Boring VS Stroking: More CC that is

I have a 2005 zx6r (636) which i use on track as much as i do street, but would like to get a little extra power from it.
i Have gone as far as i can with the bolt ons and have a complete worked head, degreed cams and bumped compression, but would like to get more in the 750cc rang for power.

The 2 options is 2mm overbore...OR...1mm stroke...

Any major PRO's VS CON's as i know both will cost $3,000-$3700 depending on which way i go, can do most assembly and set-up myself.
Thoughts on using reconditioned rods with ARP rodbolts, or the ever pricey Carillo's.

If Stroking and going with aftermarket pistons (could i use the stock pistons?), do i need to have the cylinders replated?

Any input would be appreciated as built car motors & done head/cam work but not lower end.

 

really?? how are your two options "2mm over" or "1mm stroke"

who makes a 2mm piston for the ZX636 (even if you had custom, WHY?) then why or who would waste $$ stroking a bike 1mm...040" for what? 4hp?


Best thing yuo can do to that bike is THROW RODS IN THE TRASH! Dont try going over 125rwhp (easy to get) on them with oem rods..just a matter of time until they throw themselves out!

Put in some carrillos, get bottom end blueprinted/ss/whatever you like to call it RIGHT, increase compression a bit, throw a RR head on it, GOOD full system like Leo or Akra, change the stacks around to get power where ya want it, and enjoy a nice strong 125+rwhp bike.

 

Umm GSX-R 750? Sell the kawa and get a "bigger" bike. seems the cheaper more reliable way to go

Also plenty of liter bikes to choose from. for what your trying to do. at some point your going to end up with an unreliable nightmare.

 

i don't know if this guy's ever done motor work before but i'm pretty sure he's slept in a holiday inn

 

For the life of me, I can't think of a better way to throw money away. As the EDR guy said, the bottom end won't take it. Period. Buy a 750.

 

Sell 636 ~$4000
Engine rebuild money ~$3000

Equals $7000 for a seriously nicely prepped 750 or 1000 that'll run low stress forever versus a timebomb 600.

 

i don't know, sounds too logical, seriously though, unless you are worried about tryinig to cherry pic a 600 series get a bigger bike

 

We made 2mm pistons for the 636...it makes it a 674cc motor and made well over 130hp on pump gas.

To the OP, I would not stroke a ZX636R.

 

like i said, you can get custom, but why? those engines are weak when power gets up there.

Sell it and buy a 750..when you get tired of that 135hp..do a 3mm big bore and enjoy 160+rwhp...

 

We have built 3 of the 674cc motors....all with Carrillo rods and they are all running today as far as I know. Decent power and very reliable.

That being said....a 2006 ZX6R would not be my choice as a race bike.....but people race/build different things for different reasons.

Hell....I have a 636cc ZX-6RR (The 599cc version) with a whole bunch of work done to it.....and it went over 190mph at Loring, ME at the top speed event....World Record for the Modified 650cc Class...

 

Sounds like i will stick to the 2mm overbore option....if it runs $3500-$4000 i am fine with that, as love the bike and its just money in the end, if i get the performance i am looking for i can live with that .

AS for the whole buy a bigger bike, i already have that option sitting in the garage next to this bike (zx10r,1098) but no middle weight bike 750 & i just plain wont buy a GSXR series bike.

ED WHO?
So did you tell the guys who had their R6's built at your shop (on your webpage) to get GSXR 750's as well?

 

No, the R6's he builds make most 750's look stupid

 

Yeah as guys wanted an R6 with more power, not a GSXR 750.
Kinda where i am with my bike..if kawi made a newer 750 i would of bought that but since they dont 2mm overbore it is.

 

FYI, Eric builds bikes that fit into displacement limited classes. The 600 Superbikes he builds are legal for 600 Superbike. Your 674 would not be legal for any 600 class and would have to race against 750's. Hence the comments to get a bigger bike, not build up the 636.

There is a lot you can do to the engine before going over bore or stroke to get more power, and it would still be legal to race in the 600 Superbike class. Assuming it's a race bike, of course. If it isn't, I understand you wanting a project, but remember that this is a race forum, not a trackday or street forum, so everyone assumes you are building a race bike. Hence the comments about getting a 750.

 

yes i would! If they had stocker, we could SS prep it and get them 124-129..if they wanted mroe, we could do the 2mm kits(636) with rods and get mid 130's with much more midrange...they want more we say "sell it, buy a 750"

Look you can spend your money how you want, but as i said WHY would you want to on that bike? its not a great platform for big hp..dont take personally. The transmision are gabarge (compared to others) the lower end is VERY VERY proven weak (Rods help a ton).. my point was more that WHY would you spend thousands to stroke a bike 1mm?? If your gonna stroke it, do a 4-5mm stroke.

Personally if i had a ZX636 i would put a good ported RR head on it, have a set of custom made STD bore pistons made but with single ring/relocated wrist pin, use a custom carrillo rod that is longer to work with piston (long rod motor) then get crank REALLY well done (mag if high miles, then race balance it and have it REM ISF treated and enjoy myself a killer bike with mid 130rwhp. Anymore than that, id buy a 750 or 1000.


but thats MY choice, yours maybe different.i dont get why guys ask questions on "what should i do" and someone gives their $.02 only to have the OP question your response..mines not maybe what you want to hear, but it is my opinion, just like Chip has his, topher had his, etc.. best of luck with whatever ya choose.

 

BINGO! Thanks PScook for explaining.

Again to the OP...best of luck with whatever you do, just know its very common knowledge that is not the toughest/most reliable "600"bike to be start adding a ton of power, rods or not.

 

Because "any input would be appreciated" directly translates to "any input would be appreciated as long as it fits in with what I want to hear for answers".

OP - Try more gas, less brake.

 

Well i do appreciate the time your have spent on giving me some info ED, as if you would of posted the last post 1st i am sure i would have been far happier with the response on the thread VS all the in between chit chat.

My realistic goal is a reliable and usable 130rwhp on pump gas, so 8 more than where i am at now.
Bike has head work, degreed stock cams, Beet full system, factory pro stacks, kit ecu (tuned by a top Italian SS team), is a pretty solid performer and not used in racing just trackdays and street riding.

 

130rwhp on pump easy on that bike.

1. Superbike head (Portwork, surface, valve job, cam timing, etc)
2. Increase compression with good pistons, JE, CP, Wiseco, etc
3. CARRILLO RODS!
4. Kit ECU tuned well
5. GOOD exhaust (like Leo Corsa or Akra)
6. Shorter stacks(might have to play with lengths depending on pipe), BMC filter

That should get you in the high 120's easy, maybe even 130rwhp. a fully ss legal (not that 636 are ss legal, just saying same type of build) on pump will make almsot 120rwhp all day long...so the head work, increased compression will get you there or close to it. Want more, then do a big bore as Chip says they have, but i would not run pump gas on a 2mm over kit unless you play VERY safe on the timing.

Good luck

 

Hey Ed, I'm pretty much building exactly what your are talking about, but with an 08 zx6r. The stock rods look tiny and weak compared to the carrillos.
I have 2mm CPs, kit cams, vstacks, KIT ECU, full arrow system, K&N filter. I had a couple of questions and I know for a fact, that your the right guys to ask.

1. How high of octane should I run...probably depends on how tight I build the motor and how much the ignition advancement hey?

2. What grade/viscosity of oil should I run in a hi-comp motor?

3. Do you think its worth selling my K&N to buy a race BMC?

I appreciate your time.