FZ8 with a big (R1) Heart!

[Blackfin]

If you go to larger pistons but retain the same crankshaft would you not have severe balance issues?

Love the idea of modding what you got but for that much effort and expense, why not just sell the 8 and get an FZ1 or an R1? I know some people don't want to hear it but it makes the most sense...

 

[Jubby]

If you go to larger pistons but retain the same crankshaft would you not have severe balance issues?

Love the idea of modding what you got but for that much effort and expense, why not just sell the 8 and get an FZ1 or an R1? I know some people don't want to hear it but it makes the most sense...

Don't say things like that people jump out of the craks!! It would only be parts, some additional tools, ECU flash and Dyno tune.. And i love the look of the FZ 8 or 1. Having a bike stamped 8 that does what it should not appeals to me.

crankshaft and balancing issue is someything i have not thought about.... i honestly dont know about balancing issues.

Thanks for making me aware of this.

Isn't the crankshaft the same as its the same block as the R1? the crankshaft should still spin the same shouldn't it? A lighter crankshaft would get you up to speed or inertia quicker but i cannot see how it would effect your balancing? The stroke is the same as the R1 so the FZ8 conrods should be able to be used.. But i aint no expert so i may need to research the balancing thing.

All this mod is is research i don't know if anyone has done it but i know it is talked about alot. I guess it gets to the purchasing goods parts and people just go errr not sure if this will work buy the goods. Then get to the wrenching bit and go errr no this might even work. im off to get a FZ1. I am kinda at the Purchsing bit. I have the R1 Cams and valve springs etc as i know this has been done previously but im thinking the whole lot can get swapped - surley... Well I hope.

I got the bike cheap much cheaper than a R1 of the same age and miles and if i can get the same performance with them extra dollars = HAPPY DAYS!!

 

[Blackfin]

Don't say things like that people jump out of the craks!! It would only be parts, some additional tools, ECU flash and Dyno tune.. And i love the look of the FZ 8 or 1. Having a bike stamped 8 that does what it should not appeals to me.

Yeah, I definitely dig that. If I had endless funds I'd fab up a low-pressure turbo system for my Fizzer. But I don't have those kinds of funds lying around nor the time to do such a thing. I'd just end up "trading up" to the faster bike. I definitely admire those that go through with stuff like this.

crankshaft and balancing issue is someything i have not thought about.... i honestly dont know about balancing issues.

Thanks for making me aware of this.

Isn't the crankshaft the same as its the same block as the R1? the crankshaft should still spin the same shouldn't it? A lighter crankshaft would get you up to speed or inertia quicker but i cannot see how it would effect your balancing? The stroke is the same as the R1 so the FZ8 conrods should be able to be used.. But i aint no expert so i may need to research the balancing thing.

The counterweights on the crankshaft balance out the forces generated by the reciprocating assembly -- the rods and pistons. Heavier pistons generate higher forces and require larger counterweights (or heavier counterweights if one goes the heavy-metal balancing route). My understanding is that the FZ8 engine is basically an FZ1 engine with a 4V head, reduced bore and lightened crankshaft. I'm not certain how much lightening was done for "quicker response" and how much was done to account for the smaller bore pistons. It could be that an FZ1 and FZ8 piston weigh the same and the balance concern is a non-starter.

I don't have much experience or time with the FZ8 but I hadn't heard of anyone going this far (i.e. swapping cylinders, pistons etc). The R779 mod -- using R1 cams, for example -- is about the upper limit of what I'd heard. I'm not sure if you're in uncharted territory or not but please post a thread detailed pics & text of your progress.