no probs

try it won't do it any harm..depend on what setup you like..and try a slightly colder plug as the hiked compression is harder on plugs..

I'm experimenting..in my experience the really hot plugs have so thin a wire they can break under higher compression..but ran it with a p5 yesterday and it liked that ok..

Hey guys what glow plug , short , stander plug fits the 3 port sport motor??

Short Os. style. A standard with 2 washers will work also.


Rex

are these engines bad for slinging rods, my 5 port was running good in quals till it slung a rod through the block and a friend slung 2, is there a diff rod that will fit

i'm sure 22Racer will back me up on this, i've been told to change the rod and bearings at 2 gallons and they will last forever...atleast mine have so far

Yep. As anyone who has broken in a new Pro series motor will know, these things are notriously tight out of the box.
Even if you follow the recommended break in procedure used by most of the guys on this forum (foiled head heat cycle method), because the pinch is so great when these motors are new, some strain to the con rod is unavoidable.
Thats why it is recommended you change the rod at around 1.5 to 2 gallons when the majority of the pinch has gone. That way you are not pulling huge revs later in the engines life with a possibly weakened con rod in there. The rods are only a few dollars, so it's a no brainer really
I have changed the rod in all my GO motors at the 1.5 gallon mark and two of them (a 5 and a 7 port) have been running for nearly two seasons without a hint of trouble. However regular maintenence including after-run oil and bearing changes when required are all part of the deal. In a tiny motor making that much power, regular strip downs and inspection / replacement of parts is the norm if you want trouble free running. It's the same with any nitro motor - if you just race it, and never check the internals then you are going to be buying a new motor sooner rather than later

I'm on tank 4 of break-in and all I can say is WOW. I've never seen an engine that tight. I don't see how it's possible to bump this engine without preheating. It was giving my starter box a run for it's money

I will absolutely be changing the conrod (probably wristpin and clips too)at 1.5 gallons. I'll also go to ceramic bearings at 3 gallons. I'm gonna love this engine. I want it around for awhile. (Go Tech .25)

I'm following the MG66 as well. I'd like to use it in my 8T if the .25 turns out to be overkill. I'm more of a momentum driver so I'd prefer a .21 but our two local club tracks are loamy, old-school tracks. We'll see.

I would say most rods broken needed to be changed or engine wasn't broken in with the motor hot enough or took too long to get it going for break in.
I break mine in on a Hudy bench and get them 240 deg. I charge $30.00 for break in but it sure does save headaches for some guy's.
I have motors with over 8 gallons on them that I've only changed the rod once, every time I take one apart I use a bore guage to measure wear and only replace them when they start to show wear. I have had probably 8-10 Go's and broken only 1 rod. When I resize sleeve's I also let them know how much wear there is in the rod.

Rex

I think spending the extra thirty dollars extra
to get a new GO Engine right off of the break-in
bench is a great deal. Like you said Rex, it will
help save them the pain of breaking the initial
pinch.
Another thing, for everyone here in the U.S. that
are waiting for the new line of GO engines. You should
think about buying them from someone who offers
break-in service, does engine repair, engine modding
sleeve re-sizing, is a machinist with his own shop and is
an authorized GO Engines Dealer. Your not going to get
much help or service buying from one of the big on-line
rc stores.

Does anyone make "unpinch" tools yet? A cylinder hone or some other more precise tool might be useful with these Pro engines.

When I added the break-in shim to my new .25 I rolled the piston up the cylinder. It started to pinch pretty far down the cylinder. It shocked me a bit even after considering the button. Break-in just seems harder on the engine than it needs to be.

*shrug* Oh well...I love a good challenge. It's totally worth the pain

It's actually not harder than with any other engine out there. There are certain design approaches that GO has made and formed a very competitive engine lineup. In most cases guys just don't listen what they are being told to nor disregard the info and then blame on the gear if it fails.

Be it the GEN 5/5.5 or the new GX series engines, just do the basic steps:

Install run-in shimm
Put in hot plug (like OS P3)
HEAT the engine to +100degC meaning BOTH the heatsink and block is in +100degC
Loosen the plug
Prime the engine
Start it
Fasten plug
If engine tends to stall screw in LSN 1/4 turn and that should do the trick

It's not difficult and in most cases people dont really heat engine enough (use hair dryers or something crap), don't have starter box batteries fully charged or the car is not aligned correctly so the wheel touches chassis or something stupid like that.

When speaking of the con.rod stress. I think atleast 9/10 reason for rod giving up is that the user has not made sure the engine stays in +100degC when running in. If done properly you don't have problems with rods and for all racers it should be normal to change the rod anyway when the engine has bedded in. It's not a cost issue as you already have saved a lot by not buying a "high end mill" for nothing and considering the Go spare prices it's really not a issue to anyone. People are just so lazy and it's easier to blame on the engine than yourself not maintaining it.

Agreed. For what it's worth, I preheat mine to 200 degrees Fahrenheit before turning it over. You still need a good starter box though. I'm considering having some stickers made that say "PREHEAT TO 200 DEGREES DURING BREAK IN."

Also, TAKE YOUR TIME.

Guys... things are moving along, and I have some big things in store for 2010. Factory shipment should go out Friday or Monday. Depends on how long it takes for the wire to go overseas. Parts (conrods, sleeves, rebuilds, clips, oh my!) will go out shortly after that, once payment is received. If your dealer doesnt have something ASK!!! I'm building up inventory, but demand keeps growing. This is a GREAT thing to have. Please be assured that I will be reinvesting into subsequent orders. I hope to have lead times on orders for the first couple of months no longer than 2 weeks for anything I may not have in stock at the time. However, I'm going to be repurchasing the parts that are in higher demand, first.

Dealers... if you're interested, I'm working with Citibusiness regarding credit lines. If you need this, please feel free to ask and I will arrange for the documents to be sent. Please keep in mind that this is handled entirely by citibank.

Still having an issue with the 5 port. Rex and I have done a few things with no avail. I have a tremendous lean bog on the low. I recently put a carb from my RB s7II on it with the same results.

yes thats common, this motor had 3gal on and recently new bearings and con rod was new, it was original crank but showed almost no wear only 3gal. i do heat cycle for break ins, and preheat before starts for about 1/2 gal afterwards. i did have a lightweight flywheel on it, might have over revved it.