Rejetting 2nd Gen????

[Gold Rush]

OK, I've removed my carbs because the intake manifolds are getting huge cracks. Earlier someone had mentioned these cracks would be cosmetic only because the intakes had metal sleeves in the core. NOT MINE!! Some of these cracks actually only tissue paper thickness from breaking through. Boy am I glad I pulled the carbs.. But that's getting sidetracked..... :whistling:

 

I've read the tech pages and a few of the threads regarding rejetting. There seems to be some cloudy areas and I really don't want to go through this more then one time... :confused07:

 

In the tech pages I'm getting the impression Don is saying changing the main jets isn't gonna help that only the pilot jet needs to be replaced. Is that what the general feeling is now?

 

In one of the threads someone mentioned they got negative results from shimming the needles. Can anyone shed better light on this?

 

Is modifying the air intake still recommended? If so, can someone point me to "HOW TO"? Pictures might be nice here also...

 

Well I guess that's about it. Thanks in advance for any help...

[Squidley]

I was helped by Denden with my carbs as I replaced the intake boots on my '99. Now my application is a bit different and I have drilled out Roadking mufflers and K&N filters. We ended up replacing all the jets in the carbs to fatten up the fuel mixture.

 

I dont know what all you have done to your bike, but perhaps rejetting the carbs will work better for you. I was talking with Dennis and he had mentioned about not shimming the needles, and I totally trust his judgement. He is one of the few folks on this site that when tech stuff is mentioned he is a guru.

 

I know others will chime in here, but watching Dennis do my carbs I realised it wasn't as terrible a job as I thought. Folks will help you iron out this out with you

[BOO]

OK, I've removed my carbs because the intake manifolds are getting huge cracks. Earlier someone had mentioned these cracks would be cosmetic only because the intakes had metal sleeves in the core. NOT MINE!! Some of these cracks actually only tissue paper thickness from breaking through. Boy am I glad I pulled the carbs.. But that's getting sidetracked..... :whistling:

 

I've read the tech pages and a few of the threads regarding rejetting. There seems to be some cloudy areas and I really don't want to go through this more then one time... :confused07:

 

From the article I read it doesn't sound like you need to rejetl. I have K and N filters and HD mufflers drilled out straight through and the bike runs fine.

 

In the tech pages I'm getting the impression Don is saying changing the main jets isn't gonna help that only the pilot jet needs to be replaced. Is that what the general feeling is now?

 

In one of the threads someone mentioned they got negative results from shimming the needles. Can anyone shed better light on this?

 

I have shimmed the needles and it helps the idle, shimming does not change things a lot and only change the overall running very slightly.

 

Is modifying the air intake still recommended? If so, can someone point me to "HOW TO"? Pictures might be nice here also...

 

If you are talking about drilling holes in the air boxes I haven't done that and found no need to.

 

Well I guess that's about it. Thanks in advance for any help...

 

Good Luck,

Jerry

[Guest KitCarson]

Ignore all of us.......Contact Denden........each situation is different, none are the same......I feel you do not need to re-jet, and even if you do it is a sometimes it works, sometimes it don,t type of thing........with air/fuel mix the pilot jets are the key......but like I said.....talk to Denden, he is very knowledgeable about this kind of thing. Some of the rest of us think we know, but do not:rotfl::rotfl:You can listen to Denden. Just like the comment the intakes have metal sleeves in them.......gee never seen that either.............

[Denden]

OK, I've removed my carbs because the intake manifolds are getting huge cracks. Earlier someone had mentioned these cracks would be cosmetic only because the intakes had metal sleeves in the core. NOT MINE!! Some of these cracks actually only tissue paper thickness from breaking through.

I think it's just the 1st gen's that have a metal sleeve inside the rubber boot. I never checked the 2nd gen, I guess Yamaha saving money.

 

 

In the tech pages I'm getting the impression Don is saying changing the main jets isn't gonna help that only the pilot jet needs to be replaced. Is that what the general feeling is now?

It depends on which mufflers you have. If you have stock mufflers, then, yes, just replace the pilot jets...stock is #15, replace with #17.5 for more low end torque and throttle response. If you have free flowing mufflers, like drilled out Road King, or Bub's, or Baron's...It's not necessary to re-jet, but if you do, you can get better power and torque.

 

In one of the threads someone mentioned they got negative results from shimming the needles. Can anyone shed better light on this?

I tried shimming the needles after re-jetting, not much change except a little lower gas mileage.

 

Is modifying the air intake still recommended? If so, can someone point me to "HOW TO"? Pictures might be nice here also...

It depends...stock mufflers and jets, not good for power, but might get you more mpg (MIGHT). If you have free flowing mufflers and K&N airfilter and re-jetted main and pilot...if you don't modify the airbox you get more low end torque and a little less mpg. If you modify the airbox (make the enter hole bigger than the exit hole, use a dremel), you get more high rev HP, a little less low end torque than if you didn't, and gas mileage would be pretty close to what it was stock. Well, that's the way it was with my '01 RSV. I had 2 sets of airboxes, one stock for around town (fun), one opened up for long trips (for better mpg). They are not too expensive, and easy to change.

