TOPIC:

Looks to me like somebody replaced the tensioner and didn't quite fully grasp what we was doing. I'd almost guarentee that isn't stock. Probably a ratchet-type (judging by the small side protrusion and lack of side bolt), mostly likely with the wrong spring.

CAM CHAIN TENSIONER DEBATE OPINION INCOMING!!!!

In my opinion, the weak link in the whole "KZ1300 cam chain tensioner" issue is just that- the tensioner. The biggest failing is that it isn't a positive "ratchet" type one. It uses ball bearings, which are a plus in that they allow for minute adjustments as the cam chain stretches, but don't lock as positively as the ratchet types. Also, the spring pressure on the actual tension is really pretty low- it's not tightening the chain up, just (barely) taking out the slack. IF the chain is at the correct tension, everything else- the nylon gear, the rubber roller, etc.- works just fine.

The problem arises when people try to swap out the stock tensioner with a manual one, and aren't sure what they're doing. You end up with either too much slack or too little, then everything else down the line gets chewed up.

My eventual goal is to take the side bolt out (used when initially setting the stock tensioner into the motor) and replace it with one slightly longer, long enough to tighten down on the tensioner bar/pin/whatever, and lock it into place. Then, every time I do an oil change, loosen it a bit, let the spring take out any slack that may have accumulated, then tighten it back up, so it doesn't (God forbid) kick back and bend me some valves.

To each his own, of course. Take it as you will.

Thanks for the replies guys.

I took out the bolt in the cam chain tensioner to see what was behind it because I didn't understand how it works or even if that actually was the tensioner. It has a long skinny spring and rod behind it so I guess that makes it automatic? Now to figure out if there is any adjustment left.

Kawboy: So you say that gear should be replaced? I don't know what you mean by multiple teeth on the same tooth? Do you mean the dark marks across it? If the head has to come off is there something else I should be doing while that happens? Performance mod opportunity?

So the first thing we'll do is check the valve clearances. Sounds straightforward and I'm sure Tom will understand all of this far more than I do. Stupid question but will this tell me if there is a bent valve etc? Will it explain my compression issue?

Lucien, I've never experienced what you are explaining with the hydrolock. I hope the old owner didn't either. If it had of happening to me would gas have ended up in my oil? If so I'm good since I owned it

As far as the jets go. Hell, the carbs are off now and the header is already on its way so I'm already in too deep. Might as well do it right.

Thanks again.

Basically, that gear is pretty ratty. The top edge of the teeth should be smooth, lengthwise. It the teeth are thin enough to get ratty along the top, you really should get it replaced.

If a hydrolock happened, yes, you could get gas down into the oil. It could've dumped it down into the exhaust as well, so that's not an end-all be-all.

Valve clearances won't explain things like a bent valve, but if they're off on the bay cylinders, you know that valves are to blame.

A bent valve could get stuck open, or not close all the way, accounting for the low compression numbers. Actually seeing if it's bent would probably be more obvious from the underside, which means you'd have to take the head off.

If you DO decide to take the head off, you can get quite a bit more information about what's going on. A visual check for a bent rod would be easy, along with bent valves. Unless you're blowing coolant out a tailpipe, I don't think a blown head gasket would be your issue, although you can't rule it out. If you can afford it, a full valve wouldn't hurt. Lapped, new seals, etc. There might be some power mods swapping camshafts around and such, but not much you can do JUST taking the head off. (I've heard of porting heads, but I have no clue what that entails, or potential gains from doing so)

While you have it as you do right now, do another check- in the manual, in the section for re-assembling the head, they have the write-up on how to set the camshaft timing- it's basically lining up a mark with the top of the head, then counting links to a mark on the other camshaft. In any case, do this. This will let you know if a camshaft slipped a tooth, which is never good. Don't turn the motor over without a cam chain tensioner, though.

Ok. Thanks for the explanation.

Am I taking a gigantic risk if I were to leave that gear in their until the end of the season? This is provided the compression is a minor fix and comes up. Or are we wasting a lot of effort if we don't take the head off now? I don't know what is involved in terms of time and money for these procedures on this bike.

I do know porting can give good gains but I believe they work best with upgraded cams, springs etc. I'm not sure any of that is even available for the 1300.

