Injector Service

[Professor]

I'm making some changes to my bike. After a bit of thought, I decided to send the injectors off to have them flowed, cleaned, and re-flowed.

Units are CC/Min
Before
1) 232 bad spray pattern
2) 241
3) 246
4) 239
Balance 6%
Total Lbs per Hour 91.24

After
1) 249
2) 250
3) 252
4) 250

Balance 1.2%
Total Lbs per Hour 95.33


What this means is tuning with air fuel, with the same map on all cylinders"¦. I was having a couple of cylinders lean and a couple rich to make the number correct.

Not good"¦.. I think I may have found 5 or 6 hp!

Tuning on a dyno might have pointed it out as I could have been getting different results tuning by each cylinder.

Food for thought anyhow.

 

[Mr Bogus]

I know it is going to sound flakey but Slick 50 (and I would never use their oil additives PERIOD) makes a synthetic injector cleaner that really works... We use this on automotive injectors at their suggested strength and it cleans up spray patters.. (it will not help a clogged or plugged unit) but it does wonders sharpening up spray patterns..

I guess you get to even out your injector pulse widths huh?

 

[69ls1]

How many miles were on your injectors? Who did you send them to and what kind of turnaround time?

 

[GIXERHP]

Rick what did you spend on having them flowed, ive got a set s2000 injectors i wanted to upgrade to!

 

[Professor]

How many miles were on your injectors? Who did you send them to and what kind of turnaround time?

Between 9-10K.... I honestly forgot!

RC Engineering. Sent them out 2nd day air on Thursday. Theu got them on Tuesday.... completed on Tuesday... Shipped back 2nd day air, got them on Thursday. So 1 week total including 4 days shipping. Pretty quick.

Link http://www.rceng.com/

 

[Professor]

Rick what did you spend on having them flowed, ive got a set s2000 injectors i wanted to upgrade to!

$24 per injector +shipping.

 

[Professor]

I know it is going to sound flakey but Slick 50 (and I would never use their oil additives PERIOD) makes a synthetic injector cleaner that really works...

I thought about it.... but didn't want to take chances and still have a bit of unknown.

I'm going to be running it on the dyno soon. I was thinking of the $$$ wasted if they were not right. I'm pretty confident in them now.

 

[mikev7]

Wouldnt fuel injector cleaner do the same?

 

[Mr Bogus]

Wouldnt fuel injector cleaner do the same?

not really, it is better at keeping them clean... when they service injectors they are put on a flow bench and checked for output..

they then run them through a chemical and ultrasonic cleaning to remove any gunk inside..

IF it is just some varnish or gum blockage, the cleaner can get it out normally.. Most "on the car" flushes will help but if you have a hard blockage, the injector needs pulled..

Where the problem is that by the time most people pay the labor, deal with the down time (rental car etc) it is easier and faster to just replace the unit.. For Ricks purpose he is way ahead to have a matched set of flowed units vs even a new set of unknown units. You can flow them yourself but you need to build a bench with fuel supply, harness and beakers to measure the flow (we used low volatility solvents, not gas)

 

[69ls1]

Thanks professor. I was thinking about sending mine to MPS. They charge $25 per plus shipping also. I will check out RC engineering.

 

[Big Red]

Are the stock injectors generally off specs from the factory ?

 

[Professor]

likely... I've been told they need to be within 2%. Mine were not modified, only cleaned and they come out within 1.2%. They were not performing correctly clogged or whatever.

If a guy had 3 or 4 sets, it would be best to have them mixed to match sets.

A good dyno tuner can adjust for that 1-2% variance in manufacturing tolerance by individually tuning the cylinders. You don't want to adjust to fix a problem, however.

 

[GoldenChild]

I can do exchange service if you don't want to be down..

 

[69ls1]

PM sent to Goldenchlild.

 

[GoldenChild]

back atcha

 

[javie]

I sent mine off to injector rehab, $16 each free shipping back. They ran a flow+dynamic test. I literally have no clue what the dynamic test results are showing me, lots of numbers heh but here's what my injectors came out

Before After
1)250 252
2)246 250
3)242 250
4)243 250
Variance is at .794% now!

First injector is an over achiever heh anyone wanna take a look at the dynamic test results for me and try and explain what it means? I have a pdf file of it I can email ya