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Discussion Starter #1
Is the FP3 really the only way to update the fuel mapping? According to the dealership it is. I have a 2015 750 with the screaming eagle intake and Street machines slip on exhaust. I am on a tight budget with this bike and I have to do things incrementally.
 

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I have an FP3 on my bike. I mainly use it for monitoring the motor temps and gear positioning since my bike is a 2015 year model. I've hit the rev limiter many times on my bike and having a tach helps when its time to shift up.
 

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Unless you have some kind of tuner, and the V&H Fuel Pack 3 is one of the several available, your bike is going to run lean once you install any kind of high flow air intake. That could lead to burned valves, poor performance, and possibly discolored exhaust system due to increased exhaust gas temperatures.

Probably the best path for having done this incrementally would have been:
1) Start with your choice of either the exhaust or the tuner. The FP3 and possibly some of the others allow you to automatically tune the bike and achieve performance improvements with the tuner alone. Others, like the H-D Screamin' Eagle tuner work strictly from uploaded maps and do you no good as the first upgrade.
2) Install whichever part you didn't install in step #1 and tune the bike for those two components.
3) Install the intake last and update the map.

Documented in another thread is the fact that last year or early this year H-D entered into an agreement with the EPA in the United States. At least here, if you put any tuner on your bike other than the H-D Screamin' Eagle tuner it voids your power train warranty. I believe that is only on model year 2017 and later bikes.
 

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Discussion Starter #4
Thank you both for your input. I am aware of the benefits of the fp3. I am trying g to ascertain if there is a different way to accomplish a richer fuel mixture (among other things) then purchasing the Fp3. Is it possible to adjust it manually?
 

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You can adjust it manually, but only through using an FP3, Harley's tuner or similar. The bike ECU controls the fuel/air mix by dint of the map stored in it's memory.
 

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It's not like a carburetor with adjustment screws. You have to change the map in the ECU.
 

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You have to bite the bullet and get the V&H tuner to make it work perfect. Let me tell you it works like a charm. My high flow K&N air filter and a V&H Competition pipe are now tuned to perfection with a noticeable power difference. Also remember HD stands for hundred dollars.
 

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Discussion Starter #8
Thanks for the clarification. I kinda knew already but I was hopeful. I picked the wrong time (financially) to start upgrading!!!
 

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You really need to fix this

You might want to reinstall the original intake until such time as you can afford the tuner. Running lean and thus hot can get expensive fast.

My father had an old Evinrude Norseman snowmobile. These had a pull cord starter. To make it easier, there was a compression release valve on one cylinder that you would open when starting and then close. Those valves always got worn and leaked air into the cylinder. Since that cylinder was running lean and hot these sleds always died horrible deaths with a hold burned through that same piston. So we were told after his sled left me stranded in Chequamegan National Forest.

Similarly my first car was a 1979 Ford Fairmont that was the last car of an elderly couple. Somewhere along the line they had installed a hand choke, which the dealer removed when I bought the car. They didn't seal things well, though, so I burned the valves until eventually the engine lost enough compression that it was hard to start and would frequently die. A proper job of sealing around the carburetor resolved that problem. Oh yea, and replacing all of the valves cost me a pretty penny as well.

If you see an old motorcycle with the chrome pipes turned blue and black as they come out of the cylinders, that is a sign that the engine ran lean. I don't know if it's hot enough to peel paint or burn it off of a blacked out exhaust or not.


If the bike is used, are you sure there isn't a tuner on it that you haven't found, yet?
 

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Just learning here on computer bikes...…...so if you just add a performance slip on muffler(exhaust flow), you dont need mess with mapping, but if you mess with the intake flow......you need it re-adjusted(computer tuned)? Correct?
 

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IF you feel a need to alter the MAP , look at the Power Vision. Much more than a Tuner it has a lot of tools you may wish to have you can leave it on the bike and use those tools. IF you do buy these types tuners get them from Fuel Moto. They double the factory warranty on them. Also FM will provide a custom tune for your ride preinstall for you to use, they also provide outstanding Tec support for any product they sell.
No install a reasonable exhaust will NOT require a tune, full stage 1 good idea to do so.
Not sure why anyone would do it but install a 100% free flowing exhaust yea you will need help to get it right.
 
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