Track T-800cdi on the bench.

[BertTrack]

After the calculations and discussions. It was time to put the Track on the dyno to confirm or refute the calculations.

The result is here. http://www.youtube.com/watch?v=ArPJsF3BPvc

Conclusion is the gearing is way too long.

We tried a smaller tire and got lower r.p.m. on the engine for the same speed. Much smoother start (on the road, lower r.p.m's needed to get moving) And best of all the same hp on the rear wheel. All i get to give up for this is not having a theoretical top speed of 240+km/hr

I wasn't interested in that anyway.

[coachgeo]

What tuning if any have you done with the CVTech clutch(s)? Spring or weight changes orrr?

[BertTrack]

The whole driveline is stock including the cvt. Unfortunatly the rear gear hub is geared to be able to reach 240+km/hr Stock bmw 2.54 gear ratio but in the bmw cruiser it was used with a 15 inch wheel.

The track has a 17 inch wheel.

[coachgeo]

The whole driveline is stock including the cvt. Unfortunatly the rear gear hub is geared to be able to reach 240+km/hr Stock bmw 2.54 gear ratio but in the bmw cruiser it was used with a 15 inch wheel.

The track has a 17 inch wheel.

True you can't change the ratio's with a typical design shaft drive except by changing tire size. Unless of course your not getting full use of the CVT's ratio.

Does the belt drop and rise the full spectrum from top to bottom on each of your clutches? Have read where this can be measured by colouring a wide stripe on a sheave of the clutches with a marker of some type. Run her a while and then look to see how much of the line is left to indicate how far up the sheaves your belt is travailing.

[BertTrack]

It's even simpler with the Track.

It's easy to make it hit the rev limiter. And does that around 140 to 170km/hr. Depending on the bike involved. (on the road)

During the test, the end speed where the mechanic decided it was enough it was doing 240km/hr on the rearwheel (still needing 25hp for that(rev limited). And still i saw the cvt shift up a little when he throttled off. So even at those speeds it has some room.

I won't be setting it so that it comes to the cvt end. Because there needs to be belt pressure still. Even when the belt is worn a bit. Still as we tried with the smaller diameter rear tire getting 10% circumference off already makes a big difference in pick-up. And results in lower engine rpm @ constant speed.

I'm considering getting a 3 ratio gear for the wheel. It's about 18% shorter than current.

I don't know if it's available but i'll have it made if need be.

The engine doesn't have the power for 200km/hr so i'm not worried about ever reaching that limit. But i do want it to behave much easier at low speeds and have lower rpm's when cruising.

[coachgeo]

Now that you've eye balled the CVT so many times; you think you could identify which CVTech clutches are on it. Go to below page. Click on "our Products" and thumb thru the Drive and Driven Pully PDF's with pictures to identify them. Only about 4 models of each so should only take a few moments

http://www.cvtech-ibc.com/?p=1.73522222042084

[coachgeo]

... Unfortunatly the rear gear hub is geared to be able to reach 240+km/hr Stock bmw 2.54 gear ratio but in the bmw cruiser it was used with a 15 inch wheel.....

Have you been able to discern what modifications if any are done to that BMW final drive to get it mounted to the Track......... or is it just the gears from BMW and the whole final drive housing is custom built for Track?

[BertTrack]

It's the Trailbloc and the Invance LV.

Mods: The rear housing has had the joint and parallel lever housing added.

[coachgeo]

It's the Trailbloc and the Invance LV.

Mods: The rear housing has had the joint and parallel lever housing added.

Trailbloc is listed to be for city cars hmmmmmmmmm. Does the Bike incorporate the engine braking systems that can be part of the Trailbloc clutch and Invance LV?

As to the BMW final; when you get a chance would love a pic pointing out the joint and parallel lever housing addition for those of us; like me, who do not know what the stock BMW looks like before the modifications.

I apologize for hijacking your thread and GREATLY appreciate the info. you've relayed.

[BertTrack]

No problem.

in this video http://www.youtube.com/my_videos_annota ... ature=mhsn

At 11 seconds you see it in front of the silver gear housing. That black vertical bit has been added. It incorporates the joint and link connection for the parallel bar. 17 seconds it's more clearly visible.

