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YAMAHA ZUMA 50 - Top Speed (BBK to Gears) w Stock Muffler
http://www.zumaforums.net/phpBB3/viewtopic.php?f=23&t=27997
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Author:  specalk [ Mon May 28, 2018 8:45 pm ]
Post subject:  Re: Yamaha Zuma - Top Speed (BBK to Gears) w Stock Muffler

Nice info

Author:  willie634 [ Sat Jun 09, 2018 4:07 pm ]
Post subject:  Re: Yamaha Zuma - Top Speed (BBK to Gears) w Stock Muffler

Had to change head gastket, cause i overheated from 84 jet. Installed oversize blower, that sure helps alot.

I installed the Pollini hi-speed variator and long belt which i havnt tested much, but also havnt noticed much of a difference with. Dissapointed the variator only came with half assembly. wth

I installed 88MJ and removed snorkel... ok, but not overly impressed. The tailpipe hole is sure small and def restricting, seems like theres no point getting bigger jets at this point while the muffle only lets through so much air

Speed is still in the 70+KM/hr range and needs a bit more.. Also havnt tuned weights, but they are close

____________________________________________________

I am going to try returning the 15/50 gears back to the orignial, put snorkel back in (lots of rain here). and finish 88MJ tuning, lower needle.


OR

This would be my alternative choice next
https://www.scootertuning.ca/en/exhaust-systems-50cc-70cc/3000146-exhaust-silent-sport-70cc-minarelli-horizontal.html




... seems i would be happy with stock gearing and have this be over with

Author:  willie634 [ Mon Jun 11, 2018 12:54 pm ]
Post subject:  Re: Yamaha Zuma - Top Speed (BBK to Gears) w Stock Muffler

Scooter Gearbox and Basic Gear Theory
https://youtu.be/gV47Jv1hfy0

Author:  willie634 [ Tue Jun 12, 2018 10:43 am ]
Post subject:  Re: Yamaha Zuma - Top Speed (BBK to Gears) w Stock Muffler

SCrew it, I just ordered this muffler, i want to be done with carb tuning.
https://www.scootertuning.ca/en/exhaust-systems-50cc-70cc/3000146-exhaust-silent-sport-70cc-minarelli-horizontal.html

I hope i didn't make a mistake returning the gear back to stock, but perhaps the new variator and long belt will compensate. Will decide on gears once carb tuning is dane

Author:  RookieRecurve [ Thu Jun 14, 2018 10:13 am ]
Post subject:  Re: Yamaha Zuma - Top Speed (BBK to Gears) w Stock Muffler

Cool. I am curious to hear how this muffler performs along with your other tuning. I am going to install a larger fan as well since I recently swapped out a Stage 6 aluminum cylinder for a TP cast one. I need to trim some plastic off of the fan housing first to make it fit though...

Author:  willie634 [ Wed Jun 20, 2018 11:40 am ]
Post subject:  Re: Yamaha Zuma - Top Speed (BBK to Gears) w Stock Muffler

RookieRecurve wrote:
Cool. I am curious to hear how this muffler performs along with your other tuning. I am going to install a larger fan as well since I recently swapped out a Stage 6 aluminum cylinder for a TP cast one. I need to trim some plastic off of the fan housing first to make it fit though...


They fooled me with the picture of that muffler, the output pipe has a smaller pipe inside of it, almost same size as stock, maybe 1-2 mm bigger. Also i had to file potruding metal burrs on face that rests against jug. The metal heat plate looks a little cheap...

I did like that it has the catalytic converter on it, plus my old muffle was a pile of rust. My guess is that its mild increase but somthing, perhaps that is all that can be expected from the stock style muffler

I was about to tune and forgot to tighten spark plug and need to order new gasket set again :doh: Picked up a 90 jet as well from yamahA, im going to start there next time...

Author:  willie634 [ Thu Jan 10, 2019 7:17 pm ]
Post subject:  Re: YAMAHA ZUMA 50 - Top Speed (BBK to Gears) w Stock Muffle

Finally Got bike close to tuned in with an 88 Jet.

I was glad to find this thread stating that the polini Variator is a waiste of time.. I never changed the clutch springs it has no takeoff.
http://www.zumaforums.net/phpBB3/viewtopic.php?f=54&t=13835



I think this thread is Basically a Fail... Wanting to buy a Sport muffler now. More info to come...

