Jetting 101 for beginners

[KDXRon]

Jetting 101. Jetting can be tricky to get down and understand 100%. Here is a video I have used in the past, he does a great job of showing how all the circuits overlap, etc. please feel free to add your thoughts and experience. This will help newer riders understand jetting a little better.

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Edited August 21, 2014 by KDXRon

[Bill_P]

My thoughts?  Fuel Injection.  ? ?   I've gotten very lazy the last few years.  My jetting consists of hitting the button and letting the bike idle for 30 sec.  Done.  My other bikes have been a PITA this summer with hot weather, cold weather, humidity, dry weather and 5500 ft altitude.  They run right for a day or two, and then need re-jetting again.  The FI bikes are sweet in that respect though...  ?

Edited August 21, 2014 by Bill_P

[superslyko]

I had a 2001 KTM 300 that was a jetting nightmare.  I could tell a difference in jetting after I simply climbed a hill.  The change in temperature from morning to afternoon was something that was a very serious consideration.  I created a database of what combination of jets were needed for each different riding area I was going to.  I literally had to change the jetting for the altitude I was going to ride.

 

The boys at KTM talk have some jetting Gurus but my bike was so old, the specific #'s they were familiar with had all changed.

 

JD jetting didn't help. Sure it was better, but going to the source made all the difference for me. Sudco International carries a complete tuning range of optional jetting for all Mikuni and Keihin Carburetors. http://www.sudco.com/Carburetor02.html

 

It's all there.

 

After years of trial & error, I became a jetting ACE.  I could tell how a bike was jetted just by it driving by.  I had an "expert" here tell me something completely ridiculous after he heard my bike.  ?   I had to let it go........................................................  he did have some good beer!  ?

 

This 2006 I have now has been wonderful.  I haven't had to mess with the jetting once.

 

I've been told some wonderful things about fuel injection.  I have yet to ride 1.  Soon, oh so soon. 

 

Edited August 21, 2014 by superslyko

[Bill_P]

Sweet Slyko.  My other jetting solution?  Buy a bigger bike.  When riding mammoth, etc. at 8000-9000 ft, ALL the smaller bikes HAD to be re-jetted or they would just barely run.  The 450's, 530's, etc. are a little down on power, but never really seem troubled by the altitude.  We'd run em all week and never bother to rejet.  Can you tell I'm a lazy re-netter?  ?

[superslyko]

Dude,

 

I just talked with my buddy who spent $10,000 for his 450.  AND it costs him $2000 to rebuild that beast. 

 

I could buy 3 of my bike for that and it costs $150 for a piston kit = a new motor with substantially more power.

 

I can't lug this baby @ 2 mph but I don't want to.  I've drag raced a number of 450's and they only beat me in the very end.  In the single track, I'll just walk away from them.  Flick a YZ 250 or a KTM 300 then try to do that on a 530.   ?

 

Folks spend $$$$$$$ for the recluse too.  Now I don't know about you, but I like the clutch!  ?  Climbing a huge obstacle with clutch work has a certain satisfaction attached to it.  I can always buy a trials tire too.

 

I do miss the magic button.  My next bike will have that magic button!  Then the F.I. is next. 

 

I'm kinda a 2-stroke guy.    Oh, the smell of premix in the morning!!!!!!  I just wish I was 21 again. 

Edited August 21, 2014 by superslyko

[Cube Steak]

On the 530 I give my pilot screw a little twist in the hills...  that's about it. 

[MartyrRacer368k]

Some folks know when to buy new tires

[Cube Steak]

What is that ?

[Bill_P]

Dude,

 

I just talked with my buddy who spent $10,000 for his 450.  AND it costs him $2000 to rebuild that beast. 

 

I could buy 3 of my bike for that and it costs $150 for a piston kit = a new motor with substantially more power.

 

I can't lug this baby @ 2 mph but I don't want to.  I've drag raced a number of 450's and they only beat me in the very end.  In the single track, I'll just walk away from them.  Flick a YZ 250 or a KTM 300 then try to do that on a 530.   ?

 

Folks spend $$$$$$$ for the recluse too.  Now I don't know about you, but I like the clutch!  ?  Climbing a huge obstacle with clutch work has a certain satisfaction attached to it.  I can always buy a trials tire too.

 

I do miss the magic button.  My next bike will have that magic button!  Then the F.I. is next. 

