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The old timers had a fix for engines that had glazed their bores, and smoked.
They threw a handful of corundum powder down the carb inlet while it was running !!!!
Then changed the oil.

Hmmm, sounds drastic.
But apparently it worked.

The instruction on a packet of rings I found from the 50s era said to install rings,
and go out on the road and give several bursts of HARD acceleration.
From moderately low speeds.
This from the horses mouth, perhaps ??

Using an oil with a high zddp or phosphorus level will not help if it's not bedding in.
If the engine is smoking after a rebore/rebuild then it's normally rings not seating.
If the rings aren't seating then either the honing was too fine or the rings are crap.
That of course is only relevant if you took the bike for a brisk ride after rebuilding,
and the pistons are of usable quality.
All the zddp in the world won't help a smokey engine.
In fact if you actually ask some oil firms about it they say too much zddp will lead
to corrosion of internal parts. That's why they don't advocate oil additives.
If in doubt on oil with these old crates, shell rotella is a good bet.


This is quite interesting.
https://www.onallcylinders.com/2018...h-off-the-shelf-motor-oil-to-save-money/

Bon Ami was a kinder treatment but only on special occasions....................

A lot of folks hereabouts use diesel oil in their old bangers.
High detergent levels and all sorts of long life additives make it an excellent choice.
And its not got the designer-oil price tags....
NOTE. AS LONG AS THE ENGINE WAS CLEANED (INSIDE !) FIRST.

I have several projects I intend to use this in.
But we haven't quite got there yet ...

I tried the Bon Ami treatment once, on a B25 with new rings. It didn't stop it smoking. It just wore out the rings and tapered the bore.


Usually this meant ten hard accelerations from 30 to 50 MPH in high gear with a rest in between blasts to let things cool down if needed.
This is the reason you don't totally baby a new engine. It needs those short bursts of hard work to seat the rings.

Hi Stuart Kirk; I did the hard on the RPM method and did not worked for me (T140E) just scratched the bores (I removed the head etc to see)
The best method yet for me is to just change the speeds at short intervals but keeping the highest speed not to fast.

So I put SAE 30 in a rebuild but only did about 20km or so due to I do not have brakes (I cannot make them to brake. Is a custom bike)
but I have N Hyde 7 plates clutch and that helps with slip so I question again how do you guys do?

Originally Posted by NickL
Originally Posted by Rohan
The old timers.......They threw a handful of corundum powder down the carb inlet while it was running !!!!
Then changed the oil...........

Bon Ami was a kinder treatment but only on special occasions....................


I tried the Bon Ami treatment once, on a B25 with new rings. It didn't stop it smoking. It just wore out the rings and tapered the bore.


Obviously not a special occasion eh?

Lol

Tony told me about the Bon Ami. We used it on my Triumph because it was smoking. Helped. When we tore it down last summer the rings had obviously not seated. When rebuilding two and four stroke singles I use the "accelerate hard, chop the throttle several times" to seat rings. I don't idle the motor long, just heat cycle a couple of times and check for loose nuts. It has worked for me.

Here's the break in oil I'm using- from NAPA Auto store

Considering your location you probably have fairly cool temps. Not sure I would use 30w in hotter temps.
Believe I would stick to 20w/50.

..still my question remains about that type of oil and clutch slip

You might be best starting a new thread on the triumph board. If the motor didn’t share the primary oil like an A65, then I’d suggest using break-in oil in the primary as the clutch doesn’t need oil to function and any form of lubrication is going to do more in the primary than your final drive chain receives. Break in oil should not cause clutch slip.

If your using break in oil and getting clutch slip then there is an issue with your clutch setup.