Yamaha BWs NG-Wheelie bike

[bigmatthew86]

I can’t make you any promises but mine was running good until I sold it.

[Kagouras]

appreciate your help guys

[sinfull]

Put the new parts on and see if it makes a good change.

If you can afford it, before the new cylinder and everything, purchase a temp sensor gauge, install it correctly and see what you are actually running at. No use in new cylinder if you can't monitor your tune.

Temp sensor is the easiest way to find out what is going on with your fuel.

[Kagouras]

Can u send links for cheap gauges?
Three months now i push bike day by day.me being 90 kg,extreme uphlls,full throatle for 3-4 km untill i smell 2t to the socks.i cant hurt it even if im trying.
i also checked spark plug and it seems im running very good right now
i hope bbk is reliable like the stock

[Kagouras]

i was ill and today i feel a lil better.i didnt go for work and we have summer weather,so i decided το work with the bike.
i put the malossi filter and the results are dissapointing.maybe i have couple km better top speed,but acceleration is much less and the exhaust is making some weird noises at wot.also when i ran it for first time with the filter and i went full throttle for couple miles the exhaust was spitting a ton of white smoke
i also went to the guy with the exhaust repair/shop,and i told him to remove the restriction at the back side of exhaust.cause i dont have a dremel
i will go back and get it after 2 hours bcs he was extremely busy

[Kagouras]

oh i forgot to say sth important. i also bought a used airbox.before i fit the foam filter,i just changed the airbox and tried the bike with the new airbox empty,exactly as i ran my bike before with the old one.the results was the same,no difference at all at perfomance.my old airbox had the snorkels totally removed,the new one is stock.
i dont get it...maybe the filter block the air and thats why the bike cant accelerate like before??
im desperate i cant even wheelie.the bike is lacking power
im cooking atm bcs im hungry as hell,when i ll eat ,i go back at pantelis shop and grab my exhaust
its gonna be a hard afternoon

[bigmatthew86]

You don’t really gain anything running an open filter & it makes it harder to tune. I’d run the factory box & filter with the snorkel removed & jet to match. If you’re running & open filter & didn’t up jet you’re running lean & can damage the engine.

[Kagouras]

ok exhaust and and new intake are on the bike.just from the sound the bike makes,i can say it has more power and it revs higher.i saw a great top speed increase,about 10 km/h or sthing less.im really impressed.

the bad thing is she still has acceleration problem-from the ear i can say its carb/airbox related

at low revs air/fuel percentage is not correct--->too much air
and i also found why this is happening,and also why the bike is running better with eempty airbox
Both my airboxes have cracks and air is slipping in,im extremely dumb and unlucky
next day i have to fix the problem and check variator/clutch/belt for first time
i will insert more photos from my bike and the repair shop we do our things.its local kawasaki partner and you can find other used and new bikes to buy there.a lot of interesting staff.today we sold a derbi gpr125,what a lovely bike

[Kagouras]

ok i have no idea whats the problem
the bike just bogs like hell and is having a real hard time to reach top speed

[Zino]

Your top speed is good and you have power .
Since you changed the pipe your power band may now be starting a notch higher .
You may need lighter weights by a half gram to a gram ligher than what you have .

If you roll slow for 10-20 meters and then pick up speed
Try a notch stiffer clutch springs .

[Kagouras]

ok so i think Zino is right.i fitted old exhaust and i have better response and low power,so my new exhaust need lighter rollers or stiffer springs.
but i noticed that the bike isnt as strong as it was before i change belt.so i have some loss from the belt also.

the problem is i threw old belt to garbage

[Zino]

So you are not chasing multiple gremlins
focus on balancing the transmission first
Work back to front
swap in a notch stiffer clutch springs
run it down the road see if you notice a difference on how it takes off
Then dial in the weights
track top speed and how responsive on paper for each weight.
like this
6.5 grams top speed 60 kms doggy throttle
6 grams top speed 60 km revvy
5.5 grams top speed 58 km revvy

The belt may just need to wear in a little .
You could alos check belt travel by doing the sharpie test
Take a permanent marker and make a mark from the very inner edge of the variator to outer edge and then run down the road full blast and then measure how much marker is left.

The marker ideally for best take off would have have less than a mm of marker on the inner edge of the variator .
best top end would be 2-3 mm on the outeredge of the variator some of the aftermarket variators you can get down to less than mm
This is my variator after doing the test

[Zino]

Here is a better example this is a aftermarket variator with it properly shimmed to max out both top and bottom end by fully maxxing out variator from inner to outer edge

[Kagouras]

ok i stop comment on the other thread
thx,you cant imagine how much you re helping
just please answer about the derbi,sounds good deal to me

i have to wait some days for next modifications and i cant wait to get my hands dirty

[Zino]

The derbi gp1 is sharp looking scoot
I would re riding it home if they were available in the state