If you look at a BMW cruiser picture you will see it originally has no joint in the back but it has that silver housing.


As for the engine breaking. It's keeping the engine on around 2000rpm when breaking on the engine.

I think the only part that is needed to get that function from the cvt is a different shape helix part on the secondary. Making it a corkscrew shape and not a V so when accelerating or decelerating the secondary increases the spring tension. But because the engine breaking power is so little compared to engine power the downshift is much weaker when breaking on the engine. This could probably be fixed by using a different angle for the brake part of the cvt helix. But i have to look into that further when i get around to it. (If i get to it)

[coachgeo]

No problem.

in this video http://www.youtube.com/my_videos_annota ... ature=mhsn...

Bad link

Good link: http://www.youtube.com/watch?v=bqpA3bt9GFY

thanx

[coachgeo]

Wait...... that is a right side final drive........ sooooooo that is why the engine is mounted backward putting the CVT on the typical fan end of the crankshaft. To get engine's rotation to match the CW rotation of BMW's final drive.

Or am I missing something.

NOTE: error in this post!! see my post just below

[BertTrack]

I don't know about that.

The front would hold the pulley normally.
The back is the clutch housing etc normally. Of course in a smart car it's mounted sideways.

[coachgeo]

Wait...... that is a right side final drive........ sooooooo that is why the engine is mounted backward putting the CVT on the typical fan end of the crankshaft. To get engine's rotation to match the CW rotation of BMW's final drive...

...The front would hold the pulley normally. The back is the clutch housing etc normally....

woops......... I remembered rotation of Final Drives wrong; so ignore my ccw/cw backward engine ramble. Right side Final drives ARE CCW not CW.

(see: viewtopic.php?f=41&t=2479 )

[BertTrack]

As a result of the test:

Ratio final drive increased to 3.0

Giving more rpm's to the drive-shaft.

Results:
Running steady and a quick look at the seal I've changed. From inner-tube to proper seal used in front wheel drive cars.http://youtu.be/N2UgLzb14QE
Having a go at a 0 to 100km/hr run. Mind you it's a slow roll on.http://youtu.be/V2_zPc4cPCI

[coachgeo]

As a result of the test:

Ratio final drive increased to 3.0

Giving more rpm's to the drive-shaft.

Results:
Running steady and a quick look at the seal I've changed. From inner-tube to proper seal used in front wheel drive cars.http://youtu.be/N2UgLzb14QE
Having a go at a 0 to 100km/hr run. Mind you it's a slow roll on.http://youtu.be/V2_zPc4cPCI

got a part number for that FWD seal? Others may find it useful swap.

So w/out comparision in the video for us to draw our own conclusions.........what differences are you finding w/that ratio that you like and/or do not like?

[BertTrack]

The seal is a universal seal. They had laying around in the car shop. It's a one size fits all type of thing. Stretches really well. If you put all your weight into it.

As for the comparison. I'm working on it. But it's busy times here. There will soon be a rough movie on youtube. The first ride with the 3.0 ratio.

My experience so far is that it pulls much better from 0. And is able to accelerate decently even at low rpm's compared to before. The "oh my, am i trying to pull a trailer?" feeling is gone. Blip it over 1150 and it goes.
Also it's stable 2200 to 3200 rpm speeds is much wider. Meaning i can now cover 40 to 120km/hr with that rpm range. This should make it more fuel efficient.

And when i open up it's able to transfer more power thanks to the higher secondairy rpm. I feel it's eager to get going now. Really pulls. I would like to try the other ramps though so it's not as eager to gear down.

Once i'm back from a good cause event next week i'll try to match up some old movies to match and compare. Though ofcourse at that time i didn't have a rpm gauge.

I think this is how the cvt should work. With possibly a little less downshift when hitting the throttle.

[BertTrack]

I've had a chance to compare it to another Track on the road.

At low speeds my track is running 100 to 300 rpm higher.
At 70km/hr i saw 150rpm less on a flat stretch.

It's hard to compare both tracks as we weren't loaded the same, don't know really in what way our cvt differs when it comes to setup.

But what is sure is that i'm not seeing a 20% increase in rpm over the whole board. It varies between 5 to 10% max and top speed wise i'm still able to do 150+km/hr.

