New 1980 Kz750twin owner with help questions. Carb, Electric, parts?

[iceshark]

What a great forum. I was an avid 1979 Z1R owner for years. Then the usual story. Got out of bikes for about 15 years. I just picked up a very well cared for 1980 Kz750 twin LTD with only 10.000 miles on it and in great cond for its age. The owner had her parked in garage last 10 years and due to his age deceided to sell it to me for $250.00

He was very open about it having carb issues. He has in fact bought an extra exact Mik carb set from a junk yard to have rebuilt and replace the one on it. Just never did it. I know have that complete extra set.


Here is what I have done to get it running. I still have some needs and some questions for you experts.

I flushed all old oil out and replaced with new Kawasaki 10-40 motor oil. I also changed filter. Boy that was fun!

2.I changed brake fluid and flushed.

3.I flushed gas tank and purged all old gas. Tank is still in perfect shape with no sign of varnish or rust. I cleaned petcock and changed fuel lines.

4. I replaced battey.

5. Replaced spark plugs.

have dont other cosmetic stuff but thats about all in the restore. Time to start it.

Got it started and it sounded good. Only I could not get it to idle with Choke down and off. Had to keep choke about 1/4 engaged. Was able to drive and it felt strong. Just no idle.

Then I smelled gas and see gas coming from I believe a backflow hose or carb onto ground. Bike died and could not get restarted.

I did run Seafoam in gas and sprayed carb cleaner in. But I suspect float is stuck or other carb problem as the old man stated.

Walked bike back home.

Here is the questions,

1. Does this sound like i must rebuild one of my sets of carbs? Could I just clean the set that is off bike and try it? I cant find rebuild kit. They only list a KandN and other for 1976-1979 and 1982-1987 I was at Bike shop and the parts guy was even bewildered why no listing for my year??? Its a Mik 38s I believe.
2.Are the Carbs hard to take off? Look easy, just wondering

3.When I put in new battery I was baffled as a red wire was on Negative and Black on Positive on the Battery. I traced and the Red one infact is grounded to motor and Black one is on what looks to be a solinoid. Is that stock or did someone just want to confuse the next owner of this bike. NAMELY ME!

4.I am not sure the Battery is charging. I see actually two wires hooked to NEGATIVE on the battery??? Isnt according to the wireing diagram the second wire supposed to be on the positive side with the positive wire? I wonder if the last bike owner put it on wrong as the color messup I just explanined with the black and red. How can I test for charge.

5.My nuetral light is not working. Is this a bulb or is it not fixable?

6.Last I am looking for some parts. Mainly a new seat as this one is beat up and a new lock for seat and helmet holder as someone took this set off and toosed it. Plus I need some stock pipes as this has glasspaks on it and I would like to go stock.

Also, Is it normal for the starter to make battery go dead fairly fast on these models. Even with new Bat it seems to drain battery fast.

Sorry for the long post. I just am a newbie here and would love some help!
Thanks
Tod in Marysville.

[Alizard]

Originally Posted by iceshark

I just picked up a very well cared for 1980 Kz750 twin LTD with only 10.000 miles on it and in great cond for its age. The owner had her parked in garage last 10 years and due to his age deceided to sell it to me for $250.00

What a steal.

Originally Posted by iceshark

Got it started and it sounded good. Only I could not get it to idle with Choke down and off. Had to keep choke about 1/4 engaged. Was able to drive and it felt strong. Just no idle.

Then I smelled gas and see gas coming from I believe a backflow hose or carb onto ground. Bike died and could not get restarted.

The float in the carb is sticking down and not rising to cut off the fuel flow. Cleaning the carbs will fix it.

Originally Posted by iceshark

1. Does this sound like i must rebuild one of my sets of carbs? Could I just clean the set that is off bike and try it? I cant find rebuild kit. They only list a KandN and other for 1976-1979 and 1982-1987 I was at Bike shop and the parts guy was even bewildered why no listing for my year??? Its a Mik 38s I believe.

Keyster makes them. Try loudfastugly.com.

loudfastugly

They have the kits for all the "B" model 750 twins. My 1979 twin has BS-38's and those kits fit them. Not sure if they fit yours.

