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General => Technical | How To => Topic started by: Vintage MX on March 18, 2014, 01:21:46 PM

Title: Top Speed and After Market Variator Swap, 50cc
Post by: Vintage MX on March 18, 2014, 01:21:46 PM
2012 Like 50 2T, 400 Miles

The bike has the following mods:

Technigas Silent Pro
Correct jetting for 2700 feet
38mm shoulderless variator bushing
1000 RPM clutch torque spring
36 mph with a 5' 11" 215 pound rider

Just added the torque spring.  Did not increase top speed but did make the transition to "top gear" more linear.

Here's the Question: With this setup, is there any top speed benefit to installing a Malossi variator?

Thanks for your help.

Tom
Title: Re: Top Speed and After Market Variator Swap, 50cc
Post by: JJJoseph on March 29, 2014, 05:27:23 AM
The variator might give you a few extra knots if it's a larger diameter than stock, but the gain won't be spectacular.  Your best speed increase, of the order of 10mph or more, will be from a 70cc+ BB kit plus lower (numerical) ratio reduction gear set like 8:1.  With a 4T, 50mph in still wind conditions is possible with WOT; with a 2T 60mph is reachable.
Title: Re: Top Speed and After Market Variator Swap, 50cc
Post by: Vintage MX on March 29, 2014, 09:40:43 PM
Thank you for your insights.  Took an 80 mile ride today.  Cruised easily at 36 mph.  Saw 40 mph with a tail wind.
Title: Re: Top Speed and After Market Variator Swap, 50cc
Post by: Stig / Major Tom on March 31, 2014, 02:54:20 PM
Thank you for your insights.  Took an 80 mile ride today.  Cruised easily at 36 mph.  Saw 40 mph with a tail wind.
"Cruised at 36MPH".......but how long will a scooter last being driven with the throttle pegged? How long will any engine last doing that? 80 miles at 36mph is close to 2 1/2 hours with the throttle pegged wide open. I hope these 50cc Scoots are de-tuned to handle that ?
On another matter - I see some of the 50cc LIKE's with so many mods...I wonder if that same $$ could have purchased the LIKE 200i - instead of the 50?
Title: Re: Top Speed and After Market Variator Swap, 50cc
Post by: Vintage MX on April 04, 2014, 03:08:21 AM
You are probably right on all counts, but I did find it would run about the same speed at 3/4 throttle or wide open.  In the 70s, I raced a 125 cc motocross bike that needed a tear down about every 15 to 20 hours of wide open running.  I trust the full synthetic oil I am using today, along with the lower top revs will prolong the life a bit more than that.  If not, top end rebuilds are easy and relatively cheap.  I got the scooter for exploring the lonely back roads of the great Southwest.  Had my time on the big bikes and thought the 50 would keep me from being tempted to ride at high speeds and in traffic.  So far, it has been great at that!  Ride safely, my friend.
Title: Re: Top Speed and After Market Variator Swap, 50cc
Post by: naughty lee on April 06, 2014, 12:20:32 PM
Big bore kits are not always the answer. Have a look in my zx50 thread. Ink your current variator and follow the instructions. Odds are, if you shorten your drive boss, it ll go faster.
Title: Re: Top Speed and After Market Variator Swap, 50cc
Post by: 245luigi on April 06, 2014, 08:48:48 PM
Now what would happen if we put on a BBK, upgeared then shortened the variator bushing?? MUAHAHAHA

Lightspeed, Chewie!
Title: Re: Top Speed and After Market Variator Swap, 50cc
Post by: wkreps on April 07, 2014, 11:43:58 PM
When you talk about shortening the variator bushing, do you mean go out and buy a shorter one or machining it down? If buying, are you just taking measurements with a micrometer and buying shorter?
Title: Re: Top Speed and After Market Variator Swap, 50cc
Post by: blue on April 08, 2014, 02:24:40 AM
Now what would happen if we put on a BBK, upgeared then shortened the variator bushing?? MUAHAHAHA

Lightspeed, Chewie!

Be carefull shorting your variator.I did mine like 3mm shorter and I got to close to the starter bendex with the belt and broke a few starter bendex and belts. its better to play with the weights and find the best one to work in your scoot.
Title: Re: Top Speed and After Market Variator Swap, 50cc
Post by: 245luigi on April 08, 2014, 12:22:21 PM
Im talking machining the variator bushing to a shorter length. Check out "naughty lee" on the forum. He has a good write up and addresses the problems blue brought up
Title: Re: Top Speed and After Market Variator Swap, 50cc
Post by: Vintage MX on April 09, 2014, 02:46:20 PM
I did shorten my 38mm bushing without a shank (the normal one swapped in to de-restrict) to 36mm but did not notice any top speed gains.  But hey, at 220 pounds, there may not be much that will help with a stock engine and Technigas Silent Sport pipe.  :-)
Title: Re: Top Speed and After Market Variator Swap, 50cc
Post by: 245luigi on April 09, 2014, 03:15:58 PM
Well thats a bummer! I just found out that a friend of a friend has a machine shop in his basement. When the Malossi Variator comes in ill have 2 vari bushings (Stock and the one that came with Naraku). I think ill experiment :)
Title: Re: Top Speed and After Market Variator Swap, 50cc
Post by: blue on April 14, 2014, 12:49:34 PM
Have you tried raiseing the needle in the carb I would think your scoot would do 40 to 45 easy.
Title: Re: Top Speed and After Market Variator Swap, 50cc
Post by: naughty lee on April 16, 2014, 01:58:38 PM
Machine the boss down, one mil at a time and then reassemble. Using a sharpie pen, ink the inner variator so that once it's been reassembled and run up, you can see how high the belt is going up the variator (effectively making it a higher "cog" on the front) this will increase the gearing at the front.
He aim of he game is to have the belt ride right up to the top of the front variator at max revs.
If you accidentally take a little bit too much off making the outer variator strike the starter bendix (and don't have a spare boss) you can fit a small washer at the very back of the drive shaft behind the inner variator to give you some clearance.
This should only be a short term fix though as it will put your belt a tiny bit out of alignment.
Machine down in small amounts!
When it's near perfect, the outer variator will "chink" occasionally against the starter bendix when on the side stand but not when the bike is parked on centre stand.
Good luck !
Title: Re: Top Speed and After Market Variator Swap, 50cc
Post by: zombie on April 18, 2014, 02:32:52 AM
Every bit of advice is spot on. I only have 3 items to add. Is it the Factory original belt? Does it say Bando on it?
Secondly, I have to be delicate here... 215lbs is pushing it pal. 40MPH flats is about 3.5hp can handle. That's with fresh oil/fuel, properly inflated tires, correct belt, and optimum tuning.

I would get the Jasil/Top Racing Var. instead. Better ramp angles, and a chromium face that way outlasts Malossi. 3-5 MPH better than Malossi too