[BertTrack]

http://youtu.be/6xqFazUSWxU

Get's interesting c.v.t. wise @ 50 mins in.

That's the first ride with the 3 ratio and 2 grams added per weight in the primary c.v.t. after the broken helix event.

After changing the final drive ratio to a 3.0 from a 2.54, the secondairy cvt is spinning faster now and the torque load on it has decreased. Pick up was much better after that alone. For the 20% increase in secondairy r.p.m. i didn't get 20% more r.p.m. on the engine back thanks to the torque feedback of the Invance LV.

To enable lower r.p.m. on the engine i increased the weights in the primairy with 2 grams each approximately. (After the Big Knock)

As the weights travel outward one side of weight get's deflected more and more. The angle changes and the impact of the weight is reduced. Giving in effect not as much higher gear at highers speeds as i would like. But probably that's just as well since at those speeds I'm pushing higher power through. So i won't change that.

The snap/clunk that is still noticeable when you go off the throttle and then on again with the secondairy c.v.t. in it's low gear position is caused by the long travel of the guide wheels and the stop on one of the helix sides. What happens is you open up and yank one side of the sec. c.v.t. to the opposite position. It has not yet been pulled into the helix (higher gear). Makes me wonder why that non helix area is there in the first place. This may still be an issue to look at. As it shouldn't be too hard to add an angle on the helix part where it slams into.
Also when braking on the engine it will disengage when the guide rolls exit the helix and enter that flat area.

I am happy with how it rides now. Time to get the electronics to charge well. On to the next project!

[henneberg]

Would the Track has been become too long in the first place, in case an BMW gearbox had been used ?

[BertTrack]

I think that could be calculated using wheel circumference, final drive ratio, top gear ratio of the specific bmw gearbox.

The reason why i had to change mine was because with the 2.54 ratio it was setup to reach a top speed of over 240km/hr. But i only have 45hp. So that's not even close to a nice match. It was preventing good rpm of the sec. c.v.t. (they used a 15 inch wheel geared rearhub and installed a 17 inch wheel on it)

I think that with a Diesel having less power than a BMW boxer (hp) but also lower rpm, it shouldn't be too far off. Aslong as you don't go mixing up rearhub and different size wheel.

Oh to get to the point. Yes it would have become too long if only because they used the 17 inch wheel on the 15inch wheel geared hub. That alone makes it 20 to 30% longer. Which could be good if you can actually make enough power at those low rpm's to reach the speed. (which wasn't possible in my case)

[coachgeo]

http://youtu.be/6xqFazUSWxU

....That's the first ride with the 3 ratio and 2 grams added per weight in the primary c.v.t. after the broken helix event....

To enable lower r.p.m. on the engine i increased the weights in the primairy with 2 grams each approximately. (After the Big Knock)

As the weights travel outward one side of weight get's deflected more and more. The angle changes and the impact of the weight is reduced. Giving in effect not as much higher gear at highers speeds as i would like. But probably that's just as well since at those speeds I'm pushing higher power through. So i won't change that.

The snap/clunk that is still noticeable when you go off the throttle and then on again with the secondairy c.v.t. in it's low gear position is caused by the long travel of the guide wheels and the stop on one of the helix sides. What happens is you open up and yank one side of the sec. c.v.t. to the opposite position. It has not yet been pulled into the helix (higher gear). Makes me wonder why that non helix area is there in the first place. This may still be an issue to look at. As it shouldn't be too hard to add an angle on the helix part where it slams into.
Also when braking on the engine it will disengage when the guide rolls exit the helix and enter that flat area.

I am happy with how it rides now. Time to get the electronics to charge well. On to the next project!

Must of missed the note on here of your helix breaking; or my feeble head just forgot. Can you point me to a discussion on that. Curious to your thoughts why/how it broke.

All the CVT's manufactured are made with a generic helix angle for a broad set of applications. Unlike auto's etc. they don't make each piece rather specific to that auto buttt.. over time it's kinda user friendly to make modifications to things like you have to fit the riders preferred seat of the pant's feel. As each rider does that... others can copy rather inexpensively compared to trying change to new gear ratios inside a transmission, or swapping out to a whole different ratio tranny etc.

Did you answer your own question why the flat section of the helix is there? "when braking on the engine it will disengage when the guide rolls exit the helix and enter that flat area." Or I miss understood you.

