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Main Area => General GS500 Discussion => Topic started by: jestercinti on March 28, 2012, 07:12:24 AM

Title: K&N Lunchbox and Stock Exhaust...Is it a bad idea?
Post by: jestercinti on March 28, 2012, 07:12:24 AM
I have heard mixed reviews on this topic, so I'd like some thoughts...

I have a 2009 jetted at 20/60/135 1 washer 3 turns out.  Stock exhaust and a K&N drop-in no restricting air ring.  Runs nice!

I like the increase in linear power compared to stock, and am wondering if the lunchbox filter would help any more?  I like the clean look of the lunchbox too.   Can't do a full Jardine exhaust right now due to funding.

Is it worth it to install the lunchbox with stock exhaust, or is this just wasted money?  Heard it is a pain to tune correctly (Unrestricted air coupled with lots of back pressure).
Title: Re: K&N Lunchbox and Stock Exhaust...Is it a bad idea?
Post by: ruifrsilva on March 28, 2012, 08:50:33 AM
I'm interested in some advice on this too. I just bought my bike and was planning on replacing the stock air filter with a k&n lunchbox and jetting the carbs but would reconsider if its going to be more of a hassle with the stock exhaust than its worth.
Title: Re: K&N Lunchbox and Stock Exhaust...Is it a bad idea?
Post by: reload on March 28, 2012, 09:18:35 AM
i'm running this set up and i'm pretty satisfied with it. it makes it alot easier to access the area for service and gives it just a little extra grunt without the hassle of an obnoxiously loud exhaust.

the trick is in the jetting. it leans out the mixture throughout the range. i went by the jetting for 89-00 carbs and that got me running. then a little fine tuning got it running nice and smooth.

Title: Re: K&N Lunchbox and Stock Exhaust...Is it a bad idea?
Post by: jestercinti on March 28, 2012, 09:34:32 AM
That's what I was thinking (the servicing aspect and cleaning up the area a bit...).  I have already removed the Pulsed Secondary AIR (PAIR) system since there is no emissions check for Southwest Ohio.

I'm a tinkerer so I am always futzing with something on the bike.  I know, if it ain't broke, don't fix it, but that's how I learn.  Beer garage has a jet setting for a 2001+ of  20/62.5/142.5 - 1 washer, 3 turns that I may try at some point : http://beergarage.com/GSJet.aspx
Title: Re: K&N Lunchbox and Stock Exhaust...Is it a bad idea?
Post by: 5thAve on March 28, 2012, 09:38:23 AM
Lots of people running this combination, and I've heard that the jetting is ok. Standard advice is that even stock bikes benefit from a larger pilot jet. Mid and main jets don't usually need to be changed until you put on a freer flowing pipe. The pipe is the restriction in the setup you propose, so maybe put a larger pilot jet, but don't change the others until you decide to change the exhaust. Enjoy!

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Title: Re: K&N Lunchbox and Stock Exhaust...Is it a bad idea?
Post by: reload on March 28, 2012, 09:43:42 AM
its hard to get perfect but it's possible. just use that as a baseline and do some testing of your own. just tinker with one aspect at a time and make sure you're starting with a good set of carbs to begin with. i mean confirm the float height, spring length, orings, gaskets, etc are all in good condition so that you get predictable results with each change.

what i found to be a decent measure was to do idle to redline 1st or 2nd gear pulls. you can do this in any gear but i was on local streets. when i got it in the sweet spot,  the bike just pulled smoothly right up until redline.

it will stutter and bog if you are still lean in any rpm range.
Title: Re: K&N Lunchbox and Stock Exhaust...Is it a bad idea?
Post by: jestercinti on March 28, 2012, 10:16:40 AM
Quote from: 5thAve on March 28, 2012, 09:38:23 AM
Standard advice is that even stock bikes benefit from a larger pilot jet. Mid and main jets don't usually need to be changed until you put on a freer flowing pipe. The pipe is the restriction in the setup you propose, so maybe put a larger pilot jet, but don't change the others until you decide to change the exhaust. Enjoy!


Thanks for the advice.  I am already +1 on the pilot, stock on the mid, and +2 on the main with 1 washer under needle and it runs nice.  May put a Lunchbox on, and tinker from there using the method that reload mentioned.  Bike is a 2009, so my carbs are spotless since I bought it brand new as a last-of-the-last model on the floor in April 2011.
Title: Re: K&N Lunchbox and Stock Exhaust...Is it a bad idea?
Post by: Worm on April 12, 2012, 11:24:57 AM
2005 with Lunchbox and stock exhaust.  20/65/142.5 and 3 turns out. Haven't seen any problems aside from the bike not starting with full choke on. About 3/4 choke and she fires right up. I'm going to keep an eye on my MPG over the next few tanks of gas though to see how fuel economy is affected.
Title: Re: K&N Lunchbox and Stock Exhaust...Is it a bad idea?
Post by: shonole on April 12, 2012, 11:37:13 AM
Quote from: Worm on April 12, 2012, 11:24:57 AM
2005 with Lunchbox and stock exhaust.  20/65/142.5 and 3 turns out. Haven't seen any problems aside from the bike not starting with full choke on. About 3/4 choke and she fires right up. I'm going to keep an eye on my MPG over the next few tanks of gas though to see how fuel economy is affected.

