OFFICIAL SITE - Quick Throttle® Magazine - Northwest Edition: Ask Arlin

Q: I have a question about my Sportster. It’s a 2005 and runs great. The only problem I have with it is the strong gas smell it leaves in my garage. Since the garage is under the living room in our house, this makes for very unpleasant odors coming up from the basement. You can smell it at stop lights, too, but it doesn’t smoke. I added new pipes for better sound, and at the dealer’s suggestion I had them install a Screamin’ Eagle air cleaner. Do I need a Power Commander for the fuel injection? The dealer said since the mufflers were Screamin’ Eagle, I wouldn’t need to change my EFI map. Can you give me some advice? I really don’t want to spend the extra money for a Dyno tune, if I don’t need it. — Jamie Cox, Portland, OR

A: Jamie, I hate to give you the news that you do need to spend more money for an updated map. But, this is money well spent, and you’ll appreciate it after a few miles. I can’t say without seeing what your air cleaner looks like, but usually with the better air cleaner, all shrouding is removed, so the filter is more exposed to the air. This also allows more fumes to get out. If possible, shut your bike off outside, and wait a minute before pushing it inside. This should stop most of the problem.

You could have a leaky fuel injector. This would allow raw fuel to seep out while the bike is sitting still, causing lots of fumes. You can check this one yourself, if you can remove the air cleaner. If not, head for the dealer and tell them you want them to look at your fuel injectors while you’re there. It’s a quick thing that should be done in about 15 minutes.

If you can get the cover off yourself, here’s the drill: look in the fuel injection bore and watch what happens when you open the throttle. Hold the throttle open, with the key off. Wait about 5 seconds then close the throttle. Repeat this 3 or 4 times. Then open the throttle, and with a flashlight look down the bore for raw fuel. There shouldn’t be any, as long as the key is off. If there is, you may have an injector that isn’t sealing properly. Get it replaced right away.

Fumes are very dangerous, especially when they’re in your home. Don’t wait, take care of this now. All in all, you shouldn’t’ have any gas fumes coming from your bike.

Q: Arlin, I don’t understand how after spending $20,000+ for a brand new bike you’re then expected to shell out another $1,000+ to get it to run halfway decent. My 2007 Street Glide has a closed loop EFI, and its function is to read the air/fuel ratio and adjust the fuel injection accordingly. If this is so, why would I need to change it if I make an intake exhaust change? Won’t the sensors make the proper adjustments? Please explain. — Jim & Lee, Internet

A: Well, let me see if I can give you a good explanation. Your 2007 comes with oxygen sensors that read the air/fuel mixture in your motor at idle and light loads. These sensors don’t control the EFI out of this range—your map does the job. So, when you let more air in, and more exhaust out, you’re riding on the map in your computer. The oxygen sensors are set to adjust to 14.7 at idle and light loads—not full throttle.

A Power Commander allows you to change the map for the kind of exhaust and intake you have. The map is set not to use the oxygen sensors at all. Without the Power Commander, or a controller like it, you won’t be able to create a map with a new richer fuel/air ratio. The bottom line is you must have a map designed to control all throttle and load possibilities.

Note: Only allow a qualified tech to build this map. It’s one of the most important controls on your bike. Be sure to get a full read-out of your map and air ratio chart. I have customers come in all the time with terrible maps, complaining about how bad their bike is running after just having it tuned. The only way to really tell if your bike is in a good state of tune is to see the air/fuel ratio chart. It should be clear and easy to read. If they don’t provide one with the Dyno tune, head on down the road and find one that does.

Q: Arlin, I read your article every month. Good job! I hope you can help me. Here’s my problem: I bought my pride and joy in March. It’s a 2007 Ultra Classic— the bike I’ve been wanting for ten years. I love the bike, except for a few small problems. These small problems have grown into major irritations over the summer. I hate the transmission clunks, plus my bike isn’t as smooth as my old Road King between 30 and 50 mph. The motor in my bike seems rough and vibrates a lot more, too. My dealer says everything is normal. Have you seen these problems? I did add V&H exhaust, a Screamin’ Eagle air cleaner, and a Race Tuner. The last was suggested by the dealer. I’ve had it in for tuning three times, with no improvement. — Brad Mills, Boise ID

A: Brad, be happy! You’ve got one of the nicest bikes on the market, and your problems can be worked out—one at a time.

