Advice on 2005 yamaha BWS with 70cc BBK -

[nadroj]

Hi there,
I just bought a 2005 yamaha bws "50". It came with a 70cc polini sport kit (unsure if 10mm or 12mm), and polini main carb jet kit (unsure of which jet size they decided on). Everything else is stock.The carb, fuel petcock, electric starter, and oil injector were all replaced at the same time as the polini BBK.
The bike was brought to a bike shop and the carb was tuned by them about a month ago. I just want it to be a dependable nearly daily driver. Is there anything else I might need to ensure reliability/ longevity with the 70cc upgrade ?

I have done a fair amount of reading on this subject but I get a little lost as most people can't seem to stop at this point and just keep upgrading which I can completely understand

Currently it has decent bottom end power and a little bit more top speed than stock (70ish km/h on flat). Certainly not set up to extract every ounce of speed/power

Any advice is appreciated
Thanks

[aeroxbud]

The best thing you can do to prolong the life of a two stroke is use a quality oil.
Did the shop replace the oil injection pump, and the gear. The
Plastic gear can wear over time. But it's generally a very reliable system.
If you have just brought it. I would check the CVT for wear, and just do a general inspection.
I would replace the brake fluid and transmission oil too. It's an old scooter and this stuff is often neglected.

[Zino]

Only non performance part I call a must have is a temp gauge
If your jetting never maxes above 350 on long wide open runs your on the safe side of jetting .

the bbk  is the biggest bang for the buck mod and the polini kit is a very reialble kit

Next move would be a better pipe either a street pipe that looks like stock tecnigas silent pro or malossi wild lion are great choices they woul giver better take off and more top end and you could leave the stock cvt as is or go with medium strength clutch springs and possibly 1/2 gram lighter roller weights to make it spunkier you might have to upset the carb
Cost of this upgrade under 200 bucks it would add 3to 5 mph

Or get an expansion pipe yasuni r or yasuni z are great pipes you would need to do more extreme fine tuning with the cvt otherwise you will not match up to the power and of the pipe you would need hard clutch springs possibly medium and a range of variator weights which means you might as well get a better variator malossi and polini both wood give better shifting and a few miles up top
This would bring you around or over 400 bucks Properly tuned this could add 5 to 10 mph

[bigmatthew86]

Zino knows his stuff. I’ve ran expansion pipes & they are faster but are louder & draw more attention. If you’re just wanting a daily driver a street pipe is where it’s at. You definitely gain some power & several more mph while looking & sounding pretty much stock. I have a wild lion/polini speed pipe on my 70cc vino & I love it.

[nadroj]

Just getting the hang of this forum. didnt know how to see replies. Thanks for the responses!

The oil injector was replaced but likely not the plastic gears (I'll check those). The previous owner only ran lamalube and gave me a bunch of bottles so that's good. After all the reading up I am definitely going to buy a temp gauge. Good call on the brake and trans fluid change - will do. And yeah I will likely eventually upgrade to a tecnigas silent pro to keep looks and sound down.

Would carb tuning be a must for the silent pro upgrade ?

[bigmatthew86]

Might can get by without but that is where a temp gauge makes tuning so much easier. I can do it without but for how cheap a gauge is I wouldn’t. Just aim for the temps to peak around 350 & you’re golden.

[nadroj]

I will definitely be getting a temp gauge this paycheque.

Now to figure out why my brand new starter won't quite start the bike. Been reading that it might be the wire gauge is too small

[Zino]

does the electric start make any sound when you turn the key ?

The silent pro exhaust may need some tuning on the carb sometimes you need to upjet from a 80 to a 82 or 84 main jet if you use genuine Yamaha jets .Most times you need to find tune the needle by richening it up by dropping the clip on the needle .

[nadroj]

One time it started after a full charge on the trickle charger first try on a warm day but otherwise it consistently will just about start but not quite ( it has brand new battery).

I have a polini main jet kit sitting in a bag of spare parts so I will be prepared to upjet and or adjust the needle if (when) I upgrade the exhaust thanks

[Zino]

sometimes the 70cc run higher compression and that makes stock batteries struggle

kick-starting has that cool factor too it
my vinos have to kick start from cold because of the malossi kits

[nadroj]

I kinda figured it was due to the extra compression. Oh well. It kicks over like a dream.

Next question, now that I'm riding a scooter surrounded by terrible drivers that keep trying to kill me.

Are the 4 piston brake calipers worth it for extra stopping power? RNC or Adelin