these arrived today, all the way from France…
Interesting reading. Do you think they would remember what they did for you or would it be best to take my pipe work along to them. I take it the adapters have a different bore too.
I dont think they will remember what they did regarding my pipework, so it may be best to take yours in if you decide to go with bigger pipes,
But before you do, there’s a few things to consider, there are plenty of vf1000ff and f2f that are running around perfectly happy with the -2 standard pipes, same as crooky supplies with his kits…
For the moment, i have taken the bigger pipes off and gone back to the -2’s, as some of my thoughts on this may be wrong, i still believe the standard original rigid pipework supplies more oil to the heads, but may not supply it equally between both the heads as the -2’s do.
My concerns are that the larger -4 pipes i had made up supplies too much oil to the heads and could potentially rob oil from the main and con rod bearings which are now virtually obsolete…
I will hold fire for now.
The new oil feed is also at higher pressure, so that may also compensate somewhat.
Just had a look at the Doughety kit I have and that is AN-4, but is a single feed split in two.
The paperwork with the kit I have fitted says AN-3, but they look like AN-2.
yes, that looks like a -2 banjo bolt, which is way smaller than the banjo bolts used on the original rigid oil line,
The original experiment i did with the original rigid oil line fitted and the two -2 lines and spin on adapter in place at the same time was flawed, it stands to reason that more oil would be pushed through the larger pipework than the smaller while both circuits were open at the same time.
My thoughts now are that the -2 lines actually increase oil pressure throughout the system but possibly deliver slightly less oil to the top ends… It’s really a bit of a balancing act, if you increase the the amount of oil to the top end by fitting bigger hoses you will decrease the amount of oil and pressure to the crank.
I’ve followed the ups and downs of the oil feed to the cylinder heads with interest and decided to do a bit of research on the subject.
It’s a commonly held thought that the standard feed pipe supplies unfiltered oil at a lower pressure than the main gallery.
This is true,the oil is unfiltered but at pump pressure until it reaches the banjo bolt at the bottom of the oil line.
The bolt has a 4mm diameter vertical drilling allowing oil to feed through two 4mm holes into the banjo.
This restriction in a 7mm internal supply line reduces the pressure from this point on(the standard oil line has a larger diameter than the banjo bolt so the pressure drops)To give you an idea the difference that makes consider the area of the oil ways
7mm=38.53mm square and 4mm=12.58mm square.
Honda did think about keeping the supply equal front and back,and to compensate for the rear pipe being shorter than the front made the rear banjo smaller internally than the front.
At the head the banjo bolt has a triangular restriction that fits inside the banjo that seems to offer no restriction at all,the available area for oil between the two is a whopping 30.5mm square.(2.5 times the supply area each)
Simply opening the vertical drilling out to 5mm would increase available oil by 56%
-2 has an internal area of around 3.14mm,so even two lines don’t supply as much oil as the standard setup.
Pressure is maintained in the whole system by the bypass valve,it spends most of its life open to a greater or lesser extent depending on oil temperature and engine speed,I doubt that fitting -4 pipes would exceed its ability to maintain pressure.
Sorry if this tome is a bit boring I’ve now taken my anorak off,regards Bif
A further thought along the oil supply line,Honda have used the same banjo bolts top and bottom on the F/RE and F/RF and G they did however change the oil line when going over to the line bored heads.
I will fish an early oil line out from the store tomorrow and see what changes have been made.
At a guess I’m thinking restriction on the rear head banjo.
WRONG,I can see no difference between the two.
Had a long talk with vf Pete about this on Saturday,I think we both came away with more questions than answers on the subject but also a couple of ideas to increase oil flow in general ergo pressure too.
Finally managed to ride the vf today, just a short journey to the mot station and back, it handles really well on the new tyres and rear shock, theres still a few things to finish off but will do them as i go,
It looks very well Pete,is the rear end lifted a bit?
I only hope the Bol turns out as well
Wow!, that looks great Pete!
The bike looks very good Pete all that hard work looks to have paid off, will you be riding that one to Hulme ?
Nice is that Pete.
Very nice bike, Pete!
thanks for the comments, yes i’m fairly happy with how it has turned out, to be honest im glad to see it all in one piece, it has not been an easy build, the amount of things that has gone wrong is unbelievable, its been a case of “what can go wrong, will go wrong” even my choice of tyre’s turned out to be wrong, I originally put a 160/60zr17 Dunlop sportsmax qualifier on the rear, great tyre, unfortunately it measured 170mm which only left a 1mm gap between chain and tyre, so had to change that for an Avon 3D ultra sport which measures 162mm.
Bif, im not sure about the height of the rear, it feels higher but it is still 815mm to seat, I left the rear shock at the height that wilbers set it at 410mm, but the tyre is a lower profile, using the fe swingarm and linkage on the ff frame may have altered the geometry a little, however it has happened it feels just right. the front end is probably a little lower too having the 17 inch front on…
Paul, assuming it turns out to be mechanically sound it will be my main ride, so hopefully it will be chugging its way to hulme end…
The FF shock is 10 mm longer than the FE one,so assuming you used all FE suspension components the rear will be higher,but the 17" front wheel will drop the front end by 18mm so the seat height will be about standard.
The bike has a great stance and should be a bit of a giggle in the twistys,roll on Hulme End or maybe Scotland?
Looks fantastic Pete, thanks for the pics.
Looks wonderful Pete, a credit to you. If I may be ultra critical ? Not sure about the brown brake callipers.
Bif, I want to see this bike in the flesh so lets get some Scotland dates put together ? Probably need to be before Hulme End wont it ?