1983 VF750F - Starting Problems

Hi all, I'm new to the forum, and new to the VF750f. I picked this one up only a couple of days ago for £1000 (about $1600).
It's only got 21,000 on the clock, and someone has obviously spent some money, and effort, getting it in to it's current condition.



The cam chain tensioners were replaced before I picked it up, and the only known fault on the bike was the fuel gauge.

I know the bike has only done about 100 miles in the last 5 years because I've got some of the MOT's and service reciepts for it.

Everything was running fine for the first two days until I parked it up at work yesterday, and when i came to ride it home... it was a non-runner.
Ended up with a 45-foot tow truck carrying it the 1 mile from work to my house.

When you press the ignition there's a smooth electrical sound as though the starter motor is spinning nicely, but it was like the engine just wasn't connected to it.

Read somewhere on the net about a technique of putting it in 3rd or 4th gear, rocking it back and forth a bit, and then starting it.
Believe it or not, this actually worked (with a jump start from my car battery because I'd flattened the bikes battery trying to get it going).

The bike is running again now, but it still seems to do the whirring thing before it will crank occasionally.

Any suggestions on what this is likely to be?

Everything seems fine now, but I don't want to be causing any additional damage.
If it was the starter motor or a solenoid, or something electrical like that, surely the 3rd gear 'trick' wouldn't have made any difference. So I'm thinking mechanical.

 

Starter clutch

 

Is that a guess, or a "yep... heard it a thousand times"?

 

A thousand times.......maybe more.

 

Well thanks for the quick responses guys.
Guess I'll have to look at replacing the starter clutch (or fixing the springs in it... been googling the problem).

Doesn't seem like a nightmare job, and relatively cheap.

And at least it's running for now.

 

The "mostly likely culprit". When the temps get cooler the problem gets worse.

 

Rebuild kits are available through Honda or other sources such as the v4market.com. Ower's name is Brian. Super guy. Just talkd to him on the phone about some parts for an 2nd gen Gold Wing. He may have them or can find them. Tell him that idiot Jeff in Franklin, Tn sent you.
He is in the New York City area.

 

Starter clutch springs are cheap and easy to replace, cracked housing isn't.

 

My '86 750 has done it a couple of times since the cold weather set in. It catches 2nd try. No problems restarting when the engine has warmed things up. It's probably just telling me that it doesn't want to start...it's not a snowmobile engine.

On my list of fairly simple things to do since it will not get any better by itself.

If it was a car I'd just smack it with an orange dead blow hammer but the bike gets more respect.

 

Looks like the problem has sorted itself for now at least. I've never had the same whirring sound when it's starting since I got it back on the road. But I haven't touched the starter clutch (yet).

I found my battery was wrong too. It seems like something old that the previous owner had just shoved in to get it running.
It was only 7ah (instead of the recommended 14ah) and seemed to be on it's last legs.

I've switched it for a new one of the right size. Just one other queston for you experts though. On the same issue:

I've heard that the reg/rec is a common fault, which might have been the death of my previous battery, hence the problem.
But from what I've read the Reg/Rec faults are mainly 2nd and 3rd Generation issues. (Mine is a 1st Gen VF750).

Is the 1st generation commonly afflicted by the dreaded Reg/rec issues too?

 

Give yourself a few pats on the back for replacing the battery with the CORRECT one. That in itself has probably fixed some other issues that didn't come to light just yet.
As for the starter clutch...if you're having "slipage" in the summer it gets worse in cold temps.
All regulators/rectifiers eventually go bad. The main problem with the charging systems from the 1st generations and on up into the late 90's (4th gens) was/is the 3 yellow wire connector...it gets hot enough to slowly burn itself up. Then you have charging issues or you are broke down. On the 1st gens (including the Magnas Sabres and Shadows) most just simply cut out the burnt wires until you have good clean wires then SOLDER in longer wires (makes it easier to get the battery in and out) SHRINK WRAP the wires and be done with it. Be sure to slip the shrink wrap on before you solder. Yep been there done that.
To help that 3 yellow wire connector to last is to keep those contacts CLEAN. (your wife's/girlfriend's finger nail file cut to fit works pretty good) And also use electrical contact cleaner. Even disconnecting and reconnecting a few times help keeps a good conductive connection. Dirty contacts create heat. Heat causes more resistance then more corrision and then creates dirty contacts. See the pattern here? ALSO running a battery with a weak or almost dead cell makes the reg/rec go into overdrive because it's thinks the battery is not charged enough....creating more heat in those 3 yellow wires.
Someday I hope to find an 83 VF750F I can make a project bike out of......just gotta be patient.
Jeffrey

 

Photos of that plug mentioned above.......



If and when the melting causes any 2 wires in there to touch, it blows the stator immediately.

 

Thanks all. I've checked the cables in question and can't see any obvious burn / wear on them, so all looks good there.
Since replacing the battery it starts first time every time, and it's been about -2 in the mornings here recently, so it looks like those worries are over.