| We get the same question all the time "Do I have to rejet or remap if I install an aftermarket exhaust?" The short answer is "Yes". Most bikes are set pretty lean from the factory to meet EPA requirements. Some are worse than others and have a stumble off idle, a weak midrange, etc right from the factory. We just remapped a bone-stock DL650 using the stock ECU (more on that later) and the difference in power delivery was really noticeable.
This goes for both carbs and fuel injecttion. While it's true most bikes with an aftermarket pipe and/or air filter will run
without a mixture change without motor damage (probably), any modification that flows
more air (filter and pipe included) requires more gas to be added to get the
right fuel/air mixture. You can't change just one side of the ratio without
screwing up the resulting final results. It's just simple physics.
Exhaust manufacturers often like to advertise "no jetting required" because it
makes their pipes seem like a better deal because they give the impression that there's no need to
drop $350 on a Power Commander or the like and a couple hundred on labor installing and programming
it. The truth is, you can't avoid the physics, and I'd wager that every employee at those same exhaust manufacturers who rides has their own bike jetted or otherwise kitted to
get the right mixture, just like the rest of us.
If your bike is carbureted, a simple jetting change is all that's needed. If it's fuel injected and not a Suzuki, you'll need to buy an add-on box like a Power Commander or TFI module to allow the fuel injection's ECU to be modified. If you're riding a Suzuki you're in luck, as Suzuki's ECU's are adjustable if you have the right tool.
We have one and have been amazed at the results available with the stock ECU that make spending the additional $250-$350 totally unecessary.
For more info on fuel system mods, emai us at tech@dualsportoutlet.com.
TIP 2: Lowering the Suzuki DR650 Dual Sport | The DR650 has one of the lower standover heights of any dualie and Suzuki has seen fit to include a built-in lowering kit to make it even easier for the height-challenged to get comfortable without buying anything more than a shorter sidestand (which they are happy to provide). Starting with the front more...
TIP 2: The Truth About Oil | The life blood of your motorcycle is the crankcase oil. There are some very important considerations you need to know. First of all, your mantra regarding oil for you bike must be, “It does make a difference which oil you use!” Take your Sharpie and write the mantra on the top of your fuel tank.
Oil rule number one - Never, ever, ever use DELO oil in your motorcycle unless you ride a diesel machine. DELO stands for Diesel Engine Lube Oil… It is designed for slow revving, high carbon, ultra-compression engines. It will not stand up to the high revs created by modern motorcycles. Trust us, we have seen engines that have been subjected to DELO oil because the guy who services it owns a dump truck and buys DELO oil in the 55 gallon drum and swears that it’s the only oil known to mankind and “It’s in all of my rigs…”. Have you ever seen a cam out of a DL650 Suzuki that was subjected to a very aggressive weekend of riding while lubed, or un-lubed, by DELO? Adios top end! DELO is fantastic for the application intended. However, it is not for motorcycles. I know, I know, there are some dirt bikes like the CRF Honda that can tolerate DELO in the clutch because the clutch / tranny lube system is separate from the crankcase lube system. But even in these engines you are courting problems due to the shear properties in DELO. Remember the mantra.
Engine manufacturers give specs on oil. Honor the specs. Some engines are alright with semi-synthetic or even full synthetic oil. Research the oil and your bike before you make changes. Motorcycles often use a wet clutch system. It is called wet clutch because it operates in a “wet” environment – oil. Automobiles with manual transmissions are almost always dry clutch systems. Using a synthetic product in the engine of a car or truck does not involve the clutch as it does in your bike. See how the myth that DELO is great for the engine can cause major problems in a bike? Motorcycles need a clutch to “stick” when activated. If you apply high permeating oil, like some full synthetics, to the clutch it may become too slippery and fail. There are other characteristics that you should understand about lube oil if you are considering a change. Research the following: Viscosity, shear, temperature range, additives and other aspects of oil. Here is a website that can help: http://www.kittiwake.com/5_lube_oil_characteristics.htm
The bottom line is this: Be careful what you put in your engine. Fuel, oil, maintenance schedules, and touch-time all help your bike last for a very long time.
|