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using a fazer engine to replace r1 lump
crimondbanger - 30/3/24 at 08:27 PM

Anyone used a fazer 5lv lump 2002-2005 to replace a 4xv /4jj or 5pw r1 lump?

My r1 is pretty tired and second hand ones are getting scarse , wondered if I could put a fazer lump in as could pick up a whole bike cheaper than a "maybe ok" r1 lump.


TimC - 2/4/24 at 03:25 PM

Ah - I honestly thought that I was about to be the oracle on a topic.

I'm presently coming to the end of my 4C8 R1 (kept killing these) to 5VY FZ1 swap.

For what it is worth, most of the engine 'architecture' is the same in my case - except the bl@@dy exhaust ports which are at a different angle meaning the original manifold bashes into chassis!

[Edited on 2/4/24 by TimC]

Curiosity got the better of me. This is on an R1 forum:

For anyone searching for this.

The cam timing is different on the 5LV so you'll need the ignition box from the Fazer - the Fazer has a lower rev limit as well, it cuts directly on 11.5K whereas the 4XV revs a little into the red-line before cutting.
The carbs are mounted differently to the 4XV, the carbs are also slightly smaller in diameter than the 4XV's.
The clutch mount is on the top of the crankcase, not the bottom like the 4XV.
The clutch cover on the 5LV is smaller than the 4XV.

These are the only things I noticed when swapping a blown 5LV to a 4XV (installed in my kit car).


[Edited on 2/4/24 by TimC]


crimondbanger - 4/4/24 at 05:07 PM

cheers , thanks for that .


Minicooper - 5/4/24 at 10:04 AM

10% heavier flywheel which could help in a car, major benefit for the bike engined crowd is horizontal carbs as opposed to the downdraught carbs on the R1 which should make fitting under an unmolested bonnet a beeze

David