Originally Posted by iceshark

2.Are the Carbs hard to take off? Look easy, just wondering

Not really

Originally Posted by iceshark

5.My nuetral light is not working. Is this a bulb or is it not fixable?

There should be a bulb.

Originally Posted by iceshark

6.Last I am looking for some parts. Mainly a new seat as this one is beat up and a new lock for seat and helmet holder as someone took this set off and toosed it. Plus I need some stock pipes as this has glasspaks on it and I would like to go stock.

I've never seen a stock set for sale, they will be very expensive.

Originally Posted by iceshark

Also, Is it normal for the starter to make battery go dead fairly fast on these models. Even with new Bat it seems to drain battery fast.

Sorry for the long post. I just am a newbie here and would love some help!
Thanks
Tod in Marysville.

Not normal. Mine will crank the heck out of it.

[Alizard]

Hmmm..... I looked on Bike bandit and didn't see a 750 twin for 1980? You sure about the year?

[iceshark]

WOW! Thanks a bunch Bounty hunter

Yes its a 1980, It has 2 BS-38s on it and I have another set of 38s. Thats why I am so confused. I had Kawi dealer here look up parts list and he claims the 1979 twin has different carbs then my 1980 twin. Sounds like you do have the same carbs.?

I am looking here at my stock owners manual as well. (yes he had pristine manual still under seat) Its says its a 1980 Kz-750g twin and it has Mik Bs-38 carbs. So if this is the case then the 1979 kit should be the same.


So your thinking I may be able to free up floats? Cool

LOve the fast help!

[gpzrocker]

If you haven't been to KZrider.com - Home, then they are a wealth of info also.

[elr658]

I find us to be as good and our site is MUCH easier to navigate. You have the hard parts either done or not needed. Reclean the carbs and you should be good to go. Remember, those tires are harder than Chinese Arithmetic so your spending isn't done yet. You're probably dealing with frozen brake calipers too. Welcome. Z1 Enterprises has what you need. Jeff is a board member and offers terrific customer service. (I am not affiliated, tell him you are a member here too)

[OKC_Kent]

Originally Posted by elr658

I find us to be as good and our site is MUCH easier to navigate.

Hey I'll stir the pot and disagree on one point anyway. This site IS easy to navigate, (and that's a sore point on KZrider which has it's frustrations); but it's just a broad forum for every Kawasaki, and that's everything, cruiser, dirt, ATV, Sportbikes, etc and I've noticed the riders here are basically on newer machines, and very social, especially in the cruiser area.. Nothing wrong with that, I like it, but on KZrider.com we are just about KZ's. We have a Filebase that has a wealth of technical files and papers just about this line of machines.

On this site we just have the Vintage forum, nothing to download, like manuals, wiring diagrams, tips, tricks, etc... KZRider.com tends to be a bit more technical, as we just deal with one series of bikes from Kawasaki.

Most of us hanging in 'Vintage' are on KZRider anyway, but the two or three people who know a lot about the 750 twins are on KZrider. If people (me included) are directing new members to KZrider.com it's only because that is the place to go for KZ's.

ELR, I'm surprised you're not a member there, are you?

Kent

[antiq]

Originally Posted by iceshark

What a great forum. I was an avid 1979 Z1R owner for years. Then the usual story. Got out of bikes for about 15 years. I just picked up a very well cared for 1980 Kz750 twin LTD with only 10.000 miles on it and in great cond for its age. The owner had her parked in garage last 10 years and due to his age deceided to sell it to me for $250.00

He was very open about it having carb issues. He has in fact bought an extra exact Mik carb set from a junk yard to have rebuilt and replace the one on it. Just never did it. I know have that complete extra set.


Here is what I have done to get it running. I still have some needs and some questions for you experts.

I flushed all old oil out and replaced with new Kawasaki 10-40 motor oil. I also changed filter. Boy that was fun!

2.I changed brake fluid and flushed.

3.I flushed gas tank and purged all old gas. Tank is still in perfect shape with no sign of varnish or rust. I cleaned petcock and changed fuel lines.

