M8 trans oil migration
Ultimate HDF Member
Joined: Jul 2014
Posts: 5,649
Likes: 430
From: MASS_hole
doesn't really matter anyway. OT has to do with the m8
I think they all have the hydrolic clutch. As do the S twinkies as far as I have noticed. Mines a regulR bike. Nuttin special (;
I think they all have the hydrolic clutch. As do the S twinkies as far as I have noticed. Mines a regulR bike. Nuttin special (;
Road Warrior
Joined: Jul 2014
Posts: 1,584
Likes: 520
From: VA
OK. So I just checked my 18 model 114. It was at the bottom mark. I added about 2 oz which to took it to between add and full. The thing I wonder is if the came from the factory at the lower mark or the full mark. My bike only has 400 miles on it. Maybe someone with almost no miles can check and see where the factory fill level is.
Tourer
Joined: Apr 2015
Posts: 336
Likes: 26
From: Colorado
I can only tell you my experience. I bought a 2017 CVO Limited on June 30th knowing that some were having this issue. I know call me crazy, anyhow since I knew about the problem I started checking it right away. From the factory is was exactly at the top of the "x" mark which I guess I thought was full. However with each service the dealer has put just a bit more in so it comes to a little over that mark.
Grand HDF Member
Joined: Jun 2010
Posts: 4,584
Likes: 918
From: coast to coast
Other than that I seriously have no idea.
Ultimate HDF Member
Joined: Jul 2014
Posts: 5,649
Likes: 430
From: MASS_hole
The trans main shaft is hollow and used for two things....
One, the clutch pushrod travels between the clutch cable/hydraulic actuator under the trans side cover to the the clutch in the primary, via this hollow shaft.
Two, the shaft is not sealed. It has a secondary job of allowing the pressure to equalize between the trans and primary, and vent out the trans vent, if necessary.
The only way you can lose 8oz of trans oil and have it show up in the primary, is via this shaft...... that much is agreed on. Now why/how it is doing this is an ongoing discussion...
The scary part of this issue is it is unknown how many bikes are affected. It is NOT an issue on all bikes. The transfer rate appears to be dependent on how hard you run the engine, higher rpms have been shown to increase transfer. If you don't look for it, most people won't know they have it...
For example; you ride easy between service visits. You may only have 2-3oz of transfer. The service tech dumps old fluids, without ever checking levels first... and then fills both to proper levels. Even if they did notice the trans a couple ounces low, it would be no cause for concern and they certainly wouldn't look to see if it's in the trans....
Several dyno tuners have tuned bikes, and seen 10oz transferred during the tuning process. One posted that he tuned an '18 CVO Limited, and it transferred 10oz during the tune... so it seems it hasn't been fixed for the '18 models..
One, the clutch pushrod travels between the clutch cable/hydraulic actuator under the trans side cover to the the clutch in the primary, via this hollow shaft.
Two, the shaft is not sealed. It has a secondary job of allowing the pressure to equalize between the trans and primary, and vent out the trans vent, if necessary.
The only way you can lose 8oz of trans oil and have it show up in the primary, is via this shaft...... that much is agreed on. Now why/how it is doing this is an ongoing discussion...
The scary part of this issue is it is unknown how many bikes are affected. It is NOT an issue on all bikes. The transfer rate appears to be dependent on how hard you run the engine, higher rpms have been shown to increase transfer. If you don't look for it, most people won't know they have it...
For example; you ride easy between service visits. You may only have 2-3oz of transfer. The service tech dumps old fluids, without ever checking levels first... and then fills both to proper levels. Even if they did notice the trans a couple ounces low, it would be no cause for concern and they certainly wouldn't look to see if it's in the trans....
Several dyno tuners have tuned bikes, and seen 10oz transferred during the tuning process. One posted that he tuned an '18 CVO Limited, and it transferred 10oz during the tune... so it seems it hasn't been fixed for the '18 models..
Just no known fix
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Advanced
Joined: Jan 2014
Posts: 61
Likes: 15
From: Kansas City
Harley M8 Transmission Migration is True!!!
Guys, this IS an issue and its affecting my brand new 2018 Ultra-Limited Anniversary bike.
1) Bought new - May 5, 2018.
2) 500 miles - Changed Fluids myself and noticed overfilling of primary. Refilled per manual.
3) 1,477 miles (5/22/18) - Dealer drained & refilled/measured primary and transmission (per technical bulletin)
4) 2,448 miles (6/7/18) - Dealer drained and measured both areas and I lost 1.5oz in 1,000 miles in transmission.
5) 5,028 miles (8/10/18) - After getting home from Sturgis, dipstick was low and dealer measured and said I was 4oz low in transmission.
(2,580 miles on transmission fluid)
6) Dealer called Harley and Harley corporate will send the "oil deflector kit/gasket" for dealer to install next week. Drain both areas and refill/measure.
Keep in mind, the service interval is 20,000 miles for the transmission and 10,000 miles for the primary. At the rate of "loss" i am having, I will be transferring 3oz (on low side) per every 2,500 miles or 24oz per every 20,000 mile transmission service!!! I will never have to drain the transmission, just keep adding to the transmission and only service the primary!!!
I hope that my first post here sheds light on "real world" problems for the M8 motor and if not watched and measured carefully, things will get worse or people will not even know they have a problem!!! No one measures what they drain out and compares to what they put in... but with the M* motor, people better start!!!
I also would like to use Redline Shockproof gear oil in the transmission, but afraid that it will mess up the primary clutch pack... or Harley denies warranty coverage of the primary???
Good luck to all...
Jeff
1) Bought new - May 5, 2018.
2) 500 miles - Changed Fluids myself and noticed overfilling of primary. Refilled per manual.
3) 1,477 miles (5/22/18) - Dealer drained & refilled/measured primary and transmission (per technical bulletin)
4) 2,448 miles (6/7/18) - Dealer drained and measured both areas and I lost 1.5oz in 1,000 miles in transmission.
5) 5,028 miles (8/10/18) - After getting home from Sturgis, dipstick was low and dealer measured and said I was 4oz low in transmission.
(2,580 miles on transmission fluid)
6) Dealer called Harley and Harley corporate will send the "oil deflector kit/gasket" for dealer to install next week. Drain both areas and refill/measure.
Keep in mind, the service interval is 20,000 miles for the transmission and 10,000 miles for the primary. At the rate of "loss" i am having, I will be transferring 3oz (on low side) per every 2,500 miles or 24oz per every 20,000 mile transmission service!!! I will never have to drain the transmission, just keep adding to the transmission and only service the primary!!!
I hope that my first post here sheds light on "real world" problems for the M8 motor and if not watched and measured carefully, things will get worse or people will not even know they have a problem!!! No one measures what they drain out and compares to what they put in... but with the M* motor, people better start!!!
I also would like to use Redline Shockproof gear oil in the transmission, but afraid that it will mess up the primary clutch pack... or Harley denies warranty coverage of the primary???
Good luck to all...
Jeff
