--- In
anzhonda600owners@yahoogroups.com
, "Bill" wrote:
> There has been some talk lately about the timing chain. Moving it one or
> more teeth forward or back. There is a file on the ANZhonda600owners Yahoo
> group page that walks you through the process. If the cam chain is
> stretched then it has stressed the metal past it's original configuration
> and will fail. There are cam chains that are similar and are in the heavy
> duty range. I use a racing chain that comes several links longer and has to
> be shortened and a split link used to put it back together. The file on
> the group page walks you through this process and if all your cam chain
> wheels and slipper are still in good usable condition you can change out the
> cam chain without taking the engine all apart.
> Bill
> _____
> From:
anzhonda600owners@yahoogroups.com
> [mailto:
anzhonda600owners@yahoogroups.com
] On Behalf Of T W S
> Sent: Friday, January 18, 2013 9:09 AM
> To:
anzhonda600owners@yahoogroups.com
> Subject: Re: [anzhonda600owners] Re: Power tuning a Honda Z600, the next
> frontier....
> im not the smartest guy around so You gotta forgive me on this. It seems to
> me when there is a sprocket and a chain, its made with a certain spacing. If
> you remove a link, it would seem that it would prematurely take out the gear
> tooth edges that make contact with it which would be worse than a stretched
> chain. ive not looked to deep in these engines so i dont know what the gear
> looks like. Just seems like it would do more damage than good? Tim
> --- On Fri, 1/18/13, richmccolman wrote:
> From: richmccolman
> Subject: [anzhonda600owners] Re: Power tuning a Honda Z600, the next
> frontier....
> To:
anzhonda600owners@yahoogroups.com
> Date: Friday, January 18, 2013, 9:37 AM
> Three words, Mark: DON'T DO IT!
> When I owned my N600 back in the late '70s, I had a loose timing chain that
> had jumped a a link or two. (This was the second time the car had jumped
> time in roughly 20,000 miles, due, I figured out later, to me driving the
> car past red-line speed. [Since there's no tach in the sedan, this fact was
> less obvious, especially to a novice driver at the time.] The first time the
> chain had jumped, it jumped so far that it bent valves, so that time I did a
> major engine tear-down to replace the chain. This second time I wanted to
> avoid doing a major engine tear-down, so having caught the chain before it
> jumped enough to bend valves, I figured I could avoid that.) My dad came up
> with the same idea that you're suggesting -- remove a single link from the
> chain.
> Well, we removed the link, but found that doing so made the chain so tight
> that we had to use quite a lot of force to pry the camshaft back into
> position in order to get the camshaft holders back into place in the
> camshaft housing. The chain was super-tight. Anyway, as soon as we cranked
> up the engine we started hearing metallic popping sounds, so after a few
> seconds we stopped the engine, removed the valve cover, and discovered much
> to our horror that the excessive tension on the chain had broken a bunch of
> teeth off of the camshaft!
> Needless to say, I ended up having to do the full engine teardown after all,
> especially given that I had a bunch of camshaft teeth down in the bottom of
> the engine crankcase.
> What this taught me --the hard way -- was that when the chain gets
> stretched, it MUST BE REPLACED!
> However, there is a way to do that without doing a complete engine
> tear-down. The key is to get a new chain -- in this case a split chain --
> one end of which you thread through the engine, then attach a master link to
> the two ends and peen the rivets completing the loop.
> To do this, you have to remove the chain tensioner and the camshaft, break
> or cut the old chain (making sure to not get bits of metal in the engine,
> and also making sure not to drop the cut chain down in the engine -- in
> fact, you need to keep both ends of the old chain reasonably tight on the
> crank sprocket throughout the process), then bend a piece of stiff wire to
> link one end of the old chain to one end of the new chain. Then, keeping the
> chain under enough upward pressure on both ends to keep it from falling off
> the crankshaft sprocket, turn the engine over by hand until the old chain
> pulls the new chain down, around the crank sprocket, and back up through the
> engine to the camshaft housing on the other side. Once you've done all that
> -- continuing to apply upward tension on both ends of the new chain,
> disconnect the wire linking the old and new chains, and then peen the master
> link to the two ends of the new chain, creating a continuous loop of chain.
> Then put everything back together (synching up the crankshaft and camshaft,
> of course), and you've successfully installed a new chain while avoiding a
> major engine tear-down! It may be best to do this with an assistant, since
> the procedure works best with more than two hands, probably.
> You can get a visualization of a variant on this technique in this video of
> a one-cylinder Honda motorbike cam chain. The fellow in this video used a
> MIG welder on his bike's new chain, but that's because he bought a non-split
> replacement chain:
http://www.youtube.com/watch?v=IkSl0ZUDnZc
> Bruce Whiting sells split chains for 600 cars complete with a matching
> master link on his web site:
http://www.honda600carparts.com/engine.html
> Hope this helps.