4. I replaced battey.

5. Replaced spark plugs.

have dont other cosmetic stuff but thats about all in the restore. Time to start it.

Got it started and it sounded good. Only I could not get it to idle with Choke down and off. Had to keep choke about 1/4 engaged. Was able to drive and it felt strong. Just no idle.

Then I smelled gas and see gas coming from I believe a backflow hose or carb onto ground. Bike died and could not get restarted.

I did run Seafoam in gas and sprayed carb cleaner in. But I suspect float is stuck or other carb problem as the old man stated.

Walked bike back home.

Here is the questions,

1. Does this sound like i must rebuild one of my sets of carbs? Could I just clean the set that is off bike and try it? I cant find rebuild kit. They only list a KandN and other for 1976-1979 and 1982-1987 I was at Bike shop and the parts guy was even bewildered why no listing for my year??? Its a Mik 38s I believe.My 78 carbs cleaned up easily w/o rebuild
2.Are the Carbs hard to take off? Look easy, just wondering
No not hard to get off.
3.When I put in new battery I was baffled as a red wire was on Negative and Black on Positive on the Battery. I traced and the Red one infact is grounded to motor and Black one is on what looks to be a solinoid. Is that stock or did someone just want to confuse the next owner of this bike. NAMELY ME!
Someone must have replaced wires
4.I am not sure the Battery is charging. I see actually two wires hooked to NEGATIVE on the battery??? Isnt according to the wireing diagram the second wire supposed to be on the positive side with the positive wire? I wonder if the last bike owner put it on wrong as the color messup I just explanined with the black and red. How can I test for charge.

5.My nuetral light is not working. Is this a bulb or is it not fixable?
Probably the bulb. unscrew the ring on the ignition switch and the cover lifts off.If it's not the bulb the sending unit wire is next to your front sprocket under the left side cover.
6.Last I am looking for some parts. Mainly a new seat as this one is beat up and a new lock for seat and helmet holder as someone took this set off and toosed it. Plus I need some stock pipes as this has glasspaks on it and I would like to go stock.
Best of luck finding a new seat.I recovered mine
Also, Is it normal for the starter to make battery go dead fairly fast on these models. Even with new Bat it seems to drain battery fast.
Sounds like the new battery wasn't fully charged.
Sorry for the long post. I just am a newbie here and would love some help!
Thanks
Tod in Marysville.

Ohio?

[OKC_Kent]

Originally Posted by iceshark

3.When I put in new battery I was baffled as a red wire was on Negative and Black on Positive on the Battery. I traced and the Red one infact is grounded to motor and Black one is on what looks to be a solinoid. Is that stock or did someone just want to confuse the next owner of this bike. NAMELY ME!

4.I am not sure the Battery is charging. I see actually two wires hooked to NEGATIVE on the battery??? Isnt according to the wireing diagram the second wire supposed to be on the positive side with the positive wire? I wonder if the last bike owner put it on wrong as the color messup I just explanined with the black and red. How can I test for charge.


Also, Is it normal for the starter to make battery go dead fairly fast on these models. Even with new Bat it seems to drain battery fast.

Sorry for the long post. I just am a newbie here and would love some help!
Thanks
Tod in Marysville.

Your battery may not be charging due to a few things like dirty connections or no connections. Look at a wiring diagram and follow the wires from the battery to see exactly where they go. As antiq said some previous owner may add new wires and not use the same color as stock. When you get it running get a volt meter and measure across the battery terminals (DC Voltage setting); at idle it should be 12.5-13.5 volts. At a higher rpm you should see about 14.5 volts. If you don't have that, then start cleaning connections in the charging circuit. Also, wires and battery cables may look good on the outside but be corroded under the insulation. Measure the resistance of a wire, if it's good the resistance should read very very low, or zero. If it's higher then clean the ends and measure again. If still high then replace the wire. Do the same for the wires in your starting circuit, see if that helps.

[elr658]

Of course, I am...elr658 there too. BUT, except for the Zephyr question I just asked, I have NEVER asked a technical question in the five years and ten boards I'm on.

I have answered about 20,000 of them, though.

[iceshark]

Again awesome site and replys.

