Kawasaki VN750 Forum banner

1 - 20 of 77 Posts

·
Registered
Joined
·
60 Posts
Discussion Starter #1 (Edited)
Hey guys,
Just bought a 92 VN750 20k miles. Actually my friend did but I'm his mechanic so it makes more sense for me to post questions. Bought it from a guy who said he taught his wife how to ride on it. He had 2 Harleys worth about $20k each so it made sense to me. So far just went through the usual. Changed the oil which seemed new but very thin. It has a slight oil leak on the left side so no synthetic for this bike. Rotella triple T will work just fine. Pulled the oil screen out (nice feature) only had a few specs of metal in it. Changed the final drive oil which looked like it had never been changed. Pulled the(claimed to be new) 10 year old tires off (he had his wife on 10yo tires!?!) and put some Pirellis on. Couldn't find much for a radial so bias ply it is. And really? I have to take the muffler off to change the rear tire? Changed the spark plugs which was a mix of dpr8's and 7's. Plugs looked pretty good. Rear cylinder is a touch lean but I don't see where the pilot screws are. I don't have time to rebuild the carbs right now so its getting an Italian tune up with a can of seafoam. The guy we bought it from said it needed the valves adjusted. I'm thinking these are hydraulic lifters and it sounds more like cam chain slap to me. Not bad and I'm starting to lean towards that this is just the way the bike sounds. I see 2 chain adjusters that look like the automatic kind. 1 adjuster for 2 chains? If its DOHC then thats 2 cam chains per cylinder. A little bit of drag on the front brakes but I don't have time right now to rebuild them either so I just crunched the piston in and pushed it out a bunch of times and that helped. I took the bike on a 20 mile test ride and its not bad. Reasonable power, handling, comfort. I grew up on dirt bikes so I don't really like forward controls but it wasn't bad. Either way it fits my friends style of riding perfectly.
 

·
Registered
Joined
·
60 Posts
Discussion Starter #2
I was on the other Vulcan forum and got some of the answers to my questions. It is 1 tensioner for 2 cam chains. I'm going to try the "Grambo trick" and if it doesn't work I'll go with manual tensioners. I'm still not clear on the pilot screw location. I was told "The air adjust screws (pilot)are capped off at the factory.need a small punch or nail to put a hole in the plug and pull them out" Is it capped with foil or something? I'm assuming I'll find what you normally find when you pull the limiter cap off? I do have a color tune which this bike shouldn't mind since theres 2 plugs per cylinder. Theres 2 oil leaks. 1 is on the right front cylinder that I'm hoping is the valve cover gasket. Oil is collecting in the spark plug hole but I'm also seeing oil on the head gasket. I'm hoping its not the actual head gasket and its coming from above. The 2nd oil leak is on the left side and the oil is collecting on the frame. When I get a chance I'll give it a really good cleaning and spray it with foot powder and hopefully see where its coming from. I usually work on older bikes so chasing oil leaks is something I'm use to. The petcock also leaks fuel when you spin it but I already looked at a parts diagram and it looks like its either an o-ring or a gasket which are both $1 each so I'll just replace both of them and be done with it. I should probably also hook my carbtune up and do a vacuum sync. Are the sync ports on the manifold boots?
 

·
1986 VN750
Joined
·
3,255 Posts
"Chain Slap" is just the automatic cam chain tensioners. Buy some manual ones and you'll never have to worry abou tit again. TOC makes a great set. Sure you can convert yours, but I trust the TOCs much more.

I swapped my bars out as I can't stand the mini apes that come with the bike. Used these and a clutch cable off an early KZ1000. https://www.denniskirk.com/599831.sku

Pilot screws are on the carbs, they're usually hidden with a little chrome plastic cap. Remove the cap to gain access.

Carb sync ports are the 2 vacuum ports on the carbs. One per side. One is connected to your petcock, the other to the emissions junk unless it was removed/capped off.
 

·
FREEBIRDS MC CENTRAL NY
Joined
·
16,197 Posts
Look on your newbie post I have a few links for making mcct's
 

·
FREEBIRDS MC CENTRAL NY
Joined
·
16,197 Posts
The plugs for the air adjust are just thin metal plugs.I'll take a pic when I get time.
 

·
FREEBIRDS MC CENTRAL NY
Joined
·
16,197 Posts

·
1986 VN750
Joined
·
3,255 Posts
You can edit your post so you don't have 3 replies Doc ;)
 

·
Registered
Joined
·
60 Posts
Discussion Starter #8
"Chain Slap" is just the automatic cam chain tensioners. Buy some manual ones and you'll never have to worry abou tit again. TOC makes a great set. Sure you can convert yours, but I trust the TOCs much more.