MUCHO THANX for your updates. It's a good education for all of us considering CVT use.

[BertTrack]

@ coachgeo: There wasn't a discussion on it. When i was back from the big knock i heared a clunk inside the cvt. I opened it up and one of the bigger helix parts had come loose. Bolt came straight out and hit the other helix part. All other 3 bolts were "crack" tight still so i guess it's vibrations that shook the 4th loose. I can't think of any other reason. It's not a bolt that transfers power. Just keeps it in place when there is no pressure on it from the little wheel on the other cvt sheave. So the next set i put together with loctite 248.

It was still ridable since the helix couldn't get out and was locked in place thanks to the roller (little wheel). But when you push the track backwards that part of the helix will not have pressure and thus came loose. Small problem easily fixed.

Oh! so the one helix broke thanks to contact with the flying bolt. And the other got a filler area broken off. (causing it to clunk clunk)

I feel like i've gotten a little further. I can now explain why the sec. c.v.t. snaps sometimes when you go on power after breaking on the engine to below disengagement speed. That is definitely the roller that was previously at rest point from engine breaking, which then get's yanked against the flat piece of the helix at low speed. This had led to roller breaks/flying off. Could actually see the rollers were taking a beating. Loosening up slowly over time because of the pressures involved.

That's about as far as i can go at the moment. I've noticed some inconsistencies in my previous assumptions about that helix function. It actually works as i expect it to work. But i can't yet explain it. Beyond a doubt.

But here goes as far as i have observed.

The sec c.v.t. has 2 sheaves. Front sheave connected to the rollers. The rollers can move axially "in" the helix. Rest position for this is sheaves together, rollers are on the rear side of the helix (motorcycle rear) at that location the roller has on one side the black helix flat surface aligned with the axle direction. And on the other the 45 degrees alu helix part. Distance between the flat surface and the other helix contact area is about 1,5 times the roller diameter. So there is some play there.

The rear sheave is directly connected to the helix and to the rearwheel axle.

When i push the rollers into the helix i am pushing against the spring. So the more the rollers enter the helix the more tension there is on the spring and makes it want to change back to low gear.
Added sheave pressure on sec c.v.t. counteracts steady pressure in primairy at a steady r.p.m. causing it to shift to lower gear.

When i left out the helix parts and went for a test run. The sec c.v.t. sheave pressure was not enough to make it past 60kph. With a note that this was done when i was on the 2.54 ratio.

And this is where it get's fishy. So far the way i've seen the connections would make it work opposite.

If i'm standing still, and i add rpm to the primairy. The weights move out, belt is gripped and yanked. My rear wheel sheave is still standing still and the roller get's yanked to the 45 degree side. Pushing it not to tighten the spring in the sec c.v.t. but the opposite.

To get beyond this point and rectify/check my assumption. I guess i'll have to make a base test. That'll be next week then.

I did a fuel up today and it is 3.57 liter per 100km. Which is an improvement compared to my normal 5 to 4 per 100km previously. But let's wait till i get more km's into it. (80mpg almost!)

Oh and i did make a movie of the broken helix. I remember it's here: http://youtu.be/Kd01mBvaPrU

[BertTrack]

Ok i have actually figured it out.

I had to make some force drawings but i got it.

http://youtu.be/cOHRcRsp4eY

Boils down to: The spring in the Invance LV remains as is. Doesn't get twisted, and isn't extra compressed through the helix.

The helix translates the rotation of the sheaves directly into the movement of the sheaves to and from each other. This means that as you pull on the belt the helix will translate the extra pulling force into a force that will add to the spring. Which will cause more belt pressure and/or a shift down.

When you lot go of the throttle the opposite happens. It will gear up. And since the pulling force isn't keeping the roller on the one side of the helix it can (at low speeds) get drawn far away from the load(alu) helix, this happens especially when you're braking on the engine. But since that engine brake helix has a gap the roller will end up at a distance from the load helix. When you then open up the throttle that roller has to go back to the load helix and if that happens to quickly it will slam into the load helix.

[BertTrack]

Had the secondary out.

Here's the movie explaining the thing a little more.

Seeing movement.

http://youtu.be/BfjPn_LPkzA