TOPIC:

Well, I'm 154 miles of rolling over to 30 grand and I'm having my first major problem with the ol' 650. I went for a short ride today and when I came to a stop I noticed a vibrating noise coming from the engine. I sounded like the sound you would get by dragging a key chain over the edge of a table. It wasn't a constant noise so I rode it home.
I got back to the house and did the screwdriver as a stethoscope trick. The noise was coming from under the valve cover. I pulled the cover off and noticed that the upper roller had quite a bit of side to side play and also had a little rocking play on the shaft itself.
I have a spare cam setup I bought off ebay and a spare engine also. I checked both of those rollers and noticed the same movement but not quite as much. Is this normal??
I did notice a tiny bit of roller noise in the one from the bike, which is probably multipied when it is under tension. One of them is totally silent, this is the one I am putting back on.
Now to my question. I put an automatic slack adjuster on it last year. Should I reinstall that or put the original manually adjusted one on it.
I know I will get pros and cons on both setups. Just looking for some feedback.
Thanks,
Ride safe,
Les

I don't know the 650 engine very well but on a 900/1000, there is a front bumper/cam guide that sits at the front of the block. It has some arms that fit in notches and is held in by a phillips bolt. These things tend to harden and develop a crack in the rubber. On many of them, they are actually fully deteriorated with only the arms and small metal holder still in place with all the rubber gone into the pan. This is a normal place for engine noise and your cam chain will wear quickly when this thing goes. As far as the idler assembly (the thing on top on the cylinder head), there should be some side play as the sprocket roller just rides the shaft it sets on. The problem with this bit will be worn teeth and the rubber itself will harden. When that happens, it should be replaced alongwith the rubber pieces that dampen it. I have seen some cam chain rollers where there are sprockets get so brittle that the sprocket will detach and that would create a racket.

At 30K miles, you might want to contact z1enteprises for as much of the cam chain stuff as you can get (new) and do a top end refresh. They will have the chain, rollers, rubber bits, and perhaps the idler assembly. It ain't cheap but spending a couple hundred bucks for another 30K miles of trouble free riding is worth it. You can also put some valve stem oil seals in and some new rings and engine oil seals and restore the bike's original performance... If you have a down season wherever you live, this would be the time to do this job. This job will take an experienced mechanic a little over a day depending on how much engine clean up and how hard the gaskets surfaces are to clean.

Thanks for the reply WG. I put it back together with the softest rubber blocks of the 3 sets I had and used the top roller with the least play.
It cured the noise for now. I see Jeff does have new parts which I'll get for my winter rebuild. In Maine it seems the winter down time is longer than the yearly riding time. I'll have plenty of time for a rebuild this winter.
Thanks again,
Les

Post edited by: The Milkman, at: 2006/08/17 10:03

Wasn't there a post some time back, about Kaw not having any more of the cam chain adjustment items for the 650? I thought Jeff posted it...
Never mind, it was this link about the rear cam chain adjuster.

Post edited by: OKC_Kent, at: 2006/08/17 11:03

The auto cam chain tensioner is considered a flop and the worst of all the tensioners. The manual doodaa is not hard to operate, unpinch pinch bolt at every service whilst cam is in correct position (see manual or posts for correct position, if stuck TDC will work fairly well).

As far as I remember the roller sits on two rubber chunks with steel plates as well. Mine is rock solid no movement when bolted down (very easy to drop bolts down cam chain shaft tho'), except for some play in the roller itself. Personnally I should think the roller would do 50k miles without too much trouble, but like others said, the rubber dampers harden and brake off, fairly cheap to replace.

Not to knock others but I wouldn't touch the head rings etc. unless there are signs of low compression, smoke etc. At idle cam chain rattle can be severe if carbs are not blanced and cam chain slack is not adjusted.

Great bikes, just wish it was easier to wheelie.

Cactus, My intention wasn't to make busy work for the Milkman but if I take off a cylinder head and block, I just automatically measure bore to piston clearance and rering after boring if things are in spec. I also generally disassemble the cylinder head, clean and put some new seals in as a matter of course. With 30K miles, it would be prudent to do routine maintenance type stuff if the engine is apart and if the cam chain bits are getting noisey, I would look at the front bumper thing in the block and just replace the rest. Z1Enterprises.com can get you all new rubber bits/cam chain and some of the other parts at a fairly reasonable price. It only takes me a few hours work to ensure another 30K miles of trouble free riding so the time and money spent are well worth it to me. I see lots of folks asking about how far these engines can go and 30K miles would be about what I would estimate on a top end rebuild... perhaps more; perhaps less, depending on how the bike is maintained and ridden.

Not a problem to me at all about the busy work WG. I appreciate your and everyone else's input as always. I was planning on a rebuild this winter anyways. I plan on staying stock as possible. I've found suppliers for all the parts that I think I will need. All expect for a hivo chain, the lower one for the tranny. God knows if they are even available. I'll check the one on my spare block may just use that one if it's tighter than the one in the current engine. There is quite a bit of slop between the crank and the output sprocket and I doubt if the majority of it is in the gearing itself but time will tell.
Thanks again,
Les