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I've been noticing in the last year a decline in power of my XX. A couple things stand out. When I bought it, I could release the clutch on a hill in first and it would idle up on its own. Starts from the light in 2nd were easy as well. The bike almost stalls doing this now. Generally speaking, the pickup on flicking the throttle is reduced as well. Here are the things I'm planning on checking, I'd appreciate it if if you guys could lend some advice on the order.

fuel filter

muffler (clogged??)

timing (though you can usually tell timing by a rough idle)

compression test

injectors

(D) Hookers :)

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I bet 90% of the folks here have never even thought of their fuel filter...regardless of mileage.

Whats a fuel filter! :lol:

D: Hookers

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There are 2 places on my daily commute that I end up doing this. One is into the parking garage at work and the second is the light before I join the highway (long wait). I could slow to about 2-3 mph and just let the bike walk itself up as traffic inched ahead. Around 1500rpm it never struggled before. I should probably stop, though I hate burning clutch in its place.

Hell.....that's a good one. I never tried to idle up a hill...too many consequences.

That's always a possibility.

Any possibility (just asking) that it might just be you....now that you are used to the bike instead of in awe?

A clogged fuel filter should make the bike sporadic in its power though, right?

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Its a '99. It isn't sporadic, just generally decreased. When I give it WOT from around 4-6k rpm it does falter a little, but there isn't a stutter as much as a hesitation that wasn't there when I bought the bike. I'll try checking the fuel filter tonite

Thanks Joe, I appreciate yours and everyone elses help so far.

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By a fuel filter, you mean that sock in the tank? My 97 doesn't have a real fuel filter like my Wing which has a in line one like a car. In cars, when the fuel filter is plugged, it will spudder or miss at high rpm when it is using to most fuel.

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how do you ride? Don't take offense to this just asking to help you out. Do you ride WOT all the time? Slow and with traffic never really winding the bike out? A slight mixture of both but leaning towards one or the other? Be honest.

The reason I ask is maybe there is some carbon build up in the engine. Does the Bird run hotter than it used to? Has your mileage decreased noticebly from the day you bought it? How did the plugs look when you changed them; Black, white, scorched, normal, pieces missing?

I'm not really in depth on this bike just yet but does the Bird have a lot of emmisions crap on it? Like a charcoal filter, or PCV valve. I've seen cars in our shop that look great on the outside (engine wise) but run like crap. Tear them down and you could literally fill a gallon bucket with carbon and suite (sp?).

Just some food for thought. I doubt it even has anything to do with it....

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Riding style - Generally with traffic during the commute, occasionally WOT when I get pissed and stuck behind someone. The bike is usually in the 3-7k rpm range, rarely above.

It could very well be carbon build-up. It seems to run hotter and mileage has dramatically decreased, used to be 30-36, now its 20-25. Plugs looked pretty good though, no scorching or broken.

There isn't any emissions being a Texas bike.

how do you ride? Don't take offense to this just asking to help you out. Do you ride WOT all the time? Slow and with traffic never really winding the bike out? A slight mixture of both but leaning towards one or the other? Be honest.

The reason I ask is maybe there is some carbon build up in the engine. Does the Bird run hotter than it used to? Has your mileage decreased noticebly from the day you bought it? How did the plugs look when you changed them; Black, white, scorched, normal, pieces missing?

I'm not really in depth on this bike just yet but does the Bird have a lot of emmisions crap on it? Like a charcoal filter, or PCV valve. I've seen cars in our shop that look great on the outside (engine wise) but run like crap. Tear them down and you could literally fill a gallon bucket with carbon and suite (sp?).

Just some food for thought. I doubt it even has anything to do with it....

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Did this happen right after the plugs and other service? Have you checked the oil level (too much will rob power, had a dealer do that to me)? The "idle up the hill thing" is too vague to use as a symptom, but the gas mileage tells a lot.

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When I changed the plugs I put iridiums in and a new airfilter. Oil level is within the lines (3.8quarts).

Carlos, its not an immediate thing after the maintenance. It's been getting slowly worse.

I didn't peak down the throttle bodies, kept them covered during the change. Should I and if so what should I look for?

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I'd look at your throttle cable adjustments. Also, Kg's explanation of carbing up if you're doing a lot of city riding is a factor too. You need to get the bike out on the open road every now and again to burn the crap out of it. Not just short bursts, but a hour run down an interstate is a good idea.

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When I changed the plugs I put iridiums in

Then consider going back to the platinums. Several people complained of mileage issues with the Iridium plugs. I have not tried them. I don't know if they are truly interchangeable. If the mileage goes down, it stands to reason that power would go down.

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Well most thing have been covered, usally a gradual loss of power is in either the air or fuel systems.

Consider this - most local auto stores sell a litmus type stick which can be used to tell if there is water in your fuel.

Is it possible that the station you have been buying your fuel is having a water contamination problem?

Water can gradually build up inside a fuel filter, to a point where the engine won't run. Prior to this point the engine can gradually loose power.

Can't hurt - possibly you have some water on the bottom of your fuel tank and you don't even know it.

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Oh yeah, forgot to answer Joes question on where I get my fuel. I always buy it at the same Exxon.

I'll run by Autozone tonite to see if they have a stick to check for water. I appreciate all the help. Thanks everyone.

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I switched to the iridiums, better power, no loss of mpg, 40 generally.

Did you get both ends off the ground and check for free rolling of wheels?

bearings/brakes/chain, etc.

Being FI, and mine not, I can't directly correlate. How are the fuel pumps on these Things? Anyone ever clean injectors?

Water in fuel goes right to the bottom where the fuel pickup is, carbed or FI, so it should be a temporary problem.

I'll keep thinking................

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