1994 Vmax dying under load

[Thestrugglebike]

Hi. I’ve been reading these thread for a while. I got a new to me Vmax 1994 and have been trying to get it up and running properly. I have cleaned and synchronized the carburetor, got a new battery, put new spark plugs in, and put a new fuel filter on. At this point the bike will idle and rev in neutral but when releasing the clutch in gear the bike bogs down and dies. I’m looking for a direction to figure out where to search next.

 

[MaxMidnight]

Has the bike always had this problem under your ownership or did it start after you 'fixed' it?
Are the plugs showing signs of a weak or rich mixture?
Are all of the throttle slides lifting in concert?

 

[Fire-medic]

Put it on the centerstand, get it in 5th gear, with the sparkplugs out, and try to turn the engine over by hand with the rear wheel. If you can do that OK, then I think I'd try a compression test and a leak-down test.

Something else you might try is to remove the clutch cover, and see that the clutch plates are able to be separated. Pull in the lever, fasten it down, and try to get the plates apart. You should be able to use a screwdriver to easily pry-apart the tabs of the friction discs in the clutch basket. If they're stuck-together, remove the pressure plate, the diaphragm spring, and all the friction discs, and the 'steelies,' use some sandpaper to roughen the 'steelies,' and throw the friction discs into a shallow pan with fresh oil, and oil them good. Let them soak in the oil for awhile, and reassemble. You'll probably need a new clutch cover gasket.

Sometimes bikes sitting for extended periods have the clutch plates stick together.

 

[sdt354]

Kick stand switch?

 

[MaxMidnight]

Assuming that when Mr Thestrugglebike says 'the bogs down and dies' he means the revs drop and the motor stops rather than a sudden cut out e.g. you flick the kill switch then I wouldn't be looking at either the clutch or side stand interlocks.
Nor would I be looking at the clutch pack as you would expect the bike to jump forward before it died.

It would be helpful if he could elaborate further on how the motor cuts out?

 

[Thestrugglebike]

The bike will start great, idle great and rev in neutral. I can pull in the clutch and switch to first gear and be fine. As I’m letting out the clutch and giving gas the bike rpm’s stumble hard and it dies unless I pull the clutch back in. I’ve made it down the street and it died and I eventually made it back. I started from scratch here as I bought it as a project. It was last tagged in 2009. Originally the bike would only start with choke and die after warming up before the carb clean and rebuild. Now it idles perfectly fine and revs. Everything appears to be stock. I will dig into it more based on your suggestions when it’s not over 100f.

 

[Fire-medic]

OK, a weird one but what could be happening is the star selector on the shift drum has come-apart. You think it's in 1st, but it's in a higher gear to start. I dunno if that's it, I kinda doubt it, but it could be. Think of trying to start out in 3rd or 4th on a manual transmission C10 truck, you're only gonna get underway slipping the clutch a lot.

Can you get it into 1st gear OK, and then toe it through each gear until 5th? Engine running & engine not running. If you can easily 'catch' each gear going up/down, then it's not the star segment & its pins on the shift drum.

 

[Thestrugglebike]

I’ll do compression checks when I get a chance. It is stumping me. I can shift through the gears fine. Maybe some type of binding when in gear with the clutch out? I do a little wrenching here and there but most in-depth stuff is a learning experience.