Author:  zino18 [ Fri Jan 11, 2019 7:01 am ]
Post subject:  Re: YAMAHA ZUMA 50 - Top Speed (BBK to Gears) w Stock Muffle

I ordered the same polini variator and polini clutch
I have a lot lighter weights than stock I plan on tuning with 4.7 ,5.1, 5.7 ,6.9 grams
I wont be able to slap it on until the snow goes away and I add the malossi bbk gears and pipe .

I have a street pipe malossi wild lion it added a 2 mph top end and added to take off For a basic bolt on with no cvt tuning just a carb upjet I was very happy with .
That Street Pipe on ScooterTUning always on sale price suggested they are trying to unload them.
I am swapping the wild lions to my vino's.
I wont be adding bbk's or gears to those anytime soon those scoots are more for my wife and daughter
I will be trying a technigas next r on the zuma.
My top speed with just exhaust and Carb Upjet is 43 on flats no wind
Looking to break 50 again

Author:  willie634 [ Fri Jan 11, 2019 7:49 pm ]
Post subject:  Re: YAMAHA ZUMA 50 - Top Speed (BBK to Gears) w Stock Muffle

I put the 15/50 gears back on and it goes waaay Faster...

Seems like the lesson here is the Gearbox is the key to more top end if you bike can push the gears.... Bike is not as fast as i Want. So i May attempt a sport muffler and even faster gears one day...

Black trophy 70cc with 88 M.Jet at sea level pushes the 15/50 gear no problem and almost makes me wonder if it could push faster gears just on its own. People say that it wont but....

Author:  zino18 [ Sat Jan 12, 2019 8:46 am ]
Post subject:  Re: YAMAHA ZUMA 50 - Top Speed (BBK to Gears) w Stock Muffle

What is your top speed now ?
I have the 14/42 gears so they provide the same final ratio as you 11 to 1 once i put them in .
The exhaust would help it will move your rpm's up you will need lighter weights to fully enjoy it and possibly stifffer clutch springs so it is not a dog off the line .
The technigas next r I bough of scootertuning was fully derestricted already .
So i will dial that in with the new gears and share my results so you can see how wild you want to go on a pipe .

Author:  willie634 [ Sun Jan 13, 2019 7:00 pm ]
Post subject:  Re: YAMAHA ZUMA 50 - Top Speed (BBK to Gears) w Stock Muffle

Too many hills here to know my top speed. But a Very noticeable 6+kmph From changing the gears.

I have Stock weights(6.5g?), 7.5g and 8.5g weights. They All are giving about the same performance.

Any guidance on the weights?. I Left the 7.5g In.

Author:  willie634 [ Mon Jan 14, 2019 12:56 pm ]
Post subject:  Re: YAMAHA ZUMA 50 - Top Speed (BBK to Gears) w Stock Muffle

How to change Gears / Steps for changing gears

-Remove GearBox/tranmission Screws.
-Hold the rear brake, and then loosen Rear Tire Nut (24mm) until it is flush with the Bolt.
-Tap the tire Axle Bolt with a hammer until the gearbox plate pops off.

That plate cover Has the Clutch shaft going threw it. This shaft gets changed. And comes off Fairly easy.
-Use a padded vice and Sockets to hammer with.
-When hammering the new shaft in, be sure to cover the inside of plate with clean paper towels so no crap falls in..


Next is to change the Gears in the center... The gear on the very right side comes right off allowing you to pull out the center gears.
-Put the gears on a padded vice and find a socket that fits on the end to hammer onto.
-Use a torch to heat the outside gear for 1-3 min depending on flame. You may have to wait a little for metal to expand.
-Once removed, place the center gear shaft into the freezer and wait 15min or so.
-Flame the new outside gear to hear it up.
-Remove center gear from freezer and hammer it is.

Voila...

-I had to put a new Gasket as original one was leaking. Even with new gasket i had to overtighten from specified torque. So perhaps overtighten original gasket would be enough.

*Fill the Gearbox with 110g/ml if it is still wet OR with 130g/ml If it was cleaned dry with recommended Gear oil (mine is 80W 90)

*Dont forget to re-tighten your back tire Nut!!

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