Honda Vario 125 Takeoff shudder

[papa al]

The Lazada-ordered variator

arrived this afternoon.

~850baht delivered

+ tip of course.

Bought this schmancy protractor at

Thai Watasadu for B93.

 

Verified angles of 12.5º & 13.0.

Recruited a helper for stop watch trials.

Things are moving rapidly.

 

Edited December 28, 2021 by papa al

[VocalNeal]

On 12/28/2021 at 5:53 AM, Agusts said:

I use lighter rollers and have more acceleration now, but lost some top speed..., as expected.

Then you did something wrong. The CVT weights simply change the RPM at which the CVT ceases to act and the bike relies on engine power alone. So top speed will not be affected unless the weights are much too light.

Steady speed rpm does not alter that much with lighter weights. 

 

On 12/28/2021 at 2:41 AM, papa al said:

The 9-y/o Nouvo125 is like ...

 the doggiest.

I don't have any info on Yamaha as the variator I used to sell didn't have one for the Asian small Yamahas. I did buy some weights from Yamaha. From memory the 135 used 8.5g and the 125 8g. The nice thing about Yamaha is that the weight is written on the packet. 

 

9 year old may need a valve job and might also be running lower compression?

 

Modern Scoopy 110 is rated at almost 9hp so... 

[VocalNeal]

11 hours ago, U CNX said:

As the belt wears down, you can simply remove the washer between the bushing and the fixed half pulley to compensate for the wear  if it needed.

Or using your methods you could simply have added an extra washer rather than machining the pulley halves.????

 

Some aftermarket variators come with shims rather than washers for fine tuning. Piaggio MP3 guys have been adding fuzzy washers for years as their bikes are heavier and benefit from the slightly lower starting ratio. 

 

But it is fun to play.

Edited December 29, 2021 by VocalNeal

[VocalNeal]

 

I used to use one similar to this for my research.

[papa al]

Just back from time trials before and after variator mod.

No difference.

1000baht down the tubes.

[VocalNeal]

What did you buy? 

[papa al]

1 hour ago, VocalNeal said:

What did you buy? 

https://www.lazada.co.th/products/mio125nouvo-sxnouvo135-135125-i2135198830-s7156240348.html?&search=pdp_same_topselling?spm=a2o4m.pdp_revamp.recommendation_1.4.78b0274cROjc4X&mp=1&scm=1007.16389.126158.0&clickTrackInfo=cc31c361-c4e7-4280-86c4-a25e033a090e__2135198830__13204__trigger2i__224806__0.991__0.991__0.0__0.0__0.0__0.991__3__null__null__null__null__null__null____810.0__0.0__4.666666666666667__3__810.0__108012,110278,115402,119328,122209,122213,122584,122903,126918,127022,129114,129896,129993,129994,129996,130145,130147,131854,136964,136966,137075,137084,141200,141764,142007,142021,142134,149620__null__null__null__3650.16544_3650.16536_955.3632__null__13426__null__0.0__0.0________null__null

[VocalNeal]

We need to work on your weights. 

 

I can't see anywhere on the pictures what they gave you.

Put your OEM weights in an envelope and run to the post office and ask how much to post/mail. They will weigh them. Once we know that we can take the next step.

Did the new weights look to be the same size as the OEM ones. Ie. 20x12.

 

After you have checked the air filter????

 

If you look at the variator you bought you can see that the ends of the ramps have be "relieved" to allow the weights to travel further. So you could be set up for a possible higher top speed not acceleration.

Edited December 29, 2021 by VocalNeal

[papa al]

5 hours ago, VocalNeal said:

We need to work on your weights. 

 

I can't see anywhere on the pictures what they gave you.

Put your OEM weights in an envelope and run to the post office and ask how much to post/mail. They will weigh them. Once we know that we can take the next step.

Did the new weights look to be the same size as the OEM ones. Ie. 20x12.

 

After you have checked the air filter????

 

If you look at the variator you bought you can see that the ends of the ramps have be "relieved" to allow the weights to travel further. So you could be set up for a possible higher top speed not acceleration.

-Have scale from Lazada.

-Yes

-Not lately

[VocalNeal]

OK what do they weigh? 9grams or 8.5 or the like.

 

Conventional wisdom says use 85-90% of stock.

Edited December 29, 2021 by VocalNeal

[Agusts]

21 hours ago, VocalNeal said:

Then you did something wrong. The CVT weights simply change the RPM at which the CVT ceases to act and the bike relies on engine power alone. So top speed will not be affected unless the weights are much too light.

Steady speed rpm does not alter that much with lighter weights. 