How come I have heard from many too replace tires>? Are they unsafe? They look like new and have no cracking?

Front brake works well. Rear does not and indicator is all the ways back on gauge and when rear brake applied it goes back off the scale. Bet thats a fun job to fix....


I will test electronics tonight. I suspect that extra wire hooked to ground is incorrect or is supposed to go on positive with wire to starter solinoid.

Thanks!

[A2rider]

Somewhere on the sidewall of the tire there is a manufacture date. This will give you a clue to whether you want to risk any miles on those tires.

[antiq]

I wouldn't want to risk a flat or blowout on a bike. I've run my share of maypops on cages. Not on bikes.

[Alizard]

Originally Posted by iceshark

WOW! Thanks a bunch Bounty hunter

Yes its a 1980, It has 2 BS-38s on it and I have another set of 38s. Thats why I am so confused. I had Kawi dealer here look up parts list and he claims the 1979 twin has different carbs then my 1980 twin. Sounds like you do have the same carbs.?

I am looking here at my stock owners manual as well. (yes he had pristine manual still under seat) Its says its a 1980 Kz-750g twin and it has Mik Bs-38 carbs. So if this is the case then the 1979 kit should be the same.


So your thinking I may be able to free up floats? Cool

LOve the fast help!

The kit should work, but you might be able to fix it without a kit. Clean the carbs and take the floats, needles and seats out. Polish the needle tips and float seats to get them clean, make sure the floats move freely. Set the fuel level in the bowls with the clear tube method. Should work OK then.

[iceshark]

Thanks again. Also, I do have the stock pipes all the way back to mid bike. Its the mufflers that were replaced with glass packs. Can I still find mufflers to put back into pipes?

[antiq]

You can adapt most any muffler you like on there. Not sure if the stock mufflers are available. I'm running a 2-1 set up on mine. This forum is all about the twins.
THE KAWASAKI TWIN OWNERS FORUM :: Index
You may want to check it out.

[iceshark]

Originally Posted by antiq

You can adapt most any muffler you like on there. Not sure if the stock mufflers are available. I'm running a 2-1 set up on mine. This forum is all about the twins.
THE KAWASAKI TWIN OWNERS FORUM :: Index
You may want to check it out.

Thanks! Just joined.

Okay the carb update, I took off the ones that had issues with leaking major gas and no idle. I took the spare set of same carbs he gave me. I took off bottom cover and cleaned the jets and bowl. Sprayed rest of card, did not take off round tops. Did not know if I would need too. Have no diagram of carbs.

Put on the other set, was easy enough to get on and off bike once I found you can retract rubber air grommets back into airbox.

I marked to the best of my ability the placement of the throttle linkages. I think I got them back on close.

Bike fires up but will not idle under about 1600 rpms and I can feel and hear backfires at the pipes. Not a clean idle. Seems these carbs may have problems too. but different ones. No leaking gas ect ect.

Next I will try and find rebuild kit and clean up my original one on bike.

Is there any other adjustments I may need. Wish I could find a manual for this bike.

[Alizard]

Originally Posted by iceshark

Thanks! Just joined.

Okay the carb update, I took off the ones that had issues with leaking major gas and no idle. I took the spare set of same carbs he gave me. I took off bottom cover and cleaned the jets and bowl. Sprayed rest of card, did not take off round tops. Did not know if I would need too. Have no diagram of carbs.

Put on the other set, was easy enough to get on and off bike once I found you can retract rubber air grommets back into airbox.

I marked to the best of my ability the placement of the throttle linkages. I think I got them back on close.

Bike fires up but will not idle under about 1600 rpms and I can feel and hear backfires at the pipes. Not a clean idle. Seems these carbs may have problems too. but different ones. No leaking gas ect ect.

Next I will try and find rebuild kit and clean up my original one on bike.

Is there any other adjustments I may need. Wish I could find a manual for this bike.

I have seen manuals on ebay.

There is a guy named WiredGeorge on this site:

KZrider.com - Home

that is a carb wizard. You just send him the carbs and they come back ready to rock. No screwing around.

[antiq]

Biquetoast on the twin forum has pdf manual.