Harley new pipes question any help appreciated!!?

Question

Do I need to rejet the carbs on my Harley low rider if I install new SLIP ON pipes?? If so should I pay to have it done with a dyno or do it myself? Thanks to those motorcycle enthusiasts with answers for me!

Answer 1

What the guy above me said.

Answer 2

You just might have to in order to get the best performance. A dyno can get pricey dut the best option. A good shop could re-jet for ya but without a dyno its sort of geusswork.

If your gonna spring for dyno time ya might as well change out the air cleaner and get your moneys worth. Since your carbed consider an S&S and have the whole set up dynod once.

Good luck, be safe and congrats!

Answer 3

No.

Although, it is a common practice to de-tune bikes at the factory so that they meet emissions requirements.  All new injected HD's can expect a 4-6% increase in horsepower and 2-3% increase in torque just by dyno tuning the bike straight off the showroom floor.

If you're riding a Low with a carb, then you do not need to have it re-jetted for slip-on's.  If you're changing the exhaust from where it bolts to the engine, then yes you should.  Dyno tuning is not as useful on carbureted bikes compared to injected ones, in fact I could tune a carbureted Low just as easily with an Exhaust Gas Analyzer as a dyno and save you $300.

You're probably not that interested in minor differences in horsepower if you're doing slip-ons rather than a whole Screaming Eagle Stage 2 kit.  Bolt 'em on and ride...