With the bore and stroke 56.0 x 50.6mm on a stock Z125 Pro. What do you think the BBK will be? That is already a big piston in there. Maybe play with the wrist pin position and a slightly larger piston or will it have to be a crank swap? I would hate to split the cases on this new engine but it wouldn't be the first time. What do you guys think?
BBK thoughts....
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main question is how big is the case then we decide what the biggest bore will fit.
True, but keeping with that theory you could go as big as you want within the size limitation of the area under the frame, correct? As long as you keep the sidewall strength enough to keep the boom in and don't exceed what the shaft can handle bottom end can handle.
When the Grom BBKs came out they start with small increases and finally got up to the 181ish range eh. I wonder if that will be the case here as well.
When the Grom BBKs came out they start with small increases and finally got up to the 181ish range eh. I wonder if that will be the case here as well.
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It has begun. The quest for speed.
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well I know one grom big bore available is a 170cc and they can go over 200cc also but not sure how much work needs to be done to fit that large
I'm down to do one just waiting to see what comes available and how many different suppliers and how reliable the parts are
depending how large it is we may need a bigger injector too, so either we need to find a larger one off an existing bike that snaps in
or an adapter needs to be made to run a injector that is a different size
I know for the grom one injector they use is off the honda pcx I think that fits right up with no adapter and thats a 154cc engine bike but not sure how large of a big bore that can feed
and most likely will need to invest in a fuel controller, intake and exhaust to get the most out of it
I'm down to do one just waiting to see what comes available and how many different suppliers and how reliable the parts are
depending how large it is we may need a bigger injector too, so either we need to find a larger one off an existing bike that snaps in
or an adapter needs to be made to run a injector that is a different size
I know for the grom one injector they use is off the honda pcx I think that fits right up with no adapter and thats a 154cc engine bike but not sure how large of a big bore that can feed
and most likely will need to invest in a fuel controller, intake and exhaust to get the most out of it
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looks like 143cc is the biggest without boring the engine cases.
https://www.steadygarage.com/store/two-wheels/mc-parts/z125pro/143cc-big-bore-kit-kawasaki-z125-pro
https://www.steadygarage.com/store/two-wheels/mc-parts/z125pro/143cc-big-bore-kit-kawasaki-z125-pro
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so you can get away with the stock fuel injector
it can flow enough with using a fuel controller
also I wonder why they supply the large gasket, does one side cover of the engine need to come off
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and we also need someone to write a map for the bazzaz too
mnnthbx you guys getting one of these????
it can flow enough with using a fuel controller
also I wonder why they supply the large gasket, does one side cover of the engine need to come off
and we also need someone to write a map for the bazzaz too
mnnthbx you guys getting one of these????
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Hail yea!It has begun. The quest for speed.
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That'd suit my little Z just fine jim + dandy. Cheap, too!
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Running fine and dandy. All you would need is an exhaust,intake and a fuel controller. Stock injector will do the job. I would say atleast 2-3 hp increase.
Next is porting the head,cam,bigger throttle body.
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assuming u still getting the same top speed 67mph??
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Your top speed won't change unless you change the teeth on the sprockets. All that power only changes how fast you achieve that top speed.
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Steady Garage has a BBK that brings you up to 146cc. I was a little disappointed since I have seen grom BBK up to 186cc.
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why im waiting
because who knows maybe in a couple months a larger one will be available at around the same cost
or maybe same size but less cost
one thing I learned over the years is never jump in on the first parts to come out unless you like being the first one
customers seem to do all the beta testing on new things and find out all the flaws very fast if any
then version 2 comes out and solves any problems thats when I start to get interested
exhausts, body parts not a big deal
but engine parts, that can disable the whole bike if something goes wrong I sit and wait and do my research
now if these big bores that just came out have been in use for years in other countries on the z125 then I would feel its fine to purchase now
but I have not seen that mentioned yet
I do see there are 2 versions of the big bore out
one thats around $300 same size im assuming its just better quality parts?
has anyone listed the specs yet on them
like cast vs forged pistons
are they using any special bearings
any special coatings on the cylinders like niksal or however its spelled??
compression ratio
can I use pump gas, or do I need to use high octane
or are different base gaskets sent so you can decide on what compression ratio you want to use?
because who knows maybe in a couple months a larger one will be available at around the same cost
or maybe same size but less cost
one thing I learned over the years is never jump in on the first parts to come out unless you like being the first one
customers seem to do all the beta testing on new things and find out all the flaws very fast if any
then version 2 comes out and solves any problems thats when I start to get interested
exhausts, body parts not a big deal
but engine parts, that can disable the whole bike if something goes wrong I sit and wait and do my research
now if these big bores that just came out have been in use for years in other countries on the z125 then I would feel its fine to purchase now
but I have not seen that mentioned yet
I do see there are 2 versions of the big bore out
one thats around $300 same size im assuming its just better quality parts?
has anyone listed the specs yet on them
like cast vs forged pistons
are they using any special bearings
any special coatings on the cylinders like niksal or however its spelled??
compression ratio
can I use pump gas, or do I need to use high octane
or are different base gaskets sent so you can decide on what compression ratio you want to use?
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Good post^^ Sometimes it pays to wait. There are things I want that have not been created yet for this little thing but give it time and I bet we will have close to the same number of options as the Honda.
Looking forward to a BBK myself but will probably hold off for at least a year on that one. Suspension will be first up.
Looking forward to a BBK myself but will probably hold off for at least a year on that one. Suspension will be first up.
The fuel injected Z125 came out in November 2015 in SE Asia. The bike the Z125 replaced, the KSR110, had a carbureted version of this same engine. There are plenty of bigbore parts for the carb motors from 138cc, 143cc, 178cc and beyond but the EFI motor has enough differences that you can't just bolt on those parts. At least not until the fuel mapping is altered for the larger displacements and is reliable enough for everyday use. I'd say there are plenty of people working on high performance parts but it's still early days in the development process. You'll just have to be patient a little longer...
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