VF400F(D) C-Reg

[Hugh]

Hi all,

First off, the bike has not been running since 1995 ... 3 things, if I block off the vacuum pipe inlet on no.1 cylinder and remove the diaphragm spring on the tank tap will it get enough fuel flow? And on the rear 2 carbs the balance pipe is a T section and has a rubber hose attached, but where does the other end of the hose attach? (I don't have a manual and cannot seem to find one for this model, not sure if the vfrÅ› are the same?). The starter motor spins fine for 2 or 3 turns and slows and stops but is taking massive amounts of power almost like it is shorting and battery leads glow red! ... Any help much appreciated.

[Cammo]

Sort the easy stuff first!

First up would be to get the starting system working properly. Glowing leads sounds like a big short circuit, check all battery leads, and other earths, etc. The wiring will be similar to an NC30, best to get hold of a wiring diagram.

Make sure the battery is good, and that the motor is willing to turn (i.e. not half siezed!). Jack up the bike, put it in gear and turn the wheel to make sure the motor is spinning freely.

[nc21man]

I'm assuming this is an NC21. Firstly, why do you want to remove the diaphragm from the fuel tap - unless it's split, leave it alone otherwise too much fuel will get through and flood it. Secondly, I'm pretty sure the rubber pipe is just a breather, though I could be wrong, I can't remember exactly what mine looks like and I'm not going outside to look as it's p***ing down! (if I remember, I'll look in the morning and post tomorrow night). Thirdly, do as Stickshift says regarding the electrics cos they aren't my strong point Finally, if you have got an NC21, you won't find a manual for it (or an NC24 for that matter) - Haynes do a manual for the NC30 and there is a section in it, I think, for NC21 & 24 specs and torque settings. Lots of the cycle parts, engine parts and wiring are similar, so it is a useful aid if not exactly a bible.

[Hugh]

Cheers both, I'll get the wiring looked at and take the starter motor apart as I'm sure it just needs some tlc. As for the fuel tap mod, the brass pipe that the vacuum pipe connects too has been sheared off, hence wondering about a work around .... Also will be taking the carbs off to clean out any gunk inside them.

Where is the fuse for the neutral switch/light?

[Hugh]

It's even older, an NC13 and diagrams and info are impossible to find

Just spent 2 days cleaning out the carbs, they were thick with green muck ... then I managed to break the part where the 2 cables attach so am now seeking some new carbs. Did you manage to look under your tank for me nc21man?

[el_dudino]

I was in Alford in Lincolnshire at the weekend and saw a proper Honda manual for one of these in an antique shop!!! I didn't look at the price but I assume by the price of all the other stuff in there it'd be around a tenner. Maybe someone local could pick it up for you?!

I've got a VF500 which is essentially similar, but without the enclosed disc brakes and has a square-section frame rather than the round tubing on the NC13. Mine's still waiting full restoration after about 4 years of ownership!

[Hugh]

Cheers el_dudino, I just bought an original Honda one for an extortionate amount off eBay. Wishing you better luck with your VF500 than I am having with this 400.

Looks like the starter motor is a dead short to earth so thats next on my list for a strip down and clean ... lets see if i can break that too ... lol :)

[fastdruid]

I've got a 84-85 VF500C microfiche/parts book pdf if it's any use, tragically the site I downloaded it from seems to have gone awol otherwise I'd just post the link.

PM me wih an email address if you want a copy, it's 10Mb so make sure your mailbox can cope!

Druid