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Discussion Starter #1
I had done the valve adjustment over the last winter and in the spring I was having issues down low at very low throttle. Popping and surging mostly. I thought it was because I did some work installing the power commander 5 and autotune. I figure it was a tuning issue and just needed to get it sorted out. Then I checked the wiring from the sensors to the ecm all checked out. Today I broke down and took everything apart to check the valves. I guess I wasn’t to observant the first time. One of the valves on the front cylinder was tighter then the other. One I couldn’t fit the .004 in and the other I could easily fit the .006 found the same on the rear cylinder. The exhaust valve on the front was a little tight and the one on the rear was fine. Would these discrepancies cause issues like these. This time I took a time with extreme patience and made sure all were set right. I have put a ton of miles on the bike this year but I think the valve differences were my fault.


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Nope idle is set right at 850-900. I have been all through this and haven’t found any reasons for it. Everything in the intake and boots are sealed very well so I don’t think it’s a vacuum issue plus I can’t find any vacuum leaks. If it were a sensor the fi light would throw a code and the the ohm testing of the wires would of showen any issues there. I even changed the throttle body thinking it was the tps. I would of thought if the valves had different clearances it was causing a slight timing issue in the valves at low rpm. I’ll keep digging tho


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OK so I got some carb clean and sprayed the boots that meet up with the heads and the motor instantly started to stall and buck. I’m gonna take it all apart again but I’ve been into those boots several times and made sure they were very sealed so I don’t know what’s going on. I don’t think it would be possible for both head gaskets to be bad and both to be sucking air and no other symptoms of bad head gasket so I’ll get back into the intake boots but I’m baffled


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Discussion Starter #8
I don’t know if it was causing the issue but I took the new intake boots off and they slid right off the intake. I had a spare intake with the original boots still on it and it took some work to get them off so I’m wondering if the new ones are out of spec or something. When I put the old ones on my intake they snapped right on easy and were hard to pull off


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Discussion Starter #10
Yea those were replaced with new as well. Looked like it was possibly sucking air from around the bolts on the flange but no real way to know for sure. Couldn’t believe that the carb clean was getting through some how but every time I sprayed the boots where they met the head the bike would stutter hard and stall.


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Discussion Starter #11
I have to replace the eyelet on the ground strap for the coil. The side that connects to the frame. Not sure I understand why that is there anyways since the coil is grounded to the frame when bolted down


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I have to replace the eyelet on the ground strap for the coil. The side that connects to the frame. Not sure I understand why that is there anyways since the coil is grounded to the frame when bolted down


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My .02,
Is that the previous owner added the extra ground strap as the coil ground was a known factory problem due to the strap bolt not grounding properly on the painted frame. There are write ups on this problem know as the "Ground Fix".
 

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Discussion Starter #13
Looked at a few pictures of the rear coil on the bike and they don’t have that ground strap




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Discussion Starter #14
The original ground has already been cleaned and moved to the proper location. I have completed the ground fix a few times hoping I missed something


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Discussion Starter #15
I have zero clue what’s going on anymore. Made sure everything was clean and seated right. Even coated the intake boots with gas resistant silicone on the outside of the oring so that zero gas would get to it and when I spray it it still bogs. I even let the silicone sit so it set up and would have a nice squish when bolted down. The intake clamps are also tight and not out of round or kinked. I always figure my stuff out and always work on my own stuff but this has me absolutely baffled


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Discussion Starter #16
I don’t know if getting gasket material and cutting good thick gaskets for it would help but that’s really my next option


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Overspray getting into the intake??

The Ign coils themselves do not need to be grounded. The 4 wires on the eyelet need the ground. The Ign coil hold down bolt was convenient....

My rear Ign coil is mounted on a plastic frame cover...

The single high voltage winding goes from one spark plug cap to the other spark plug cap. The cylinder head provides the circuit continuity to the sparkplug shells..
 

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Agreed with Hans here. The coils do not have to be grounded so that strap is doing nothing which means the previous owner may not have known what he was doing to anything. The ECU is grounded through the front coil mounting bolt, this is where the problem occurs. With 3 different types of metal trying to make a contact over a painted frame. After a while galvanic corrosion happened as the various metals ate away at each other
 

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Discussion Starter #19
Overspray getting into the intake??



The Ign coils themselves do not need to be grounded. The 4 wires on the eyelet need the ground. The Ign coil hold down bolt was convenient....



My rear Ign coil is mounted on a plastic frame cover...



The single high voltage winding goes from one spark plug cap to the other spark plug cap. The cylinder head provides the circuit continuity to the sparkplug shells..


No overspray in the intake, I have the air filter housing off and I am using a straw on the can and directly spraying it behind the intake flange. 3 times now and no change.


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Discussion Starter #20
Agreed with Hans here. The coils do not have to be grounded so that strap is doing nothing which means the previous owner may not have known what he was doing to anything. The ECU is grounded through the front coil mounting bolt, this is where the problem occurs. With 3 different types of metal trying to make a contact over a painted frame. After a while galvanic corrosion happened as the various metals ate away at each other


It made zero sense to me as well. I took it off. I always wondered why it was there and it didn’t seem factory


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