Some rocker arm side load.

[1FSTRK]

I would bet there was limited testing on the final rocker mount design, I think if you could get the truth, this final design was a knee jerk reaction to the internet conversations about the rocked noise in the 33 year old design used on the Evo and Twin cam engines. The original drawings, 3D printed M8 engines, and  rumor has it early test engines all had the old Evo design rocker shaft mounting. It seems that when the internet discovered that locking the shafts quieted things down the M8 guys took notice. The change was a version of what has been done on individual rocker shaft autos for years but as with all things that come to Harley from other types of engines the HD version will not work without some additional engineering. As with most HD changes we have a good idea implemented in a first draft design.

[rigidthumper]

Re: the cracks- I believe there may be side loads in play when installing the rocker shaft bolts- lots of stress in that area if you don't bleed the lifters first, and set that cylinder at TDC to reduce the load from the pushrod, or you could just use adjustables, and collapse them before removing/installing the rocker shafts.

[1FSTRK]

Re: the cracks- I believe there may be side loads in play when installing the rocker shaft bolts- lots of stress in that area if you don't bleed the lifters first, and set that cylinder at TDC to reduce the load from the pushrod, or you could just use adjustables, and collapse them before removing/installing the rocker shafts.

I agree, this design will be less forgiving when it comes to following the procedure. Many have gotten away with close enough is good enough on the old design. 

The aftermarket will also have a learning curve as they try to calculate max spring pressures and cam lifts. All of these things while finding the strong and weak points of this mounting design.

[psyshack]

I just dropped my King off at the dealer today. Told them to keep it until they figure out why my M8's heads sound like a worn out Twin Cam. Time to find out if Harley is about motorcycles and customer service or selling a life style.

[rbabos]

Re: the cracks- I believe there may be side loads in play when installing the rocker shaft bolts- lots of stress in that area if you don't bleed the lifters first, and set that cylinder at TDC to reduce the load from the pushrod, or you could just use adjustables, and collapse them before removing/installing the rocker shafts.

I agree, this design will be less forgiving when it comes to following the procedure. Many have gotten away with close enough is good enough on the old design. 

The aftermarket will also have a learning curve as they try to calculate max spring pressures and cam lifts. All of these things while finding the strong and weak points of this mounting design.

Well, a normal well thought out attachment would have real studs rather then some lame bolt  spun into the aluminum thread. This is one of the most lame , cheap ass methods of attaching a rocker shaft I've seen.
Ron

[Hossamania]

Re: the cracks- I believe there may be side loads in play when installing the rocker shaft bolts- lots of stress in that area if you don't bleed the lifters first, and set that cylinder at TDC to reduce the load from the pushrod, or you could just use adjustables, and collapse them before removing/installing the rocker shafts.

I agree, this design will be less forgiving when it comes to following the procedure. Many have gotten away with close enough is good enough on the old design. 

The aftermarket will also have a learning curve as they try to calculate max spring pressures and cam lifts. All of these things while finding the strong and weak points of this mounting design.

Well, a normal well thought out attachment would have real studs rather then some lame bolt  spun into the aluminum thread. This is one of the most lame , cheap ass methods of attaching a rocker shaft I've seen.
Ron

But it worked just fine in testing....

[rbabos]

Re: the cracks- I believe there may be side loads in play when installing the rocker shaft bolts- lots of stress in that area if you don't bleed the lifters first, and set that cylinder at TDC to reduce the load from the pushrod, or you could just use adjustables, and collapse them before removing/installing the rocker shafts.

I agree, this design will be less forgiving when it comes to following the procedure. Many have gotten away with close enough is good enough on the old design. 

The aftermarket will also have a learning curve as they try to calculate max spring pressures and cam lifts. All of these things while finding the strong and weak points of this mounting design.

Well, a normal well thought out attachment would have real studs rather then some lame bolt  spun into the aluminum thread. This is one of the most lame , cheap ass methods of attaching a rocker shaft I've seen.
Ron

But it worked just fine in testing....

You mean like the umpteen versions of compensators all beta tested by product purchasers?
I feel they could have made the shaft attachment better and as it stands, how many times can you  R&R those rocker bolts before the threads pull out? Not sure if it's being too cheap or lack of room or base material for a real for true stud with nut torqued on top of the shaft.
Ron

[sfmichael]

I want a new bike, but this is why I feel it best to wait a couple more years 

[Ohio HD]

I want a new bike, but this is why I feel it best to wait a couple more years 

Yeah, I kinda settled myself down too.     

[SLAATY]

GM's 3100 motors had issues with rocker bolts pulling out. Casting bosses were too shallow for the loads induced. Lotsa heli coils in those things. HD may have made the same mistake.