Let’s start with your transmission. I’ve had several of the new models in over the past few months, and most of the owners are complaining about shifting clunks. When I ride these bikes and go through the gear box on the Dyno, I only notice the rough engagement from 5th to 6th. And I really don’t have a bottom-line answer of why, at the moment—only from what I read from H-D. It sounds like they changed the cut on the gears, to insure a stronger engagement, possibly to cope with the additional torque from the new motors. We run Red Line gear oil in place of the synthetic HD recommends. Try it. It does seem to make the shifts smoother.

If your motor is jerking at low speed, it’s more than likely your EFI map. The Race Tuner is a good product, but you’ve got to find a tuner that can make it work like it was designed to work. Usually, the jerk is from a lean state of tune at low speeds. Other things can come into play on this one. Anything that can make your motor leaner would cause the problem. Remember, your bike was set up extra lean to help it pass the EPA. Now, open up the air intake with a better air cleaner, and the air out with better exhaust and you’ve succeeded in making your motor leaner than stock. So you have it tuned for the race tuner.

Maybe the exhaust you had installed is leaking. This is a very common problem. All connections need to be sealed to be sure there are no leaks. What are the chances your intake manifold has an air leak? It happens all the time, causing motors to run rough and leaner yet. Your motor is talking to you when it pops and runs rough.

Have these things checked out, you’ll find the problem, if you look hard enough. Other things that may make you think your new 96-inch is rough are parts of your frame touching the motor. I’ve seen lots of exhaust pipes that would touch the frame when the motor moves. This really causes vibration and a rough feel.

Some of the Rinehart Exhausts touch the brake pedal. Take a good look at your bike. If it’s touching anywhere, it will cause your bike to feel rough.

One last thing, look at your rear tire, up off the ground. Seems like about one out of every three or four new bikes I put on the Dyno has an out-of-round tire. This really makes the bike jerk at low speeds, but it smooths out above 50 or so. Be happy—you’ll find the problem, and your bike will purr like a kitten.

Have a question you want answered? E-mail your questions to Arlin Harmon, askarlin@v-twinperformance.net or fullthrottledyno@msn.com or call or stop by the shop in Tacoma, WA, located at 5212-A S. Washington Street, 253-472-7633.


