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(10-02-2021, 01:26 AM)Lord Popgun_imp Wrote: Making those videos of the pulse train with the O-scope was fun. Good times
For those not reading the War and Peace thread on it, we had a behind the scenes team of the guys Doc mentioned doing various tests, etc with, AFAIR, Doc and Max doing the posting to keep the clutter down.
Hey Doc, I still have all those emails from you and Max on all that. And I haven’t used the diagnostic tool since then.
My almost 75 year old brain forgot about your oscilloscope! That was a great team effort!
(10-02-2021, 04:28 AM)max_imp Wrote: Hi Dave, thanks for your input, i would be a bit careful with greasing the iacv, this could pick up dust over time and mess things up in there, can you elaborate on this?
And the shortcut involved getting the airbox out from memory, just be aware of the sensors on the airbox.
check this post from enzofour;
http://cb1100forum.com/forum/showthread....#pid291066
Powerdubs might have some methods as well, he specializes in airboxes.
http://cb1100forum.com/forum/showthread....#pid164876
Might give you some poiners
Max, I may be to blame for this, as in post number 782 of the epic thread, I commented that I would be tempted to give it a shot of silicone spray lubricant before reassembling.
In the late 90s, the automation company that I retired from designed and built an automated assembly and test system for General Motors EGR position sensor. During the assembly, contacts (multiple-redundant) received a shot of silicone spray, which was good for life.
Same lubrication process used for the concept of a drive-by-wire automotive throttle switch.
It may not matter as much with the IACV, as lubrication would not be applied to a closed system, however, it might prove useful for component run-in and the air supply is filtered.
I used to suspect that there was some binding interfering with the stepper motor travel, but I've latched on strongly to your heat affecting the magnets theory.
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Hi Max. Yes, you have a very good point about applying the grease, this is why I emphasized "Lightly". I applied a very, very light coating of Mobil-1 synthetic grease to my new IACV when I replaced it. So far so good. But I bow to your superior knowledge (seriously) and advise people to do whatever they feel comfortable doing.
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(10-02-2021, 03:03 AM)Dave_imp Wrote: [quote='SportsterDoc' pid='306783' dateline='1633187460']
Dave in San Diego would be the go-to person. His posts are in the VERY long thread.
Hi Gordo. There was a post somewhere on this forum (maybe the same thread) that identified some short-cuts for replacing the IACV that I didn't use. These short-cuts will save you probably a couple of hours (at least judging by the rate that I work). I was following the procedure defined in the official Honda Service Manual. The changes I made to the recommended procedure are: I removed the rear wheel to gain access to the airbox removal instead of disconnecting the rear shocks and dropping the rear wheel down. Also, there is no need to remove the throttle body assembly from the motorcycle to replace the IACV. Remember to "lightly" grease the new IACV before installing it. Please feel free to IM me if I can be of any assistance. Thumbs up to Titus 2:13. Thank you sir! I sure do appreciate it!!
Titus 2:13
2013 HONDA CB1100
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I have my old / defective IACV that I am willing to send to a forum member to perform an inspection on. My only request is that whoever I send it to is fully competent and capable of performing an in-depth analysis, and that the results are published on this forum. I checked the operation of my new IACV side-by-side against the old / defective IACV and they appeared to function identically. The test I performed consisted of watching the movement of the IACV while I turned the ignition switch off and on. I repeated this test several times with the IACV removed from the engine. The test was performed at ambient temperature. If we have a forum member who has the necessary skills and is up to the task, then just PM me your mailing address. I know without a doubt my old IACV is defective because the high / low idle speed issue was resolved immediately, and has never returned.
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There are some members who may help.
Doubt I could anything more than you have already done.
Max (postage to New Zealand?) and Popgun (oscilloscope)come first to mind.
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Dave i would keep it for now, you are one of the few guys that have one on hand and we know where it is and in the faulty state.
Synchronizator has done some useful testing with both and could not find a difference, we had some email exchanges and he made some video's on how the iacv operated which was very helpful, i also asked him if there was enough strength in the movement in the worm shaft and he replied that there was plenty to motivate the piston.
My question to you is; did the faulty iacv operate normally in the startup cycle and were the rpm's of the engine as you would expect?
And can you feel the attraction of the permanent magnets as you rotate the shaft and if so how many " steps " per revolution, could you somehow measure the torque required to go from one step to the next, maybe have a weight on a piece of wire, measure the weight and the distance from the shaft, ie; 35 gram at 6.3 centimeters.
Maybe repeat this test and heat the iacv ( the rotor needs to be heated and may take a long time to get up to temperature ) and see if that measurement changed and by how much, just curious.
Sorry if you already explained this but it has been a while, in other words did the problem occur only whilst riding?
Also be aware that there is a postal transport issue in the us as i understand it, cheers Dave.
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My question to you is; did the faulty iacv operate normally in the startup cycle and were the rpm's of the engine as you would expect?
Hi Max. My engine idle RPM was inconsistent and unpredictable. I never experienced a problem when the bike was first started (completely cold engine). After the engine was fully warmed up the idle would sometimes go as high as 1,800 RPM, and other times it would "try" to idle as low as 500 RPM, and then stall (I could keep it running by twisting the throttle). This problem would come and go completely unpredictably - it did NOT appear every time the bike was ridden. When the problem occurred I tried all of the tricks (turning the ignition off, performing the TPS reset by twisting the throttle), and nothing worked to eliminate the problem. Shutting the engine off and restarting it would "sometimes" cause the idle RPM to momentarily return to "normal", but the problem would immediately return when I would reach the next stoplight (mostly turning the engine off and restarting it would do nothing.) If I had a torque watch (I used to use one at work) I would measure the torque to rotate the IACV, but I don't. I'll just keep my old, defective IACV sitting in a box for now and maybe someone, someday will like to perform some new tests on it.
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By chance is there a link to the instructions and process to the removal and replacement of the iacv? I dont have a repair manual and was curious if one was on line.
Titus 2:13
2013 HONDA CB1100
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I don’t think there is a manual on-line, but maybe there is and someone will post up.
Basically the manual has you disassemble the rear end of the bike, moving forward until you can get to the airbox.
But there is another way. Check out this post with pics: http://cb1100forum.com/forum/showthread....#pid291066
Good luck with it if you have no manual. You need one.
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(10-04-2021, 10:57 AM)Dave_imp Wrote: My question to you is; did the faulty iacv operate normally in the startup cycle and were the rpm's of the engine as you would expect?
Hi Max. My engine idle RPM was inconsistent and unpredictable. I never experienced a problem when the bike was first started (completely cold engine). After the engine was fully warmed up the idle would sometimes go as high as 1,800 RPM, and other times it would "try" to idle as low as 500 RPM, and then stall (I could keep it running by twisting the throttle). This problem would come and go completely unpredictably - it did NOT appear every time the bike was ridden. When the problem occurred I tried all of the tricks (turning the ignition off, performing the TPS reset by twisting the throttle), and nothing worked to eliminate the problem. Shutting the engine off and restarting it would "sometimes" cause the idle RPM to momentarily return to "normal", but the problem would immediately return when I would reach the next stoplight (mostly turning the engine off and restarting it would do nothing.) If I had a torque watch (I used to use one at work) I would measure the torque to rotate the IACV, but I don't. I'll just keep my old, defective IACV sitting in a box for now and maybe someone, someday will like to perform some new tests on it.
This was exactly my experience with my '14 Standard. Naturally, the two times I took it into a dealership for them to see what I was talking about, it worked just fine.
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