Is there a secret formula to rejetting?

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Old Guy 54
Tricycles are Cool
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My Bike: 1986 Suzuki Intruder 1400

Is there a secret formula to rejetting?

Post by Old Guy 54 »

I have a 1996 Intruder 1400 with K & N's and cobra drag pipes. I understand rejetting but do not know how much the K&N's change the air in and how much the pipes change the exhaust out. Is there a formula to determine how much these mods change the running of the engine and what percentage fuel needs to be increased to achieve best performance or is it just a trial and error thing? Can this be done with an exhaust gas analyzer? What is the professional way to do this?
1996 Suzuki Intruder 1400

navigator
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Re: Is there a secret formula to rejetting?

Post by navigator »

There is always a degree of trial and error.
But there are certain steps to be taken.

http://www.factorypro.com/tech_tuning_p ... gines.html

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Herb
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Re: Is there a secret formula to rejetting?

Post by Herb »

This is the tire I am using. Over 20,000 miles and still in good shape with no problems.

https://www.yokohamatire.com/tires/avid-envigor
I can't seem to win the lottery. I think I have used up all of my good luck riding motorcycles.

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WintrSol
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Re: Is there a secret formula to rejetting?

Post by WintrSol »

To do it right, you really need a dyno with an exhaust gas analyzer. The mixture will change through the rpm range, so needle jets and jet needles may need changing, along with the main and pilot jets. Or, you could use the rule of thumb provided by factory pro.
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Old Guy 54
Tricycles are Cool
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Joined: Thu Jun 29, 2017 1:34 pm
My Bike: 1986 Suzuki Intruder 1400

Re: Is there a secret formula to rejetting?

Post by Old Guy 54 »

Spoke to the nice folks at Dynojet and was given instructions on my specific bike with all extras. I am installing their kit now. What started all this was a kit from 6Sigma. Their ad said "EVERY Jet Kit Custom Engineered EVERY Time". What a crock of S**t. After I ordered it I got a shipping confirmation in about 30 minutes. I thought wow those engineers are fast. Turns out I get a kit with a bunch of different jets and it turns out it is a try this & if it does not work try this then try this. Ya'll know how much trouble it is to r&r carbs on a 1400. SO do not spend any money with 6Sigma. When I get finished I will post the results. Thanks for all the responses.
1996 Suzuki Intruder 1400

Old Guy 54
Tricycles are Cool
Posts: 5
Joined: Thu Jun 29, 2017 1:34 pm
My Bike: 1986 Suzuki Intruder 1400

Re: Is there a secret formula to rejetting?

Post by Old Guy 54 »

Bike runs great now. Fixed all problems I was having.
1996 Suzuki Intruder 1400

Leckbass
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Re: Is there a secret formula to rejetting?

Post by Leckbass »

Old Guy 54 wrote:Bike runs great now. Fixed all problems I was having.
What are the results?

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Fred
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Re: Is there a secret formula to rejetting?

Post by Fred »

Herb wrote:This is the tire I am using. Over 20,000 miles and still in good shape with no problems.

https://www.yokohamatire.com/tires/avid-envigor

Who the fuck asked about tyres . Its about jetting. :lmao: :lmao:

Lechy
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Re: Is there a secret formula to rejetting?

Post by Lechy »

Fred wrote:
Herb wrote:This is the tire I am using. Over 20,000 miles and still in good shape with no problems.

https://www.yokohamatire.com/tires/avid-envigor

Who the fuck asked about tyres . Its about jetting. :lmao: :lmao:

:lmao: :lmao: :lmao: :lmao: poor old Herb, a day late and a dollar short.
Well spotted.

[emoji41]
Grow old disgracefully young man.

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