We found an awesome contact in the automotive industry in China to help get us in touch with the higher quality manufacturers over there. A lot of Ducatisti associate "make a quick buck" with "Made in China". Me? Not so much. My awesome ex Zina is Chinese, and she's first quality. This latest contact suffers my questions well when it comes to quantifying what I'm trying to buy from them. We're about to do injectors...
The iwp043 Pico injector is in many many Monsters. All the injected 2V models before the 696/1100 era. I've been on a buying spree getting injectors (throttle bodies) from eBay for my research.
Here's an example of me testing some injectors:
I spent about a week of R&D figuring out how to use this tester. The o'scope is so I can know definitively what the pulse duration is. I ended up calibrating the graduated cylinders so they all have the same error. I'll probably take the bench apart and install longer tubing so they're all dead on displayed values. This was a fantastic lesson on determining reality and testing procedures.
Oh, right. Injectors.
I've gotten to where I believe I can offer "matched" injectors for our bikes. We should be able to sell a pair of matched injectors for 15% less than buying 2 new injectors from the Weber aftermarket. The iwp043 seems to be the stepchild of the pico family. No one agrees what they should flow. And they have pretty wide variation from the Ducatis I got samples from. I'm researching the iwp043 as well as the iwp069. While the iwp043 can be bought for many $$$, the 069 is not available separately from Ducati at all so replacement means buying from odd sources or getting a new throttle body / shower assembly!
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I took apart a couple of injectors. They're amazingly simple and definitely not rocket science...
This is an OEM injector from a 2002 Monster 750 whose throttle bodies were on eBay. The gray plastic bit in the middle is a coil. When activated, it pulls the piston towards it against the spring which then allows fuel to flow from the left to the right through the injector.
These injectors are not intended to be rebuildable. The outer shell is tac welded to the inner body at the edge under the plastic connector. Additionally, the outer shell is pressed in to retain the plastic coil in it. The filter (far left) is not removable.
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This injector is from China, made by the best factory in my buyer's opinion. I bought 12 samples for testing to go along with the 12 we got from parted out used Ducatis. The Chinese injector fits together more tightly than the Weber part. And not in a sloppy way, either. The filter was in so tight that when I punched the brass tube up through the body, it wasn't able to push the filter out and instead broke through it. The orings on the inside are slightly differently sized, though the quality of fit (and appearance of sealing ability) seemed similar between OEM and aftermarket.
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The business end of the injectors! The shiny face of the cup points down into the injector's outer housing. The inner shiny ring on the cup seals against the polished floor of the injector where the 4 holes are.
In comparing the performance of the injectors, the aftermarket ones had 40 to 60% less deviation between flow values at most pulse durations. At 3 msec pulse (about the most narrow it can ever be), the aftermarket ones have 40% more deviation. In the 12 injector samples I got, I was able to match 3 pairs really well. One set is in my own S2R800 right now. Maybe it runs more smoothly? Got me... these aren't intended to be a "what can I spend money on next" type of purchase, they are for folks chasing serious running issues. Or anal retentive types analyzing per-cylinder A/F ratio and want a good starting point.
The 2002 M750 I got the injectors from probably didn't run well, if at all. One injector appeared to have all 4 holes clogged. Ultrasonic cleaning is something of snake oil, but I did it to these 2 and it got them sort of working, although at 60% flow compared to desired! So this bike ran like ass. Maybe new injectors for a reasonable price could have helped the bike stay alive? We don't know.
Right now, the big sticking point I have with these aftermarket iwp043s is that the factory making them was convinced by the previous buyer to make these flow 15% less gas than the original weber items. It's kinda perplexing. Why? I put the most lean set into my S2R800 and it's actually a lot better than it was before! The pipes were sooted up and idling stank of gasoline. I got ok MPG and the bike ran great, so I didn't mess with it. My bike is all stock with an Arrow full system. And the new injectors. I'm hoping the factory can up the flow more where it "should be".
Yaaay, beer time.
