Author Topic: APE cylinder studs too short?  (Read 3262 times)

0 Members and 1 Guest are viewing this topic.

Offline brazwell

  • Honey, everytime I ride my bike, god saves a baby turtle.
  • Full Member
  • *
  • Posts: 64
APE cylinder studs too short?
« on: February 24, 2015, 01:28:09 PM »
So if there is a thread clearly addressing this problem I haven't found it, so I apologize in advance if I'm beating a dead horse. Im doing the top end in my 73 cb750. Ive torqued my APE studs to 8lbs. Now with my heads on, I have approximately three threads left between the top of the stud and top of the nut after torquing with washers.  I have emailed APE and verified they are the correct studs by measuring them. They have suggested "drop a 3/16 or 1/4"  steel ball in the hole and screw the stud down onto it and tighten." Any thoughts?
73' CB750
49' Panhead El
Unicycle (w/ flat tire)

Offline johno

  • Expert
  • ****
  • Posts: 1,314
Re: APE cylinder studs too short?
« Reply #1 on: March 04, 2015, 04:24:47 AM »
Re the ape studs, I had the same issue on my main bearing studs, the studs are the correct length but there is a variation in the depth of holes, I got lucky and just had to have very thin washers on 2 of them and big fat washers on the rest.
My head studs were all spot on. ::)

Hard to imagine such a big variation as 4 to 6mm  :o  are you sure your head or barrel is sitting on the two dowels 100% or your chain tensioner has jumped out of the groove or something simple like that ;)
johno
GRASSHOPPER SOHC HONDAS ARE THE MEANING OF LIFE.

Offline Jerry Rxman Griffin aka MuthaF'er

  • This MuthaF'er is getting to be a
  • Really Old Timer ...
  • *******
  • Posts: 14,902
  • Bought her new 4/75
Re: APE cylinder studs too short?
« Reply #2 on: March 04, 2015, 11:48:18 AM »
Just make sure you install the correct end with thread locker and have the correct height! The 8lbs is basically just a guide so you don't do something wrong. THIS is not like torqueing down a nut. You'll do that with the top nut at no more than 22lbs which will obviously pull the bottoms tight. You are really over-thinking and worrying for no real reason as long as the correct ends are installed and you haven't done something incorrectly.

+1 on the dowels. Remember, there are 2 lengths with the same diameter.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline Big Jay

  • Expert
  • ****
  • Posts: 1,252
    • CBRzone
Re: APE cylinder studs too short?
« Reply #3 on: March 12, 2015, 04:56:18 PM »
Starting a run on main studs today. Will increase the length 2mm

Jay

Offline Bill/BentON Racing

  • Really Old Timer ...
  • *******
  • Posts: 6,725
  • Ex Honda Service Manager, Cert. Honda Tech - Racer
    • BentON Racing
Re: APE cylinder studs too short?
« Reply #4 on: March 12, 2015, 05:13:55 PM »
Way to  go  Jay, K, Bill
BentON Racing Website
OEM Parts | Service | Custom Builds
BentON Racing Facebook
Over 35 years of experience working on vintage motorcycles, with a speciality in Honda SOHC/4 with a focus on the CB750 and other models as well from 1966 - 1985.
______________________________________
1993 HRC RS125 | 1984 NS400R | 1974 Honda CB750/836cc (Calendar Girl) | 1972 CB 500/550 Yoshi Kitted 590cc | 1965 Honda CB450 Black Bomber | 1972 Suzuki T350 | 1973 88cc | Z50/Falcons Pit Bike | 1967 CA100| 1974 CB350 (400F motor)...and more.
______________________________________
See our latest build 'Captain Marvel' CLICK HERE

Offline SOHC4 Cafe Racer Fan

  • Speak up, Whipper-Snapper! I'm a
  • Really Old Timer ...
  • *******
  • Posts: 15,731
  • SOHC/4 Member #1235
Re: APE cylinder studs too short?
« Reply #5 on: March 12, 2015, 08:52:46 PM »
Starting a run on main studs today. Will increase the length 2mm

Jay

Hoping you are running some 550 studs, too.  Nobody has them in stock.
1975 CB550K1 "Blue" Stockish Restomod (http://forums.sohc4.net/index.php?topic=135005.0)
1975 CB550F1 frame/CB650 engine hybrid "The Hot Mess" (http://forums.sohc4.net/index.php/topic,150220.0.html)
2008 Triumph Thruxton (http://forums.sohc4.net/index.php/topic,190956.0.html)
2014 MV Agusta Brutale Dragster 800
2015 Yamaha FZ-09 (http://forums.sohc4.net/index.php/topic,186861.0.html)

"There are some things nobody needs in this world, and a bright-red, hunch-back, warp-speed 900cc cafe racer is one of them — but I want one anyway, and on some days I actually believe I need one.... Being shot out of a cannon will always be better than being squeezed out of a tube. That is why God made fast motorcycles, Bubba." Hunter S. Thompson, Song of the Sausage Creature, Cycle World, March 1995.  (http://www.latexnet.org/~csmith/sausage.html and https://magazine.cycleworld.com/article/1995/3/1/song-of-the-sausage-creature)

Sold/Emeritus
1973 CB750K2 "Bionic Mongrel" (http://forums.sohc4.net/index.php?topic=132734.0) - Sold
1977 CB750K7 "Nine Lives" Restomod (http://forums.sohc4.net/index.php?topic=50490.0) - Sold
2005 RVT1000RR RC51-SP2 "El Diablo" - Sold
2016+ Triumph Thruxton 1200 R (http://forums.sohc4.net/index.php/topic,170198.0.html) - Sold

Offline Big Jay

  • Expert
  • ****
  • Posts: 1,252
    • CBRzone
Re: APE cylinder studs too short?
« Reply #6 on: March 13, 2015, 09:24:02 AM »
Yes making 500/550s too.