 

I'm kinda a 2-stroke guy.    Oh, the smell of premix in the morning!!!!!!  I just wish I was 21 again. 

 

 

That's all cool by me, so don't get your panties all wadded up.  My comment was not to you personally, but instead was a universal...."if you don't like rejetting all the time, buy a FI bike or a bigger cc 4s bike.  And here to think I thought this thread was about jetting, not the cost of bikes, cost of repairs, clutches or how many strokes you got.  Now I'm confused....

 

PS - a 300 or maybe other smoker may be in my future.  I'm freaking sick and TIRED of dragging the big pigs around in the tight stuff, and here, all we have is tight stuff or freeways.  not much in between....

Edited August 21, 2014 by Bill_P

[ElDorado650]

My 650's do fine in the single track

And I never have to mess with the jetting once I got it finished.

Both of my 650's have been to sea level all the way to 10,000 ft.

The run a little lean down low and rich up high - but still run OK.

 

I ran my CR500AF on 33 in Gold Note, and my 650R on the same trail.

I was within 1 minute from each other, on a 40 minute loop.

 

I am getting lazy now with jetting.

Wide band O2 sensor and a meter.

Takes out all the guess work.

[superslyko]

I think that tire is good for 1 more ride!

 

 

 

 

A few years ago I brought my old chain & guide to the dealer when replacing them so I got an exact match..  The oldies were complete trash.................................. the guide's metal housing was worn right through, there was no plastic left. He said, "You like to use parts till they're done!"   ?

 

This bike of mine has about 2 years left in it....................... then I'll have to trash it and get a new one.  When I was a kid I'd buy a new "used" bike every summer, beat the shit outta it, then get a new one next year.    I've since learned I gotta take better care of my shit.  My bikes now last about 4 years till they're done!  ?

 

 

 

 

 

Oh, wait wait wait.  We were talking about jetting!  ?

Edited August 21, 2014 by superslyko

[Cube Steak]

Your buddy spending 10000 on a dirt bike is not a jetting argument maker...  it just shows you got a stupid buddy.

 

This 530 with 2200 miles on it cost me $6000 with everything you see in the picture...  the MOST I ever spent on a dirt bike in my life !

 

[The Anvil]

Your buddy spending 10000 on a dirt bike is not a jetting argument maker...  it just shows you got a stupid buddy.

 

This 530 with 2200 miles on it cost me $6000 with everything you see in the picture...  the MOST I ever spent on a dirt bike in my life !

 

The toolbox looks to be worth that by itself. Good score

[Cube Steak]

No...  the cabinets were the good score. ?

[superslyko]

You guys are outta my league. 

 

[Rich_Bing]

You guys are outta my league. 

 

 

That's a redneck's paradise.

[KDXRon]

10k is a little steep. I bought my 2013 Husaberg for $6,400 out the door (tax, docs, etc). I'm a 2 stroker, I rode a 450x yesterday in the fields and just didn't work for me. As far as jetting is concerned it hasn't been a issue. Most of my riding on this bike is over 5k feet. I run a little lean at sea level and great up in the mountains. A couple turns on the air adjustment and it's perfect. For me, it's the best all around bike. No need to carry jets with me. Now for my YZ.... That's a different story

[The Anvil]

10k is a little steep. I bought my 2013 Husaberg for $6,400 out the door (tax, docs, etc). I'm a 2 stroker, I rode a 450x yesterday in the fields and just didn't work for me. As far as jetting is concerned it hasn't been a issue. Most of my riding on this bike is over 5k feet. I run a little lean at sea level and great up in the mountains. A couple turns on the air adjustment and it's perfect. For me, it's the best all around bike. No need to carry jets with me. Now for my YZ.... That's a different story

That's a steal on that berg! I haven't found any good deals on leftover bergs down south, I've been looking. To me it's the Best looking 2 stroke next to the yz.

[KDXRon]

That's a steal on that berg! I haven't found any good deals on leftover bergs down south, I've been looking. To me it's the Best looking 2 stroke next to the yz.

yeah thanks. Picked it up down south in San Diego. Last one they had. Drove 4 hours to get it.

[The Anvil]

I was up in redding last year visiting my daughter and grandchildren and the dealer up there offered me a berg for 7200-7400 OTD, can't remember which. I thought , it was a great deal but surely SoCal dealers must be cheaper. Wasn't any I could find. Now I'm looking for a decent deal on a used one.

Hell, the 15's are out now, you would look good in orange!