Welcome, Guest
Username: Password: Remember me

TOPIC:

Stripped cam bearing threads - shim under buckets 29 Aug 2018 12:56 #789975

  • daveo
  • daveo's Avatar
  • Offline
  • Premium Member
  • Posts: 2755
  • Thank you received: 622
+1

Just be careful not to monkey up the threads. :whistle:
1982 KZ1100-A2

Please Log in or Create an account to join the conversation.

Stripped cam bearing threads - shim under buckets 30 Oct 2018 11:13 #793097

  • Kray-Z
  • Kray-Z's Avatar Topic Author
  • Offline
  • User
  • I need more power Scotty....
  • Posts: 583
  • Thank you received: 107
Well, after a tooooo long hiatus away from this project we are back at it. The owner went down a different trail, literally! He devoted most of his project time and effort to his new dirt play-bike built from a nicely warmed up 78 XL350 motor and frame mated with CRF250R wheels, brakes, suspension, etc.. Plus we put a few other bikes in some shows back in the late spring, but I digress...

As for the project - All of our machined thread inserts are now Red Loctite glued into the head, the cam caps have been faced to the same height above the head, the cam cover is drilled, the specialty studs have been carefully trial fit, remaining fasteners are ordered, and I'm machining the spacers that will go between the cam cap nuts and the underside of the cover to keep the cover from bowing in or cracking. I've used this method on other shim - under engines before, BTW, and it does work - really well, in fact.

Here is a link to the owner's post on Instagram....


More photos and description to follow....
2-04 R1, 81 CSR1000, 81 LTD1000, 2-83 GPz1100, 3-79CBX, 81 CBX, 3-XS650, 84 Venture, +parts
Quote "speed costs money...how fast do you want to go?" (Which Z movie?)
Universal formula for how many motorcycles one should own = n + 1, where n is how many motorcycles you own right now....

Please Log in or Create an account to join the conversation.

Stripped cam bearing threads - shim under buckets 30 Oct 2018 12:14 #793099

  • kevski
  • kevski's Avatar
  • Offline
  • User
  • Posts: 415
  • Thank you received: 154
I done this in 2004 and the bike is still racking up the miles, had to mill out a little in the cam cover to allow for the nuts, the studs are 8mm stepped down to 6mm with the 6mm parts of the studs in two different lengths to allow the continued use of locating dowels, not sure i am keen on your solution as it appears you have deleted the locating dowels thus allowing the possible movement of the caps when under load and the added potential of 16 extra oil leaks through the cam cover, there are many out there who will not grasp what you are doing, but all said and done this is thinking outside of the box and to be commended, i wish you every success and will keep watchin this threadd.
Attachments:

Please Log in or Create an account to join the conversation.

Last edit: by kevski.

Stripped cam bearing threads - shim under buckets 30 Oct 2018 16:59 #793117

  • Kray-Z
  • Kray-Z's Avatar Topic Author
  • Offline
  • User
  • I need more power Scotty....
  • Posts: 583
  • Thank you received: 107
Kevski,

Still using the 8 mm knock pins / dowels, 2 pins per cap - same as stock on the intake cam, but the exhaust caps were tricky on this head as the previous heli-coil repairs destroyed the index of one 8 mm locating holes on each of the exhaust cam caps. Our solution was to use one of the other holes as the new location for the 2nd knock pin, after carefully checking the bearing alignment. Particularly the end play thrust caps (no.s 1 and 3, if memory serves) need a secure index point, as all bearing caps tend to wander around a bit when engine is running, if not located with more than just bolt clamping force alone.

Plus this "GPz1400" will get 410 cams now, with potential for a set of 465/435's in the future. I'm putting these studs in my twin plug J head also, but not for "repair" as my original 6 mm threads are undamaged / intact. I'm running up to 485 lift and heavy springs, and the cams will be in and out routinely, so the studs should help the threads last and prevent them from ever pulling out and ruining the engine....I hope.
2-04 R1, 81 CSR1000, 81 LTD1000, 2-83 GPz1100, 3-79CBX, 81 CBX, 3-XS650, 84 Venture, +parts
Quote "speed costs money...how fast do you want to go?" (Which Z movie?)
Universal formula for how many motorcycles one should own = n + 1, where n is how many motorcycles you own right now....

Please Log in or Create an account to join the conversation.

Stripped cam bearing threads - shim under buckets 08 Feb 2020 22:03 #818877

  • DoctoRot
  • DoctoRot's Avatar
  • Offline
  • Sustaining Member
  • Oh, the usual... I bowl, I drive around...
  • Posts: 2543
  • Thank you received: 664
Reviving this thread as i have run into a similar issue. This head I have had an old heli-coil repair that failed. I was able to remove that heli-coil and install a time sert deeper.... which failed, the entire hole is now stripped. I cannot install a big-sert as this is one of the holes with a dowel. I like the stud idea, but because of the completely stripped hole I cannot install a 8mm stud, I could go to 9mm but this would remove the 8mm dowel. How bad would it be to run only one locating dowel?

Please Log in or Create an account to join the conversation.

Last edit: by DoctoRot.