Pilot screws are on the carbs, they're usually hidden with a little chrome plastic cap. Remove the cap to gain access.

Carb sync ports are the 2 vacuum ports on the carbs. One per side. One is connected to your petcock, the other to the emissions junk unless it was removed/capped off.

"Chain Slap" is when either the tensioner is not providing enough tension or the cam chain has stretched beyond the limits of the tensioner. I had an SV650 that the chain had stretched too far. The amount of racket that bike made is no where near what this bike sounds like. I was going to try the grambo 1st since my friend is on a very tight budget. Last season he destroyed the engine on his old bike by riding it around with about 1qt of oil. He had just got done sinking a lot of money into it to get it right. Which is also telling about his lacking mechanical skills.

So it is a vacuum actuated petcock. Thats good, I can just follow the hose off the petcock and look for something similar on the other side.
 

·
Registered
Joined
·
60 Posts
Discussion Starter #9
Thanks ODD. I'll look for that hole when I have the bike again. I'll also look for the pilots. It really just needs 1/4 turn on the rear cylinder. Are the pilots in the typical location somewhere around float bowl?
 

·
Registered
Joined
·
8,200 Posts

·
Registered
Joined
·
60 Posts
Discussion Starter #11
Oh, thats awesome. Its usually such a pita getting to those screws on a running bike without burning yourself. If only Honda and Suzuki would put them in that location. I know guys that have taken the idle knob of Kawasakis and put them on Hondas because thats also a pita to get to.
 

·
FREEBIRDS MC CENTRAL NY
Joined
·
16,197 Posts
You can edit your post so you don't have 3 replies Doc ;)
Probably but it's easier for me to do it like this. And I'm a post count whore.I'm trying for the highest post count;)
 

·
FREEBIRDS MC CENTRAL NY
Joined
·
16,197 Posts
Hell this is post 11128.
 

·
FREEBIRDS MC CENTRAL NY
Joined
·
16,197 Posts
11129
 

·
FREEBIRDS MC CENTRAL NY
Joined
·
16,197 Posts
11130
 
  • Like
Reactions: One1

·
FREEBIRDS MC CENTRAL NY
Joined
·
16,197 Posts

·
Registered
Joined
·
60 Posts
Discussion Starter #17
I'm back. Went over to my friends place because he was having trouble getting it started. I was able to get it to fire but it wouldn't idle. Drop below 3k rpms and it would die. Eventually we drained the battery too much and could only bump start it. It was an orchestra riding it back to my house. My friend wasn't able to do it so he rode my bike and I rode his. Pull in the clutch but don't let go of the throttle, use the rear brake to slow down, idle at 4k at every stop light. When I got to my driveway I just let go of the throttle and it died. Was definitely warm enough, the cooling fan was on. Might be that the battery was too dead to idle but I was able to get it to fire off the battery once in the beginning. I'll have to look at the charging system but 1st I pulled the carbs. By far the most difficult carbs I ever pulled. Taking them apart you could either call the design clever or overly complicated. Not sure if it is the problem, clogged pilot or slow jet, but either way it surely needed it. Threw them in my ultra sonic cleaner with pine sol. It needs new float bowl and jet cover? gaskets. Kawasaki wants stupid money for a float bowl gasket but I'm not finding any after market. $10 for a $2 o-ring gasket. Also its having a problem with sometimes if you hit the start button nothing happens. I initially thought it was the solenoid but after messing with it, it seems that it maybe in the ignition. If I rocked the key back and forth I could get it to crank. Sometimes the neutral light wasn't even on because it was in between off and on but it would crank. I do remember shooting it with contact cleaner and renew & lube. Might have to take that apart as well.
 

·
Registered
Joined
·
292 Posts

·
Registered
Joined
·
60 Posts
Discussion Starter #19
So I took the ignition "puck" off. That was fun, someone had been in there before and broke the little tabs holding it together. As I was taking it off the bike it started to come apart in my hands. Was scared for a second when the pieces just started falling out. I didn't lose any and when I got it on my bench it seemed self explanatory where everything went. At least I hope so as I can't really test it with no carbs on the bike. The contacts were dirty but looked like they should still conduct. Might of been that the puck was separating. Either way I cleaned everything up and used a dab of super glue where the tabs use to be. Hopefully I don't need to open it up again.
 

·
Registered
Joined
·
60 Posts
Discussion Starter #20
Wow, thanks for the tip about the greasing the splines. I pulled the final drive off and a giant rust cloud came out. I've never seen one this bad even on bikes much older. I cleaned it up as best I could. The teeth are pretty jacked up but I have no time or budget to replace it so it got packed to the brim with moly grease.
 

Attachments

1 - 20 of 77 Posts
Top