 

I guess you're going by theory, in practice lighter rollers reduce top speed, I particularly know this about Forza, read and heard the same from numerous practical reports from others who tried it on Forza and some other scooters, and of course from my own experience... 

 

[VocalNeal]

3 hours ago, Agusts said:

I guess you're going by theory, in practice lighter rollers reduce top speed,

Actually no. 

 

In practise, if used correctly lighter weights do not lower top speed. If the weights are too light they may allow the engine to reach the rev limiter. If matched correctly to the peak HP then the scooter will reach its maximum potential.

 

Doesn't Forza come stock with a tachometer? Is nobody using it? BTW aftermarket exhaust seems to make more difference on a Forza but only about 3kph top speed. Seems Honda may have matched HP , gearing and aerodynamics to achieve maximum in stock form.

 

Take my Honda Zoomer. The rpm at steady speeds has not altered much even though I am using lighter weights. At 70 kph for instance they are almost identical. Hill climbing however is vastly improved. At maximum HP before it was doing 92kph. It still does 90 kph easily. I have not been bothered to hold it wide open on the highway to see what maximum actually is. I am not using the stock variator.

 

 

 

 According to my theory I should be using about 12g but I could only find an 11g and 14g versions of my chosen weights. I haven't yet created the 12g as 11 seems to more or less OK.

 

There is however value in understanding the theory before putting it into practise. 

 

 

Edited December 30, 2021 by VocalNeal

[papa al]

9 hours ago, VocalNeal said:

OK what do they weigh? 9grams or 8.5 or the like.

 

Conventional wisdom says use 85-90% of stock.

10

[papa al]

48 minutes ago, papa al said:

10

Was hoping to find improved acceleration by

change of variator angle only.

But not there.

[VocalNeal]

How far down the rabbit hole so you wish to go?

I believe you need 8.5g but Lazada only has weights in 1g increments. So say 9g is closest but 8 might work also but you would have to change twice? 

I have bought some 8.5 weights from yamaha but not sure if they were for Nuovo135 or GT125 and were 20x12 If there is a Yamaha dealer near you and they are friendly and cooperative.

 

Daniel from Taiwan will sell you some Dr. Pulley 8.5, I think about $22 a set plus shipping. TechPulley Malaysia will sell you set of theirs for $28 including EMS.

 

Sent you a PM.

[papa al]

50 minutes ago, VocalNeal said:

How far down the rabbit hole so you wish to go?

I believe you need 8.5g but Lazada only has weights in 1g increments. So say 9g is closest but 8 might work also but you would have to change twice? 

I have bought some 8.5 weights from yamaha but not sure if they were for Nuovo135 or GT125 and were 20x12 If there is a Yamaha dealer near you and they are friendly and cooperative.

 

Daniel from Taiwan will sell you some Dr. Pulley 8.5, I think about $22 a set plus shipping. TechPulley Malaysia will sell you set of theirs for $28 including EMS.

 

Sent you a PM.

Will just take to papa's regular shop.

They have everything in stock

and are very quick & good & cheap.

Maybe do that right now.

[papa al]

Ok.

Changed out for 8g. rollers.

160B & 100B labor

+ tip.

Seems better/louder/higher revving.

?

Will √ vs. clock later.

Edited December 30, 2021 by papa al

[seedy]

3 hours ago, VocalNeal said:

How far down the rabbit hole so you wish to go?

I believe you need 8.5g but Lazada only has weights in 1g increments. So say 9g is closest but 8 might work also but you would have to change twice? 

I have bought some 8.5 weights from yamaha but not sure if they were for Nuovo135 or GT125 and were 20x12 If there is a Yamaha dealer near you and they are friendly and cooperative.

 

Daniel from Taiwan will sell you some Dr. Pulley 8.5, I think about $22 a set plus shipping. TechPulley Malaysia will sell you set of theirs for $28 including EMS.

 

Sent you a PM.

What will you benefit from all the work changing angles, adjusting weights, etc. in the real world ?

Will it accelerate noticeably quicker ? Or if you go the other way will it increase top speed ?

Never experimented on a motorcycle so curious.

In my snowmobile days had a modified 400cc Mercury. After a few changes, and studded track for ice work, it would pull the front skis a good 2 feet when you walked on it.

[U CNX]

On 29.12.2021 at 08:11, VocalNeal said:

Or using your methods you could simply have added an extra washer rather than machining the pulley halves.????

You forgot about the changed  half-pulley angles, this is important. ????????

 

With the changed angles of the half-pulleys, the belt is pushed out to the outer radius more slowly.

Edited December 30, 2021 by U CNX
correction

[papa al]

36 minutes ago, U CNX said:

You forgot about the changed  half-pulley angles, this is important. ????????