Stripped cam bearing threads - shim under buckets 09 Feb 2020 03:06 #818881

  • zed1015
  • zed1015's Avatar
  • Offline
  • User
  • Posts: 2885
  • Thank you received: 1441
The caps are self aligning once bolted down on the cam and the dowels were primarily there for their location during the line boring process at the factory.
Caps 1 and 3 are slightly more crucial to their lateral position as they control cam float to prevent the cam sprocket nuts drifting into the head casting.
Running just the 1 dowel in either of the caps won't affect anything.
AIR CORRECTOR JETS FOR VM CARBS AND ETHANOL RESISTANT VITON CHOKE PLUNGER SEAL REPLACMENT FOR ALL CLASSIC AND MODERN MOTORCYCLE CARBURETTORS
kzrider.com/forum/23-for-sale/611992-air-corrector-jets-





Please Log in or Create an account to join the conversation.

Last edit: by zed1015.

Stripped cam bearing threads - shim under buckets 09 Feb 2020 09:17 #818893

  • DoctoRot
  • DoctoRot's Avatar
  • Offline
  • Sustaining Member
  • Oh, the usual... I bowl, I drive around...
  • Posts: 2543
  • Thank you received: 664
thanks for the info Zed, what would be your choice of repair for my situation?

Please Log in or Create an account to join the conversation.

Stripped cam bearing threads - shim under buckets 09 Feb 2020 09:59 #818896

  • zed1015
  • zed1015's Avatar
  • Offline
  • User
  • Posts: 2885
  • Thank you received: 1441
If you haven't a lathe.
You can drill and tap to M10 max ( decent pillar drill needed )
Then fit a solid steel M10 slug flush with the head. ( use M10 x 1.25 or 1.5mm threaded bar, studs or bolts as slug material )
Bolt on the cap and use the hole as a guide to get the center for drilling and tapping back to 6mm.
Once done you can then drill 8mm to take the dowel.
The success of this obviously relies on your skill, accuracy and mechanical competence etc
If you have a lathe you can make the whole slug and location dowel in one piece as in the attached pic.

I'm just about to do a head that needs all 16 doing.

AIR CORRECTOR JETS FOR VM CARBS AND ETHANOL RESISTANT VITON CHOKE PLUNGER SEAL REPLACMENT FOR ALL CLASSIC AND MODERN MOTORCYCLE CARBURETTORS
kzrider.com/forum/23-for-sale/611992-air-corrector-jets-





Attachments:
The following user(s) said Thank You: DoctoRot

Please Log in or Create an account to join the conversation.

Stripped cam bearing threads - shim under buckets 09 Feb 2020 12:47 #818907

  • daveo
  • daveo's Avatar
  • Offline
  • Premium Member
  • Posts: 2755
  • Thank you received: 622
Pics to aid discussion:

Can a successful Big-Sert repair be made without using the flange tool (shown in picture), to avoid affecting the dowel-bore portion of the hole itself?

:unsure:






:)
1982 KZ1100-A2

Attachments:

Please Log in or Create an account to join the conversation.

Last edit: by daveo.

Stripped cam bearing threads - shim under buckets 09 Feb 2020 15:10 #818914

  • DoctoRot
  • DoctoRot's Avatar
  • Offline
  • Sustaining Member
  • Oh, the usual... I bowl, I drive around...
  • Posts: 2543
  • Thank you received: 664
I do have access to a lathe and mill. I’m a self taught hobbiest and this is something I think I can do but the accuracy of the locating dowels worries me. How accurate do the locating dowels need to be? My only worry is that if I replace the locating dowel and my insert is off a little bit it will throw the cap alignment off and chew up bearings.

Please Log in or Create an account to join the conversation.

Last edit: by DoctoRot.

Stripped cam bearing threads - shim under buckets 09 Feb 2020 15:52 #818916

  • zed1015
  • zed1015's Avatar
  • Offline
  • User
  • Posts: 2885
  • Thank you received: 1441
They need to be accurate if you want to replicate the original set up and using the cap as a drilling guide with cam installed should be as good as anybody can get.
As said previously the dowels were only there to locate the caps during the line boring process and their importance in use is overly exaggerated.
The cap is self aligning on the cam and once bolted down can't move.
How many split shell big end bearings do you see with location dowels ? practically none... and they have to cope with more than a simple stationary rotating shaft.
Just fix the thread with an 10mm slug flush with the head, forget the dowel and use the cap as a guide for drilling and tapping the 6mm thread.
If it's an end float control cap you only need the one dowel to stop it moving sideways anyway.
AIR CORRECTOR JETS FOR VM CARBS AND ETHANOL RESISTANT VITON CHOKE PLUNGER SEAL REPLACMENT FOR ALL CLASSIC AND MODERN MOTORCYCLE CARBURETTORS
kzrider.com/forum/23-for-sale/611992-air-corrector-jets-





The following user(s) said Thank You: DoctoRot, Puffin, SWest, Scirocco

Please Log in or Create an account to join the conversation.

Last edit: by zed1015.

Stripped cam bearing threads - shim under buckets 09 Feb 2020 19:53 #818933

  • DoctoRot
  • DoctoRot's Avatar
  • Offline
  • Sustaining Member
  • Oh, the usual... I bowl, I drive around...
  • Posts: 2543
  • Thank you received: 664
great advice. thank you.

Please Log in or Create an account to join the conversation.

Powered by Kunena Forum