Offline SOHC4 Cafe Racer Fan

  • Speak up, Whipper-Snapper! I'm a
  • Really Old Timer ...
  • *******
  • Posts: 15,731
  • SOHC/4 Member #1235
Re: APE cylinder studs too short?
« Reply #7 on: March 13, 2015, 07:51:50 PM »
Yes making 500/550s too.

Excellent!
1975 CB550K1 "Blue" Stockish Restomod (http://forums.sohc4.net/index.php?topic=135005.0)
1975 CB550F1 frame/CB650 engine hybrid "The Hot Mess" (http://forums.sohc4.net/index.php/topic,150220.0.html)
2008 Triumph Thruxton (http://forums.sohc4.net/index.php/topic,190956.0.html)
2014 MV Agusta Brutale Dragster 800
2015 Yamaha FZ-09 (http://forums.sohc4.net/index.php/topic,186861.0.html)

"There are some things nobody needs in this world, and a bright-red, hunch-back, warp-speed 900cc cafe racer is one of them — but I want one anyway, and on some days I actually believe I need one.... Being shot out of a cannon will always be better than being squeezed out of a tube. That is why God made fast motorcycles, Bubba." Hunter S. Thompson, Song of the Sausage Creature, Cycle World, March 1995.  (http://www.latexnet.org/~csmith/sausage.html and https://magazine.cycleworld.com/article/1995/3/1/song-of-the-sausage-creature)

Sold/Emeritus
1973 CB750K2 "Bionic Mongrel" (http://forums.sohc4.net/index.php?topic=132734.0) - Sold
1977 CB750K7 "Nine Lives" Restomod (http://forums.sohc4.net/index.php?topic=50490.0) - Sold
2005 RVT1000RR RC51-SP2 "El Diablo" - Sold
2016+ Triumph Thruxton 1200 R (http://forums.sohc4.net/index.php/topic,170198.0.html) - Sold

Offline PeWe

  • Really Old Timer ...
  • *******
  • Posts: 15,531
  • Bike almost back to the 70's 2015
Re: APE cylinder studs too short?
« Reply #8 on: March 14, 2015, 02:00:50 PM »
Now I understand why some guys use red Loctite threadlocker, tighten all studs to correct upper level not bottom them out. This need a test with head and cylinder + old gasket before final assembly to verfify how deep they should be set. Or just know how long they should be over the case.

I could tighten until the studs bottomed out in my CB750 crank case, but there are others with deeper holes.
« Last Edit: March 14, 2015, 02:04:08 PM by PeWe »
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline BAmann

  • Full Member
  • *
  • Posts: 2
Re: APE cylinder studs too short?
« Reply #9 on: July 09, 2018, 08:50:44 PM »
Warning, Cautionary Tale !!!!!  I am replying to this topic/post because I ran into the same challenge of the HD studs being too short. (See attached photo stock vs HD stud) I liked the suggestion in the post about using a small bearing to provide the proper spacing.  So I tried using a 1/4" chrome bearing and the initial measurements looked great. (So far so good.) However, once I started to torque to 8 lbs, things went horribly wrong. As the torque was coming up to 8 lbs the bottom of the stud hole casing broke off into the engine and the bearing joined the case fragments in the bottom of the engine.  The problem was that even thought the torque was small (less than 8 lbs) using the bearing focused all the force to a small point at the bottom of the hole and broke the case.  The result is that the the cases had to be split and the case fragments and bearing removed and the stud hole welded up.  My recommendation for those of you that come across this issue and this post, "DO NOT USE THE Bearing method to raise the stud height.  If the studs are not factory length or longer return them to the vendor or throw them away and purchase a different brand that are the proper length. ;)

Offline MRieck

  • Really Old Timer ...
  • *******
  • Posts: 10,560
  • Big ideas....
Re: APE cylinder studs too short?
« Reply #10 on: July 11, 2018, 09:18:38 AM »
Set the studs up by height. They do not need to bottom out....... Set them with red Loctite. Special care has to be used when installing the cylinder studs that are oil feeds to the top end.
Owner of the "Million Dollar CB"

Offline Bill/BentON Racing

  • Really Old Timer ...
  • *******
  • Posts: 6,725
  • Ex Honda Service Manager, Cert. Honda Tech - Racer
    • BentON Racing
Re: APE cylinder studs too short?
« Reply #11 on: July 12, 2018, 08:52:10 PM »
+1 especially on oil feed studs, ask me how I know, lol.
BentON Racing Website
OEM Parts | Service | Custom Builds
BentON Racing Facebook
Over 35 years of experience working on vintage motorcycles, with a speciality in Honda SOHC/4 with a focus on the CB750 and other models as well from 1966 - 1985.
______________________________________
1993 HRC RS125 | 1984 NS400R | 1974 Honda CB750/836cc (Calendar Girl) | 1972 CB 500/550 Yoshi Kitted 590cc | 1965 Honda CB450 Black Bomber | 1972 Suzuki T350 | 1973 88cc | Z50/Falcons Pit Bike | 1967 CA100| 1974 CB350 (400F motor)...and more.
______________________________________
See our latest build 'Captain Marvel' CLICK HERE

Offline RP

  • Enthusiast
  • **
  • Posts: 124
    • Restoration Paint
Re: APE cylinder studs too short?
« Reply #12 on: July 13, 2018, 02:06:36 PM »
Had the same issue on APE CBX1000 HD studs.... the ball bearing trick worked at 12 pounds with no issues.  Red Loctite would have been easier.
Ralph
www.paintworkz.com
78 Z1R TC
84 Ninja 900
CBX Pro Stockers
CB750 Funnybike
77 KZ1000 tubo