M8 new case halves, cam, lifters and head

Started by roadglider08, August 05, 2018, 09:55:49 AM

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PoorUB

I wonder if the sproket wobbles a bit on the crank and keeps flexing the bolt. We all know of the "quality" fit of that crank sprocket.
I am an adult?? When did that happen, and how do I make it stop?!

Heatwave3

Quote from: rigidthumper on August 16, 2018, 07:19:25 AM
Sales Warranty Record- any genuine HD accessory, installed within 60 days of bike purchase, should be listed on this form, as it provides custom coverage ( two years, unlimited mileage, just like the rest of the bike has when new)

Also worth noting that ANY HD parts included on the SWR will also be fully covered for the duration of any ESP, if there is one. So you're looking at as much as 7 years full warranty coverage on ANY HD component you have installed on the bike by a dealer during the first 60 days. If you had a Stage IV kit installed for example anytime AFTER 60 days, you'll have warranty coverage for 1 yr. If you have that same Stage IV kit installed WITHIN 60 days after the bike's purchase, and then add a 7yr ESP, that Stage IV kit will be fully covered for 7yrs instead of 1yr.

rbabos

Quote from: PoorUB on August 17, 2018, 03:28:34 PM
I wonder if the sproket wobbles a bit on the crank and keeps flexing the bolt. We all know of the "quality" fit of that crank sprocket.
My thoughts too. Sloppy anti rotational spline fits between gear and cam also that could be torsionally loading it. Something is working the bolt for it to fail, otherwise it should just sit there, like forever and not break. I doubt torque value is the issue. The B motor cb sprockets were about that and they never fail.
Ron

Rockout Rocker Products

Quote from: rbabos on August 17, 2018, 05:02:17 PM
Quote from: PoorUB on August 17, 2018, 03:28:34 PM
I wonder if the sproket wobbles a bit on the crank and keeps flexing the bolt. We all know of the "quality" fit of that crank sprocket.
My thoughts too. Sloppy anti rotational spline fits between gear and cam also that could be torsionally loading it. Something is working the bolt for it to fail, otherwise it should just sit there, like forever and not break. I doubt torque value is the issue. The B motor cb sprockets were about that and they never fail.
Ron
Quote from: PoorUB on August 17, 2018, 03:28:34 PM
I wonder if the sproket wobbles a bit on the crank and keeps flexing the bolt. We all know of the "quality" fit of that crank sprocket.

I have heard this before... maybe on here. Something about the bolt head not sitting square against the surface, making it flex back & forth at high speed.
www.rockout.biz Stop the top end TAPPING!!

happyman

Some of the early m8 bikes  may have a balance issue when assembled. Should  have been Mark's to identify  where to put them together. The crank and balancer. No makes. Toss them together and roll the dice  out of balance  it from what I understand has too much flex. Vibration  and  presto.  Snap a cam bolt.  Or two till it got figured our.

FXDBI

Has any one checked the depth of the hole and bolt length? Possibly bottoming out and snapping off where the threads end in the hole because it wasn't finished deep enough and it doesn't have room for expansion?   Bob

HD/Wrench

I did check that not even close to bottoming out

happyman

Quote from: FXDBI on August 18, 2018, 03:23:51 PM
Has any one checked the depth of the hole and bolt length? Possibly bottoming out and snapping off where the threads end in the hole because it wasn't finished deep enough and it doesn't have room for expansion?   Bob
Was checked  for sure

FXDBI

Quote from: GMR-PERFORMANCE on August 18, 2018, 03:53:04 PM
I did check that not even close to bottoming out

Thanks Steve I figured has much but I had to ask anyhow. Smart move upgrading, sad fact that its necessary.  Bob

Helmwurst

Any chance these are imported bolts? Just asking? We have a quality inspection department that inspects all fasteners to be sure they are not imported.

HD/Wrench

No idea who makes it or where they get it my first guess is Mexico .

hd06

 It might be a good idea to magnaflux all bolts before instillation. Could be a crack was in the bolt.

rbabos

Quote from: hd06 on February 03, 2019, 04:34:16 AM
It might be a good idea to magnaflux all bolts before instillation. Could be a crack was in the bolt.
Slim to nil you would find any cracks. I'm inclined to blame the components the bolt is used for. For then to crack in use, they are being loaded either in tension or torsional cylces after torquing. Better bolt grade can help but don't think it's the root cause.
Ron

Don D

Would it be crazy to use an ARP stud, AN washer, and nut?

VDeuce

They are slathering those bolts with white thread locker that is really tough stuff. Lot of torque to remove some of these bolts. Same with rocker cover bolts.

Having said that, the bolts really don't impress either. They could be improved on, but IMO the issue is upon disassembly.


