jettting for KOR ported vitos 240

[bonedust]

hello fellow blaster riders.
need some help. I just ordered vitos bb with KOR porting and need a starting point for jetting. LRD pipe and silencer, open airbox, premix 32:1, at 1800 ft elevation and will be using mikuni 38mm TMX carb (because I have one sitting around). What main and pilot jet should I start out with. Thanks in advance cause I know some of you blasters know and understand your ride better than life itself.

 

[Wifesblaster]

hello fellow blaster riders.
need some help. I just ordered vitos bb with KOR porting and need a starting point for jetting. LRD pipe and silencer, open airbox, premix 32:1, at 1800 ft elevation and will be using mikuni 38mm TMX carb (because I have one sitting around). What main and pilot jet should I start out with. Thanks in advance cause I know some of you blasters know and understand your ride better than life itself.

I would call ken. He's a mikuni man and knows his work. 38 might be a bit to big though. Give ken a call he will get you close.

 

[Awk08]

most suggest, and run, no more than a 35/36mm carb for the 240bbk. and mostly keihins at that.
expect a loss of bottom end with that big of a carb.

here's the only detailed info i know of on here for a 35mm mikuni, and it's on a 200cc cylinder .........

http://www.blasterforum.com/engine-parts-151/mikuni-tm-carburetor-review-43253/

i'd look to see what stock jetting is on any of the 250cc dirtbikes that have run that carb.
or....
call the dude at carb parts warehouse, he may have some guidence for you.......

http://www.carbparts.com/

check the mikuni section on there, there is some general jetting numbers for each make/model carb

 

[bonedust]

my 38mm is from my 2001 yz125. if it runs good in a 125cc why not for 240cc? I may buy 34mm or 36mm as you guys know best. where can i buy reed boots to fit a 34 or 36?

 

[Herpderplol]

LRD !!!!!!!!!! I have a friend!!!

I have a 35mm mikuni if you are interested....

Shoot me a pm when you can

38mm is just too big for a blasty I:I


Word of advice for the LRD:
Get a screw gun with a wire brush wheel on it, and clean where they slide together VERY good
Use more sealant than you think, and add extra on the bottom of the adjustable spot
Put the sealent in the muffler pipe and slide onto the pipe, it creates a little ring inside and helps prevent leaks 20 times better I:I

 

[Blaaster]

38mm is an overkill and will loose so much down low power.

A 125cc motor can handle the larger carb as it is designed to rev much higher than the Blasty 200 cc.

 

[Awk08]

alot of the dirtbikes running those massive carbs are also
power valve engines.
port layout, stroke vs. bore prolly, and the pipe design also play a role ?

and the question is....where can you find a 38mm intake for a blaster ???

here's the 34-36mm models....
UPP Racing Intake Manifold 34 35mm Black 1129 Yamaha YFS200 Blaster 88 06 | eBay

Moose Intake Manifold Fits Yamaha YFS200 Blaster 88 05 w 34 35mm Carburetor | eBay

 

[Wifesblaster]

alot of the dirtbikes running those massive carbs are also
power valve engines.
port layout, stroke vs. bore prolly, and the pipe design also play a role ?

and the question is....where can you find a 38mm intake for a blaster ???

here's the 34-36mm models....
UPP Racing Intake Manifold 34 35mm Black 1129 Yamaha YFS200 Blaster 88 06 | eBay

Moose Intake Manifold Fits Yamaha YFS200 Blaster 88 05 w 34 35mm Carburetor | eBay

The one place that comes to mind on a 38mm intake is CT racing. They offer their kit with a 38mm carb.

 

[Awk08]

The one place that comes to mind on a 38mm intake is CT racing. They offer their kit with a 38mm carb.

that is correct I:I

 

[bonedust]

You guys are the best..real helpful and giving me links too. Just ordered pj 34mm keihin and boot. So let me ask is an LRD pipe system good? The only thing left for me to do is figure out jetting.

 

[Wifesblaster]

You guys are the best..real helpful and giving me links too. Just ordered pj 34mm keihin and boot. So let me ask is an LRD pipe system good? The only thing left for me to do is figure out jetting.

I can get you close with the pj34. You will be around a 55 pilot and 155-160 main. Use a dgh needle in middle slot, adjust from there.

 

[Herpderplol]

You guys are the best..real helpful and giving me links too. Just ordered pj 34mm keihin and boot. So let me ask is an LRD pipe system good? The only thing left for me to do is figure out jetting.

Absolutely not... THEY ARE AWESOME!!!!!


I bought mine with a DG and i knew it lacked power....
I got my LRD, i have it adjusted to about half length, and i almost lost the handlebars when it hit the powerband and the sweet spot in the pipe I:I

Although, i think LRD is the hardest to get on the blaster...

Awk told me a secret.... Make it as short as it goes, take off the flange and you can twist it into the frame without taking it apart.
And after sealing mine 3 times, i learn another trick that will help you... Put sealant on both pieces of the pipe and slide then together, then smooth it out with you finger. (brake parts cleaner will take the copper sealant stuff right off your hand )

Also, take a steel brush thing on a drill and get a face mask and clean the pipe connections VERY well.... That was my main problem when i sealed mine...

Here is mine sealed:




Here is a good wire brush:
(No thats not the drill i use.... i had to use that one because our good ones are out in ND with my dad I:I)