710cc big block for the 550

I discovered this shop in Japan that does a lot of 400/550 bore ups to 710cc. Looks like they sell a 710cc big block cylinder. I have seen the future of my bike

himeji-gs.com/?page_id=2591

If you use the Chrome browser to access the site it will translate it into English.

I don't know how much it costs. I'm guessing not at all cheap.

$6130 USD for a big bore engine build. he only will do complete engines.

There are probably other ways to get there a lot cheaper. I think a ninja engine would be a cooler mod, or better yet a turbo Zr.

Have you seen Glbishop's project?
It's posted for ignition-related issues, but you can skip all the ignition talk.
www.kzrider.com/forum/4-electrical/61224...g-above-10-lbs-boost

DoctoRot wrote: $6130 USD for a big bore engine build. he only will do complete engines.

youch. I guess that's not surprising given all the work they're doing. I wonder how much it would be for just the cylinder head and pistons/rings ( if they were to sell them.) If it were $2Kish I'd probably go for it. I could rationalize that kind of expense thinking how much it would save me if it prevented me from buying an expensive new bike

loudhvx wrote: There are probably other ways to get there a lot cheaper. I think a ninja engine would be a cooler mod, or better yet a turbo Zr.

Have you seen Glbishop's project?
It's posted for ignition-related issues, but you can skip all the ignition talk.
www.kzrider.com/forum/4-electrical/61224...g-above-10-lbs-boost

Yeah, Gary's project is incredible, though a similar one would be way beyond my skill level and available time.

There was a write-up on the Zephyr Zone about a sweet ninja engine swap, though that thread and a bunch of others got lost some time ago. That said, I really like the look and character of the stock air cooled engine. I'm even happy with the power my current engine is making, though it's got almost 70K miles and I imagine it will need some work at some point soonish. In which case an overbore could be in order. If I extrapolate from Corey's 65 rwhp/39 ft_lbs with his 615cc engine to the 710cc motor, I'm thinking it could make ~75 rwhp/45 ft_lbs, which could probably keep me happy the rest of my life.

If building big bore bikes made financial sense then everyone would be doing it! I tell people about the tens of thousands of dollars I have poured into customizing bikes over the years and people always ask why I don't just go buy a new bike with more power and better handling for less money. Bottom line is you can't buy a bike like this and ultimate performance was never the intent.

While 6k seems like a lot of money for an engine, consider this; a 750cc super-sport engine is probably about 2/3 to half of a full motorcycle retail price. So 6k is very comparable to a brand new engine... which is what your getting. I imagine he needs the whole engine because a bunch of other machining operations need to be completed as well like boring the cases for bigger sleeves and reconditioning the connecting rods to handle the massive increase in power.

You could put together your own kit for about $2500.. I recently shopped around for prices on my custom big bore setup for my twin so i can tell you that pistons go for around $280 per piston, 150 per custom sleeve, 120 per hole to press out old sleeve and bore for pistons, $60 custom gasket. Boring the cases is probably another 250-300.
$2560 total

the problem therein lies that you probably want to address the head with a port and polish, probably a bigger intake valve, custom cams, better carbs, etc then yours 6K deep. lol. I think i will have about $3500 on my "all out" 906cc street twin. Does it make sense to put this amount of time and money into a bike like this? hell no. But dusting unsuspecting Harley owners and Bonneville cafe posers will be well worth it.

The turbo route is a definitely a cheaper way to get to the same power numbers while also retaining reliability.... plus you got a freakin turbo! the noise and look alone make it worth it.

6 grand for a built high performance motor is really a deal deal price. Like DoctoRot explains all those fancy parts add up real quick. One-off parts are even more ridiculously priced. Another bad thing about one-off parts, you better order at least one more for a spare just in case the first one wears out or worse yet blows up!!!!!

Another thing most people don't realize is your fancy motor is only as strong as its weakest part. I have seen people put a small fortune into a motor and use a part like that cam chain that only has only a few thousand miles on it instead of a brand new one. Well guess what broke and wiped out their mega-dollar cylinder head. Its funny I used all the very same parts in my 1015cc Superbike motors that almost every other racer used. I have seen other racers with the same parts that are in my motors suffer some major engine problems like burnt pistons, dropped valves, and worse in their motors I never suffered any type of motor blowup. Missed a few gears and bent a few exhaust valves and thats about it. Sometimes it just might be who or how all those mega-dollar parts were put together!!!!