cylinderhead overhaul

[andy_c101]

Yes, oddjob,
I've got a full gasket set, inc the lower gasket & o-rings.
I'm going to take advice on the bore condition ( I think they're ok).
& yes I'm looking into renewing the rings

cheers

[UK Pete]

lightly/ hone cylinders and renew rings, then you know its all done properly
Pete

[andy_c101]

Pete,
I guess I need to find a local honing m/c shop.
- is there a way of 'breaking the glaze, very very lightly with with v/fine emery cloth ? or is that just plane stupid?

Also whilst the barrels are off, anyone got anytips on how to ease-off the base cylinder gasket? mine is well stuck!
- 3-in-1 oil? hot air gun?.....??

AndyC

[UKROBK7]

I bought a Sealey 3-finger hone off ebay for about £10 and adjusted it to give light pressure to break the glaze on my bores.  Be very careful as you can "bell mouth" the bores i.e taper the top and bottom, you can also go too far with removing metal.  Don't let the hone fingers come too far out of the bores, I used a low speed on my variable speed drill and plenty of oil and moved the hone in and out at a steady rate.  Problem was I had to strip the hone and take sharp edges off the mechanism to get it to adjust the pressure correctly (made in China??!!).  I only gave the bores a light hone and was really pleased with the result giving a nice cross hatching to the bores.  I understand a ball hone is better but I found they were expensive for a one off job.

I have used emery cloth in the past on an old british single engine, I wound the emery around a piece of dowel and stuck it in the drill to make a sort of flap wheel.  It worked but I don't know about using it on 4 bores of a precision instrument like our Hondas!

If you use an engine m/c shop make sure of the quality of their work.  I used a local shop (who do competition engines) to do some valve seat cutting and they cut the seats wrong and nearly ruined a new set of valves, I'm glad I never used them to hone the bores - I can't imagine how they would have ended up.

Good luck
Rob

[Bryanj]

You used to be able to get thingd called Flap Wheels which were a steel spindle with emery cloth on and if you got one a tight fit in the bore that would be ideal as a glaze buster.

[andy_c101]

Right...  the kit is slowly coming together.
I've gotten hold of a great camshaft, in virtually perfect condition!

I'm going to carefully try the sealey light honing tool (suggested by RobK7) to de-glaze the bores & fit new rings.
Have already de-coked piston crowns and cyl/head.

I'm going to see a local place for bead blasting rocker/head & barrels whilst it all apart.

Got new Honda Valves & Guides from CMSNL.
On this last point, the guides do need reaming (just as BryanJ said).
I think I'll need to try D.Silver for the guide driver & the reamer.

Next task will (probably) be to lookout for a Neway valve cutter tool (as mentioned by UK Pete)

Only glitch is I have to take to 'troops' on holiday next week for ten days, so that will add a further delay.....
-it could be a slow process, this rebuild!

Andy C

[andy_c101]

Whilst the barrels are off, I am planning on changing camchain,but will need to split it to feed-on the new one, then rivet that.
I thought my push-bike chain rivetter would do, but the camchain pitch is much smaller.
Anyone know the tool number for splitting/rivetting the camchain?

CamChain is: 219T-088

[Bryanj]

That tool is expensive for a one off job, used a grinder to split and two hammers to re-rivet the new soft link (500 twin one if you didn't get one with the chain)

[andy_c101]

Ref my Valves & guide from CMSNLs

CMSNL say they should NOT need reaming ! ??
& now ask me to return the parts?
I suppose I had better do that; but it will add further delays,
 and makes me start to loose confidence.

That's all for now

[andy_c101]

I'd like to get a second opinion on calculating the acceptable limits & fits for the valve guides I/dia?
see attached info.

my calcs for the I/Ds workout at:
Inlet: 5.460/5.500mm
Ex:     5.460/5.495 mm

[Bryanj]

I never bothered to work it out! Just used the Honda reamer and left it at that

[Tomb]

I recently checked GSXR750 valves against the Suzuki factory manual, a mechanic mate was doing the head for a customer and couldn't understand why the valves were worn below bottom size with small amount of miles on the engine.

I measured the valve stem along its entire length, it was under all the way along, even the part that had not been in the guide, the finish was the same all along so it was obvious the guide area had not been bigger and worn down. The valves were all under size from new. Whether this was an engine mod Suzuki'd done later on and not updated the manuals I dunno. Check your stems all along the length before condemning them.

Your PDF manual chart shows 3 thou clearance for inlet and 4 though clearnce for exhaust as "serviceable limits", that is 'kin massive clearance!! known as piss fit in engineering. I'd be surprised if your valve to guide wear was that bad

To me its not the I.D's of the guides that matter most, its the "fit"  3 or 4 thou is a rattling piss fit. A nice fit is smooth gliding up and down of the valve in the guide with some oil on it, with no side play.

Sorry for so much waffle, crap at explaining whats in me 'ead

[andy_c101]

Yeah I tend to agree the actual bore dimensions alone, are somewhat academic, yes its the actual fit that counts.
- I've got a Honda Reamer on order, just waiting....

[andy_c101]

Still waiting on David Silvers supplier for my valve guide driver & reamer.
"ETA is now end of September" !......yawn.

[andy_c101]

Valve Guides now installed!!!

Boy! It has been a long saga.
Summer has been & gone off the road (but I didn't miss much this year!)

After a  long wait for the Driver tool (No 07942-329-0200)  & Extractor tool (No. 07942-329-0100).

I carefully followed the prescribed heat-n-freeze method.
Only to end up cracking the flange of the first valve guide !!
The Driver Tool is like a blind-hole socket, but it only contacts the flange of the guide.
(used Genuine Honda guides)
Plan B:  used the Extractor tool  to INSTALL, as this is a snug fit with the I/D of the guide and buts squarely at the top of the guide.  (I had realised the extractor removed the old guides fine, without damaging the ends, so I thought why not use it for installing?)

So while house was empty, did some baking!

 Heat-Freeze & lube oil. ...Bingo!....went in nicely with just a few taps.

Reamer worked a treat too.
just some valve lapping to do.

AC