nc21 engine

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clearblu
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Posts: 26
Joined: Tue Jun 28, 2011 8:08 pm
Bike owned: vfr 400 z
Location: Liverpool Lar

nc21 engine

Post by clearblu » Tue May 07, 2013 4:08 pm

Hi Guys,
Haven't paid the forum a visit for ages due to work and medical woes (arm op which stopped me riding,cue depression and avoiding reading about bikes :( )
Anyhow my 400z has proved an unlikely inter continental ride and has travelled to Ibiza,Spain and Portugal on several occasions and has not skipped a beat apart from a couple of flooding problems.It was a complete accident using the bike as Id misse my flight and couldn't get another for 4 days,deadline to get to work was 4 days so I decided to take the bike,I'll post the story and stand pics on a new thread.Anyway the old girl needs a bit of TLC now engine wise as It's down on 1 cylinder after all the abuse I hurled at her lus a naughty float bowl causing the flooding and no prizes for guessing which cylinder is down.She is still putting a healthy 56bhp on the rolling road but the lads have suggested a rebuild.
The question is what engine parts are still available?
I realize for the cost of a rebuild I could probably get a ratty nc30 but I love this bike and prefer the characteristics of the180 degree engine to 360.And I love bombing past modern tackle on my skinny 130 section tyre!
Cheers Gareth

clearblu
Settled in member
Posts: 26
Joined: Tue Jun 28, 2011 8:08 pm
Bike owned: vfr 400 z
Location: Liverpool Lar

Re: nc21 engine

Post by clearblu » Wed May 08, 2013 8:01 pm

Just checked the vin number and It's a 24 engine fitted (the lack of hydrolic clutch should have given it away).
So any suggestions would be great, just read the dyno print out r.e. compression and the lads are only going to charge me 'A favour' as they look after my two strokes.I may splash out on New downpipes and a collector box whilst this is all been done ;)
Where's Neo when you need him.LOL!

clearblu
Settled in member
Posts: 26
Joined: Tue Jun 28, 2011 8:08 pm
Bike owned: vfr 400 z
Location: Liverpool Lar

Re: nc21 engine

Post by clearblu » Thu May 09, 2013 11:54 am

Hmmm,now the plot thickens it turns out the frame is a nc21 (one of last numbers in the register 87, code zh) with an early 24 engine,but with the low level exhaust as per the standard 400z.Question is was this a late 400z with a 24 engine factory fitted? It was imported in 92 with the engine fitted ( all docs back this up ).

Neosophist
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Re: nc21 engine

Post by Neosophist » Thu May 09, 2013 1:36 pm

Hey.

Are you getting the VIN / Engine numbers from the haynes book, I really wouldnt trust them so much as that book is full of mistakes for NC24/21 anyway.

What is your ECU setup like? Do you have a single ECU under the rear seat or a unit by the battery, this will help determine what engine and wiring loom you have fitted.

Hydraulic clutches can and do fail so perhaps it is really an NC21 engine just with the later cable clutch fitted.

Carbs are different too, 30mm vs 32mm but they can also be easily changed. type of ECU will be the biggest give away as there not changable without wiring changes (NC21 has camshaft position sensor that the NC24 doesnt).

As for new engines if its not broken dont fix it, whats your compression like? 56 seems good power, I think you will struggle to get much more.

I would use that engine until it really dies and spend the money you would have spent on a new stainless steel downpipe and linke pipe / end can.

If you have the low level exhaust then you most likely have the NC21 collectorbox and of course the NC21 footpegs as it bolts to them.

If you want to fit the high level exhaust you will need the NC24 rear pegs (bolt to either subframe) but are a diferent shape for the high level exhaust.

I cant remember off hand if the ehaust hanger is welded to the NC24 subframe or part of the footpegs.

Anything else you need to know just ask
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...

clearblu
Settled in member
Posts: 26
Joined: Tue Jun 28, 2011 8:08 pm
Bike owned: vfr 400 z
Location: Liverpool Lar

Re: nc21 engine

Post by clearblu » Fri May 10, 2013 2:34 pm

Hi Neo,thanks for the reply I'll check the bike this weekend.From memory there is possibly a cdi under the rear seat,I remember there is a small box marked 'Oki Electro industry' with a 4 way and 6 way Molex plug on a short flying lead that terminates on the right hand side of the frame.I checked the engine number from the forum list and the frame the same way.It has nc24 forks as well.So its a 21 frame,24 forks and engine.
You always amaze ne with your knowledge of early vfr's ;)

Neosophist
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Re: nc21 engine

Post by Neosophist » Sat May 11, 2013 3:27 am

hah thank you, but theres proabbly an awful lot I still dont know.

Anyhow

Image

this is a picture of an NC21 engine.. if you look in the V of this engine you can see the camshaft position sensor bolted onto the front, this is missing from an NC24 engine.
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...

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