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wickedwhip21
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25 Posts
Discussion Starter #1
I have been working on this bike for a while now, VN700. Was running good, but I was having tranny issues(Not shifting into second.) I took the bike for a ride around the block last week thinking I got it straight(replaced clutch cable and finally got it adjisted properly). I took it down the street, and it wouldn't go into second. When I turned around to come back, the bike died on me right before I got in the driveway. I pulled in the clutch and coasted in. I went to start the bike again the and it got about a havlf turn of the crank and stopped. It acted like a dead battery. I put the charger on over night, came out the next day tried to start if with a fully charged battery, and the same thing. It is like it is locked up. I popped the stator cover off and turned the rotor bolt. With a little force the crank came free. I turned it a couple of times pretty easily, then it locked up again. Any suggestions?? Could that be the clutch causing that? Oil is just below sight glass, but I recently had engine out with oil drained for a while to replace dampeners. Any suggestions???:confused:
 

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Linkmeister Supreme
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7,960 Posts
I have been working on this bike for a while now, VN700. Was running good, but I was having tranny issues(Not shifting into second.) I took the bike for a ride around the block last week thinking I got it straight(replaced clutch cable and finally got it adjisted properly). I took it down the street, and it wouldn't go into second. When I turned around to come back, the bike died on me right before I got in the driveway. I pulled in the clutch and coasted in. I went to start the bike again the and it got about a havlf turn of the crank and stopped. It acted like a dead battery. I put the charger on over night, came out the next day tried to start if with a fully charged battery, and the same thing. It is like it is locked up. I popped the stator cover off and turned the rotor bolt. With a little force the crank came free. I turned it a couple of times pretty easily, then it locked up again. Any suggestions?? Could that be the clutch causing that? Oil is just below sight glass, but I recently had engine out with oil drained for a while to replace dampeners. Any suggestions???:confused:
If it really is starting to lock up, I`m wondering if you have a broken piston ring, or a partially broken cam chain link. Maybe a pin half broken off and the chain plates sticking out and hanging up??? Hope I`m wrong and that it is something easier to fix, but that is what comes to mind.:(
 

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wickedwhip21
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25 Posts
Discussion Starter #3
Any sure way to tell of any of those? Feels like compression is there. No wierd noise coming from it. I reset the ACCTs, hoping that was the problem. Not it though.
 

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Linkmeister Supreme
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Any sure way to tell of any of those? Feels like compression is there. No wierd noise coming from it. I reset the ACCTs, hoping that was the problem. Not it though.
I turned it a couple of times pretty easily, then it locked up again.
My mistake. From the previous post, I thought your engine was locked now, and wouldn`t turn again.

A compression test should/may give an indication of a broken ring.

However doing an accurate compression test, comparing the two cylinders, is not possible if the starter will not reliably crank the engine over for several revolutions.
Can you boost the battery and get the starter to crank the engine over?

I have never done a cylinder *compressed air leak down test*, but excess air escaping through the crankcase would indicate leakage past the rings.

It`s premature based on my knowledge to suggest pulling the engine yet, so let`s see what other ideas surface in the next day or two. :)
 

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wickedwhip21
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25 Posts
Discussion Starter #5
OlHoss - Thanks again for the info. I will try getting at it this evening. Bike is on charge now, and I have a car battery I can hook to it as well. Something is up. I just don't get why it would turn freely for several revolutions with the socket wrench, but when I go to start it, it locks up or hangs up I should say. Do you think it could be the starter?:confused:
 

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Someone correct me if I'm wrong but...
you should be able to roughly check the upper chains if you remove the spark plug cups on both heads.
you should be able to feel the chain as you manually turn the crank...
I haven't tried this but seems to make sense after tearing mine down, it's right there.
 

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Linkmeister Supreme
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OlHoss - Thanks again for the info. I will try getting at it this evening. Bike is on charge now, and I have a car battery I can hook to it as well. Something is up. I just don't get why it would turn freely for several revolutions with the socket wrench, but when I go to start it, it locks up or hangs up I should say. Do you think it could be the starter?:confused:
Could be a couple of things on the starter that I can think of.
1.- a dead segment on the comutator and windings. If the starter stops rotating with the brush on the dead/shorted out segment the starter won`t operate.
Possible worn down commutator and/or brushes too?

