new dude with a 72 comando combat interstate

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Severely stuck rings can be got by fitting a plate with a grease fitting to the barrel , and pumping away .
On a twin itd pay to link the two chambers , or you could end up lopsided .


Glareing in & seeing if the bores worn , would tell you if the pistons are expendable , in which case
get out the Black & Decker .

CAM SPROCKET . Some types think it evil to turn the nut against the cam chain . a locking device
gets you away unstretched.

Good to see you fixed the existing head . IGNITION & Good valve spring / gear set up are paramount to PERFORMANCE .
As a Combat wasnt really configured for riding to work in the city .
 
Matt Spencer said:
........Severely stuck rings can be got by fitting a plate with a grease fitting to the barrel , and pumping away .
On a twin itd pay to link the two chambers , or you could end up lopsided ........Glareing in & seeing if the bores worn , would tell you if the pistons are expendable , in which case get out the Black & Decker ...... .
That's two good ideas I'd not heard of before, thanks Spencer, another example of why I really like this forum :D
 
hobot said:
I've experienced the lack of low end grunt on my 2 Combats vs 850's which will pull harder starting a pass but too soon run out of pull so Combat has to zoom around it too for some clear road to keep feeling its easger bullding pull so more dangerous than an 850 in that regard. I also know a well ridden 850 in tights can keep a Combat hard on the boil to keep up and only pass after a while in long open. Its rare someone wants a Commando and a Combat at kept in factory kit with life's hard knocks left intact. I saltue that attitude but also know it don't don't take much blemishes for them to look so down trodden long in tooth obsolete clunkers, so best wishes to stop once the outter grime is off. I saw a old brit single dug out of mud of ditch soaked in Strongarm that freed it nicely on display with UGLY before photos so got some myself and very pleased on its claims and other uses you have to follow up yourself. Weakest component is the mechanical adv unit so may not be able to recover the points ignition to idle back unless able and willing to restore AAU with enough parts I've on hand. Other factory quirk is they took .040" off head but not the pushrods so geometry not idea but they run fine up there a long time anyway. Internal oil passage can get clogged then its front location also blamed for hi rpm wet sump that makes a mess but doesn't skip a power beat so easy trick is plug front hole and open new one over the TS case passage. That and a PCV of your choice in breather hose seals mine to over red line thrills so fasteners rust before oil coats. Othter than that pretty much same as other models main guts. May have to rebore/new pistons but rods, crank, TS drive cogs - pump dang robust easy to restore. Cam and lifters may be shot by wear or corrosion. Tag useageicon after a scan of this. strongarmbrand.com/SitePages/Bikers/WinksTriumph/

i understood most of that. :D

in regards to keeping it's imperfections intact, i may not be satisfied with how it looks when i get it back together but its cheap enough to find out.

i got her unstuck. looks decent and useable so far.

new dude with a 72 comando combat interstate
 
Matt Spencer said:
Severely stuck rings can be got by fitting a plate with a grease fitting to the barrel , and pumping away .
On a twin itd pay to link the two chambers , or you could end up lopsided .


Glareing in & seeing if the bores worn , would tell you if the pistons are expendable , in which case
get out the Black & Decker .

CAM SPROCKET . Some types think it evil to turn the nut against the cam chain . a locking device
gets you away unstretched.

Good to see you fixed the existing head . IGNITION & Good valve spring / gear set up are paramount to PERFORMANCE .
As a Combat wasnt really configured for riding to work in the city .

i've heard of using a grease gun to pop seized brake calipers/cylinders but not a motor. good idea.

as you can see, i got it unstuck using the magic juice and some persuasion. i had to whack the top of the pistons with a hammer and a piece of wood. then the kick-starter. they were nice and smooth moving once the crust gave way.
 
Uplifting how well the joy juice and simple rapping worked. Wise as it is to back up the cam cogs with a cut cover or special bracket likely way more have been done w/o this back up and did just fine. You've a good sense of forces vs damage so if cam nut don't give way on decent smooth torque and seems too much strain on the pinon shaft in shallow bore, use plan b. Blocking chain/sprocket also relieves the pull out stress. On most serious fastens I grab a torch first. AMC gear box has a dangerous layshaft bearing common to all Cdos of that era but no worrys pogoing off center stand rides. OMG would that be a world famous lasting video to see a Combat blipping up w/o the bike surrounding it. Do ya know about the common Commando first timing dance lesions?
 
i got the case split. i noticed some discolored areas on the cam. im not sure if its oxidation or what? any ideas?

new dude with a 72 comando combat interstate


next i need to get things mic'd at a machine shop.
 
Looks as light rust patina but not obvious bad wear on that lobe view so should clean up nice but lifter bottom will tell if it was bad before parked. The slight pitting should just hold more oil to surf on as long and nothing proud of the flat surface. I've had to file gouges off cam from a siezure jamning stiff into it but has worked fine 7000+ miles after hand filing and inspected when opening to re seal oil tightness only.
 
monkey wrench said:
i got the case split. i noticed some discolored areas on the cam. im not sure if its oxidation or what? any ideas?

new dude with a 72 comando combat interstate


next i need to get things mic'd at a machine shop.


Light patina, like Hobot said. If you have access to calipers/micrometer, check both intake lobes for equal height, and do the same for the exhausts. As long as a pair are within a couple thou of each other, you should be fine. Trust me; if a cam has a bad lobe, you'll know it when you see it!
As a further sanity check, make sure the followers are flat. If there's any appreaciable pocket worn into any face, the cam lobe will be equally damaged.

Nathan
 
hobot said:
Looks as light rust patina but not obvious bad wear on that lobe view so should clean up nice but lifter bottom will tell if it was bad before parked. The slight pitting should just hold more oil to surf on as long and nothing proud of the flat surface. I've had to file gouges off cam from a siezure jamning stiff into it but has worked fine 7000+ miles after hand filing and inspected when opening to re seal oil tightness only.

thats good to hear. i do have some vernier calipers i'll use to check symetry between lobes.

the followers look very good. no pockets.
 
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