VALVE keeper failure - FIXED!

[bowyer2002]

Whilst riding along, (20-25 mph & under slow acceleration) I felt/heard a bang in my Tiger.
Then it sounded like a lot of rattling before I got it shut off & coasted to the shoulder.
I restarted (restarted easily) it to ride another 100 yds, cresting a hill and then being able to shut it off and coast (thankfully) to my office garage.
The Tiger started right up but was way under-powered and very rattly (is that a word?)
I had about 50 miles on my recent valve shim job after-which, the engine seemed a lot smoother & quieter.
I got my Tiger home and tore it down to check the valves & inspect for damage - the valve train is NOT the source of the noise.
I can turn over the engine manually too.
Any suggestions before I tear into the engine further?
Thanks!

[ssevy]

You can cross your fingers and hope that you got a bad tank of gas; that might cause a backfire and then rough running. I'd drain tank and fuel bowls and check for water. Assuming they're clean, I would pull all 3 plugs and check that all 3 pistons are moving up and down as I hand turned the engine. Tensioner would also be high on my list of suspects. Sprint manufacturing sells a new spring for it, which I replaced when rebuilding my engine. Assuming everything looked okay on the top, I would drain the oil and let some seep  through a clean paper towel or paint filter to check for metal filings.
Sprag would usually fail as you are cranking; it isn't doing any work once the engine is running.
Hopefully Mustang or some of the lads across the pond that are smarter than me will chime in soon🤓

[bowyer2002]

@ssevy - The fuel was the same for the 10 mile ride prior to this incident & is 91 octane w/o ethanol. I do not suspect the fuel.
Tensioner also seems in tact with no evidence of it degrading.
I will also double check the timing while I have the valve cover off.
#1 & #3 pistons were visible and had movement, #2 (under the frame) will be evaluated this evening.
Oil will be changed out too - hopefully with no debris.
Any idea on what compression should be? I will check that next.
Thanks for your .02!

[Mustang]

Check the cam timing Mark's to make sure you didnt jump a tooth

[bowyer2002]

The #2 cylinder moves while rotating the engine.
I drained the oil last night, there were no evident metal particles to indicate bottom end failure.
I did remeasure the clearance on the inboard intake valve on cylinder #1. There was NO CLEARANCE  , 50 miles ago it was in spec @ .005"! (finger in photo)
Other valves were in spec.
I also checked timing - chain was tight & tensioner was in place too.
Timing mark photo is showing when the cam arrows are aligned. I had noticed this timing difference when I did the valve shims, the bike started right up and I rode it 50 miles before it 'broke'.
While doing the shims I ziptied the timing chain to the camshafts for insurance.
I'm thinking that the suspect valve on CYL #1 is what failed.
In reading the Triumph manual, I think I can remove the head w/o removing the entire engine (please confirm) - this may take a bit for me to do.
I want to be sure I have a shop that can do valve work before going too much further!
Any guesses on what the potential valve work might cost me?
Thanks for all your experienced help!

[Mustang]

If you think you need a head job
You would be well advised to look for another head
They are not really rebuildable
Looks more to me like cam timing is off

[bowyer2002]

@Mustang-
Cam timing may be off too - however, upon removing the carbs and their rubber boots I could see the intake valves.
SEE PHOTO -Yellow arrow shows valve in proper closed position, red arrow shows suspect valve 'open' - and manually movable.
I confirmed this since I could grasp the valve with pliers and move it up & down.
Sure enough, the suspect valve is apparently broken or the spring retainers failed (didn't stay up late enough to remove the cams to delve in further).
I hope a new head isn't necessary as parts so far (shims) seem as rare as hens teeth! ANY leads would be appreciated!
Getting the head removed is tonight's scheduled job.

[bowyer2002]

After removing the cam, I discovered that the "keeper" failed!
I was able to freely rotate the valve and while looking thru the intake port, noticing that the valve isn't perpendicular to the valve stem anymore.
The head will come off tonight after I get a 25T bit to fit the head bolts.
I am hoping that I can replace the valve & keeper (lap the valve) and then reassemble the engine.
Any leads on where to get a replacement intake valve and keeper are appreciated!

[London_Phil]

That's some bad luck my friend.

If a new head is needed, I think that other than cam profile, they are fairly interchangeable with other models of same vintage

[Mustang]

Bike bandit has OEM valves listed for steamers for 40 bucks a pop
If the head is not damaged , that's a big if
Cuz that bent valve was rattling around in there and it doesn't take much to destroy a valve guide in the head
Valve guides are not replaceable on a steamer head

[Mustang]

Bike bandit also lists the head assembly for 2005 bucks .

[threepot]

Hi. There are a few heads for sale on ebay your side of the pond. There is one for $70. New are expensive!! Have you taken head off..valve out??

https://www.worldoftriumph.com/partscatalog/catalog/listing/catalog/triumphmc/modelid/23773/block/100058895-1-2/

[ssevy]

The machinist who did my head said he had another Triumph head that he had done for a dealer which they never picked up.
I just dropped him a message to see if he still has it. If he does, I'll give you his info.

[bowyer2002]

@threepot & @ssevy - thanks a lot for checking into the head availability! Those are potential options WAY under $2K!

I did get the head removed last night, it appears that the valve is slightly bent below the valve guide.
The valve rotated in and slid smoothly out of the guide, indication that it was not bent and the guide is okay for a new valve.
The valve seat looked undamaged too.
There were valve marks on the #1 cylinder but those were superficial.
I am getting a new valve & will lap it in - in anticipation that this will be the total fix - along with a new keepers, cup, head gasket, etc.
Photos of disassembly and discovery:

[bowyer2002]

Here is the bike assembled.   
and on the "it's broke" trailer