Jetting question

[drumike102]

So just bought an sxr and the guy before me had a dry pipe on there and changed jets but didn't change them back when he took off the pipe. He said it should be fine. Is this true. Only mods it has now timing advance plate and pump cone.

 

[Shonuff]

No, it will be way too rich for your stock setup.

Return it to stock unless you have aftermarket arrestors or the trumpets pulled.

 

[drumike102]

what do you reccomend? I don't really want to mess with the carbs. I was looking into arrestors but they seem a bit pricey for just a filter.

 

[Shonuff]

75 and 132.5 with 1.8 needle and seat and 80g springs

 

[drumike102]

haha i wish i knew what that meant. I'm way to new to this. Is it hard to reget the carbs? Do I have to remove the carbs?

 

[Shonuff]

No and yes.

Take the carbs off (4 bolts)
Take the fuel pump covers off (4 screws each)
Take the metering blocks off (2 screws that you'll probably strip)
Rejet
Reinstall
Easy as pie.

 

[chriselmore_1]

Take you 10 mins. Search mikuni manual. It might even be in the tech section. Itll tell you everything you need to know. There might even be in a rejetting thread there he i remember correctly

 

[Shonuff]

http://www.drmikesandy.com/X-H20/Mikuni SBN Manual.pdf

http://www.drmikesandy.com/X-H20/Mikuni Rebuild.pdf

 

[drumike102]

ok i think i might have to get my hands dirty. Doesnt sound too bad. Where can i get the stock jets. He didnt give them to me when I bought it. Sorry for all the questions. you guys are being super helpful I cant thank you enough!!

 

[Shonuff]

Five bucks apiece at Watcon.com.

http://www.watcon.com/Catalog_Pages/Carb_Jets.htm

$2.50 apiece at Atlantic Jet Sports

http://www.atlanticjetsports.com/jetting.htm

 

[Shonuff]

By the way, the 75 is the low speed, 132.5 is the high speed jet.

 

[drumike102]

do i need the needle and seat or the spring? would those have been changed when he jetted for the pipe?

 

[Shonuff]

Stock is 1.5 and I bet that's what you have.

 

[drumike102]

so what if I decide to switch to some K&N flame arrestors would I have to rejet again?

 

[Proformance1]

Word to the wise, use the correct size screwdrivers to do the job, and hit the screwdriver with a hammer before removing. Every set of carbs I get I have to cahnge the screws cause someone else already stripped the heads.

 

[Shonuff]

so what if I decide to switch to some K&N flame arrestors would I have to rejet again?

No, the 75 pilot will cover you should you make the change.

 

[drumike102]

well i decided and bought some k&n flame arrestors so should I leave the jets hes got in there or switch to stock? I believe he has the 80 low speed and 152.5 high speed in there that factory pipe recomends

 

[Shonuff]

You're still waaaaaaaay too rich with that setup. Sorry dude, looks like your hands will smell like gas pretty soon.

 

[Proformance1]

The Dry pipe jetting will be incorrect unless you run a pipe. With stock exh and just K&N flame arrestors, stock jets may be fine but you will have to turn up the screws from the stock location.
If you dont know what you are doing get a friend that can help, as I take no responsibility for the info given below.
The jets below should be fine but the high and or low speed settings will most like be higher with you specific application. Also if the choke plates are removed you may need more fuel than this setting also. 152.5 and 80 are the jets for the wet pipe, I am not sure if they are the same for a dry pipe.

Here was the stock setting for the SXR:
Main Jet 132.5
Pilot Jet 72.5
High speed screw approx 3/4
Low speed screw approx 7/8
Needle/Seat I think 1.5 or 2
Spring 80 gram
Pop off 38 psi

 

[drumike102]

haha ok thanks for the info guys. ordering me up some jets. I took the airbox off yesterday it doesnt look too bad.