A little bit of knowledge........

[taysidedragon]

My dad told me a funny story from many moons ago about when a little bit of knowledge can be a dangerous thing.

A professor at the university he worked at rode into work one Monday morning on his old Rudge m/c. It was smoking and rattling like mad, sounding like it was on it's last legs. When asked what the problem was, he said he couldn't understand it because he'd just fitted new valves and guides on the weekend.
On further investigation it turned out that he'd fitted the valve guides but the valves were a bit tight so instead of reaming the guides he'd put valve grinding paste on the valve stems and ground them in until they were a sliding fit. He thought he could clean all the grinding paste off, but didn't realise that the phosphor bronze guides would absorb some paste and keep on grinding! By Monday they were already knackered. 😣

[MrDavo]

  He should have had a word with the metallurgy department first!

As a teenager, I broke my hand punching a T100 which had ground to a halt after oiling up its plugs again, and was smoking badly. I took the head off, literally single handed as the other one was now in plaster (after the punch, which did zero damage to the Triumph), to find home made BRASS valve guides, that now had oval shaped holes in them instead of round ones!

No names no legal liability, I'd recently bought it from a Morecambe dealer, trading from a shed on an industrial estate, who's son went on to win 23 TTs.

[taysidedragon]

He should have had a word with the metallurgy department first!

As a teenager, I broke my hand punching a T100 which had ground to a halt after oiling up its plugs again, and was smoking badly. I took the head off, literally single handed as the other one was now in plaster (after the punch, which did zero damage to the Triumph), to find home made BRASS valve guides, that now had oval shaped holes in them instead of round ones!

No names no legal liability, I'd recently bought it from a Morecambe dealer, trading from a shed on an industrial estate, who's son went on to win 23 TTs.

It sounds like he owes you a mcpint! 😉

[Bryanj]

Now some Triumphs had bronze guides from the factory and the manual was very missleading about them, may only have been 650 tho

[Tomb]

Triumphs were well known for oval-ing the guides, it was said to be due to the short rockers and higher lift cams meaning the valve was put under considerable side load when being pushed down by the arc that the tappet screw travelled through. The guides in my 500 were originally Bronze which were worn oval, I made new longer bronze guides to help reduce the wear. It worked well, and is still in service.