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Main Area => General GS500 Discussion => Topic started by: modular on October 07, 2012, 09:14:07 AM

Title: Expected power gains with V&H's full exhaust/K&N lunchbox and re-jet?
Post by: modular on October 07, 2012, 09:14:07 AM
As the title states....what is to be expected?
Title: Re: Expected power gains with V&H's full exhaust/K&N lunchbox and re-jet?
Post by: weedahoe on October 07, 2012, 09:32:29 AM
From what Ive read, not a lot of people around here doing mods and jumping on a dyno so see the results.

A little more power? Sure. A lot? Doubt it.

Better engine breathing in and out and looks better, sounds cooler? Sure
Title: Re: Expected power gains with V&H's full exhaust/K&N lunchbox and re-jet?
Post by: gsJack on October 07, 2012, 09:54:02 AM
About 10% HP increase like Annie's GS, co-founder of this forum.

http://img.photobucket.com/albums/v443/jcp8832/AnniesGS500dynoRun-1.jpg
Title: Re: Expected power gains with V&H's full exhaust/K&N lunchbox and re-jet?
Post by: weedahoe on October 07, 2012, 10:02:02 AM
which equals to 3-5 hp right?
Title: Re: Expected power gains with V&H's full exhaust/K&N lunchbox and re-jet?
Post by: gsJack on October 07, 2012, 10:48:42 AM
That's about it, here's all the published tests I've seen on stock bikes.  Note V&H only claimed about 10% increase on the one they did years ago and they increased the bore and did some port work in addition to the exhaust, intake, and jet mods..

http://img.photobucket.com/albums/v443/jcp8832/GS500tests.jpg
Title: Re: Expected power gains with V&H's full exhaust/K&N lunchbox and re-jet?
Post by: Suzuki Stevo on October 07, 2012, 10:50:12 AM
BONE STOCK '07 GS500F: No other mods, I went one size up on the pilot and the main jets, no washers, 3 turns out on the mixture screws, the bike was way more responsive to throttle input. My point is that all US bikes with carbs have been lean since the 70's, right off the showroom floor to make the EPA happy. So there is untapped power to be found even if you don't add a pipe and K&N, so a 3-5 Hp increase is totally believable , seeing that they need jetting right out of the box.
Title: Re: Expected power gains with V&H's full exhaust/K&N lunchbox and re-jet?
Post by: modular on October 07, 2012, 11:31:11 AM
I just did the stock re-jet (125/40/1 washer/3 turns) and it made a very noticeable difference. It would be nice to feel the change with the pipes/filter/re-jet.
Title: Expected power gains with V&H's full exhaust/K&N lunchbox and re-jet?
Post by: Higgins13 on October 07, 2012, 01:58:31 PM
I literally just did this mod except I used the Jardine system and also sprocket adjustments (larger on back). I love the sound improvements, notice a huge difference on throttle response and a increase in power. The bike itself runs much better and feels much smoother. After adding exhaust and intake I was idiling at over 2200 rpm. I had to lower it back to 1400. That is a strong indication on how much better the bike is breathing. At my first red light with the new mods I wanted to see what it could do. I spun up the tire unintentionally...
Title: Expected power gains with V&H's full exhaust/K&N lunchbox and re-jet?
Post by: Higgins13 on October 07, 2012, 02:00:33 PM
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