Running in,- should I worry?

[Ib-Denmark]

This might be difficould to explain, but I dont get much sleep these days.

I had a rebore of my G12 1965 with 8,5 pistons.

After 900 miles I can still experience this:
When hot (like after 5 miles at a speed of 50mph) the bike might loose power and there is a sound like klicking or rattling (it is not stuck ) and I then grib the clutch and thereafter I can start the engine again by releasing the clutch, still while the bike is running and has not stopped.
This happens maybe every 100 km.
The first ore second time I saw this I dismantled the bike , but I saw no damage in the pistons or the barrels.

Should I worry? Ib-Denmark

[SPRIDDLER]

Could it be pre-ignition (pinking) when hot? Is it more noticeable when pulling hard, say uphill in a high gear?
Perhaps fit colder sparkling plugs?

I can't comment on the fact that you can restart the engine by dropping the clutch when running along as I've no experience of twin engines or 8.5 pistons but I've done it with my touring singles.

[ray.woolford]

What fuel are you running on my CSR that has high comp pistons fitted will only run on 99 Octane petrol. I forgot once and filled up with 95 and suffered similar symptoms?

[Triumph-Legend]

Check the spark plugs. It sounds like pinking to me. If the plug colour is very light brown you are likely running to hot. Try a cooler plug and richer fuel mixture to get the motor to run cooler. Do not keep running it hot as the next thing to happen may well be a holed piston. If at all possible use the highes octane fuel available.

I found that I needed to go up quite a few sizes on main jet to optimise performance on my G80 to compensate for modern fuels. Apparently this is very common.

[Rob Harknett]

My G12 engine was rebuilt new big end & other bits. New piston rings were also fitted, it did not really need. The engine wanted to nip up when it got hot. The old rings were put back in.
I have run in many new cars Ib. One of which the engine seemed to want to nip up when it got hot, right up to the time the engine should have been run in. I complained something was wrong. I was told I had a tight engine, so I should continue to run it in until it no longer wanted to try and nip up. It will then prove to be a good engine. I had done 500 running in miles. I did over 2,000 miles before that engine was run in. It proved to be a fast good engine. I had to use top grade fuel or it pinked. The mechanic I complained to ran the engine up until it was hot and kept switching the engine off, each time the engine was switched off it stopped dead. So if when you pull in your clutch lever the engine stops dead Ib, you must have a very tight engine that needs a lot more running in.

[Ib-Denmark]

This might be difficould to explain, but I dont get much sleep these days.

I had a rebore of my G12 1965 with 8,5 pistons.

After 900 miles I can still experience this:
When hot (like after 5 miles at a speed of 50mph) the bike might loose power and there is a sound like klicking or rattling (it is not stuck ) and I then grib the clutch and thereafter I can start the engine again by releasing the clutch, still while the bike is running and has not stopped.
This happens maybe every 100 km.
The first ore second time I saw this I dismantled the bike , but I saw no damage in the pistons or the barrels.

Should I worry? Ib-Denmark

Additional

I use 100 oktane petrol
The ignition is timed to 35 degrees before top.
The plugs (NGK B6ES) are soothy.

[Ib-Denmark]

This might be difficould to explain, but I dont get much sleep these days.

I had a rebore of my G12 1965 with 8,5 pistons.

After 900 miles I can still experience this:
When hot (like after 5 miles at a speed of 50mph) the bike might loose power and there is a sound like klicking or rattling (it is not stuck ) and I then grib the clutch and thereafter I can start the engine again by releasing the clutch, still while the bike is running and has not stopped.
This happens maybe every 100 km.
The first ore second time I saw this I dismantled the bike , but I saw no damage in the pistons or the barrels.

Should I worry? Ib-Denmark

Additional

I use 100 oktane petrol
The ignition is timed to 35 degrees before top.
The plugs (NGK B6ES) are soothy.

I use the same carb.set up as before rebore. (At that time it was 7.5 pistone)

[Ib-Denmark]

This might be difficould to explain, but I dont get much sleep these days.

I had a rebore of my G12 1965 with 8,5 pistons.

After 900 miles I can still experience this:
When hot (like after 5 miles at a speed of 50mph) the bike might loose power and there is a sound like klicking or rattling (it is not stuck ) and I then grib the clutch and thereafter I can start the engine again by releasing the clutch, still while the bike is running and has not stopped.
This happens maybe every 100 km.
The first ore second time I saw this I dismantled the bike , but I saw no damage in the pistons or the barrels.

Should I worry? Ib-Denmark

Additional

I use 100 oktane petrol
The ignition is timed to 35 degrees before top.
The plugs (NGK B6ES) are soothy.

I use the same carb.set up as before rebore. (At that time it was 7.5 pistone)

The ignition is PAZON (as it was before)

[Groily]

It does sound like pinking to me too.
I run mine - 8.5s like you, JPs in my case - on B8ES or B7ES, nothing hotter/softer, with the needle on the second richest slot, and timing at 34° full advance 'for modern fuels' (if it really makes any odds!). That's with a magneto, so less accurate probably than with the Pazon system on yours.
Main jet and other carb settings etc are per CSR, insofar as there are any differences from the standard lower compression set-up (no air filter fitted, newish 389 Monobloc - it was a dog on a concentric I tried, which I could never get quite right).
When running-in I thought she got a bit hot and bothered sometimes on long hills but with a good few thousand miles on the motor, it's free and sweet-running and the plugs are good. Very slight imbalance between the 2, but pretty typical and well within bounds I reckon.
Runs from tickover to full bore and is also good at large throttle / modest revs / heavy load with no pinking. I use 98 fuel, but it has run OK on 95 when 98 was not to be had in self-serve one-pump French garages of a Sunday! And always a first kick starter, hot or cold or anywhere in between.

[Ib-Denmark]

This might be difficould to explain, but I dont get much sleep these days.

I had a rebore of my G12 1965 with 8,5 pistons.

After 900 miles I can still experience this:
When hot (like after 5 miles at a speed of 50mph) the bike might loose power and there is a sound like klicking or rattling (it is not stuck ) and I then grib the clutch and thereafter I can start the engine again by releasing the clutch, still while the bike is running and has not stopped.
This happens maybe every 100 km.
The first ore second time I saw this I dismantled the bike , but I saw no damage in the pistons or the barrels.

Should I worry? Ib-Denmark

Thank you everybody for your input.[/color]
I will try testing, one thing at a time, starting with a colder plug and moving up the needle. (I still dont understand why the plug is sooty)
Regards Ib