Question Its a downsized 07-08 R1

[KillerwhaleTRX]

So, i have not got the bike here yet but plowed the internet and forums every evening since my deposit.....
The stroke is the same as the R1.....(saw what the italian dude did to his bike and it sounds great!)
So FZ8 bore is 68mm & R1 is 77mm.....50cc per cylinder.

Do you reckon there is enough meat on our cylinders to bore it to 77mm??
And if it is, is it the same piston/crank pin diameter? I read they only lightened the R1 crank but the pin should be same no??

ps. posted an introduction at the forum a minute ago,,,,,

 

[Satan666]

The answer is no to the 07-08 R1. The FZ8 engine is a variant of the 04-06 R1 and little brother to the GEN II FZ1.

In addition to the piston diameter difference, the FZ8 has smaller valves, ports, injectors, throttle bodies and exhaust pipe diameter which limit gains from a bore size increase. Because the FZ8 combustion area is smaller, compression will increase to about 13-1 and premium fuel will be needed.

You would be far better off swapping a used FZ1 Gen II engine, exhaust headers and call it a day with an extra 30 or so horses.

You could also swap the 04-06 R1 engine and FZ1 header but the horsepower gain is minimal and all at the top end, making low speed riding tedious.

ECU tweaking required.

Prepare to break drive chains unless you upgrade to 530.

Sounds like you are buying a great bike, especially with the upgraded suspension.

Dreamers attempt to make a silk purse from a sow's ear and foolishly spend all their gold.

Ride more, dream less.

 

[KillerwhaleTRX]

Very very strrange, all magazines here when FZ8 was new states 07-08 R1 derived,
Also the bike in italy used the 07-08 head, cams, pistons cylinders and injection from the 07-08 R1.
Another guy in the states used the 07-08 cams as they are just to install in the FZ8...

Yes i have read for hours last ten days

Cheers
Mattias

 

[KillerwhaleTRX]

Also the FZ1 head is a 5 valve jobbie where FZ8 has 4 just like the 07-08 R1.....maybe som mishmash of things....but just what i read anyway.

 

[Satan666]

I stand corrected on the lineage years.

Parts fiche gives different #s for the piston pin but the connecting rod appears to be the same (R1 # recently updated.) It might be easy enough to swap the '07-'08 cylinder bank along with the R1 pistons, pins and R1 head gasket to get you to a liter. Might be interesting to see if you get more low end power.

However, all of the other performance issues remain as the FZ8 fueling & airflow was set up for 20% less. -5mm on the intake and -4mm diameter on the exhaust valves. Change out the cylinder head, exhaust, throttle body and injectors? Cam chain adjuster? How long will the FZ8 clutch plates last? Transmission? Upsize the drive chain, rear wheel & tire?

Engineering is an exact science especially when your are balancing performance and cost.

Keep us in the loop if you decide to get your hands oily.

 

[KillerwhaleTRX]

Here you can see what LKM tuning in DE does to get 113 rwhp.....Not cheap at all!! But they do the valve seats... https://lkm.de/tuning kits/fz81_10.htm
If i would have a guesstimate. If one does a head flow job (plastic inlet & welded exhasts) put the R1 cams in and just standard pistons but high comp 13,5;1
You have a very very nice FZ8....wich still is an 8.... ECU flash and dyno of cource.
I wonder if the Rapid bike EVO box can autotune that.....interesting piece of kit!