Uumh, no!

It start every other engine the right way.

Alright, I have been hearing this solution / theory a lot know, so I guess it's time to try it out.

Maybe I'll try to change the taper of the low speed needle as well. Somebody told me that they are very blunt and actually act "digital". It's either on or off.

Thanks buddy, keep 'em coming. We'll get the sucker, sooner or later

Stefan.........I probably wouldn't bother with the taper of the needle. Just run it rich on the bottom.........Tight clutch...........and tune the HSN for top end performance. Your lean bogging will go away. I spent a whole afternoon figuring that out. I believe my low speed needle is 8 turns out. I know you will be tempted to lean on the lsn as all engine tuners want to......... but resist the temptation........It will sound fat........and it wil be......but on the track it will be fine. The other big plus..............is when the others are struggling to make mileage............you won't!

Pipe too short

where have you been Ed??

Original Picco 2607 pipe, as recommended by the manufacturer and as run by most people who have this engine.

Hi Edward, long time no speak.

How are you?

Hi Tomy it is very long story and now it is all over-I am back

Hi Stefan.
I am OK, feel different now. I am not working for Axial any more, got another job.

Wow this is huge Edward, no more Axial????

Excellent news!

Hi Edward, you say you feel different now. I hope better?

I didn't even know that you worked full time for Axial. Did you quit your maintenance job that you did before?

I didn't quit mainetnance manager position-last year while I was in Fl on Winternats company went out of business, after I came back I was offered to work for Axial. Now I am no longer work for Axial.

Thanks a lot Alfonso.
How are you been?

I dbout it , sounds like a hydro lock when flooded sending the piton back the opposite way , the only place the pressure can escape is out through the carb..

I could be wrong..

Ok heres another theory , Do you have an MSN on any of these carbs ? if so feel how loose it is .. if its not tight as a squirrels nuts then you will have tune probs. Take out the MSN and cover the end seal with plummers tape, make sure you only cover the very end of the seal, screw this back in and see what happens..

the problem you are encountering in my opinion is tuning the engine from a full tank. If you were to tune the engine from half to 3/4 empty you would have a better average tune. remember the tuning on these things changes as the tank pressure changes. When you are at half tank you have an average pressure. When you tune from a full tank you have plenty of fuel pressure, forcing fuel into the carb, you lean it to suit, but when the pressure drops you have less fuel = lean engine. this can over heat it to the point where the power dropps off out of corners when the lsn is too lean or it wont go hard till you hit half way down the straight, meaning too lean on HSN.. When this is left for too long you will pre maturely wear the piston on the exhaust side and cause blow by .. then all sorts of other problems occour.. and tuning isnt gonna fix it .. When its cold it will seem like its got heaps of pop , but at temp the flat spot on the piston will allow compression to escape and stoppig the pupm effect of the engine. This leans it out even further cos thers no suction to draw the correct amount of fuel on the down stroke ..

So best way to fix this is to tune it right from the start , if once you got the tune right and one day its all out .. dont try to fix it with tuning , look around the engine for a cause or strip down the engine to see why its changed.. Unless you have a crappy carb with loose needles you should only ever have to make very tiny changes to tuning if any .. I tend to get a tune on an engine then leave it .. dont be tempted to lean it off when you start it cos it seems rich... it takes half a tank to get to operating temp..



Hope this helps !

Cheers mM

Hello All,

I have recently posted in the Serpent 720 thread about a similar issue. My motor is beautiful for 2-3minutes then slpowly looses power to the point its like running a blackcan. This happened in both motors I tried(Mention they were both working perfect fro 3weeks then all of a sudden this happened)

I am using the Mega ZX12 Race and Mega MF, both had the same issue after my 3rd qualifier when the issue happened the motor just lost power. I took the motor apart (both) cleaned and everything to inspect but there were no leaks or anything no unusual wear nothing. I then took the tank to a air compressor and blew it into the pressure nipple. turns out almost all of the air was esacping through the cap, I applied a little bit of pressure to the cap, and I mean alittle and voilla it all came out the fuel resevoir.

It may not seem noticable but try it(if you have an air compressor, rember these engines at high RPM are forcing through alot of air. I have read elsewhere people using fuel filters on the pressure line to decrease air pressure and volume going into the tank. I will try this this weekend with a new cap, spring and seal of course. Hopefully this will solve the issue.

Also I have heard wind that using the wrong glow plug will cause this isue, but I dont know about that as I was using a NR 7Cold on a day with medium humidity and about 24-27deg celcius which everyone else was running and both motors experienced the same issue.

It has to be a result of air leakage, anyone else have other thoughts?