BWS-125 in the shop

Loads of bikes come in to have work done, i just never snap pics of them!.
This BWS-125 belongs to a WWW.BWSFI.COM member, over the past few months he's been modding it, now i personally think its ugly but you have to appreciate the trick parts installed......

Ohlins rear shocks!
Forged front rim....... in green no less!
Custom made pipe (thats what he came in for)
Green paintwork

Anyway i brought the wrong lens that day so most of the pics were useless, to make things worse it was dark so lighting was awful.

Which big bore kit? ---- Z-125

Get asked this about 5 times a week, posted about it in forums numerous times but i dont think anybody reads it!.
I dont quote top speeds as its impossible to claim, but your stock bike pulls at least 55mph, everything below will nudge it past 60mph at least......... want more, you need gearing and thats another subject for another time.

(its important to note that you will need AT LEAST a aftermarket clutch of some kind in order to do any of this!)

There are almost infinite possibilitys of displacement on our engines, to save you lot time i shortened the choice down to a few sets........ well theres still quite a selection:

• 155cc
• 164cc
• 192cc
• 202cc
• 215cc
• and more if you sweet talk me via email!

Not good with tools and trying to install this yourself, skip the paragraphs below and just choose 155cc, that bolts right in place of your old cylinder/piston and can use the original pipe and throttlebody without a hitch, you can upgrade to a 32mm throttlebody later on for more power and speed if you wish.
With the right CVT settings you have around 11bhp+ with this setup.

Pretty good with tools, have good or reasonable knowledge on how a 4 stroke engine works?.
Well 164cc is the one for you and is my personal choice for our daily rider!.
Same big bore kit as the 155cc kit but with a 3mm stroker crank, this means spilting the cases (complete bottom end rebuild)
Makes more torque than the 155cc, revs alot higher, feels smoother and obviously makes more bhp.
CVT settings are very crucial for this setup, get the roller weights wrong and it will be the same as a 155cc.
To get the best from this setup you need a big exhaust (yoshimura make a good one) and a 32mm throttlebody.
Peak power of around 14-15bhp.

Sending the bike to a tuners or have done bike or car tuning before?.
Well 192cc and above is for you, reliability stays the same regardless of engine size thanks to the strong piston/cylinder and crank combo, just choose one to suit your budget.
You will need to machine/bore the crankcase, install a new aftermarket crank and head.
These engines go balistic when around 200cc, they rev to the moon (shy of 10,000rpm) and pull very hard, if your not careful from a launch you can flip the bike easily*
* I have heard of 2 experienced bike riders doing this in the past few months, im serious, be careful!.
Hard to quote figures as i have only dynoed a 223cc, but 20bhp is about right.

Hope that helps.

13 second scooter parts

Engine is still away getting coated in ceremic goodness, in the meantime i'll show off the special parts.

First up we have the 75mm piston, exactly the same as our other ones we sell just without the anti-slip coating on the side.......... why?
Well our factory cant add it when the piston is this big, plus its not that important as the bike is only going to be running for around 45 seconds at a time!.

You cant just buy a 75mm piston, it has to be specially made and only one place has the mold for it.
Yes i am tooting my own horn.

Ok here is the head with work in progress, its as big as we can go, any more larger and the gasket will not be able to seal this engine together.

 

Lastly we have the crank, its a seriously impressive piece of enginering, it weighs twice as much as a stock crank!.

This post is very brief as i have only about 5 days left until the engine must be ready, the head takes time to get right and i only have one availible to me, if its screwed up i miss the deadline........

The 13 second scooter

We have all heard the term '10 second car' thanks to the fast and the furious film series, well heres a new one for you.......... '13 second scooter' sounds like a dream but its very much a reality.
Right now in the workshop im working on a engine thats going to fulfill this very purpose!.

You probably think im just going to shove a T-MAX 500 engine into a bicycle frame, but you would be wrong.
Im actually using a humble Yamaha 125cc engine............... modified of course and using an actual  road going scooter frame!.
I wont be using a turbo, supercharger or even nitrous, this engine will be 100% N/A.

So how are we going to do it?
With some love and care we can bore and stroke the little 125cc to 331cc, yes thats over 2.5X bigger.

Now the tricks needed to stop the engine from exploding in to a ball of flames after 10 seconds i cant reveal, but i can tell the specs:

• One of our special pistons at 75mm diameter
• A extremely strong CNC 17mm stroker crank with a mother of a connecting rod
• Special high flowing 4 valve head
• Titanium exhaust (for weight reasons)
• ceremic coating everywhere
• No water cooling!!!!!!!!!!
• Extreme high compression
• Special gearing set for the 1/4 mile
• 42mm carb......... not decided on the type yet

I already built a junior version of this motor in 280cc guise and it ran 14.2 seconds with a 220lb rider.
So unless this thing explodes before it reachs the end of the strip i cant see it not setting a 13 second time.

Im hoping this will become the new category for drag racing, right now the limit is 239cc, they made this rule a few years ago when it was about as big as you can go, but thanks to recent developments in technology over 300cc is now possible.

Pictures soon...........

More show info

The Taiwan scooter show is one the largest of its kind in asia, its a pretty big deal for scooter tuners like ourselves.
This is our first event so we plan to hit the floor running with a kick ass stand and really nice products on display alot of which you havent even seen yet.

Both of our Z-125s will be there on display wearing some nicer clothes and a 52'' plasma tv showing off our videos from youtube and some newer ones in full HD.
The show is in the middle of april and it runs for 4 days.

2010 Scooter expo

Havent been doing nothing during chinese new year, these scooter shows take alot of time and money to arrange.
So far our booth is shaping up to look like this:

 

Still have lots more work to do, but its nice to see some results from all the planning.

How much power?

Its chinese new year so we are busy running up and down the country visiting family, giving and receiving red envelopes, so getting on the net is kinda hard.

But i recently came across this dyno print out from a local magazine for a competitors 155cc kit, this kit is very similar to ours in that it comes with all the parts needed to complete the conversion (fuel injector, cam etc.).
The red line shows how much more power you can make when you add an ECU and tune the a/f ratio..... i was surprised to see that it makes a large difference to the top end power, where the stock ecu just tails off at 60ish mph the aftermarket ecu just keeps on pulling to over 70mph!.

Though this is not our kit, it gives you an idea of what to expect from a 155cc conversion.
BHP shown is at the wheels.