Popup Katana piston rings?

[Spuds1234]

I need to order a set of piston rings for the Katana, but Im stumped on what size they are (I forgot to ask my mechanic). I have the factory service manual in front of me, but most of it is above my head.

Can someone please tell me what size rings I need, or what the information would look like in the manual. If necessary I can post pictures of the page in the manual Im looking at.

Cheers

[Taz]

You need to remove the pistons and measure them to guage which oversize you need, also you could then measure the piston to bore clearance to ensure you don't need to rebore and replace the pistons as well. Your bike might still be running the std pistons or may be on the max oversize. You need to ensure you get the right rings for the piston size. You can't just get the biggest ones and hope.

[Katman]

Please tell me 'your mechanic' has sufficient knowledge to figure out what rings are needed. :blink:

[neels]

Are you talking about grades of rings (I think that's what they call it) where there are different rings depending on the machining tolerance of the bores? It might help to post the page of the manual you are talking about to answer your question.

The only way you can really check what size rings you need is to measure the bore, right at the top where it doesn't get worn by the rings, to see if it's still standard. If there isn't too much of a lip at the top and theres no scoring of the bores you might get away with a hone and new rings, otherwise it's a rebore and new pistons as well.

I had to do this when I repistoned my XL, it was already out to .25mm and scored so it's now +1mm.

[Spuds1234]

You need to remove the pistons and measure them to guage which oversize you need, also you could then measure the piston to bore clearance to ensure you don't need to rebore and replace the pistons as well. Your bike might still be running the std pistons or may be on the max oversize. You need to ensure you get the right rings for the piston size. You can't just get the biggest ones and hope.

The engine is in bits currently, I'll ask my mechanic more questions. I just assumed he wouldve told me if I needed oversized rings but I will make sure before I order anything.



Please tell me 'your mechanic' has sufficient knowledge to figure out what rings are needed. :blink:

Yip, Im sure he does, I trust him. Also Im not doing it myself, I lack the knowledge, confidence, and tools to get deep inside the engine. Everything else I'll do though.


Are you talking about grades of rings (I think that's what they call it) where there are different rings depending on the machining tolerance of the bores? It might help to post the page of the manual you are talking about to answer your question.

The only way you can really check what size rings you need is to measure the bore, right at the top where it doesn't get worn by the rings, to see if it's still standard. If there isn't too much of a lip at the top and theres no scoring of the bores you might get away with a hone and new rings, otherwise it's a rebore and new pistons as well.

The bores are fine, they still have the original hone marks on them apparently so he thinks all I need are new rings.

I'll get back to my mechanic before doing anything else.

Thanks for the help guys, you answered my questions well.

Cheers


I had to do this when I repistoned my XL, it was already out to .25mm and scored so it's now +1mm.

[Katman]

Yip, Im sure he does, I trust him.

Then he is the person to ask what rings you should order.

Without measuring your bore no-one here would have a clue.

[Spuds1234]

Without measuring your bore no-one here would have a clue.

You learn something new everyday. I assumed that it would be a standard sized part. Its all good though as Im not in any hurry to get the bike sorted. Its just a project at the moment. Its going to be mint once its back in original condition though.

[F5 Dave]

Yes they are a std size. From the factory. If your 23 yr old bike has close to zero ks then it is unlikely to be worn & std size will be suitable. - Other than that possibility, what were you thinking?

[Spuds1234]

Yes they are a std size. From the factory. If your 23 yr old bike has close to zero ks then it is unlikely to be worn & std size will be suitable. - Other than that possibility, what were you thinking?

The odometer says its close to zero, but then again it has been around the clock.

The engine is getting a complete overhaul and then the shiny bits are being polished and the black bits are being painted. The frame and all the plastics are going to get a lick of paint. There is an original 4 into 2 to go on the bike after thats painted aswell and I also have a centre stand to go on to.

I'd like to put original mirrors on but they seem to be like hens teeth and pretty hard to get so I'll stick with some "fairing" mirrors that I got from Budget Motorcycle Spares that look the part until you get up close.

The plan is to restore it to all its former glory and then ride it on sunny days.