Jeting and braking in ????

[dnoftz]

Building a Baster from the ground up. Got the motor done now. But have some questions about braking it in. Here is why. I have a FMF Power Core 2 and A FMF Gold expansion chamber and the carb is stock jetting. So what should I do? Should I brake it in with a stock exhaust? or just go ahead and put the the FMF on it and brake it in and jet it after broke in?

 

[Blaaster]

Fit stock pipe , stock carb.

Do heat cycles and ride for a couple of tanks of fuel at no more than 3/4 throttle.

Re jetting requires WOT to be able to do plug chops.

WOT on a fresh build is not recommended.

 

[EZRider76]

Fit stock pipe , stock carb.

Do heat cycles and ride for a couple of tanks of fuel at no more than 3/4 throttle.

Re jetting requires WOT to be able to do plug chops.

WOT on a fresh build is not recommended.

WOT on new rebuild, in small bursts, isn't a total bad thing, but NOT IN LONG INSTANCES!!! That is the key, WOT on a new build only for short bursts for the first full tank of fuel. The renowned KOR, did a heat cycles video on youtube and someone posted it here, and that is exactly what he recommended...I hear he knows what he is talking about.

However, 3 heat cycles before you ride! Then you want to plug chop for sure to see if you are rich or lean. By what KOR says, you should be able to Plug Chop on a new rebuild because you are only WOT for no more than 10 seconds, just don't run the hell out of it. Once you chop get jetted properly, take a tank or two and take it easy, no WOT for long periods. Then ride it like you stole it. Be smart and research it some more on here, get other's opinions and then formulate your own by educated knowledge.

I will say, Blaaster isn't wrong by any means and he has shared good advice, he will admit he tends to run on the safe side, and there is nothing wrong with being safe. I have only regurgitated what I have read and watched, neither of us would purposely steer you wrong.

 

[blastblast]

That's good stuff just the information I was looking for about my brake in I'll be doing soon

 

[redbabeboy]

what is WOT? and whats a PLUG CHOP?

 

[Triplecrown421]

wide open throttle and look up plug chop

 

[EZRider76]

what is WOT? and whats a PLUG CHOP?

Plug Chopping is warming up your machine, swapping out to a new and properly gapped spark plug(s), starting up and taking off thru the gears to WOT for roughly 6-10 secs, killing the engine, pulling in the clutch and rolling to stop, swap your plugs to the older ones. With the plugs you just pulled out, cutting the threads off and checking the smoke ring (hopefully there is one) near the base of the ceramic of the plug. That is the gist of it, definitely research more for better and more specific details.

 

[Blaaster]

WOT produces great pressure in behind the rings, which in turn are forced to expand outward toward the bore to make a proper seal. The more throttle, the greater the pressure forcing the rings outward.

One of the reasons for heat cycles is to allow the rings to be gently bedded in by the crosshatching of the bore.

Heat cycles are performed with the motor unloaded, therefore the rings will not asked to force themselves very hard toward the crosshatched bore.

Easy throttle openings should now be used to complete the bedding process.

WOT on a fresh crosshatching can produce a fair amount of unessessary ring wear, and 10 seconds is a long time, as there is still a lot of cut left in the hatching

It also produces extreme stress on the piston ring lands, from the rings grabbing at the abrasive cylinder walls.

IMO, a 10 second WOT on a freshly built motor, just out of heat cycles, is a poor idea!

 

[blastblast]

Can you not just use a light and look down the end of the plug and see what color it is? And I was thinking about running 5 heat cycles before riding around on mine is this good or bad idea

 

[Triplecrown421]

honestly dude with a stock carb and fmf system just go between 250 and 270 i run a 270 with my mods and its been the same since mine was like urs. fmf themselves recommends a 270 and imo there bang on. if i were u i wouldent waste time install the fmf buy a 270 (and anything close for later plugchops) and run it. the fmf system will be fine on a rebuild engine aslong as u brake it in properly. i also dont recommend plug chopping with a fresh bore

 

[EZRider76]

You don't HAVE to hold WOT for 10 seconds for a plug chop, that is a misconception. You just need to hold WOT until you max out rpms. You don't even need to be in 6th gear, you can do it in 4th if you only have that much room. Argue all you want, a friend of mine showed me on his Quadzilla, 4th gear, WOT maybe 4 seconds (1/4 acre of land)...pulled the plug and he had a rich looking ring on his plug.