[sfmichael]

GM's 3100 motors had issues with rocker bolts pulling out. Casting bosses were too shallow for the loads induced. Lotsa heli coils in those things. HD may have made the same mistake.

only when they tried to go from a 10mm rocker bolt to an 8mm....wasn't long before they went back to 10

[PoorUB]

I want a new bike, but this is why I feel it best to wait a couple more years 

Yeah, I kinda settled myself down too.     

Same reasons Gonenorth and I bought 2016's. We were both in the running for new bikes and for me I was thinking in 2017, but then with all the talk on the new engine, then having trouble with my 2010 I went with a 2016. The Twin Cam might not be perfect, but after 18 years in production it is a decent engine. Now they come out with the M8 and a lot of new parts and new problems. I would wait until 2019 before I would jump on an M8.

[sfmichael]

I want a new bike, but this is why I feel it best to wait a couple more years 

Yeah, I kinda settled myself down too.     

Same reasons Gonenorth and I bought 2016's. We were both in the running for new bikes and for me I was thinking in 2017, but then with all the talk on the new engine, then having trouble with my 2010 I went with a 2016. The Twin Cam might not be perfect, but after 18 years in production it is a decent engine. Now they come out with the M8 and a lot of new parts and new problems. I would wait until 2019 before I would jump on an M8.

   

[04efidynasuperglide]

wondering about psyshack's post on 3/18 as I have an M8 purchased in august, no bad noise at this time

[psyshack]

wondering about psyshack's post on 3/18 as I have an M8 purchased in august, no bad noise at this time

Here is whats been going on.

Took the bike in 3/18. Rattling rockers, push rods, not bad, bike still running good and pulling like a bullet train. Very slight ping low load steady state cruse. Bike has always burned real 91 octane gas. Has a set of Eliminator 400's for noise a HD Ventilator for air and a FP3 controlling it. Dealer has no concerns about the FP3, DO NOT WORRY ABOUT IT!

3/23 I talk with the dealer. Low oil pressure confirmed. 25 to 28 psi after multiple test. OK,,, I'm now not crazy with concerns of low oil psi. They test it some more for the MoCo. Oil pressure test rig blows hose apart. WoW,, shock and aww. Dealer gets a new hose, repairs the test rig checks the oil psi again. It's now 35 to 38 psi. Confusion sets in. Bike sounds perfect. Sounds like a proper M8 now and not a worn out twin cam. Recheck with with a new test rig same results. Was there crap in a discharge passage, was the by-pass valve stuck open or did it stick closed. Either way oil psi is great now. Info given to the MoCo.

3/29 I call the dealer this morning. Service manager says oil psi is still good, bike is riding out good. MoCo wants them to inspect the the case area around the lifters. There have been a few examples of cracks in the area of the lifters in the case causing low oil psi. Dealer and MoCo want to know if it's ok by me for them to open up the cam chest. I tell them get after it. Then I get a msg at 4:30 pm today from dealer please call. I give them a call. MoCo wants to pull down the back cylinder and go after it from the top down. MoCo wants to look at the rockers, mount and other things for side load and bad mount. Also want to inspect for piston slap. Then on down into the cam chest.

So at this point they a diving deep into the issue and possibly other issues they have seen on early M8's to date. Service manager and I chatted about going forward. If the lower end and case's are good. I'm good with all new parts and stick it back together and put my new tq cam kit in while your at it. If the low end is fubar even a little new engine time. And break it in on the dyno either way it goes.

I've had many questions concerning the time line on this inspection and repair. And yes,,, they will have had the bike two weeks this coming sat. I'm not in a hurry at all. I knew when I bought the M8 that it was new, I'm a beta tester, it's a Harley and it is American. So at best it would be a half ass effort out the gate. We can't seem to do anything right the first time anymore. I'm perfectly happy to let them work on it when it's the best of time for the dealer. I want clear heads and good work done on my sled. And I want it right when it's done. 

[les]

Thanks for taking the time to give that detailed update.  Lots of good information in it.

[psyshack]

wondering about psyshack's post on 3/18 as I have an M8 purchased in august, no bad noise at this time

Here is whats been going on.

Took the bike in 3/18. Rattling rockers, push rods, not bad, bike still running good and pulling like a bullet train. Very slight ping low load steady state cruse. Bike has always burned real 91 octane gas. Has a set of Eliminator 400's for noise a HD Ventilator for air and a FP3 controlling it. Dealer has no concerns about the FP3, DO NOT WORRY ABOUT IT!

