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Aero 125 variator tune-up
Posted: Fri Sep 14, 2012 1:30 am
by motormike
Having come to the point of replacing my drive belt, I have the variator disassembled and find the roller/weights are well worn.
Flat spots are numerous and distributed around each roller. None of them are dramatic, but it's time to replace them.
The Honda fiche offers only one choice, stock... 
Rollers are 20mm diameter, 15mm wide, 20 grams each.
I'm content to have new stock replacements, but...
Are there any aftermarket variators that fit Aero 125 ?
I would rather buy a Malossi unit if it exists, or crosses over from some other application.
Looking for any help you can offer, thanx in advance... 
Re: Aero 125 variator tune-up
Posted: Fri Sep 14, 2012 9:28 am
by Wheelman-111
Greetings:
I for one am interested in how Honda-san set up the Eighth-Liter Aero's CVT. Pics of the belt cavity and the various bits would interest me. With that much weight in the variator, it must be a pretty stout Contra spring?
Re: Aero 125 variator tune-up
Posted: Fri Sep 14, 2012 6:38 pm
by motormike
I'm not expecting to disassemble the clutch/driven pulley unit.
The contra spring is buried in there, right ?
Still in the learning curve here...
Not clear how the contra spring works and the difference it will make to change roller/slider weight.
Have located Dr Pulley sliders available in appropriate specs, but unsure about changing the weight/grams.
Claim by Dr Pulley is increased performance throughout the variator action, both take-off and top-end ?
Better take-off to drop to 19, 18, or what ?
Will gladly post pix when back at the bench. Computer compliance withstanding.... 
Re: Aero 125 variator tune-up
Posted: Fri Sep 14, 2012 7:21 pm
by LMH
I found dr pulleys sliders to be taller than stock rollers, also seems that if I was using a 8 g round that a 10g sliders was recommended, I took mine out after a couple unimpressed runs. No experience with them in the 125 yet.
Re: Aero 125 variator tune-up
Posted: Fri Sep 14, 2012 10:13 pm
by Wheelman-111
Greetings:
The contra spring is compressed betwixt the rear pulley sheaves. For a set of 20-gram weights to be needed, (Aero 50s use 10s) it must be pretty stiff. The spring stiffness in part determines how tightly the belt is gripped. Then it resists the upshift trend that the spinning Vario weights try to produce as the RPMs rise. There's probably an Integral Calculus formula dictating the shape of the vario ramp curves. Makes my head hurt. Balancing linear spring tension and exponential centrifugal roller force, dig?
Re: Aero 125 variator tune-up
Posted: Sat Sep 15, 2012 11:49 am
by DeathByFox
Go with the lighter ones first. You didnt find any aftermarket rollers in your size? Or maybe i missed that in your post. But id recomend a lighter roller. That way i can know what to put in my aero once i get it finalized!
Re: Aero 125 variator tune-up
Posted: Sat Sep 15, 2012 4:25 pm
by motormike
LoveMyHonda wrote:I found dr pulleys sliders to be taller than stock rollers, also seems that if I was using a 8 g round that a 10g sliders was recommended, I took mine out after a couple unimpressed runs. No experience with them in the 125 yet.
...okay, thanx for honest input...
Re: Aero 125 variator tune-up
Posted: Sat Sep 15, 2012 4:40 pm
by motormike
Re: Aero 125 variator tune-up
Posted: Sat Sep 15, 2012 7:56 pm
by motormike
Re: Aero 125 variator tune-up
Posted: Mon Sep 17, 2012 5:13 pm
by motormike
Ordered some Dr. Pulley Sliders today in 19 gram weight.
Should be here quickly and finding out did I do well, or am I just wagging my willie ? ?...
Re: Aero 125 variator tune-up
Posted: Tue Sep 18, 2012 6:31 am
by paulpauly7
it doesnt even look like the belt is rideing all the way up the pulley
Re: Aero 125 variator tune-up
Posted: Tue Sep 18, 2012 3:11 pm
by Tyler VR
I've played around a little bit with the variator rollers on my nh125. I'm using 15g rollers right now but thinking about going heavier to see if it will increase my top speed. I got mine from a ebay seller but he only has a few weights in the dimensions that we need.
My scooter was a slug trying to take off with stock 21g rollers, but they were worn so I don't know if they were functioning right. I'm thinking about getting a stock set of rollers on my next parts order just to see. With the 15g rollers it takes off fast, but I can't really say if my top speed is being limited by them. I think a good medium would be 18g rollers, that's what I'd like to try next.
I played around with a lathe and made my own rollers, but the dimensions were really hard to get perfect. I haven't tried them because I'm sure they'll rattle inside my variator. Maybe this winter I'll try to make my own again.
Let us know how the sliders work, I've been a little curious about those.
Re: Aero 125 variator tune-up
Posted: Tue Sep 18, 2012 7:50 pm
by motormike
paulpauly7 wrote:it doesnt even look like the belt is rideing all the way up the pulley
No, it looks like this new belt in slightly larger dimensions will have virgin... 
... pulley face to ride on....
Previous belt was taken off of an Elite 150 and was well worn at the time of interchange.
New belt is 799 x 19 x 28 compared to the stock size: 794 x 18 x 30.
Re: Aero 125 variator tune-up
Posted: Fri Sep 21, 2012 3:27 am
by motormike
motormike wrote:paulpauly7 wrote:it doesnt even look like the belt is rideing all the way up the pulley
No, it looks like this new belt in slightly larger dimensions will have virgin... ... pulley face to ride on....
Previous belt was taken off of an Elite 150 and was well worn at the time of interchange.
New belt is 799 x 19 x 28 compared to the stock size: 794 x 18 x 30.
Installed (dry) Dr Pulley sliders today, new belt, new rear tire, and new rear brake shoes.... 
Giving an accurate assessment of the change in performance based solely on the addition of sliders is not possible.
I changed too many things at once to be able to separate the differences.
Once I had everything buttoned up, Matt followed me on a shake-down run.
He reports a top speed of 64 mph on the first segment, then dropped back about the time I found just a pinch more.
I know that the new tire added some of the top speed and made the low end taller.
Maybe the belt being 1 mm wider than OEM has made the take-off feel a little slugish, relatively.
No question about the sliders having a totally different curve...higher rpm before the "squeeze" begins...then it feels like it climbs way harder through the mid-range.
Can't give numbers exact, but with stock rollers, it shifted at about 19-20 mph.
After that, it seemed to be all carb that took over.
The sliders "feel" like they start the shift process later, maybe 25ish, then stretch the next 25 mph out in a much better ratio than the rollers could.
To be sure, I'm a fan of the slider instantly. I am curious how the next lighter set would behave.
I betcha I would like it.... 
Sadly, I can feel some belt slippage on those WOT starts.
Not much, and not dramatic, just some obvious jutter in the chassis that I've felt before during belt destructions.
Chalk it up to a couple things: A. 5mm longer & B. 28 degrees( instead of 30)
I'm counting on it wearing in and settling down....shrug.. 
Enter the thought: Time to go with stiffer Contra spring....hummmmmmm
Probably buy an OEM belt next time i see one reasonably priced....
