Questions & Answers

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Hi-Ho Silverado
Q I purchased a Yamaha 650 Silverado two months ago and just last month had the dealer install V&H; slip-ons as part of the deal. I was told that the 650 probably would not need jetting, but if it began to run differently to bring it in for the work to the carbs. I have noticed that my mileage has dropped about 4-5 mpg, however. Would this drop be due to the cooler weather, a richer mixture or both? So far the motor is very smooth and responsive and idles just fine with about thirteen hundred miles on the new exhaust system. Lastly, because the pipes/service is being done by the dealer will the manufacturers' warranty cover such changes? (The dealer is a Yamaha dealership).
Terry Phelps
Seneca, SC

A Typically a less restrictive exhaust will create a lean condition so it's improbable, though not impossible, that your bike is running richer due to the pipes. By the same token because cool air contains more oxygen, a drop in temperature also tends to lean the mixture out slightly, so again it's doubtful that a drop in temperature has affected your mileage for the worse. Exactly why you've lost mileage is open to conjecture, it maybe something as simple as a change in riding habits, but without more info all I can do is guess.

As to your second question, no, the jetting wouldn't be covered under warranty. The pipes are an aftermarket accessory product that you've had installed. Your warranty only covers defects in OEM parts and workmanship. The cost of having the bike jetted will come out of your pocket.

Short and not so sweet
Q Any hints for how a short rider can safely handle a tall motorcycle? I traded in my H-D cruiser for a Triumph Tiger. It is a magnificent bike, but I have a 29 inch inseam and it has a 32.8 inch seat height. I dropped the bike once, had several close calls during slow speed maneuvers and will not feel safe carrying a passenger until I gain more skill and confidence controlling the bike.
Harry Simonsen
Via email

A The easiest way would be to fit a shorter seat, and if I'm not mistaken Triumph does offer one for that model. However I doubt that's going to get you where you need to be. The quick and dirty method would be to slide the forks up in their clamps and install a shorter rear shock. I'll go out on a limb here and say you can probably raise the forks by an inch and shorten the rear shock by the same amount without running into any problems. You should consult your Triumph dealer just to make certain. If there's not enough room to slide the forks up you can have a specialist like Race Tech shorten the forks, (they can probably shorten the rear shock as well, which might be cheaper than buying a new one.) Lastly I should mention that both ends of the bike need to lowered at the same time and by the same amount. Trying to lower only one end of the bike can create some real handling problems.

Gas crisis
Q Last June I took a trip to Tennessee from Texas. On the third day out, my 99 Honda Valkyrie sputtered and died. It was similar to running out of gas. I pulled to the side of the road and checked the usual suspects and found nothing. After cranking it a couple of times the bike started and I rode away without any further mishap. During the next two days it happened two more times exactly like the first time. I figured it was bad gas. Since then I've rode to west Texas and New Mexico without incident. This past Sunday while riding locally it did it again. The same scenario. Got any idea where I should look? Oh, prior to the Tennessee trip the bike underwent a major service at my dealer, which included a carb sync.
Frank Ingram
Via email

A The first thing I'd do is change the fuel filter, after that check the fuel pump pressure and its connections, I've seen lots of fuel pumps that developed intermittent problems, sometimes months before they finally failed all together. I'd also take a look at the fuel tank vent, just to make sure it's not partially obstructed. And don't overlook some of the unusual suspects like the kickstand safety switch and even the kill switch. Sometimes a weak connection there can mimic running out of fuel.

The Classic Question
Q I have a 2007 Kawasaki 1500 Vulcan Classic. I was wondering if there was a better exhaust system for it with a little louder deeper sound without having to redo the air intake or make the fuel injection richer or would I have to redo everything? Thanks for any help.
Via email

A Better is a nebulous term, and unfortunately there is no short answer to your question There are so many aftermarket exhausts out there that choosing any one as "better" is impossible. My suggestion is to check with your local Kawasaki shop and find out what he recommends and what the majority of his 1500 Classic owners are buying. You might also hit some of the chat rooms to see what's popular and of course the local motorcycle hangouts, where you might hopefully be able to find a bike similar to yours with an aftermarket pipe that you like.

To answer the second part of your question if you're not looking for a performance increase you can install most of the aftermarket pipes without modifying the air box and in many cases you won't have to remap your EFI. However as each pipe and bike is different you should consult with the pipe's manufacturer for will be required.