VF1000F rebuild - Carby & Spark unit questions

Hi Everyone,
I’ve just signed up to the forums but have been reading up for a little while now.
A couple of months ago I bought a VF1000F, it was in fairly shabby condition, but underneath all the muck I thought I could see a nice bike lurking.[:)]
I have a couple of questions about carbies and spark units but I will give you a bit of history on the bike first.
When I first spoke to the seller he told me the bike had been sitting a couple of years before he bought it, he had then had all the hydraulics fixed up to get it running again, he had it for about 12months when the starter packed up, he managed to get a rebuilt unit for a couple of hundred dollars and fitted this, after another six months the rego ran out and he had it sitting for about 2 months,he went to start it and the battery was shagged, so more money for a battery. He then ran the bike (idling) every couple of weeks while he decided what to do with it, in the end putting it up for sale.
He told me that it had been running fine when he first parked it but was now staring to miss on no2 cyl and wouldn’t idle properly without a lot of choke.
When I first looked at the bike he had cleaned the no2 cyl plug and had it running on four again. It started quite well ( was cold)and sounded quite good, no rattling or knocking etc, but
wouldn’t idle even when warm,just coughing and spluttering, the engine would die if the choke was off and you let the revs drop.
I went for a ride, it seemed sluggish on takeoff but once around 2000rpm started pulling away ok, first and second gear were fine but no room to wind it out any further, seemed to rev ok with no misses or odd noises.
So I thought the carbies are gunked up, 6 month old fuel ( with a couple of top ups of fresh he said)seemed like the pilot circuits may have been blocked on a couple of carbs ( It was too late by this point as I had taken a liking to the bike and that was that![:D]

When I got it home I went for another ride with similar results, in the end it conked out and didn’t want to start again, so I thought “into the shed for you” and I started stripping her down.
What I have found so far;

1)Air filter is clogged with muck
2)Fuel filter also full of muck and fine pieces of rust/dirt etc
3)Carbies full of dirt/muck, needles all gunked up, diaphragms stretched with NO1 having a small hole and NO2 cyl carb slide had been replaced at some point with a plastic slide, about half the weight of the originals, so I couldn’t see that working properly.
4)Compression check (cold) gave me 165psi on all four cyls.

I have since removed the heads as I could see one of the exhaust valves in NO1 cyl was oily looking (the other was ok)probably valve stem seals needed replacing.

Cams were good and still in spec although 3 of the rocker arms had small chips out and had marked the cam lobes slightly, I will replace the rocker arms and have been advised that a light polish with wet & dry should blend the slight mark out of the cam lobes affected. Chain and tensioners all look good.

Yesterday I split the engine case as the two rear cylinders had a light stain, probably from a head gasket leaking and the coolant sitting for a bit. I intend to hone them all and replace the rings and maybe main bearings although it looks very much like the engine was rebuilt not too long ago as everything looks to be in very good condition,clutch etc all good. I still have to measure all cyls rings etc to see how they shape up (will call in a favour from a mechanic friend for that)

So after that long winded story I’ll get to my questions!

I was wondering if any of the idling problem sounds like it could be related to a failing spark unit? I did notice the tacho jumping a bit when it tried to idle (if you could call it that!)but once the revs were up a bit it was fine
I will be getting four Keyster carby kits and also having the diaphragms replaced when I eventually find the correct slide for it, so hopefully this will sort out the carby, but I have this nagging feeling that maybe there’s something else going on?

Thanks in advance for any help
In sunny dry dry South Australia

Hi Tony, i live in sunny dry Qld, the odd slide / diaphram would be a definite problem, i once had a crook spark unit, it didn’t play around it just died completely, can you tell me where you are getting your parts from, i am having trouble getting them I have a jumping out of fifth gear problem probably broken dogs on the gear so my motor is out at the moment plus a small oil leak from between the casings at the rear of the engine dripping on the exhaust collector. I will pull it down over the next week after work etc… and will be searching for parts by the weekend, finding that some parts in the past have been impossible to get, will be making my own extractor system soon too, my pipes are quite burned out.

Hi Ray,
Thanks for the info, I have been getting most parts from Service Honda in the US,
They have an online parts list and had 95% of the bits and pieces I asked for, shipping is a bit expensive but at least I had what I needed.
I asked at the local Honda shop for a price on a top end gasket kit just last week and he quoted me $350Aust for it! It is still cheaper to get one from the US, I also spotted a full gasket kit here;
That seems the best so far.
and also David Silver Spares in the UK,
They have a pretty good range, some cheaper than service Honda and some more expensive.
The carby kits and diaphragms come from NRP Motorcycle carburettor specialist in the UK
You need to send your slides to him and he will fit and then return them, about $70 each with postage both ways.
The Kits are about $40 each with pretty much everything in them.
I have been emailing wreckers for odd bits and pieces,
Show and Go in Adelaide have a few bits and pieces;

Hope that helps

Looks like I may have found the problem, I have started stripping the carbys and found all four of the slow jets were blocked, two completely and two 90%.
One of the float valves was seized and no3 carby sync adjustment was seized up.
The butterfly for this carby was in quite a different position to the other three so would be way out of sync.
Add that to the diaphragm hole in one and the dodgy plastic slide in another…quite amazing it ran at all!

Hi Tony & Ray,

I have quite a few spares and have a good knowledge of where to find spares in Australia as I have been at it for quite a few years now.
If your interested or need anything drop me an eMail: paulf1961@hotmail.com
I have spare motors, exhausts systems carby parts etc. As well as a very good understanding how to rebuild and race VF1000Fs.


Thanks Paul, very nice to know!

that is nice paul, i think i’ll email you… Ray.

Having trouble finding aftermarket spares in OZ , will email u . . … Cheers Ron