Topic: stevecb650c Build 2014 *Video & Pictures inside*

[RJ CB450]

I am going to play counterpoint and recommend against removing pots unless you are planning new rings and cylinder honing.  Just personal preference to prevent unseating rings.  If they get disturbed, might not seal back up.  Also since worn in, not going to reseat even with a fresh hone.  Many might have done it without any "noticable" problem, But I still recommend nay.  The 650 bottom end is stout.  Mine runs zero consumption and the cylinders werent in best shape.  Best diagnostic tool for bottom end is leakdown not teardown.

[grcamna2]

I think RJ has a point Steve,do the cylinder head first and if you find any issues w/ the valves or guides being worn out of spec especially #3...where the guide(s) are too loose and allowing oil past them then that's a good fix.I would have done a leakdown test before they came apart to test the rings.I can't remember if you said but, how many miles was on it? and how did the cond. of the oil look when you first got it ?
Did you know if the PO('s) did any maintenance ?

[RJ CB450]

For comparison to the answers to grcamna2's question.  I have great ring sealing in my bike.  Just ticking 30k km.  Almost 2000 this year.  When I got it last year.  It had sat for years and the maint condition makes me question how bad it was before then for treatment.  Was some surface rust forming.  No pitting but got it cleaned and running great.

My old honda experience is never had cylinder or ring problems.  Always seemed to be piston scoring.  That is a good check.  Look for bad scoring and measure the bores for spec.  To get significant oil fouling, something has to be way out.

My chevette went down a cylinder and had over 50% leakage from piston, but wasnt oil fouling in single piston.  Rings typically mean blowby so check crankcase vent for oil which would also mean even oiling in all cylinders.

[stevecb650c]

I am going to play counterpoint and recommend against removing pots unless you are planning new rings and cylinder honing.  Just personal preference to prevent unseating rings.  If they get disturbed, might not seal back up.  Also since worn in, not going to reseat even with a fresh hone.  Many might have done it without any "noticable" problem, But I still recommend nay.  The 650 bottom end is stout.  Mine runs zero consumption and the cylinders werent in best shape.  Best diagnostic tool for bottom end is leakdown not teardown.

Didn't remove pots yet, although I lifted it slightly removing the cylinder head.
I was thinking if I shod do new rings while everything is out.

I think RJ has a point Steve,do the cylinder head first and if you find any issues w/ the valves or guides being worn out of spec especially #3...where the guide(s) are too loose and allowing oil past them then that's a good fix.I would have done a leakdown test before they came apart to test the rings.I can't remember if you said but, how many miles was on it? and how did the cond. of the oil look when you first got it ?
Did you know if the PO('s) did any maintenance ?

She has 13k miles and the po said she was sitting in the garage barely drove the bike. Unsure of the maintenance. The carbs look great like they have never been disassembled. Screws nuts bolts all look untouched. Only age worn.

[grcamna2]

Steve,
I like your pics of the cylinders,you should be able to check everything nicely while the head is off...,if the base gasket was disturbed then it'd be good to pull the jugs anyway to install a fresh gasket.Then you could measure the parts;I do know what RJ is saying about the original rings not 're-seating' themselves if you remove the cyls...

I guess it's up to you if you want to buy new rings if that's all it needs,if it was mine I would want everything all clean and fresh before I reassemble, but that's me.

[stevecb650c]

Steve,
I like your pics of the cylinders,you should be able to check everything nicely while the head is off...,if the base gasket was disturbed then it'd be good to pull the jugs anyway to install a fresh gasket.Then you could measure the parts;I do know what RJ is saying about the original rings not 're-seating' themselves if you remove the cyls...

I guess it's up to you if you want to buy new rings if that's all it needs,if it was mine I would want everything all clean and fresh before I reassemble, but that's me.

I'm gonna take more pictures with day light
First I'll have the top end in check first.
I'll keep the jugs in for now, clean the top pistons and see where I'm at, gonna wait for my Athena gasket kit to come in. Does this kit include piston rings or do I have to find these to?

[RJ CB450]

My athena gasket kit for my 82 came only with all soft parts for engine kit.  This is stem seals, orings, and flat gaskets, etc.  Hard parts like bearings, rings, guides, and fasteners are separate.  In case of stuff like rings and bearings, this is because often might need different sized on a rebuild.

[stevecb650c]

My athena gasket kit for my 82 came only with all soft parts for engine kit.  This is stem seals, orings, and flat gaskets, etc.  Hard parts like bearings, rings, guides, and fasteners are separate.  In case of stuff like rings and bearings, this is because often might need different sized on a rebuild.

Ok cool I'll check in with y'all when I get some more work done.
I just want to ride, beautiful weather out here south Florida.

[stevecb650c]

UPDATE

Pistion heads are cleaned.


ok so i took my cylinder head to a local shop to get the valves checked, lapped, and cleaned. they quoted me 245. and to replace the seals 45 dollars.
im on a budget so i decided to do the cleaning and lapping myself just need to get some tools together to get the valves out.
input?

[grcamna2]

Steve,
I think you'll be good w/ pulling the valves & springs out and keeping all of'em organized like you do.I think OEM Honda valve seals will work best;you can check the valve guides w/ the springs removed & if any of the guides are too loose then you'll have to give it to the shop to replace them and regrind those particular valves and seats. Have you asked any members here if they'll do the cylinder head service for you ? or if they recommend anyone who's good and reasonable ?