FMF gold series fatty pipe!!

[Jeannie250R]

Any info on this pipe??

[YFZRob]

Get one! It's awesome and dirt cheap....like $175 at Rocky Mountain ATV. I replaced an ESR TRX5, and the performance improvement on a stock cylinder is amazing. It has a much stronger bottom and mid-range than the ESR pipe. For $175, it's a great buy.

[Jeannie250R]

I know, i got one!!! I havent put it on yet, though! Does it leak at all?? I havent gotten it all the way on yet! It will b on 2night, ill b riding it 2marow!!!!

Do u have any pics of urs. I wana see how urs fits.

[TheFontMaster]

I hear that making the silencer into a shorty will give you alot of power gains on the FMF's.

[TravEX]

I have a shorty Powercore and will trade for a stock length Powercore 1 or 2. My silencer was cut off before I got it, it's about 8 inches long. I just repacked it. It's for an 85-86 ATC.

As for the pipe, I like it ok. I would like to have a Paul Turner High rev on it though.

No they don't leak. I would put new o-rings on the exhaust flange while you have it off.

[bardeenm1]

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1,1&item=4634758361&sspagename=STRK%3AMESE%3AIT

[YFZRob]

I don't have any photos of it yet on my 250R, but the fitment is pretty self explanatory. My FMF pipe didn't include the best instructions, but it is easy to put on.

I have a FMF Turbine Core 2 silencer....needs to be USFS approved for the areas I ride. I originally went to this silencer from an ESR silencer, and I didn't notice any power difference.....that was with my 310 kit too. Just quieter and deeper sounding.

[Jeannie250R]

Ya, i put new o rings on it and a new spark plug!

[Scott-300ex]

I have one.

They give amazing power.

[707trx250r]

What kind of power? Low end , mid , top or just crazy power all over?

[Eddiesanders250]

that pipe isnt designated for a certain power range. Its improvents are all over the power band not a certain area like most pipes.

[Jeannie250R]

mine..........

[baker250r]

FMF and pro circut are generic pipes that give all around power boost.... the other pipes u hear about... LRD, sparks, blah blah are porting specific pipes.

[Jeannie250R]

My uncle was saying some pipes require a rejetting...... The FMF Fatty dont, right??

[YFZRob]

FMF's jetting suggestions are right around stock, but that's for a bone stock bike....stock carb, stock air filter with airbox lid, ect. ect. If you have any other modifications, your motor will require more fuel. I have a stock cylinder with ESR cool head (23cc dome), 38mm Keihin PWK A/S carb, CR250 reed cage, uni filter w/o airbox lid, FMF fatty pipe, FMF turbine core 2 silencer. My jetting is spot on with a 168 main (10 larger than stock), 45 pilot (stock I think), and DDK needle on 3rd clip, which is about 6 needles richer than stock on the chart.

[Jeannie250R]

I have a UNI filter, wat do u think? Is it ok.. or should i get it rejetted?
:confused:

[YFZRob]

It's probably okay, but you should do some plug chops to be safe.

[bardeenm1]

YFZROB is right do some plug chops. remember jetting on even a bone stock bike can be off. Their are so many factors Temperature, altitude, airfilters, exhausts. even when you think you have your jetting spot on it is good to randomly do plug chops just to keep an eye on things. A little prevention goe a long way and is a lot cheaper than a new top end and down riding tiime sucks.

[b.lee]

Originally posted by Jeannie250R
My uncle was saying some pipes require a rejetting...... The FMF Fatty dont, right??

all full exhaust systems require jetting..
main jet and or c-clip position lowered usually does the trick.
sometimes you might need a bigger pilot jet.
or need to mess with the fuel & air screws for fine tuning, not usually though.

do a plug check.

if its white, then you should be looking like this ---> :eek2:
brown/tan is good.
black is too rich on fuel.

[xx3003xrdrxx]

Ive got a shorty FMF fatty. Just had it chopped and reapcked by Rich at hetricks. Real nice power all around , well that and my porting and every other engine mod u can do to an R :devil:

[juanki]

Originally posted by Jeannie250R
My uncle was saying some pipes require a rejetting...... The FMF Fatty dont, right??

i have the fatty pipe and works great for all around, i worked wiyh my mechanic changing the jetting for diferent aplications, when i was on the fast trails, desert like with long roads, i used a bigger jet, think it was 165, then for mx used 145 or 147, something like that. the thing is that you need more gas at high speeds and less when you want to hit hard it the short run.
dont kow if i'm wrong on this one, but thats what i did and worked for me.

[juanki]

have to say that for trails i use 21" front, 22" back klaws, and for mx i use 20" front 18" back holeshots.

dont know if the size of tires have an effect on the jetting, if you have the same jet.

[Jeannie250R]

k,thanx!!! Can u aexplain the plug chops though!! Never heard of that!
:cool:

[86 Quad R]

the process of plug chopping basically involves reading the plugs color to determine whether its running lean or rich on the main jet.

a lean jetting will produce a light color(white to a dark grey) and a rich rich jetting will produce a dark color(dark brown to pitch black)on the plug. ideally you want a honey comb color but i like mine to be a coffee ground color.


any plug chopping should start with a new plug that is properly gapped. (a stock machine calls for a gap of .026 - .028 " but if a R engine has any mods at all that gap needs to be at least .022. irun mine at .018 "), a clean filter, no air leaks in the system at all and your fuel/oil mixed to where your gonna always run it. and if you run the air lid make sure its on.

a plug chop is done in a straight line run at wide open throttle, pulling the clutch and killing the engine at the same time. allowing the quad to coast to a stop. afterwards the plug is removed and then you check the plugs coloring as far down inside the tip of the plug as you can visually see.

if the plug is light in color then ya wanna up the jet size. if the plug is dark then ya want to go down on the jet size. if you've done it as long as i have you'll. this is something that can be done in the feild.

here is a link to some very good ready material for ya.

carb jetting 101 (http://www.duncanracing.com/techfaq/Tech_keihin-carburetion-jetting.phtml)

hope this helps.

[Jeannie250R]

Thanx!

[2StrokeGod]

I have one for sale good condition $150.00 Shiped if anyone is interested.