> Richard
> --- In
anzhonda600owners@yahoogroups.com
ps.com> , Mark P Hatten wrote:
> > During my Z600 power improvement quest I noticed my timing chain is loose
> and probably stretched. The chain looks good, but seems to have a lot of
> play. The timing marks line up, but not perfectly. With the small belt
> pulley notch under the battery lined up on "T" , the upper cam chain gear
> horizontal scribe is almost flat, with the tiny notch in the end of the cam
> near the tach drive is slightly forward ....just a tad toward the core
> support. I know this tiny amount can make a big performance reduction. It's
> probabably 4-8* off. Not as much as one tooth off, but almost. Has anyone
> tried to just remove one chain link to shorten and tighten the chain and
> bring it back into perfect alignment? Seems like it would work. MarkPortland
> Or.
> >
www.mphspecialties.com
> > To:
anzhonda600owners@yahoogroups.com
ps.com>
> > CC:
anzhonda600owners@yahoogroups.com
ps.com>
> > From: egeiger@
> > Date: Tue, 15 Jan 2013 21:04:30 +0000
> > Subject: Re: [anzhonda600owners] Power tuning a Honda Z600
> > Can you please explain a little further about "Since
> > then, I now use an indicator to register the cam to the crank. Moving the
> chain 1 or 2 teeth in each direction made a noticeable difference in the
> performance of the engine."
> > I'm curious about this method.
> > My T on the crank pulley and notch on the cam are matched almost perfect
> maybe 1/16th an inch toward the firewall . I've also always used a test
> light to set the timing via the vacuum advance. I also feel like my car is a
> little low on power since I rebuilt
> > the engine. So I'd like to know more about what you're method is.
> > Thanks
> > Eric J. Geiger
> > ---------------------------------------
> > PRG Nocturne
> > XXX-XXX-XXXX phone
> > XXX-XXX-XXXX fax
> > XXX-XXX-XXXX mobile
> > egeiger@
> >
www.prgnocturne.com
> > On Jan 15, 2013, at 3:46 PM, "goinhm@" wrote:
> > Hi Mark,
> > I'm coming into this conversation late and I have seen the other comments.
> Here is some added info;
> > 1. The Honda Inc spec on a stock 1972 USA coupe indicates it should do the
> 1/4 mile in 22.3 seconds and have a speed of 57 mph. This measurement is at
> sea level ..... which is about where you are in Portland.
> > 2. Your compression reading of 147 psi is a bit low. It should be in the
> 160 to 165 psi range for a new (or rebuilt) engine.
> > 3. The registration of the cam to the crank is important. I used to align
> the "witness" mark on the cam sprocket and register it to the notch on the
> pulley when it was at "T" on the casing. And then one day I was noticing my
> 1/4 mile time wasn't correct
> > on a engine I had rebuilt (when I drove to work, I used to time myself on
> a road I would enter which had the 55 mph speed marker at a 1/4 mile
> distance from where I entered). I found that I had to move the chain on the
> sprocket 1 or 2 teeth. Since then,
> > I now use an indicator to register the cam to the crank. Moving the chain
> 1 or 2 teeth in each direction made a noticeable difference in the
> performance of the engine.
> > good luck,
> > Dale
> > I've been tuning for speed and power on my 1972 600cc 4 stroke Honda Z600
> hot rod. I can now go 47 mph. in 1/4 mile, up from 43 mph. last week but, it
> still seems lethargic. I got a slight miss to go away, but am disappointed
> with low top speed
> > power. Here's the back story. Fresh 20-50 wt. oil and filter. New hot NGK
> #6 plugs, new 7mm wires, new NGK 90* ends, plugs are clean after hard run,
> swapped, tested, ignition coils, new NOS points gapped correct, new
> condenser, vac. and mechanical advance
> > checked and cleaned and seem good. Timing is slightly advanced. 147 psi.
> compression on both cylinders, timing chain is sloppy but timing marks line
> up. Idles smooth, revs up good. No backfires, no misses. Smooth but low
> power. Redlines at 6500-6700 rpm's
> > no problem. Tried 2 carburetors, one old style, one new style, both are
> clean, accelerator pump works in both, float levels correct. Both carbs act
> the same. 2 psi. fuel pressure, clean fuel. All new exhaust gaskets, no
> leaks, exhau st is not plugged. Tires
> > are new and inflated to 40 psi., alignment is perfect, brakes do not drag.
> Can push car with two fingers on level surface.
> > My Subaru 360 could run rings around this slug with half the displacement.
> It just don't seem right.
> > Most 600 owners say their cars will go 70 mph. Maybe,..... with a 5 mile
> head start!.
> > What am I missing here?
> > How does one increase the jet size? Do you file the taper on the carb
> slide plunger needle?
> > I know my hood scoop does not aid aerodynamics...but, this much?
> > Help please.
https://www.youtube.com/watch?v=tyW8KQeYsfg
> > Mark
> > Portland Or.
> >
www.mphspecialties.com