2.- There is a starter clutch assembly and gears that I do not totally understand. I believe the clutch engages in one direction, and freewheels when not engaged.
Anybody else have some suggestions here? I`m getting in over my pay grade.:(
 

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Premium Member
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1,803 Posts
I think it could be either the starter motor clutch, starter motor idle gear, or the starter motor spur gear. JMO
 

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wickedwhip21
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25 Posts
Discussion Starter #9
Here is where I am at now. I took a few more turns by socket wrench, then put some oil back in it. I took several turns with the wrench with all of the spark plugs out, and the spark plug sockets out to watch the cam chains. The chains look good, and I watch the valves that I could see from the spark plug holes open and clothes. But every now and again it would hang again. I went ahead and hooked the battery back up, and gave it a few cranks with the spark plugs out. It would hang up every so often, so I would free it with the socket wrench. I also tapped on the starter a few times. In now spins pretty freely. I put it all back together with the plugs in, and tried to fire her up. On a few of the revolutions it sounded like there was no compression on the rear cylinder, but now sounds like it is good. Battery died before I could get it fired. I took my battery the other day to Advanced Auto to see if it was good. They said yes, but I am wondering. It didn't hold it's charge too long. It is charging now. I guess I will take it to another shop to have it load tested. My multimeter was getting 12.8 volts when I took it off charge. After trying to start for about 5-10 min it is down to 11.83. So we shall see. Thanks for al of the advice. I think if I get it running, I will drain the oil again and pull apart the starter to lube it up.
 
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I had a problem with the starter clutch on my 89 750. The starter would sping but there wasnt any engine turnover to fire it up. So after alot of checking with different people. I came to the conclusion it was a starter problem or some kind of bearing or bushing issue. I took it all apart and found, by testing on the bike the starter, I could see the starter clutch gear and harmonic balancer gear was spinning but the starter cluthc was not locking up. I replaced it and today have ridden it. So far so good.
 
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FYI I also replaced my battery today. I tested it and found it bad. The bike would barely run, showing like 5v across the batter terminals with a DMM. I was told by a Kawi dealer that 12is is good when off. Start up running at idle should be 13ish and 4-5000 rpms should be about 14ish. I had been having problems with it just suddenly dying and not being able to get it to crank again. I have pushing it off b/c of the starter clutch issue but the battery problem, which was diagnosed after the starter clutch problem was fixed, and the starter clutch both forced the starter clutch repair. Jesus was really kind to me here.
 
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Starter Clutch/Stater configuration

I did a starter clutch repair this past week. I wished Id took pics. But Basically. THe starter is continuously connected to an idler gear and that is connected to the starter clutch gear which also is apart of the harmonic balancing system. The starter clutch has little round cams which lock when you want to starter but are free spinning whilst running. If these go bad get out of shape as mine did. Then you'll have free spinning starter problem and will be doing alot of pushing. LOL:doh: to get it too start. My son is a tough kid. He really helped me alot with this. (9 years old) the Best source of info is a kind kawi tech and a service manual. Here is the link http://www.tocmanufacturing.com/File...nd Parts.pdf. Sec 8 which is engine look through till you see the part about crankcase. There are some decent diagrams that I found very helpful. Also the rest of what is needed is found in the electrical/ section 15 under the starter subsection. This has probably the most pics and information. You should drain the coolant. Then the oil. The bottom frame section along with the foot rest assembly needs to be set to the side. The frame piece requires an 8mm allen bit/socket. They were really tight. You can torque the plates back down to about 15ftlbs and the Starter clutch gear is rated at 51ft/lbs. I used an impact wrench but probably should have used a regular wrench and then a torque wrench. The starter clutch gear will not stay still so I put a penny in between the idler gear and the starter clutch gear. That worked good. Be sure you used some blue thread locker. I found a 1.99 bottle at harbor freight. Feel free to email me if you have any questions about this repair. I am so thankful I got r done.
 

