Is my shaft too long???!!!

[metalthrashinman]

Knew that would get a reading! But seriously, I have a Tav2 30-100 Torq-A-Verter installed on my EX27 Subaru Robin engine. Didn't really fit the motor without major modifications; but nonetheless, it is on. Functioning very well, but for the fact that when the belt gets a little worn, it will not shift into high gear. I had to space the mounting plate out and cut down the spacer washer to line up the pulleys. Now that I did that though, the mounting bolt is bottoming out on the shaft which leads me to believe that the travel distance that the drive pulley needs to move has been increased by the fact that the spacer washer has been decreased.

Question is-- do I cut down the engine drive shaft to move the drum driver closer to the sheave stationary?

Question 2 is that I saw somewhere that there is an adjustment on the springs for the blue garter spring assembly that would make it travel easier. Three settings as I remember. One for acceleration, one that is factory set for midrange, and one that makes it shift faster. Is my fix simply to change that factory setting?

Any and all advice is welcomed and much appreciated!!!

 

[metalthrashinman]

OK... Took it apart. The engine shaft does not protrude futher than the hub driver thereby leading me to believe that the shaft is not too long. Even if I did cut it down, the hub driver would still be the mounting point of the drum driver.

Any hints on why it will not shift to high gear??

 

[r97]

maybe your ratio is too high, russ or someone prob has the exact answer

 

[redsox985]

That's what he said!

The 3 stages you're thinking of are the spring tension on the driven spring. If you look at the outer cam, it should have 3 holes labeled "1 2 3." I believe that 1 is for more offroading, 2 is a moderate, and 3 is more for road. I may be wrong, but I have some level of confidence lol.

 

[metalthrashinman]

Thanks.

My problem is that this is a brand new (and not cheap) unit that shouldn't be having any issues at all, agreed?

What do you mean by "ratio is too high"? I have not changed anything on the unit, and it was shifting perfectly for about 6 hours...

Could it just be maintenance? I am running it without a cover because it is not available yet, and it hasn't rained here in a long time making it very dusty...


What if I shortened the length of the hub driver a little?
Thanks again.

 

[r97]

you may have gotten dust in your tc,if the tc wasn't set properly for your cart or if the pulleys are not the correct distance apart for the belt your using it could cause fast belt wear, how worn down is the belt?

 

[metalthrashinman]

you may have gotten dust in your tc,if the tc wasn't set properly for your cart or if the pulleys are not the correct distance apart for the belt your using it could cause fast belt wear, how worn down is the belt?

It may be dust. I'm not sure. I reassembled it after blowing it out and now it is shifting well again. Could it be that when the belt gets really hot it will not travel to the top of the drive pulley?

The pulleys HAVE to be the correct distance apart because they are both mounted to the supplied mounting plate and the drive pulley is in the exact center of the engine drive shaft.

I am using the supplied belt, so I know it is correct. It is hard to tell how worn it is. It actually does not look bad. I do notice some 'bubbling' on the angled side of the belt though which leads me to believe that the belt is getting too hot. There was one time that it was too hot to even touch...

Blazkowiez, where are you on this one? Tried to PM you but your box is full. I know you said in your post that, "The only part that would need lubrication would be the inner side of the outer cover on the main assembly where the aluminum piece rides on it using centrifugal force", but what about using dry lube on the splined hub driver that the sheave(movable half) travels on?

Oh yeah, if this helps, I am using an 11 tooth front sprocket and a 48 tooth rear sprocket.

 

[redsox985]

That 11:48 ratio may be causing the over heating. Your belt is trying so hard to pull your arse around. If you lower the ratio to like a 11:60 ratio then your TC won't be trying so hard. With the new ratio, it would put less strain on the unit.

 

[metalthrashinman]

Here you can see where I had to fill in the factory holes and make my own. I bought bolts that screwed in and used my grinder to eliminate everything but what was left inside because unfortunately, the holes that I needed to mount the unit would have been exactly in the middle of the two factory holes. I was sure that the thin walls remaining would tear through. I did all four but can only show one in a pic.

 

[metalthrashinman]

Here you can see why I had to do the bolt pattern remake. The opposite end of the driven pulley actually hit the motor when attempting to use the factory drilled holes. The plate would not fit either up or down with the factory holes. No way at all.

You can also see some of the custom steel that I had to make to space the motor higher. There is more custom steel underneath the plastic that you cannot see...

 

[metalthrashinman]

Some final pix to see. Took about 40 hours to overcome all of the problems.

 

[metalthrashinman]

That 11:48 ratio may be causing the over heating. Your belt is trying so hard to pull your arse around. If you lower the ratio to like a 11:60 ratio then your TC won't be trying so hard. With the new ratio, it would put less strain on the unit.

OOPS. "1004 TC2. 1" bore, 10 teeth. #40/41 chain. 8-13 hp engines."

Also if they advertise up to 13 hp, why would I be having any problem with my 9 hp?

Note -- it is still shifting well after dis and re assembly.

 

[newrider3]

Who is advertising a TAV2 as capable of 8-13hp? That chinese clone company? The original Comet TAV2 was usually rated at a max of 8hp, some people even had to step up to a 40 series with their 8hp when running heavy weight or big tires.

 

[redsox985]

Putting more teeth on the rear sprocket will help reduce the strain on the TC unit. A larger rear sprocket would be worth a shot. And 10:48 is also 1:4.8. Trying a 10:60 or 1:6, possibly 1:7, would lighten the load on the TC and belt.

 

[metalthrashinman]

Who is advertising a TAV2 as capable of 8-13hp? That chinese clone company? The original Comet TAV2 was usually rated at a max of 8hp, some people even had to step up to a 40 series with their 8hp when running heavy weight or big tires.

http://gokartsusa.com/tav301bore4041chain.aspx

Judging by the pictures, would you consider my tires heavyweight or big?

 

[metalthrashinman]

Putting more teeth on the rear sprocket will help reduce the strain on the TC unit. A larger rear sprocket would be worth a shot. And 10:48 is also 1:4.8. Trying a 10:60 or 1:6, possibly 1:7, would lighten the load on the TC and belt.

That I understand, but I do not want to lose any top end speed. I did, in fact, go down 12 teeth on the rear sprocket for that very reason expecting that a 13 hp TC could handle the extra load.

So are we all thinking that the TC is overloaded and overheating? Remember that it is primarily driven by my 109 lb son...

I must add though that this kart will yank me (200 lbs) right up a pretty steep hill I've got in my back yard without any hesitation even with my son aboard too. It's just that it has had problems shifting into high gear intermittantly...

 

[redsox985]

These are just possibilities as to what may be causing your belt to boil and bubble. I'd suggest a few more teeth on the sprocket, but this will sacrifice some top speed.

 

[metalthrashinman]

Just drove for 1/2 hour with no shifting problems. I ordered 3 new belts and am awaiting their arrival. Honestly I would rather replace the belt every 10 hours than sacrifice any top speed. I can get them for $17.00.

Maybe it was just dust...? Blaz did suggest cleaning as part of normal maintenance, and I am getting VERY good at taking it apart. Hey, where is he anyway???

BTW, any opinions on my work? How does she look? At 55 - 60 mph, she is pretty darn fast. Gets up there in a hurry, too!