3/23 I talk with the dealer. Low oil pressure confirmed. 25 to 28 psi after multiple test. OK,,, I'm now not crazy with concerns of low oil psi. They test it some more for the MoCo. Oil pressure test rig blows hose apart. WoW,, shock and aww. Dealer gets a new hose, repairs the test rig checks the oil psi again. It's now 35 to 38 psi. Confusion sets in. Bike sounds perfect. Sounds like a proper M8 now and not a worn out twin cam. Recheck with with a new test rig same results. Was there crap in a discharge passage, was the by-pass valve stuck open or did it stick closed. Either way oil psi is great now. Info given to the MoCo.

3/29 I call the dealer this morning. Service manager says oil psi is still good, bike is riding out good. MoCo wants them to inspect the the case area around the lifters. There have been a few examples of cracks in the area of the lifters in the case causing low oil psi. Dealer and MoCo want to know if it's ok by me for them to open up the cam chest. I tell them get after it. Then I get a msg at 4:30 pm today from dealer please call. I give them a call. MoCo wants to pull down the back cylinder and go after it from the top down. MoCo wants to look at the rockers, mount and other things for side load and bad mount. Also want to inspect for piston slap. Then on down into the cam chest.

So at this point they a diving deep into the issue and possibly other issues they have seen on early M8's to date. Service manager and I chatted about going forward. If the lower end and case's are good. I'm good with all new parts and stick it back together and put my new tq cam kit in while your at it. If the low end is fubar even a little new engine time. And break it in on the dyno either way it goes.

I've had many questions concerning the time line on this inspection and repair. And yes,,, they will have had the bike two weeks this coming sat. I'm not in a hurry at all. I knew when I bought the M8 that it was new, I'm a beta tester, it's a Harley and it is American. So at best it would be a half ass effort out the gate. We can't seem to do anything right the first time anymore. I'm perfectly happy to let them work on it when it's the best of time for the dealer. I want clear heads and good work done on my sled. And I want it right when it's done.

Well Well Well, The M8 mill is junk. From what I'm hearing it has every problem almost known to the M8. And to top it off I left my cell phone at home today. So the dealer / nobody could ring me up. lolololol

So I went to work today not even caring if I heard from the dealer or not. Maybe why I forgot the phone. Honestly I forget the cell a lot. Turns out a friend of mine decides to ride over to the dealer from Arkansas, check on the bike and swing down my way and hang out. He road his Super Glide over I built for him when he bought it new and over xmas I put a T124 in for him.

He pulls into my office on his really loud and rank Dyna walks in looks at me ask why I wasn't answering my phone and told me to call the dealer.

So I called the dealer. Side loading the rockers, bad rocker mount. Bad piston slap. Front cylinder bore .006" over spec, rear cylinder bore .007" over spec. Plus the damn oil pressure issue. And many other side issues all on the top end. Bottom end looks good. Can you come in Sat. we would welcome your inspection and input and then we need to talk about it.

Service manager asked if my buddy was there on the Dyna. Told him yes. He then said a bunch of your buddys have stopped by checking on your bike worried you would explode. Told him I heard they had been around, and I'm glad they behaved.

So tomorrow I make the two hour drive to my dealer and inspect my M8 and discuss my options. I was told I could have any bike I wanted as a loaner. Just point at it and it's yours. I thanked him. But told him I didn't need it. I told him you saw the bikes my buddys have been riding. I built all of them when my health was better. You don't have a scooter one on the floor as good as I can build. Poor SM, I told him the guy that stopped buy on the rank Dyna today,,, on 3/19 he put his 1984 Honda Ascot 500 in his van and brought it to me that Sunday. You think his Harley is rank. The little Ascot is twin turbo's, water to air intercoolers. Cam'ed, carb'ed, suspension done and will rip a 9.3 quarter with my 300 lb ass on it. Still has the stock piston, rings, rods and low end in it. Lets just make sure my M8 is right. Don't worry about my motorcycle life. I ride.

Tomorrow will be interesting. Off to see if I can find a cop to mess with on the fire breathing Ascot.

[FSG]

The 17300059   SHAFT ROCKER ARM looks to have been changed to a Rev A,  17300059A   

[rbabos]

The 17300059   SHAFT ROCKER ARM looks to have been changed to a Rev A,  17300059A   

So, what's the scoop on the difference? Can't pull anything up with the part numbers.
Ron

[happyman]

The 17300059   SHAFT ROCKER ARM looks to have been changed to a Rev A,  17300059A   

had a dealer  looking for that  new part  ## nothing comes up.

[FSG]

So, what's the scoop on the difference?

I don't know, yet.

[happyman]

So, what's the scoop on the difference?

I don't know, yet.

just different shafts  so something is a bit different. same caps  used if I have it right

[Ohio HD]

The 17300059   SHAFT ROCKER ARM looks to have been changed to a Rev A,  17300059A   

So, what's the scoop on the difference? Can't pull anything up with the part numbers.
Ron

Dealers don't always have the latest info......