Nobody is machining anything in the primary.

The vent kit is still fairly new and some of us are of the opinion that there is more to the root cause of the transfer problem, other than just the primary creating a vacuum.

 

Why is your opinion that there’s more to the migration issue than venting the primary?

 

We have done a primary vent for last 2 years .....no transfer . But to be honest I don’t think the 3 of us had much transfer anyway. First one we actually used a NOS Shovelhead vent because we had primary off for chrome and he wanted it...Lol. But I am sure if transfer goes away and nobody stumps this forum would die...lol

 

With all due respect, neither is this.....at least not if you use the same criteria to define “fix” that the MoCo is being held to.

 

It is sort of a multi-faceted observation.

1) The primary is currently designed to vent thru the main shaft and basically "share" the vent for the trans.
2) After watching a video Stonecold posted in a thread that has since been "nuked", the engine was turned over with only the starter. In this video it clearly shows that the transmission pushes a good bit of fluid thru the main shaft bearing into the domed cavity of the trans side cover. And due to the trans cover design, fluid is "pooled" up into the cavity, high enough for trans fluid to be level, if not above, the push rod/main shaft bore.
3) So, if trans fluid is pooled up to the main shaft bore, and the primary does experience some vacuum, and the slave cylinder actuator, while applying the clutch during shift constantly while riding, transmission fluid migrates thru the main shaft to the primary.
4) By removing the cavity in the trans cover, allowing the trans fluid an easier path to return to the transmission you eliminate the "pooling" effect completely. This also allows the shared primary/transmission original venting design to function as normal and keeps the slave actuator from "pumping" fluid thru the mainshaft, as it is well below the mainshaft bore.
5) To make matters a bit more difficult, some bikes transfer more than others. For example, the fat rod was all the rage and worked for some folks, but even it had some issues. The original fat rod had some poor mfg details, rough machine work on the ends. When Greg Williams got some push back on that issue, he did a re-design. The newer fat rod had much better machining, but it also reduced the OD of the push rod, to which I feel was a mistake. And again, the fat rod didn't reduce my transfer issue, not even a little. I confirmed this with a a UV dye kit.
6) Now, for a good while now there has been a guaranteed 100% fix, that fix was Stonecold's. His fix was to machine the trans cover to use a seal. This required a special mainshaft nut and the actuator housing to have a small hole drilled for venting purposes. This posed a couple of small issues. 1) Folks couldn't use the AIM s/c. 2) Cost. 3) The mechanical ability of folks to do the work to install it and drill the hole in the actuator.
7) While we are seeing a lot of reports here, that the vent kit has been successful cure. I have personally seen a bike with extreme transfer issue that the vent kit alone didn't completely stop the problem. It did GREATLY reduce the problem, but NOT completely.

All that said, and again I am no expert and I didn't do all the leg work on this problem as well as deserve 0% credit for my solution, I am of a firm belief I have fixed the problem on MY bike.

 

I will bet the fat pushrod is going to prove not so much of a help latter in down the line.

 

this saga/story may not be over but at least for folks under warranty the answer is simple..allow the HD fix a chance as there is nothing to lose and potential to gain..others not wanting to spend money on it and/or have mechanical inclination and abilities to pursue their own remediation efforts can play by different rules

 

I totally agree.

My bike will be at the dealer next week for other warranty issues, speaker, clutch safety switch and the slave cylinder recall, and they are aware of my transfer issue. They also "know" I have fixed my own problem and are doing their level best to make sure I get the vent kit installed without hassle. The tech doing the recall is just going to put the parts in my old actuator that is in a box in my tour pack. LOL I am keeping it around in case the AIM has an issue, which has lately been happening to folks.

 

Don't have any theories as to the cause of the problem. I know that after installing Mark's fix I have had zero transfer for 16k miles.

 

I also installed “the fix” from Mark and the fat rod. Together, I have since had zero transfer.