 

With the changed angles of the half-pulleys, the belt is pushed out to the outer radius more slowly.

Did not make a difference w/ papa's YNSX.

Just as slow.

[U CNX]

On 12/29/2021 at 11:23 AM, papa al said:

Just back from time trials before and after variator mod.

No difference.

Mech replaced the half-pulleys only? 
Was the torque driver disassembled with cleaning and put new grease?
Torque driver running affects acceleration too.
I am confused very low roller weight  relative to the standard for a noticeable increase acceleration.

I would change the belt for a new one when working with the CVT.

[U CNX]

4 minutes ago, papa al said:

Did not make a difference w/ papa's YNSX.

Just as slow.

First time in my life, when changing the angle of half-pulleys acceleration does not change explicitly.

When adjusting CVT, I always use a tachometer to be sure of the result.

[papa al]

20 minutes ago, U CNX said:

-Mech replaced the half-pulleys only? 
-Was the torque driver disassembled with cleaning and put new grease?
Torque driver running affects acceleration too.
-I am confused very low roller weight  relative to the standard for a noticeable increase acceleration.

-I would change the belt for a new one when working with the CVT.

-replaced all this. [Lazada photo]

-What the heck is a torque driver.?

- 10g original; 10g 2nd configuration; 8g now.

-Didn't change belt.

It looked fine.

Didn't want to change more than one variable at a time.

Science.

 

[papa al]

24 minutes ago, U CNX said:

When adjusting CVT, I always use a tachometer to be sure of the result.

5 5

[papa al]

Original pulley halves:

14º/15º, measured.

Edited December 30, 2021 by papa al

[VocalNeal]

 

10 hours ago, U CNX said:

Torque driver running affects acceleration too.

The torque tube as its name suggests reacts to engine torque and attempts to squeeze the driven pulley (clutch end) together. This forces the drive pulley, front, apart and thus causes the gear ratio to change. This is how the transmission "changes down" when going uphill and applying more throttle and is especially noticeable two-up. Increasing the spring rate reduces this change down effect. I am not aware that the torque tube plays any role in acceleration as during that phase it is already subject to maximum torque and at standstill the pulley halves are already tight together.

Changing the spring rate has the effect of tightening up the transmission. I.e. keeping the transmission in lower gear. This has to be matched by installing heavier weights, Keeping the transmission in its lowest gear doesn't necessarily allow the system to "relax" or change up at low load/torque cruising.

 

10 hours ago, U CNX said:

I am confused very low roller weight  relative to the standard for a noticeable increase acceleration.

The weights are the heart of the system. The centrifugal  force produced by the weights moving along the "ramps" causes the pulley halves to separate changing the diameter of the contact point of the belt, this changing the ratio. As the centrifugal force has an RPM component if the weights are lighter then the RPM needs to be greater to provide the equivalent force. So the engine needs to rev higher to provide the same centrifugal force. 

As most scooters don't reach anywhere near maximum torque during acceleration, say 5350 rpm, fitting lighter weights allows the engine to generate a greater torque at 6500 rpm. Which is the stated maximum torque rpm for the subject engine.

It is torque which moves the scooter forward so the greater the torque the greater the acceleration.

 

It is of course a balancing act to match weights to engine characteristics. Best thing to do first is to fit a tachometer to see what is actually happening.

 

[VocalNeal]

18 hours ago, seedy said:

Will it accelerate noticeably quicker ? Or if you go the other way will it increase top speed ?

YES better acceleration up to the point where the road speed catches up to the transmission, say 70-75 kph for my Zoomer,  from then on it is just engine power.(sic).

 

Top speed is a factor of engine power, gearing and aerodynamics. Aerodynamics less so obviously at lower speeds. Once the weights have forced the pulleys to their maximum travel the gear ratio is set and from then on it is engine power and rpm. Some scooters have space in the crankcase for a larger front pulley so gearing can be raised a tad. But this won't effect top speed if the engine can provide the power. The gearing also can't be raised much as even with a larger front pulley the belt length is fixed so to enable to belt to travel around the larger diameter it needs to stretch. This causes extra stress, friction etc. which absorbs engine power.

You might get 10% ( PCX/Click125)

[seedy]

Thanks

[VocalNeal]

On 12/30/2021 at 11:19 PM, papa al said:

-replaced all this. [Lazada photo]

-What the heck is a torque driver.?

- 10g original; 10g 2nd configuration; 8g now.

-Didn't change belt.

It looked fine.

Didn't want to change more than one variable at a time.

Science.

 

And?

[papa al]

6 hours ago, VocalNeal said:

And?

Yea running stronger.

Will quantify sometime.