Blastblast, you can look down in there and get an idea, but to know for sure, chop the threads. B8ES plugs are $2 a piece.

 

[Blaaster]

Aggreed that a WOT for a plug chop can be done in 4 th gear. and for 4 seconds. The idea is to get the motor to pull at full load, for as long as possible the max being 10 secs, which makes for better reading.

My concern is that we are dealing with a fresh build motor on which jetting has not been confirmed with an FMF pipe.

One can so easily run just a little on the lean side, over heat the piston crown, expand the ring lands, pinch a ring, and then consequently snag a port with the pinched ring.

One can assume that the stock pipe and a #230 main should be a safe bet.

My way to break in would to be to use the stock setup, and then when broken in to the owners satisfaction, fit the FMF and re jet, confirming with plug chops.

If you do go the way of breaking in with the FMF, put in a #280 and plug chop it there, and work backward to confirm.

Not all motors breathe the same!

as EZRider76 says, I always play on the safe side, and I have not been embarrased yet.

 

[EZRider76]

Aggreed that a WOT for a plug chop can be done in 4 th gear. and for 4 seconds. The idea is to get the motor to pull at full load, for as long as possible the max being 10 secs, which makes for better reading.

My concern is that we are dealing with a fresh build motor on which jetting has not been confirmed with an FMF pipe.

One can so easily run just a little on the lean side, over heat the piston crown, expand the ring lands, pinch a ring, and then consequently snag a port with the pinched ring.

One can assume that the stock pipe and a #230 main should be a safe bet.

My way to break in would to be to use the stock setup, and then when broken in to the owners satisfaction, fit the FMF and re jet, confirming with plug chops.

If you do go the way of breaking in with the FMF, put in a #280 and plug chop it there, and work backward to confirm.

Not all motors breathe the same!

as EZRider76 says, I always play on the safe side, and I have not been embarrased yet.

Yeah, I'll say, listen to Blaaster. He may be from across the pond, but he's pretty wise and would never steer anyone into spending more money or ruining their ride. Mount up the stocks and play it safe for now, learn our FMF system after you know the engine is good to go.

Here is that break in heat cycles video from KOR...
Engine Break In - YouTube

 

[Triplecrown421]

You don't HAVE to hold WOT for 10 seconds for a plug chop, that is a misconception. You just need to hold WOT until you max out rpms. You don't even need to be in 6th gear, you can do it in 4th if you only have that much room. Argue all you want, a friend of mine showed me on his Quadzilla, 4th gear, WOT maybe 4 seconds (1/4 acre of land)...pulled the plug and he had a rich looking ring on his plug.

Blastblast, you can look down in there and get an idea, but to know for sure, chop the threads. B8ES plugs are $2 a piece.

two different worlds dude 1 were talkin blasters no quadzillas to relate to. and b8es plugs are almost 5 bucks a piece here before tax i would be plug choppin every morning for 2 bucks a piece

 

[Blaaster]

A 2 stroke, is a 2 stroke, and a plug chop, is a plug chop, no matter wether it is on a Blaster, Banshee Quadzilla or an IT400, the plug chop sequence is the same, as well as the tell-tale smoke ring colour.

Plug chops are a nessesary tool for 2 strokes, to make the jetting is correct.

 

[Triplecrown421]

A 2 stroke, is a 2 stroke, and a plug chop, is a plug chop, no matter wether it is on a Blaster, Banshee Quadzilla or an IT400, the plug chop sequence is the same, as well as the tell-tale smoke ring colour.

Plug chops are a nessesary tool for 2 strokes, to make the jetting is correct.

i guess thats true i might have been close with my plug chop but i noticed if i dident give it a good wot run you wouldnt even notice any colour change in the plug. i found i had to give it a good stretch on a long sreiaght to really notice where i was on the plug

 

[EZRider76]

i guess thats true i might have been close with my plug chop but i noticed if i dident give it a good wot run you wouldnt even notice any colour change in the plug. i found i had to give it a good stretch on a long sreiaght to really notice where i was on the plug

I've noticed I don't get much color on a short run either. The guys at the local shop told me they find it is hard to get a stain on the B8ES in such a short run, but the guys on here seem to get one every time....something may be fishy.

As for $5 a plug, guess you could say that is equivalent of our price per gallon of gas vs. your price per liter of gas. Either way, that sucks.