Ridetothehill

February 08, 2019, 03:37:25 AM #41 Last Edit: February 09, 2019, 12:12:12 PM by FSG
Quote from: GMR-PERFORMANCE on August 16, 2018, 08:09:13 AM
Just got another  M8 in for tune and found another broken cam bolt .  ( customer thought the lifters need to pump up and that the cam would be loud , IE woods cam   )  First one a shop ( not me) did the install. This one was a cam that customer did his own install .  :nix:
This last one was a mess but no case damage , pump plate lifters cam all junk . he only ran it for a short time , then onto trailer for tune to me


So to say that they have no issues ? Its not rumor what so ever they have issue's that is a fact . From the sumping , to plastic lifter holders that break , to cracked heads from the rocker arm bolt . and the cam bolt breakage is not new  either ,


and here are the pics to prove it   but as a shop I guess I am making this up ??  :hyst:














Where is this cam bolt you are referring to? I am in the process of a cam change and the anti-rotation device bolts have broken off way too easily.

les

February 08, 2019, 08:36:40 AM #42 Last Edit: February 09, 2019, 12:02:56 PM by FSG
We used these during a recent M8 117" hop up.

linky


Ridetothehill

February 08, 2019, 03:28:17 PM #43 Last Edit: February 09, 2019, 12:13:44 PM by FSG
Quote from: happyman on August 16, 2018, 11:48:48 AM
Quote from: GMR-PERFORMANCE on August 16, 2018, 08:09:13 AM
Just got another  M8 in for tune and found another broken cam bolt .  ( customer thought the lifters need to pump up and that the cam would be loud , IE woods cam   )  First one a shop ( not me) did the install. This one was a cam that customer did his own install .  :nix:
This last one was a mess but no case damage , pump plate lifters cam all junk . he only ran it for a short time , then onto trailer for tune to me


So to say that they have no issues ? Its not rumor what so ever they have issue's that is a fact . From the sumping , to plastic lifter holders that break , to cracked heads from the rocker arm bolt . and the cam bolt breakage is not new  either ,


and here are the pics to prove it   but as a shop I guess I am making this up ??  :hyst:














seen this cam bolt puke twice on a personal bike. more to do with another issue that made them snap.  if that motor feels like it has a bit more vibration than most  it has crank and balancer problems just maybe, if its an early production  bagger specially  twin cooled 

Are you referring to the cam sprocket bolt? If so, it sounds crazy that the broke. The HD part # is 25566-06 it's called camshaft drive retention kit $5.49. I think I will be going with a new one.

BVHOG

February 09, 2019, 10:16:51 AM #44 Last Edit: February 09, 2019, 12:01:36 PM by FSG
Quote from: les on February 08, 2019, 08:36:40 AM
We used these during a recent M8 117" hop up.

linky

I use the Fueling ARP on every cam swap, did two this week and the interesting thing is one set of bolts used 3/8 6 pt socket and the next set was 12 point. Both same part number from Feuling.
If you don't have a sense of humor you probably have no sense at all.

codyshop

For what it's worth, the last three M8 cam jobs I've done had the sprockets out of plane by .012" on average.   The SM calls for a max of .009"

PoorUB

I have seen them way out on a TC. So far off I could not get them in spec, only close! Funny how the MoCo doesn't even follow their own spec's!
I am an adult?? When did that happen, and how do I make it stop?!

barny7655

February 11, 2019, 05:17:33 PM #47 Last Edit: February 11, 2019, 06:28:34 PM by barny7655
In my opinion, this bolt is to hard,and will break for this application 
Radial Lines 6   
                                                                                                                         psi                            psi                          psi
grade 8                                                                                                            proof hard           min yield strength          min tensile strength
Medium carbon alloy steel, quenched and tempered   1/4" thru 1-1/2"           120,000                 130,000                     150,000
12.9   
Class 12.9    Metric class                                                                                       MPA                             MPA                       MPA
Alloy steel, quenched and tempered                          1.6mm - 100mm                     970                                 1100                     1220
these are the difference between the two classes ,metric and imperial

3 Radial Lines   
Grade 5                                                                                                              psi                                   psi                          psi
Medium carbon steel, quenched and tempered         1/4" thru 1"                   85,000                           92,000                120,00
   
im thinking this may be more suitable in my opinion  grade 5
riding since 62, BSA bantum the first bike

barny7655

You will notice that the threaded part sheared exactly at the stress point, hence the rolled thread on the inner part,the head of the bolt to me seems to large on the shoulder,not letting a true TQ for the 35 ft/lb  due to surface area , over tq ,i would of used a different bolt smaller shoulder, plus a washer to expand the TQ on the cam gear , just my opinion , cheers Barny
riding since 62, BSA bantum the first bike