Mine went to shaZam!.  Right around 40.  But part of that is my riding style (and the fact that it's mostly city/short highway rides).
Title: Re: K&N Lunchbox and Stock Exhaust...Is it a bad idea?
Post by: Funderb on April 12, 2012, 04:36:09 PM
when i put my lbox on it was un-drivable with stock jetting, even the stock exhaust, so that should answer the 1st question.... (yes, it will make a difference.)
You will have to rejet with the filter, because more air comes in. more air+more fuel = more power! hooray!
I went the dynojet route, which isnt BAD, its just not as tunable in the future.

The exhaust system makes the sound nicer more than the power. But sound is good too.

Title: Re: K&N Lunchbox and Stock Exhaust...Is it a bad idea?
Post by: jestercinti on April 12, 2012, 05:09:57 PM
Quote from: Funderb on April 12, 2012, 04:36:09 PM
when i put my lbox on it was un-drivable with stock jetting, even the stock exhaust, so that should answer the 1st question.... (yes, it will make a difference.)
You will have to rejet with the filter, because more air comes in. more air+more fuel = more power! hooray!
I went the dynojet route, which isnt BAD, its just not as tunable in the future.

The exhaust system makes the sound nicer more than the power. But sound is good too.

True, I will have to rejet, and have the jets already.  Waiting on the lunchbox to get here from CA via UPS.  It says it will be here tomorrow.  I plan to jet 20/65/142.5.  I have a K&N drop-in now and have it jetted to 20/60/135.  It's nice, but I like the clean look of the lunchbox and also the additional room that I will have without the stock airbox.
Title: Re: K&N Lunchbox and Stock Exhaust...Is it a bad idea?
Post by: Funderb on April 12, 2012, 06:05:05 PM
it is nice to have all that working room when you put in the K&N, i just rejetted my 98 without removing the carbs. talk about convenience. Im not sure how much the old box would have been in the way.

If you replace your float bowl screws with allen key screws you'll be able to change MJs without removing the fuel tank. I dont think mids or pilots are accessible unless you have the perfect length screwdriver. Even then, dont run the risk of stripping a jet. But mains are a cinch!
Just a little food for thought.

I think you will be happy. The economy will drop with the lunchbox, but you'll have just enough added pep to make you happy.
Title: Re: K&N Lunchbox and Stock Exhaust...Is it a bad idea?
Post by: The Buddha on April 12, 2012, 06:22:34 PM
Once someone gets a setup perfect, it can be easily replicated. It is not that bike dependent. Over 200 carb jobs and 500 jet packs pretty much proves that.
Someone says 142.5 works for K&N lunch box and stock pipe, then I'll happily stock it and send it as a pack with the rest of the usual jets and parts.
Cool.
Buddha.

Title: Re: K&N Lunchbox and Stock Exhaust...Is it a bad idea?
Post by: jestercinti on April 13, 2012, 06:08:08 AM
Quote from: The Buddha on April 12, 2012, 06:22:34 PM
Once someone gets a setup perfect, it can be easily replicated. It is not that bike dependent. Over 200 carb jobs and 500 jet packs pretty much proves that.
Someone says 142.5 works for K&N lunch box and stock pipe, then I'll happily stock it and send it as a pack with the rest of the usual jets and parts.
Cool.
Buddha.

I'll let you know what works for me.  Worm says 20/65/142.5 is good with lb and stock exhaust.  I get my lb tonight and will tinker since the wife and kid are out of town.  Looks like a night of wrenching for me  :woohoo:
Title: Re: K&N Lunchbox and Stock Exhaust...Is it a bad idea?
Post by: nmh5028 on April 13, 2012, 08:04:09 AM
I'm running a 2001 with stock exhaust and a Lunchbox filter with 20/65/142.5 and it runs really well. I originally had 62.5 with 2 washers but I think it runs better with the 65
Title: Re: K&N Lunchbox and Stock Exhaust...Is it a bad idea?
Post by: jestercinti on April 13, 2012, 08:14:13 AM
Thanks for all of the replies you guys.  I have the JIS screws out, so it will be a cinch!
Title: Re: K&N Lunchbox and Stock Exhaust...Is it a bad idea?
Post by: The Buddha on April 13, 2012, 08:36:00 AM
Alright kids, I'll order the 142.5 with the parts bimbo. Hope she is sales bimbo soon and my old guys are back @ the parts counter.
Cool.
Buddha.
Title: Re: K&N Lunchbox and Stock Exhaust...Is it a bad idea?
Post by: jestercinti on April 13, 2012, 04:45:52 PM
Just got done jetting and it is perfect!  Will post pics tomorrow.

20/65/142.5 3 turns 1 3mm washer
Title: Re: K&N Lunchbox and Stock Exhaust...Is it a bad idea?
Post by: jestercinti on April 14, 2012, 08:27:12 AM
Completed.  Here are some pics:


Package arrived in the mail today!!!

(http://i1260.photobucket.com/albums/ii569/jestercinti/Package-1.jpg)

No room with the stock airbox:

(http://i1260.photobucket.com/albums/ii569/jestercinti/Before.jpg)

Clean insides ... Well, it is a 2009  ;):

(http://i1260.photobucket.com/albums/ii569/jestercinti/During.jpg)

Here in Ohio, we use what we have to carb tune.  A bit "country" if you ask me.  And Yes, I did complete the Iron Butt 1000 10/2011 on this bike (damn near bone stock).  Must be  :cookoo:.  I did gain respect since everyone else in the group spent some $$ for "comfort".

(http://i1260.photobucket.com/albums/ii569/jestercinti/Tuning-1.jpg)

Jetted 20/65/142.5. 3 turns 3mm washer. Stock exhaust lunchbox air filter.

VERY happy with the resutls.  Sounds Awesome.  Pulls like hell from idle to redline.