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wickedwhip21
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25 Posts
Discussion Starter #13
Alright, I got fed up with the guessing and pulled the engine. When I bought the bike it wasn't running because the guy began dismantling to replace a bad stator supposively. When i got it home, I found that the negative lead on the battery was hanging on by a few threads. Replaced that, put in new oil, fired her up. Then there was tapping, which turned out to be dampeners. Pulled the engine, replaced those, now these issues. I have began tearing down the engine, I found that the clutch was put together incorrectly by previous owner. Friction rings were set next to eachother. There was no Steel ring in between. Clutch was toast. I figured while I had the engine out, I would tear down to the block and see if there was anything else I saw. I removed the cylinders and pistons, and I found play in the connecting rod on the crankshaft. Time to build from the ground up!!!:drool:
 

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wickedwhip21
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25 Posts
Discussion Starter #14
Found the problem!!

Well, I have tore down the engine completely, and am sickened by what I have found. Rods, Collars, and Crank Shaft are shot. :doh: Not sure what exactly happened. Maybe put back together incorrectly before. One of the rods had no collars, and the set of collars for the other rod were ate up. Source of metal shavings I presume. I am glad I decided to tear it all the way down. Check out the pics. Anyone have a crankshaft and connecting rods for sale? :drool:
 

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Patriot Guard Rider
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825 Posts
That's too bad that you live so damn far. I have motor sitting here but I've never cracked and engine open in my life.
 

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Linkmeister Supreme
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Well, I have tore down the engine completely, and am sickened by what I have found. Rods, Collars, and Crank Shaft are shot. :doh: Not sure what exactly happened. Maybe put back together incorrectly before. One of the rods had no collars, and the set of collars for the other rod were ate up. Source of metal shavings I presume. I am glad I decided to tear it all the way down. Check out the pics. Anyone have a crankshaft and connecting rods for sale? :drool:
That is a sorry sight alright. Looks like the PO shouldn`t have been allowed to handle any wrenches. :(

BTW, the piece in the 3rd picture, what you are calling a "collar", is properly called a plain bearing. :)
(Plain as in having no rollers or balls, just accurately machined metal surfaces.)
http://en.wikipedia.org/wiki/Plain_bearing
 

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wickedwhip21
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25 Posts
Discussion Starter #17
Thanks Ol Hoss on proper part name. I hadn't looked the part up yet. I was deeply sickened when I saw this. I was just hoping the rod play on the crankshaft was going to be an easy fix. With that rod being loose on the Cranshaft, it caused it to wear into it. I have a buddy that works in a machince shop. I am going to see if there is a way to save it. I doubt it, but worth a shot. If you hear of anyone having some rods and a crank shaft laying around, please let me know. I was hoping this was going to be a simple project with an easy fix, but not so lucky.:doh: What can you do though. I am glad I just decided to tear it all the way down now. I can get it built right! Quick question, could I put the VN750 cylinders into the VN700 block? I am thinking while I have it dismantled, if possible, I should do it. I have seen several cylinders on ebay for sale. I even found a set for $100 already loaded with pistons. Thanks for all of the help!! Much appreciated!:smiley_th
 

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Old Truck Junkie
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4,133 Posts
If you change cylinders you have also change pistons and rings. But I hear that it does work.
 

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Linkmeister Supreme
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Quick question, could I put the VN750 cylinders into the VN700 block? I am thinking while I have it dismantled, if possible, I should do it. I have seen several cylinders on ebay for sale. I even found a set for $100 already loaded with pistons. Thanks for all of the help!! Much appreciated!
If you change cylinders you have also change pistons and rings. But I hear that it does work.
niterider is correct. The 750 cylinders will fit the vn700 crankcase, and you need the larger diameter 750 pistons to fit them.

For help with the rebuild see Roach`s videos:
http://www.vn750.com/forum/showthread.php?t=18289
 
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