Minor Plating damage.

[Raveydavey]

had the barrel off to check why I've lost compression to find a stuck ring. Checked the gap on the rings and found massive wear. I actually ran out of gages the gap is that big.

Anyhow checking the barrel I noticed a small section of the plating next to the exhaust port has rubbed off. I suspect I had a minor nip up some months back when my carb came loose, which might have caused t his. I can't be sure, it might have just happened or could have been there for ages.

The piece is about 2mm X 3mm and comes off the exhaust port on one side. Given the wear to the barrel and that damage I would normally just get it rebored and replated. However I'm supposed to be riding this to Germany in 2 weeks

New rings test out ok, inside the tolerances, just, so would be good for a couple of thousand miles. So the question is do you think the small bit of plating damage will scupper my chances of getting to Giezelwind and back?

The alternative is to break out the credit card and buy a new kit, which means I'm running in on the way across Europe.

I'm inclined just to wing it. What do you recon?

[Scooterlam]

Get a magnifying glass and have a close look
If there's no obvious flakeing I'd wing it.
Dress the edges of the rings and gap slightly looser
Sort it when you get back.

[coaster]

As Derek says, have a close look and also you might find as Ron Moss did on my Avanti, that what looked like the plating being missing was in fact ally from the side of the piston which cleaned off with wet & dry. Several years ago I damaged the bore of a Mugello with a gouge about the width of a pencil extending from just below the top of the barrel to just above the exhaust port. I phoned Camlam for advice and was told to smooth it out with some wet & dry. That ran with a new piston for a few more thousand miles until I retired it in favour of a bigger motor.

[terryj]

As Derek says, have a close look and also you might find as Ron Moss did on my Avanti, that what looked like the plating being missing was in fact ally from the side of the piston which cleaned off with wet & dry. Several years ago I damaged the bore of a Mugello with a gouge about the width of a pencil extending from just below the top of the barrel to just above the exhaust port. I phoned Camlam for advice and was told to smooth it out with some wet & dry. That ran with a new piston for a few more thousand miles until I retired it in favour of a bigger motor.

thanks for that have one like that in the shed waiting for me to get round to sending it off for replating so may just get some new rings throw it together as a running spare will tidy up the shed at the same time with all the bits in one place

[Raveydavey]

Thanks for the replies. It's now back together and sounding sweet as! Here's to winging it. See you in Germany.

[Warkton Tornado No.1]

If the defect is well clear of the exhaust port, say by about 2 mm minimum, I wouldn’t worry. Just think how many more ports other two strokes have that the rings must traverse.

On the other hand, if it is actually on the edge of the exhaust port, it may be an excuse for an additional bit of porting! It’s doubtful your current exhaust port is @ the maximum so now might be a good time to research how wide you should go……

[Raveydavey]

?..if it is actually on the edge of the exhaust port, it may be an excuse for an additional bit of porting! It’s doubtful your current exhaust port is @ the maximum so now might be a good time to research how wide you should go……

What a great idea. Why didn't I think of that?
Cheers no 1