honing a nicalsealed barrel

[cezeta]

ive got a pinasco barrel thats getting a new piston and rings, the bore is fine but polished from the old piston, should i hone it to carry oil better or not bother?

[Wayne Miller]

ive got a pinasco barrel thats getting a new piston and rings, the bore is fine but polished from the old piston, should i hone it to carry oil better or not bother?

No, If it looks like the nikasil is wearing thin in places get it re done if not then leave it be

[cezeta]

what are the tell tell signs of wearing thin, ive only had them damaged then re plated. is there a colour change or anything

[Wayne Miller]

what are the tell tell signs of wearing thin, ive only had them damaged then re plated. is there a colour change or anything

The easyest way to check is to simply check you cylinder walls for scratches or chips, if you find any of these its time to have it replated. However if you dont find any scratches or chips etc it doesnt mean that its OK you should still check it with a dial bore gauge to check that its perfectly round. If its not then the same as before, its time for a replate. However Ive ran cylinders with small scratches and small chips and theyve been fine. Also when I said No to re honing thats not exactly true you can use a ball hone to de glase them but I would just use scotch brite on the nikasil lining and all should be OK

[cezeta]

ok cool, i usualy run a three leg honer/de glazer on an iron barrel.

[Wayne Miller]

ok cool, i usualy run a three leg honer/de glazer on an iron barrel.

I realy wouldnt use that mate, theres no need. When your honing a Nikasil cylinder you always run the risk of chipping the Nikasil around the port edges and if you do that you'll possibly f@@k it up completely and then you'll need to replate it.
Best bet is spray it with WD40 and scotch brite it, its up to the job and you wont run the risk of chipping the Nikasil

[sean brady scooters]

and use the RED scotch pad ...the grey is just to fine

[Wayne Miller]

Oh b@11@x yeah Seans right use the general purpose pad (Maroon/Red) I forgot to say you can get different types/grades you wouldnt want to use the Heavy Duty ones

They do:

Heavy Duty - Light Brown
Blending - Dark Gray
General Purpose - Maroon
Ultra Fine - Light Gray

I think they do another one too thats less abrasive than ultra fine ?
The Dark gray ones are good to use on ally after youve been dremeling away, They actually make it look like you know what your doing

This is after using a Dark Gray pad, I think I used a maroon one after this but dont have a pic

[cezeta]

ive got all but the light grey so should look like i know what im doing then

whats going on in that picture, is that a conversion plate for another barrel?

[Wayne Miller]

ive got all but the light grey so should look like i know what im doing then

whats going on in that picture, is that a conversion plate for another barrel?

Yes mate, thats exactly what it is, its a conversion plate to fit a rotax cylinder to a smallframe engine that I did last year.



But yeah, back to the barrel use the Red scotchbrite that should do the job