After being open at my new shop, FireHouse Performance at 4502 22nd Ave., Rick Aiello came in and asked me to write an article for Action about bikes or cars. I decided to write this month on the question I get asked the most:

"Do I need to re-jet my Harley If I change the pipes?"

In most cases, the answer is yes due to the fact that when a bike is built it must pass an emission and noise standards punt on Harley by our caring government. Most pipes you buy "after market" will flow a lot more exhaust than the stock prop and will cause a lean condition on the bike. Symptoms of this will be excessively blue pipes, coughing when cold, and long choke use to get the bike to idle. The best way to correct this is to re-jet according to the changes made.

A good rule of thumb is the more air coming in and going out, the more fuel. Most good jet kits will come with a spec sheet for your application. If you have a fuel injected bike; and you do a minor change such as mild pipes, your bike may adjust to it. This is only true if the change you made is in the bike's computer parameter. If you make major changes, such as high-flow air box or a large cam and high compression, the computer will not be able to deliver enough fuel without being reprogrammed or some other form of adjustment is made. Many after market companies have come out with electronic controllers which plug in line with the computers and can be adjusted to your application. The good thing about fuel injection is that it can adjust to small changes, such as temperature or altitude, whereas a carburetor will not.

If you do not fully understand the concept of jetting, it is best to ask or take your bike to a good shop to avoid problems. A good jet kit should cost around $50 A fuel injection control box or reprogram chip will cost around $100 or more. If either change is done properly, your bike should run and sound better than ever.