A few questions from a noob Valves 82 KZ750 h3 ltd

martin_csr wrote: Just a suggestion.... you could put an airbox back onto the bike.

Man, you have no idea how bad I want to replace the airbox. It has been raining a lot lately and with the shit pods a short downpour stops me dead in the my tracks. I have been scouring ebay for an airbox, but have had little success. Are there any other models that will fit my bike?

Again thanks for the help. I will be checking the compression, and hopefully putting in some new plugs this evening.

Another question, the PO dirlled out the exhaust, I doubt that is helping my bike at all. I was thinking about going for a 4-1. My options are the Mac or V&H does it matter or is it all preference?

Any KZ750-4 airbox should fit. Also, KZ700. ZN700. And 81-83 650-CSR.
The closest matches are the 750-E/H & 650-H CSR. There are minor differences in some of them, but shouldn't be problematic at all: some have extra holes w grommets for the carburetor overflow tubing (such as the 750-H3); a few have decorative covers on the sides (eg, ZN700).
The stock airbox on my 81 650 is embossed w KZ750, so it's actually a 750-4 airbox.

Airbox ducts. New oem ducts are available at various places & Z1Enterprises.com (probably cheaper at RonAyers etc).

Mufflers. Other than the holes the po drilled, what's the condition of the exhaust?

martin_csr wrote: Any KZ750-4 airbox should fit. Also, KZ700. ZN700. And 81-83 650-CSR.
The closest matches are the 750-E/H & 650-H CSR. There are minor differences in some of them, but shouldn't be problematic at all: some of them have extra holes w grommets for the carburetor overflow tubing (such as the 750-H3); some have decorative covers on the sides (eg, ZN700).
The stock airbox on my 81 650 is embossed w KZ750, so it's actually a 750-4 airbox.

Airbox ducts. New oem ducts are available at various places & Z1Enterprises.com (probably cheaper at RonAyers etc).

Mufflers. Other than the holes the po drilled, what's the condition of the exhaust?

Other than the holes it is in great condition. I was thinking about just putting new mufflers on, but have done any real research on it.

martin_csr wrote:

Nebr_Rex wrote: Not the seals, just the valves them selves.

The statement was in regards to the oil consumption. I think low compression could be either/or.
At any rate, he's got some checking to do.

+1

martin_csr wrote: Any KZ750-4 airbox should fit. Also, KZ700. ZN700. And 81-83 650-CSR.
The closest matches are the 750-E/H & 650-H CSR. There are minor differences in some of them, but shouldn't be problematic at all: some of them have extra holes w grommets for the carburetor overflow tubing (such as the 750-H3); some have decorative covers on the sides (eg, ZN700).
The stock airbox on my 81 650 is embossed w KZ750, so it's actually a 750-4 airbox.

Airbox ducts. New oem ducts are available at various places & Z1Enterprises.com (probably cheaper at RonAyers etc).

Mufflers. Other than the holes the po drilled, what's the condition of the exhaust?

The earlier KZ650s look similar, another option?

.

The earlier 650 airbox holes are different, because the ducts are different --- the middle holes are smaller than the outer. I do not know if the offset is the same or not. Z650Spirit over at the KZ650.Info site re-cut the holes to accept some ZR750 carburetors.

Muffler holes. If the holes are a handy size, you might be able to plug them. I was able to re-drill the holes made by the po & cut a couple of threads then use brass plugs w permanent locktite.

drilled eggzost.

Turns out that I am just plain stupid. My center stand doesn't get my rear tire off the ground so I always either put a board under it, or do it at the lip of my garage. Anyway I realized today that the bike wasn't at center which was causing the oil level to appear low. Made sure it was nice and level and then check out the oil level and it was right where it was supposed to be. Stupid...

I have been searching the site, and found a little bit of information, regarding the rev range of these ltds. I lot of people have said these KZs are pretty rev happy. When highway riding 70-75mph I am right under or above 6000rpms. Is that normal. I start to freak out if I approach 7000rpms. I have 13 front and 33 rear sprocket.

My package from Z1 should arriving on Friday! I will be posting if I run into any trouble. Thanks for all the help!

Id sell you my air box if you really wanted one.

I survived the valve check. I have a total of four valves total that are out of spec; two of which were so tight I couldn't even get my smallest feeler gauge to fit. I removed the shims and found that they had no size markings on them. I took the shims to my local vintage bike shop, and they tried to help me out, but only had shims the same size or bigger.
I don't own any calipers, and the shop didn't have any calipers that were able to give an accurate reading of the shim size. We did however, find out that the smallest shim I had was a 2.45. I am going to order a few shims smaller than the 2.45 and hope that can get get everything within spec. Any ideas as to what sizes I should order would be great.
Because a few of the valves had no clearance I am guessing it is just going to be a trial and error and time consuming process.

On another note, I am highly considering ordering a set of the UNI filters. Are they really worth the money, will they be that much better than the crap EMGO filters I have?

You might consider buying a HotCams 13mm shim kit. From 1.80 to 3.20mm in 0.05 increments and 3 shims from each size. 70 bucks.

undiablo wrote: You might consider buying a HotCams 13mm shim kit. From 1.80 to 3.20mm in 0.05 increments and 3 shims from each size. 70 bucks.

Thanks, I saw those and wasn't sure if they were something that would work for my bike. I will have to bick up one of those sets.

martin_csr wrote: The earlier 650 airbox holes are different, because the ducts are different --- the middle holes are smaller than the outer. I do not know if the offset is the same or not. Z650Spirit over at the KZ650.Info site re-cut the holes to accept some ZR750 carburetors.

Muffler holes. If the holes are a handy size, you might be able to plug them. I was able to re-drill the holes made by the po & cut a couple of threads then use brass plugs w permanent locktite.

drilled eggzost.

probably a dumb question, but where did you get the plugs?