These guys did my 12 and they have a good explanation of head porting on their site.

carpenterracing.com/headporting.htm

Kawboy wrote: I'm looking at your 3 pic and I see UGLY. The nylon gear in that pic is part of the cam chain tensioner system and it's not suppose to have multiple teeth on the same tooth. The cam chain has been flopping around and it's cut the teeth. You need a new gear. Bad news is the head has to come off to replace. Good news is the gear is still available from Kawasaki at around $55 Canadian.Some members have opted for the aftermarket LISKA steel gear at around $110 U.S. I hesitate to use it because I'm hearing reports of noisy for the first 200 miles and then they quiet down. That suggests to me that something is wearing in and mating. Would that be the gear wearing in or the cam chain?

The tensioner looks like a modified stock tensioner. Some people have drilled a hole in the back end and tapped then inserted a LONG FULLY THREADED BOLT with a lock nut . Then manually adjust it and LOCK the bolt in its place. Yours looks like it just has a bolt in it, Where's the adjustment? I would suggest you search EBay for "KZ1300 tensioner" and you should find an APE tensioner for around $45 U.S. I prefer the manual one over the modified ZXR 1100 one. (to each his own)

Checking the valve clearance- If the cam lobe is pointed up then the base circle of the lobe is sitting over the valve bucket shim. At that point you can check the clearances with feeler gauges. I just prefer turning the crank over until I have the cam where I want it and check the clearance. The manual tell you to align the crank at 3 different points and then you can check a number of clearances at each point. I just prefer putting the cam where I want it and checking. I think it's easier.

Hope this helps, (sorry to see the nylon gear in bad shape)

KB

Sorry for the confusion regarding the multiple teeth on the same tooth. The profile of the tooth on the nylon gear should look exactly like the profile on the camshaft tooth only on a smaller diameter. Your teeth on your gear have had their faces shredded and now each tooth has 3 teeth ( hey Scotch, guess I should have been a dentist). Our member Brandonsmash posted a picture of his nylon gear just 4 days ago and it looked like this.

You need to do the gear, nylon or steel replacement, you need to do it and the head is coming off.

If you have a compression tester that has a hose that screws into the head and couples up with a hose with the gauge, you can take the hose and screw it into the head, set the crankshaft with that cylinder on top dead center and apply compressed air from an air compressor to the hose. PLEAASE NOTE_ the engine can at any moment turn over so keep your fingers out of any possible moving parts!!! and listen for the air escaping from the carb (tight intake valve) from the exhaust (tight exhaust valve or bent valve, from the oil filler cap (bad piston rings) or bubbles in the rad (bad head gasket) It's nice to have the leak down tool for measuring the minor leaks and quantifying the results, but when you're looking for a gross leak, you can just rough it by doing this test. Then when you split the engine and repair, you know exactly where to look.

As far as mods go, it's difficult trying to get big numbers out of a long stroke engine. Your restrictions are limited by the size of the valves. Big bore engines have a lot more room for valves and will breathe better. The camshaft in this engine is fairly mild and some minor improvements can be seen with possibly a slightly more radical camshaft with maybe .375" lift and possibly 270 deg. duration. There's a company in California called Megacycle who will hard face your cam and regrind to a new profile. They show 3 profiles for the KZ13. There's a cost to doing a cam change like this and you'll end up giving up torque for more horsepower at a higher rpm, so for the average guy just out riding, I'd rather have the torque for passing in the same gear rather than having to downshift every time you want to get on it. As a stock engine, the KZ13 is pulling 100 hp per liter and that's really good for a long stroke engine. The Hayabusa is a big bore engine 81mm bore and 65mm stroke and s pulling 195 hp which is around 150 hp per liter. The problem is that the hayabusa pulls these numbers at 9800 - 10200 rpm where the KZ pulls the big numbers down at 6500 rpm (for torque)

Thanks Kawboy.

I understand what you mean about the gear teeth. What would have caused my gear to wear out like this? Bad adjustment or just age? Cam chain stretch? All of the above? Do I need to replace the cam chain as well?

I agree with you. I'd rather have my power down low than needing to downshift and make it scream. I drive a TDI because its awesome driving a 4 cylinder, fuel saving car that doesn't need to downshift to third to pass a truck going up a hill. Just roll on the throttle.

Thanks for the info on the air compression test.

This is a real bummer so far.