@chris,

We run the F11 today but a lot off flameouts, please let me know what fuel i must use.

gr Michel

Hi.

I was a mechanic for a F11 engine in November - RB 25% fuel and RB plug. Before the race it had only been running at idle speed in a bench for 30-40 minutes.
During practice and race we tuned it a little rich (slow 2 stroke). It ran ok under the practise. An ok performace are not enough for us even during break-in , so we changed the plug to a Novarossi C6TGC. Now the engine ran so much smoother even in the cold surroundings (5 -10º Celsius). Still rich HSN.
I don't know if the original plug just went bad after the bench break-in, but for now on he will stick to Novarossi plugs.

RMV Germany, the distributors for RB here, recommend that if you run Tornado fuel(as I do), then you should use OS plugs. I posted the link here somewhere - maybe in the F11-specific thread..

The power of a Cross10 or 11 is very smooth but still has good power for a buggy. I ran one quite a bit in my buggy, I feel it would not have enough grunt to get a truggy around the track very well so to me it's a buggy only engine. The top end on it is also good, just make sure you take your time breaking it in before maxing it out on the top end.

There could be a ton of reasons for flameouts. Like others posted you should first look for a hotter plug, the RB#5 or the C5TGC Nova plug. The F11 makes a lot of power so even tho it feels fast it is probably still rich and the #6 plug that the engine comes with does not burn hot enough to keep an engine running at a rich setting. If the OS plug is all you can get they will work but try to always use the OS once you make that switch. I would try the Nova C5TGC first honestly.

How much fuel have you ran thru the engine? When does it flame out? After idling for x amount of time? Only when you pull full throttle? After pit stops?

Chris,

Flameouts during the whole tank off fuel, not only after a tankstop. We have + 1ltr on the engine now.

A teamdriver here in Holland says to use the OSp3 and an extra head shimm 0.2mm. We use Tornado offroad comp fuel 25%.

gr Michel

The extra headshim is probably a good idea if you are running at sea level where you are with a P3 plug. Those plugs are very hot and have a thin wire so the extra shim should help not breaking the P3.

The Nova C5TGC plug is a hot body plug and the hole for the plug coil is bigger like the OS P3 plug is. If you don't have extra head shims and you have access to the C5TGC plug you can try that first but you want to make sure it's the TGC hot body plug.

Ok thanks

How important is the head-shim? I run Tornado (%25 "Ready 2 Race")fuel, so I guess when I get around to breaking my F11 in I'm going to use an OS P3..

I'm about 100m above sea level btw.. I normally never mess with head shims..

Quick search on German ebay for the hot Nova plug you mentioned..., nothing... Could probably find it in a shop somewhere, but I've been looking at ordering a 3-pack of Bullit plugs for the RB and my Argus and Go engines..

IMO, using an O.S. glowplug in any Novarossi based engine is
a big mistake. The O.S. glowplugs will deform the sealing
area of the head button, then you will encounter sealing
problems if you decide to switch to another brand of glowplug.
The O.S. P3 glowplug is way too hot and very fragile to be
running in these engines. The only reason for running a plug
that hot is that it will make an out of tune engine seem like
it's dialed in. The RB and Novarossi glowplugs will outlast
any O.S. or O'donnell glow plugs made and they don't cost that
much more.
Why go the cheap route and take the chance of ruining
a piston and sleeve by dropping a glowplug coil into the
cylinder ?
Buy a quality glowplug of the proper heat range
and you'll get many gallons of trouble free performance
out of that fine engine.

+100!!!

And please check the thread in the head and the plug after putting an OS plug in a Novarossi based engine: "Nice" metal pieces all over... Oh... any of those parts went into the engine?

The head shim is mainly to play it safe because the OS P3 plug is a lot hotter than the RB #6 plug. I know of people at sea level that run 30% with #5 plugs thru the RB's and they don't have any problems. The OS plug is probably a little hotter than the #5 plug and is probably why people add the shim.

I also agree that running the OS plugs is not a good idea even tho many people do it. The taper angle at the bottom of the OS plugs is a little different than RB and Nova plugs. Will it work? Yes? Will it mess up your head button? Maybe maybe not but like rage said the RB and Nova plugs last way longer!!! You should be able to leave the headshims the same and just get the C5TGC plug and be just fine. I have always felt the RB 6 plug was too cold but I run at 6,000 feet elevation so what is too cold for me can be perfect at sea level. I normally run #5 plugs and pull a thin shim with 30% nitro because of the elevation. I have also ran stock shims with 50% and had no issues but this is because of my elevation.

NVRC5TGC is the part number for that Nova plug I was talking about.

http://www.amainhobbies.com/product_...-Glow-Plug-Hot

It's not a question of cost - if anything the RB and Nova plugs cost a few cents less over here(assuming I can find these hot ones you're mentioned..)

What makes me seriously consider it is RMV Deutschland recommending it for people who run Tornado fuel.. Tim Reckward would know what he's talking about I think. Also, if I do start off with OS, I know to stay with OS..

http://www.rmv-lounge.de/2011/02/21/...inem-rb-motor/

It's in German, but it basically says the oil in Tornado is different or something, so the idle can get critical, or have other flame-out or tuning issues. And that they have found that with Tornado OS/Ninja P3's and P4's work pefectly..

I've got a couple months til the weather changes, so I'll look for a Nova plug first I guess..

ps I'm not necessarily a fan of OS plugs either. Couple years ago I bought a new Orion .24 new and unused from a guy in a forum who had put a P3 in it.. Broke it in with the P3 and then had huge issues, changed to Orion plugs(I know I know, AFTER OS...), and the whole experience was a PIA.. Everybody here in Germany though seems to swear by OS plugs.. I've also got a used REX/NR that came with a P3, raced it in my last buggy race, and it runs fine.. So I don't know. There seems to be some skepticism here in Germany about the whole OS plug not working in NR and other engines thing.. And as I recall btw, the old chart showed NR and OS plugs having the same taper, whereas Sirio, Picco and some others were the ones with different tapers..

I am sure the OS plugs work great for many people as it's an ultra hot plug that will essentially force the engine to stay runing even when your tuned on the rich side. All I am saying is I run at a MUCH higher altitude than most and if you know how this effects an engine you know that I have to run very hot plugs and/or pull out headshims. If I can get the engines running on HOT nova and RB plugs there should be no problem with making it run great at sea level with a hot plug and stock shimming. Adding a shim is much like running a colder plug. So going up a headshim and hotter in plug is basically countering or compensating for the other change. If your engine is over shimmed you have to run a hotter plug to keep it running. If your shimmed low for max power you will need to run a colder plug to avoid detonation.

Below is an RB plug on the left and an OS on the right. I know personally I will run what is made for the engine. I have never tried an OS plug myself and after seeing them side by side I myself never will try an OS plug. Again I am sure the guys you talk to know what they are doing and if they are the ones that are going to help you if and when you have issues you may want to do what they say. All I am saying is give a hotter RB or Nova plug a try before you start adding shims and using OS plugs.

Chris,

We tried the Novarossi C5TGC plug into the F11, it worked great, no more flameouts. Engine is still tight but it feels so much better now.

Gr Michel