FFTS
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| posted on 24/3/10 at 10:39 AM |
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Informed opinions on Honda Blackbird engines in 7's
Standard Blackbird engine in an Indy. How would it compare with my standard ZX9R ST. I guess the Blackbird is about 160bhp compared to around 130 for
the ZX9R.
All knowledge imparted gratefully received, especially if you have one, had one and have compared to other (Blades/R1's etc)
P.S. Hope my new Avatar aint to sexy for you all.
Chris.
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Brommers
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| posted on 24/3/10 at 10:55 AM |
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I have a 'bird-powered Fury, which I crashed in 2003 and am still rebuilding, and a Striker with a ZX9R engine. The 'bird is a great
engine for a road car - it's certainly got the edge on the ZX9R for power, and the gearbox is much stronger. For a race car it's blown
away by the modern 1-litre engines or the ZX12R, but for a road car and track car it has a lot to commend it.
The only problem with the 'bird engines is that as soon as the oil pressure drops they blow up - usually the no. 3 mains pick up and they
detonate. If you dry sump them, they're fine. It is possible to keep one running with a wet sump, but I've tried it before, and
I'm not trying it again - that's how engine number 1 died...
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FFTS
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| posted on 24/3/10 at 02:19 PM |
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Whats the "no 3 mains pickup"?
So if I could buy a seven with a Blackbird in it for road driving would it last as it is. I like to drive fast but country lane stuff.
What is it that makes a powerful engine like the blackbird good on the road but outclassed by a 900+cc engine on a track?
What would be the difference I would notice when driving?
Chris.
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Brommers
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| posted on 24/3/10 at 02:32 PM |
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quote:
Originally posted by FFTS
Whats the "no 3 mains pickup"?
What I meant was that when the oil pressure drops, what usually happens is that the oil supply to the main bearing on the conrod on cylinder number 3
is reduced, because that oil feed is shared with the balance shaft. Due to a lack of oil pressure, the bearing hits the crankshaft, the crankshaft
picks up bits of the bearing onto its surface through friction, and this rapidly escalates into the bearing failing and the conrod being blown
apart.
quote:
So if I could buy a seven with a Blackbird in it for road driving would it last as it is. I like to drive fast but country lane
stuff.
If it has a dry sump and you keep the oil level correct, then yes. It is has a wet sump, probably OK for road use but not for track work.
quote:
What is it that makes a powerful engine like the blackbird good on the road but outclassed by a 900+cc engine on a track?
Weight, mostly, and power. Modern litre bike engines, like the 2006 R1 I've got in my racecar (in the avatar) produce 170-175bhp, but weigh
about 15-20kgs less than a bird engine. That sort of difference makes a difference on a track, but no real difference on the road.
quote:
What would be the difference I would notice when driving?
Compared to a ZX9R? Not a great deal really, I'd imagine. The engine would run more smoothly (the 'bird was designed to be rigid-mounted
to the bike frame, the ZX9R wasn't IIRC), there'd be a bit more low-down grunt and a bit more power up top. There would be a difference,
but it wouldn't be massive.
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hobbsy
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| posted on 24/3/10 at 08:42 PM |
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Dan has summed it all up pretty well.
I had a blackbird Fury. Blew it up in that same way. But it was very torquey and there is someone with one in a Caterham IIRC that's done 100k
miles or similar - but I don't think its tracked, only road miles (and 30k of those may have been in the bike).
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DIY Si
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| posted on 26/3/10 at 09:14 AM |
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I'd say pretty much all of what has been said above, but with a slight change.
Yes, the Bird engine is prone to oiling issues. I too blew one up this way. However, my current engine has lasted a long time and I trust it to not
blow up for fast road use. I don't hang about much on the quiet roads when I can and it's been fine. I have a sump baffle and I slightly
overfill the oil. Even if it does blow up, the current engine cost me £433, including a set of Dynojetted carbs, so I won't be too upset if it
does go. I consider the risk worth it for the more user friendly nature of the engine, with a fair bit of low down power and strong gearbox. You can
tootle around at low revs and it will pull cleanly from 2K all the way to the redline.
I would suggest you make sure you have the later clutch basket though, as both of the earlier ones that I have had have failed as they have 5 springs
rather than 6 like the later ones, and I have broken both of the outer spring plates too. Not sure why they went, but upgrading to the later ones
cured it.
Oh, also, the Bird engine sounds a lot better than some of the other BECs I've heard too. Whilst it is still clearly a bike engine, it's a
lot deeper than most others so less shrill.
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
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Jon Ison
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| posted on 26/3/10 at 09:44 AM |
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I to can offer an informed opinion, absolutely nothing wrong with the Bird engine and will survive in a 7 provided oiling issues are addressed at a
cost.
Would I fit one in a 7 ? No, would I fit one transverse in a mid engined kit ? Yes.
They can be made to survive, but if the engine bay is currently empty why put something in there that is known to be temperamental on the oiling side
of things when there are plenty of other options available, with the mods required to make it work why not fit something like a ZX12 ? The overhaul
install price will be the same ?
just my humble opinion.
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DIY Si
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| posted on 26/3/10 at 10:49 AM |
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Jon makes a good point there. If you have the choice, I would go with what he suggests and look at something else that will be just as powerful, or
probably more so, and much more reliable out of the box. Ok, it might cost a bit more, but it is one less thing to worry about.
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
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