QUICK THROTTLE® MAGAZINE - NORTHWEST EDITION Your Free Local Monthly Motorcycle Magazine!
NATIONAL HOME ABOUT US ARCHIVES BIKER FRIENDLY BIKER GALLERY BIKER NEWS EDITORIAL OUR ADVERTISERS RIDE & EVENTS CALENDAR ADVERTISING INFO H-D's FOR SALE LINK TO US SUBSCRIBE	Q: I have a question about my Sportster. It’s a 2005 and runs great. The only problem I have with it is the strong gas smell it leaves in my garage. Since the garage is under the living room in our house, this makes for very unpleasant odors coming up from the basement. You can smell it at stop lights, too, but it doesn’t smoke. I added new pipes for better sound, and at the dealer’s suggestion I had them install a Screamin’ Eagle air cleaner. Do I need a Power Commander for the fuel injection? The dealer said since the mufflers were Screamin’ Eagle, I wouldn’t need to change my EFI map. Can you give me some advice? I really don’t want to spend the extra money for a Dyno tune, if I don’t need it. — Jamie Cox, Portland, OR A: Jamie, I hate to give you the news that you do need to spend more money for an updated map. But, this is money well spent, and you’ll appreciate it after a few miles. I can’t say without seeing what your air cleaner looks like, but usually with the better air cleaner, all shrouding is removed, so the filter is more exposed to the air. This also allows more fumes to get out. If possible, shut your bike off outside, and wait a minute before pushing it inside. This should stop most of the problem. You could have a leaky fuel injector. This would allow raw fuel to seep out while the bike is sitting still, causing lots of fumes. You can check this one yourself, if you can remove the air cleaner. If not, head for the dealer and tell them you want them to look at your fuel injectors while you’re there. It’s a quick thing that should be done in about 15 minutes. If you can get the cover off yourself, here’s the drill: look in the fuel injection bore and watch what happens when you open the throttle. Hold the throttle open, with the key off. Wait about 5 seconds then close the throttle. Repeat this 3 or 4 times. Then open the throttle, and with a flashlight look down the bore for raw fuel. There shouldn’t be any, as long as the key is off. If there is, you may have an injector that isn’t sealing properly. Get it replaced right away. Fumes are very dangerous, especially when they’re in your home. Don’t wait, take care of this now. All in all, you shouldn’t’ have any gas fumes coming from your bike. Q: Arlin, I don’t understand how after spending $20,000+ for a brand new bike you’re then expected to shell out another $1,000+ to get it to run halfway decent. My 2007 Street Glide has a closed loop EFI, and its function is to read the air/fuel ratio and adjust the fuel injection accordingly. If this is so, why would I need to change it if I make an intake exhaust change? Won’t the sensors make the proper adjustments? Please explain. — Jim & Lee, Internet A: Well, let me see if I can give you a good explanation. Your 2007 comes with oxygen sensors that read the air/fuel mixture in your motor at idle and light loads. These sensors don’t control the EFI out of this range—your map does the job. So, when you let more air in, and more exhaust out, you’re riding on the map in your computer. The oxygen sensors are set to adjust to 14.7 at idle and light loads—not full throttle. A Power Commander allows you to change the map for the kind of exhaust and intake you have. The map is set not to use the oxygen sensors at all. Without the Power Commander, or a controller like it, you won’t be able to create a map with a new richer fuel/air ratio. The bottom line is you must have a map designed to control all throttle and load possibilities. Note: Only allow a qualified tech to build this map. It’s one of the most important controls on your bike. Be sure to get a full read-out of your map and air ratio chart. I have customers come in all the time with terrible maps, complaining about how bad their bike is running after just having it tuned. The only way to really tell if your bike is in a good state of tune is to see the air/fuel ratio chart. It should be clear and easy to read. If they don’t provide one with the Dyno tune, head on down the road and find one that does. Q: Arlin, I read your article every month. Good job! I hope you can help me. Here’s my problem: I bought my pride and joy in March. It’s a 2007 Ultra Classic— the bike I’ve been wanting for ten years. I love the bike, except for a few small problems. These small problems have grown into major irritations over the summer. I hate the transmission clunks, plus my bike isn’t as smooth as my old Road King between 30 and 50 mph. The motor in my bike seems rough and vibrates a lot more, too. My dealer says everything is normal. Have you seen these problems? I did add V&H exhaust, a Screamin’ Eagle air cleaner, and a Race Tuner. The last was suggested by the dealer. I’ve had it in for tuning three times, with no improvement. — Brad Mills, Boise ID A: Brad, be happy! You’ve got one of the nicest bikes on the market, and your problems can be worked out—one at a time. Let’s start with your transmission. I’ve had several of the new models in over the past few months, and most of the owners are complaining about shifting clunks. When I ride these bikes and go through the gear box on the Dyno, I only notice the rough engagement from 5th to 6th. And I really don’t have a bottom-line answer of why, at the moment—only from what I read from H-D. It sounds like they changed the cut on the gears, to insure a stronger engagement, possibly to cope with the additional torque from the new motors. We run Red Line gear oil in place of the synthetic HD recommends. Try it. It does seem to make the shifts smoother. If your motor is jerking at low speed, it’s more than likely your EFI map. The Race Tuner is a good product, but you’ve got to find a tuner that can make it work like it was designed to work. Usually, the jerk is from a lean state of tune at low speeds. Other things can come into play on this one. Anything that can make your motor leaner would cause the problem. Remember, your bike was set up extra lean to help it pass the EPA. Now, open up the air intake with a better air cleaner, and the air out with better exhaust and you’ve succeeded in making your motor leaner than stock. So you have it tuned for the race tuner. Maybe the exhaust you had installed is leaking. This is a very common problem. All connections need to be sealed to be sure there are no leaks. What are the chances your intake manifold has an air leak? It happens all the time, causing motors to run rough and leaner yet. Your motor is talking to you when it pops and runs rough. Have these things checked out, you’ll find the problem, if you look hard enough. Other things that may make you think your new 96-inch is rough are parts of your frame touching the motor. I’ve seen lots of exhaust pipes that would touch the frame when the motor moves. This really causes vibration and a rough feel. Some of the Rinehart Exhausts touch the brake pedal. Take a good look at your bike. If it’s touching anywhere, it will cause your bike to feel rough. One last thing, look at your rear tire, up off the ground. Seems like about one out of every three or four new bikes I put on the Dyno has an out-of-round tire. This really makes the bike jerk at low speeds, but it smooths out above 50 or so. Be happy—you’ll find the problem, and your bike will purr like a kitten. Have a question you want answered? E-mail your questions to Arlin Harmon, askarlin@v-twinperformance.net or fullthrottledyno@msn.com or call or stop by the shop in Tacoma, WA, located at 5212-A S. Washington Street, 253-472-7633.
© 2004-2007 Quick Throttle® Magazine. All rights reserved. This site may not be reproduced in whole or in part without express written permission. Site Design & Maintenance by Reef Media, Ketchikan, Alaska. If you experience problems with this site, please email the webmaster.