated. Thank you very much

Yes I am. If you want to pm me a price and your paypal address, hopefully we can work something out. My zip code is 25414.
Thanks, Mike

After reading the last few posts I have some questions.

1. Is a 3-needle carb inherently harder to tune than a 2-needle carb?

2. What is a good setting for the idle gap when you are breaking in an engine? Do you ever change it after you get through the break in period?

3. Do you take a different approach to tuning when the LSN is long instead of short?

Hi Rich,

No, with the GO "3 needle" it's really no different.
The 3rd "needle" is not a needle as such, just a moveable fuel delivery tube.
It's factory set, and really there is no need to touch it - so in effect your tuning a standard 2 needle carb with a long lsn.
If the mid range fuel tube adjustment is set at flush with case (fuel delivery hole directly below the HSN inlet as described) - factory setting, it should be a breeze.

On the long needle lsn carbs, the high speed needle doesn't really come into play as much as a short needle carb. It's basically just a fuel tap.
You need to ensure the high speed is set rich enough to allow fuel past the thicker long lsn right through the rev range.

A common mistake on long lsn carbs is to have the top end too lean (it only has to be by an hour or two).

There are several very in depth posts on here in the old GO threads about the tuning differences.

Because the GO engines are so tight when new, it's often necessary to run a high idle to keep them going during the early tanks.
Once run-in you can set the idle gap and tune for racing.
Just set the idle to a point where you can run the motor around without it stalling.
You want to be on the rich side (not super rich) for run-in anyway, so the wide idle gap will help with this.

Guys, i changed to other engine with same chasis n same problem then I'm sure is the tank. So will try to tune cera this weekend so i'll share some trobleshoot:
1. Ensure needle setting corect (carb)
2. Plug/igniter in excellent condition
3. Good fuel

If all above good then sure something wrong with chasis:
1. Exhaust
2. Fuel hose/filter
3. TANK x0x0

Thank you everyone with so much help n information provided... This is nitro, when u suffer, you become greater...