Fuel Injector Service

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Denver_FJR

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I recently had the fuel injectors on my '07 serviced. The bike only has 25k miles and I was a bit skeptical there would be anything there to "clean" but decided to roll the dice.

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I was surprised to see all injectors had some blockage and one had at over 10%. They also replaced the micro filters (which showed only slight debris) and new seals top and bottom. I have used a fair bit of Sea Foam and even a "shock" concentration of Yamaha RingFree. I've always been skeptical of fuel additives and these results only reinforce that belief. And yeah, I only run Top Tier gas.

I used Fuel Injector Man in Florida and had great service but there are folks all over the country offering ultrasonic cleaning. The weather and roads have been crap so haven't done extensive testing but initial results are showing an improvement. If you bike has lost that loving feeling and not getting the throttle response it had back at 1000 miles, this might be something to consider.


 
I am going to be a skeptic on this one for a couple of reasons. I don't know squat about fuel injectors but I recall Jestel stating that they normally had a 4 percent variance. If you look at the "before", take the average (60), the variances (2) are in the 4 percent range but the chart as presented is misleading because the scale used makes the both the differences and improvements appear to be much larger than they really are. Second, the "after" readings are just a little too "perfect".

Of course, the real test is how the injectors perform in the real world and I would think that if they got that "bad" in 25K miles then a lot of riders on this forum would be having some major problems on their high mileage bikes.

 
Very interesting. Can you share what this service cost you? I'm assuming that you pulled the injectors and sent them in, right?
Fred, send me your fuel injectors and for just $160 I'll not only send you a 3D bar graph that shows your injectors used to suck but now are within 0.1%, I'll ADDITIONALLY send you eight hand drawn rings that represent the before and after spray patterns for no extra cost. BUT WAIT, for just $40 more I'll tell you what the lb/hr flow rate is for each injector. BUT WAIT, I'll also throw in a 10 year guarantee that the numbers used in the report are real, genuine numbers and the 3D bars have 3 actual dimensions! This is a limited time offer, once my laboratory is full I'll be unable to accept additional fuel injectors SO HURRY NOW.
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Edit: There are some good shops that do real and valuable fuel injector service which usually includes a balanced flow chart because they aren't all equal. Some do a spray pattern analysis and modification too.

 
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What are the units that are represented in the graph? Do you occasionally give the injectors a workout (high rpm at WOT)?

I'm not 'dissing' your results just wondering about a couple of things.

 
Yeah, yeah... Good healthy cynicism. you guys sound a lot (too much?) like me!
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All I asked was how much it cost.

As for the fancy bar graphs, it is a common ploy used by statisticians of all bents to show the minimum value in a graph not equal zero in order to accentuate the (before to after) differences. And since the values are all whole numbers one would have to assume they are rounding them, which also makes the "after" values seem better than they actually are.

It seems to me that it is possible that the values in the chart are accurate as shown. What would those before differences have meant? A bikes that ran a bit leaner over time and maybe vibrated a bit more than when new? Yeah, that could never be happening...
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Of course, the real test is how the injectors perform in the real world and I would think that if they got that "bad" in 25K miles then a lot of riders on this forum would be having some major problems on their high mileage bikes.
Oh crap...that must be me again! I guess my 160K+ bike that hasn't had injector service is going to explode yet another way or suddenly stop going 145 any more.

I do know injectors flow can be reduced because of a variety of factors including miles, gasoline quality & age, and other things. And I can well imagine doing an injector cleaning if the bike performance because of injectors becomes an issue. I think it was a bigger issue in the days before Jestal was on top of his game and beneficial mainstream injector additives was much sketchier. ;)

But, I too am a bit skeptical about the claims of this particular vendor and the 25K that supposedly has dropped.

One note on this particular vendor--they claim to test the injectors at various "rpms". First it's "rpm" without the s because it stands for "revolutions per minute" and doesn't need to be made plural twice. That's a common mistake and niggly I know, but doesn't add to my confidence level.

But, more importantly, injectors don't revolve. I think it's a completely misused term. Injectors are open or closed for a period of time called a pulse width. Maybe they meant pulses per second or something....

That all said, I know ultrasonic cleaning of plugged injectors is a great thing to do. I did it back in 89 to a set of non-solenoid injectors on a lean running '77 Rabbit and it was like somebody rotorootered sclerotic arteries to become a perfect fog again.

 
Very interesting. Can you share what this service cost you? I'm assuming that you pulled the injectors and sent them in, right?
I paid $88 for the service and I had to pull them and send them in. Fuel Injector Man was actually one of the cheaper ones out there. If I had to do it again and expect I will in another 25k, I would consider going with a service that graphs performance at lower flow rates as low speed performance is more critical to me that WOT.

I am going to be a skeptic on this one for a couple of reasons. I don't know squat about fuel injectors but I recall Jestel stating that they normally had a 4 percent variance. If you look at the "before", take the average (60), the variances (2) are in the 4 percent range but the chart as presented is misleading because the scale used makes the both the differences and improvements appear to be much larger than they really are. Second, the "after" readings are just a little too "perfect".
Of course, the real test is how the injectors perform in the real world and I would think that if they got that "bad" in 25K miles then a lot of riders on this forum would be having some major problems on their high mileage bikes.
I think I'm as big a cynic as anyone and simply offer this info as a data point. I've shown the results to others and have kidded that everyone may get the same before and after graph.
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I am also suspicious the "after" results seem too perfect.

What are the units that are represented in the graph? Do you occasionally give the injectors a workout (high rpm at WOT)?
I'm not 'dissing' your results just wondering about a couple of things.
I've wondered about the graph units as well and don't know.

I've been fighting a poor idle and low RPM throttle response for some time and have tried multiple TBS attempts, general tune-ups and Sea Foam elixirs, including many WOT runs to blow out the carbon. I believe my problem is more significant than the typical "07 throttle response" problem so frequently talked about here.

 
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I had my injectors cleaned and serviced locally, and had the opportunity to watch the entire procedure. In my case, one of the injectors was clearly not injecting properly, due to a clog somewhere.

This was discovered early in the season last year, upon bringing the bike out of storage. It had been parked under the dubious shelter of one of those portable fabric sheds, and although I had used fuel conditioner, I had ordinary methanol 'enhanced' fuel in the tank.

The tech cleaned and flowed all the injectors, but only the malfunctioning one showed any difference after cleaning.

I removed the injectors, and the total cost was $60, iirc.

The mechanic at the local Yamaha dealership claimed it was unusual for an injected bike to have injector problems, as long as clean fuel and regular injector treatments were provided. I do think ring-free is good stuff, and that it is important to store the bike with 'real', methanol-free fuel, plus fuel conditioner

 
I took my truck in years ago for 'injector cleaning'. Funny thing however was that the machine they used had a long arm that grabbed my wallet and drained it completely before it said the injector cleaning job was completed!! Strange how that happened!!!

 
But with new injectors you get new springs and if you really 'splurge' and get new piston return springs that 'injin' will run like an antelope!

 
Good grief - I can't believe the prices!!!

Fred - Go buy a little jewelry ultrasonic cleaner for roughly $30 and get the Pine Sol from beneath he bathroom sink.

PM me for my address to mail me a $29 check and I just saved you a buck.

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