Sleeved barrels, sleeve rotated!

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I am wondering what I should do with them, if anything. Anybody experienced this before on iron barrels?
How risk-friendly are you? The interference-fit appears to be insufficient - my guess is due to operator error or cheating. Your barrel appears to be a cast iron one. Recommended interference is 0.0025" according to L.A. Sleeve. Your engine runs under high thermal loads, and increasing the interference fit to 0.0035" may be advisable. Some air-cooled engines will require an interference of up to 0.0080", presumably when using alloy barrels.
Have the liner carefully removed without increasing the barrel bore. Do a calibration of the barrel bore using a bore thrust plate. Prepare a new slightly oversized lipped liner of good quality.
Install heavily shrunk liner by way of cryogenic cooling and by heating the barrel to 220 'C. Install liner under compression.

-Knut
 
How risk-friendly are you? The interference-fit appears to be insufficient - my guess is due to operator error or cheating. Your barrel appears to be a cast iron one. Recommended interference is 0.0025" according to L.A. Sleeve. Your engine runs under high thermal loads, and increasing the interference fit to 0.0035" may be advisable. Some air-cooled engines will require an interference of up to 0.0080", presumably when using alloy barrels.
Have the liner carefully removed without increasing the barrel bore. Do a calibration of the barrel bore using a bore thrust plate. Prepare a new slightly oversized lipped liner of good quality.
Install heavily shrunk liner by way of cryogenic cooling and by heating the barrel to 220 'C. Install liner under compression.

-Knut
Nice idea, but not in rural France, they don't do that stuff to tractors, they use government subsidies and get a new one!

In truth, it is a rule of diminishing returns. A new set of iron barrels is £600, plus shipping and import to France. And it looks like we will soon have several choices for alloy barrels.

This set of barrels cost me £50 and the liners around £60, plus maybe £150 for fitting and honing to suit pistons. The work was done through Norman White, using I understood RGM liners, by the machine shop he uses and trusts, it wasn't their first attempt at liners. (Norman has responded to me privately, but he has been playing at Donington this weekend. The inevitable request is can I get them to him, well today 'Covid Rules', no.)

I have no sentimental attachment, it was simply an attempt at having a spare set economically. The money was spent years ago.

If I can get them to Norman some time I will let him see what can be done.

I am planning to install a Maney set I bought from Yves ex Big Spender, and if that doesn't work I go back to the set I used in the first place and are sitting on the shelf awaiting next move.
 
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Nice idea, but not in rural France, they don't do that stuff to tractors, they use government subsidies and get a new one!

In truth, it is a rule of diminishing returns. A new set of iron barrels is £600, plus shipping and import to France. And it looks like we will soon have several choices for alloy barrels.

You are right. Buying a new barrel while you can get one is most often a better proposition than repairing/restoring old stuff.

I had L.A. Sleeve put a quality liner into a barrel for my G80CS this spring. It cost me almost 500 USD. Some years ago I did this to a Norton 750 barrel also with it's fragile base casting. Wrong decision, but we learn by our mistakes.

-Knut
 
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Why


You are right. Buying a new barrel while you can get one is most often a better proposition than repairing/restoring old stuff.

I had L.A. Sleeve put a quality liner into a barrel for my G80CS this spring. It cost me almost 500 USD. Some years ago I did this to a Norton 750 barrel also with it's fragile base casting. Wrong decision, but we learn by our mistakes.

-Knut
I don't think I would have done it to an original 750 barrel, for the reason you mention. And back when I did have a 750 the parts were easily enough located. When I needed some parts I picked up a crashed road bike!

And I think it is possible to resurrect this 850 set and pin the sleeves to prevent reoccurrence. But that will be back burner.

And I think I would then be happy enough to use it in a road bike running to 5500/6000 as a typical max, 6500 rarely, 6800 in extremis.

But I don't have a road bike today!
 
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