Help Pistons & rings - FZR250

I'm rebuilding a 3HX1 engine atm & she needs a hone & new set of rings. I've been buying other parts from the local dealer & I check the part numbers against the Zeal. But this engine worries me as it's an earlier year than the 3LN's & the Zeals. The part numbers for the rings & pistons are the same except for the prefix's.
I've measured 3LN pistons & they seem to be the same
The 3HX rings are 1HX 11610-00-00 & the 3LN's & Zeal are 3LN 11610-00-00
Does anyone know for sure if they are the same ?

 

3HX is just a 2KR with EXUP. They will be the earlier model rings I suspect.

Check the thickness of the oil scraper rings and the spring, early models are thicker than the 3LN's.

I found that out when I ordered 1HX rings and tried to fit them to my 3LN pistons.

The top rings fit fine but the oil rings and spring did not.

Flip the piston upside down and check what numbers are cast on the underside of the crown. My genuine and chinese knockoffs (all 3LN's) had 3LN-00 in the castings

 

The Engine No. is 1HX219120, I'm sure the pistons have 3LN00 cast in them.
Someones worked on it in the past, maybe the pistons have been changed to a later set, pistons are good, no wear, shims had been done & everything has been red siliconed up, **** everywhere ! Two of the valves are slightly bent, sticking in the guides hence the head job, probably due to an over rev, no marks on the pistons, who knows maybe they were changed.
I'll have to do the bottom end now in case there's damage there too. All the Zeal stuff is available & pretty cheap so it'll be good if the rings are the same.

 

That's good news, I was looking at the model ID sheet & thought so if those numbers are engine numbers.
The pistons do have 3LN00 on them. The frame is marked 3LN3 so not the original engine I suppose.

 

Internal

 

Well, looks like i'm good with the Zeal parts, rings at least if they're not too expensive from Yamaha. I don't mind paying a bit more, they're quick & no postage & I'm always in a hurry.
I've got two more engines in the que when this ones done.

 

What price are you being quoted for the rings?

 

I bought a genuine set of 3LN rings a few years ago, the price was about $280 AUD posted from Japan. Went through jp-parts.

 

Sounds about right, $58 US + delivery but I'll have other parts to make worthwhile.

 

https://www.2fiftycc.com/index.php?threads/oem-replacement-rings.9411/#post-101704

 

That looks like about 12 mths ago, do you know if he got them made ready to sell ?
And are they full sets, incl the oil rings & springs ?

 

I know he was taking numbers, likely on more than one site also, send him a message and see how he went with the numbers

http://mngforce.typepad.com/nc450vdev/

Particularly this post - http://mngforce.typepad.com/nc450vdev/2017/08/cosworth-piston-rod-kits.html
He got the rings sorted for his VFR400 engines, so he's got the necessary persistence

 

@Willrcr15 - https://www.ebay.com/itm/201631272886?ViewItem=&item=201631272886

Compare to the prices here - http://www.firstclassmotorcycles.co...a/1998/fzx25-zeal/crankshaft-piston#ficheZone

What's the convenience factor worth?

 

I've got a Zeal engine partially disassembled at the moment and will have a 3LN1 also done soonish - I'll put a piston from each side by side and see if I can discern any differences

 

I bought std rings & other parts from Megazip, 370 US, all from Japan so won't take long & all OEM.
But, I can't find a cam chain, anyone got a tip ?

 

What about these guys
http://www.firstclassmotorcycles.com.au/part/yamaha/1HX1217600#top

Though I'm certain that @Linkin or @risky or @Murdo have sourced them cheaper, IIRC they were genuine DID also