Big Bore Kits on Honda Shadows: What are my options?

on June 26, 2019

Today on the blog, we’re exploring your options for adding a Big Bore Kit to your Honda Shadow. Is it possible? Is it advisable? What would TJ do??? Now go grab a cup of your favorite brew and sit down for a little schoolin’!


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A customer wrote in asking, “Can I add a Big Bore Kit to my Honda Shadow VT600? Where would I find one?”


The short answer is NO – don’t do it! The Honda Shadow VT600 is a 600 cc bike. You really can’t bore enough out of it to get a serious difference. This customer is obviously looking for more performance but that’s not the route to go. With the Honda Shadow VT600, you have the problem of only being able to go *so* big with the cylinder before you start making those walls super thin. There’s a water jacket in there and the cylinder is not that thick. You’d need to beef up your clutch, too – and you still can’t do anything with the gearing because it is what it is.


Honestly, if you bored out a Honda Shadow VT600, you’d end up winding out the gears much faster than you normally would—and not getting the end result you’re really looking for. Ultimately, the cost vs. return on investment says you’re better off stepping up to a bigger displacement bike. As they say, “there’s no replacement for displacement.”


LISTEN UP: “There’s NO replacement for displacement!”


Motorcycles as an “investment”: the TJ Brutal Customs perspective

Speaking of investment, there are actually very few vehicles that would be considered an investment. In most cases, a vehicle is a liability unless you have a vehicle that’s used as a tool to accomplish a job (i.e. a crane). Most passenger vehicles are not investments. They’re considered a liability because they decrease in value the moment you purchase them. If you overuse the vehicle, it wears out faster. Underusing it has its downsides as well: letting a vehicle sit unused will hasten the demise of the vehicle much faster than daily driving and regular maintenance would.


Even collectible vintage cars aren’t traditionally considered an investment. In most cases, you’ll never get the money out of it that you put into it. The same goes for classic cars—even bikes. You can pay $8-10K, $20K—even $150K—for a custom motorcycle, put a little work into it and then try to sell it but you’ll still get a fraction of what you *think* it’s “worth.”


When people come to TJ Brutal Customs to help build their custom bike, we let them know they’ll be putting more money into it than they’re going to get out of it—and they need to be “OK” with that. If you want to sell the custom motorcycle or bobber you’ve put a lot of work into, you likely won’t get back the investment you put into it. There’s just no guaranteed ROI. You can’t invest in a “liability.”


But what if…?

Back to the customer’s original question: if you do try to bore your Honda Shadow VT600, it won’t be worth it. The current bore and stroke on a Honda Shadow VT600 is 3.0 x 2.6 or 75mm x 66mm. If you decided to bore up to .010, you’d gain 4cc. That’s it: FOUR cc!


That’s nothing!


There’s a reason bikes jump from 600 cc to 750 cc to 1000 cc to 1100 and so on. Motorcycle models make pretty big cc jumps—usually in the 100s. When you compare rides, it’s a pretty noticeable jump, whereas jumping 4 ccs is literally nothing. You won’t even notice it.


If you want to put all that time, money and work into trying to bore out a motor that’s only 600 ccs—and really wasn’t designed for that sort of massive boring—then so be it, but we don’t recommend it.


Bottom line: if you’re trying to get a faster bike, just move up to a bigger displacement bike.


Honda stock bores

Honda makes 2 sizes up from stock bore: 2 different pistons and 2 different types of rings. So, if you need to hone the cylinder out or bore it out a little bit bigger (due to corrosion or a motor issue), you can go up to 25-50 (varied) increments above your stock piston and rings—but you won’t feel any difference in the power or performance.


For more specifics on bore options and Big Bore Kits for Honda Shadows, watch this video:

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Looking for something else? Explore our Honda Shadow collections below: 

VT600 Collection
VT750 Collection
VT1100 Collection
Phantom VT750 Collection

Aero VT750 Collection

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