[Gold Rush]

Thanks for jumping in there Denden... I've sent you an e-mail but you don't need to respond now. Unless you just want to say "HOWDY"..:smile5:

 

I really appreciate the help. Guess I'll be ordering main and pilot jets.. :whistling:

[Sleeperhawk]

Right now I have stock all expect for the new Khrome Werks. Gas mileage has not dropped off, but I would like better mileage. Currently getting around 37 at 60 and 30 at 75. mostly two up, so what can I do to get better mileage, cut holes in the covers where?

[Gold Rush]

OK -- I went and looked at the air boxes. I'm guessing you are speaking of the ones the filter goes in.... :whistling:

 

Is the opening up front where the air comes in what gets enlarged? If so how much... A person could carve quite a bit of plastic out of there... I don't see any other place to do any carving so I sure hope that is the place.. :confused07::confused07:

 

Thanks!!!!!!

[pegscraper]

The basic construction of the intake boots is the same for both 1st and 2nd gens. There is an aluminum core inside the rubber, but it's not visible from either the inside or the outside. It can be seen from the the underside of the base, and that's it. But it extends 2/3 the way up inside the boot. A line of cracks will usually appear first in the area of the top of that aluminum core. Cracks on the outside may or may not go all the way through. The boots will generally last a long time even after cracks appear on the outside.

[Denden]

OK -- I went and looked at the air boxes. I'm guessing you are speaking of the ones the filter goes in.... :whistling:

 

Is the opening up front where the air comes in what gets enlarged? If so how much... A person could carve quite a bit of plastic out of there... I don't see any other place to do any carving so I sure hope that is the place.. :confused07::confused07:

 

Thanks!!!!!!

Yep, you're in the right place. If you measure the inside diameter of the hole where the air goes "in", you will find that it is smaller than where the air goes "out" into the rubber tube that connects to the airboxes. If you make the "in" hole bigger than the "out" hole, you will have less restriction (at high rpm's). Some guys removed enough material to make the hole a "D". My personal opinion...just making the "in" hole bigger than the "out " hole is going to make it less restrictive. By the way, the Yamaha parts list says that part is a "silencer". I think they made it that way to eliminate induction noise. I didn't notice any difference, but my mufflers get pretty loud when I crank the throttle, so I doubt that I would be able to hear the carbs sucking air.

[Gold Rush]

Glad to see I stumbled into the right place.. Really, as I said earlier, there just wasn't any other place I could find... :whistling:

 

Thank You for the help... I'll let you know how this all works out.... :thumbsup2:

[AmnChode]

So, if you have free flowing mufflers and K&N airfilter, is there still a need to rejet? Or, is it just the mufflers that I can get away with?

[Denden]

So, if you have free flowing mufflers and K&N airfilter, is there still a need to rejet? Or, is it just the mufflers that I can get away with?

You don't HAVE to re-jet, it will run fine. Many Ventureriders do it that way (don't re-jet). But if you choose to re-jet, you can get some better performance.

[Snarley Bill]

OK, I've removed my carbs because the intake manifolds are getting huge cracks. Earlier someone had mentioned these cracks would be cosmetic only because the intakes had metal sleeves in the core. NOT MINE!! Some of these cracks actually only tissue paper thickness from breaking through. Boy am I glad I pulled the carbs.. But that's getting sidetracked..... :whistling:

 

I've read the tech pages and a few of the threads regarding rejetting. There seems to be some cloudy areas and I really don't want to go through this more then one time... :confused07:

 

In the tech pages I'm getting the impression Don is saying changing the main jets isn't gonna help that only the pilot jet needs to be replaced. Is that what the general feeling is now?

 

In one of the threads someone mentioned they got negative results from shimming the needles. Can anyone shed better light on this?

 

Is modifying the air intake still recommended? If so, can someone point me to "HOW TO"? Pictures might be nice here also...

 

Well I guess that's about it. Thanks in advance for any help...

i drilled out my primary or pilot jets and left the main jets and metering rods alone.since it's already rich in that area from the factory,and i did'nt have the right size drill when i had the carbs off. with the 7500 rev limit i need more fuel over 5000 rpm for max power ,but it still runs solid.got baron bag slashers with my own design baffles,dyna 3000 on 3,and billet aircleaner with k&ns.it is one bad mama,rev limiter at 7500.the dyna 3000 will give you the most bang for the buck. the pilot jets are a freebee and give lots more lowend and mid range.mine could use a little more fuel on the top end with the mods i got,just never had time to get back in there.not what i consider fast but runs awful good for a 900 lb. bike.so far la is the only one that has got to me on his 1rst gen.i short shifted to 2nd gear before we took off.got caught with my pants down.we will hit it again one of these days.not making excuses if your listening la you got me fair and square. lol. if i remember right la said we quit about 94 mph according to his gps and he had about three bikes on me.with the mods i got and the big pilot jets you have to stay awake for the shift to second.it bangs the rev limiter so fast in low gear at 7500 rpm by my tach you think something is wrong. bill

[AmnChode]

You don't HAVE to re-jet, it will run fine. Many Ventureriders do it that way (don't re-jet). But if you choose to re-jet, you can get some better performance.

 

Cool beans....Just got my bike and planning projects, just didn't want it running too lean. Thanks for the quick reply...