CVT TRIVIA ---lets play

[Hetrick Racing]

Ok as we all know some questions may have multiple answers,this is more for fun and some extra help to those that dont know or are new to the cvt world.
Also I want everyone to ask questions so I will start.

So question one

What is the common answer to this?

My quad takes off real good then about 10 foot out it falls off for a second then takes back off.
The torsion spring is new

[nastynotchback1]

Originally posted by Hetrick Racing
Ok as we all know some questions may have multiple answers,this is more for fun and some extra help to those that dont know or are new to the cvt world.
Also I want everyone to ask questions so I will start.

So question one

What is the common answer to this?

My quad takes off real good then about 10 foot out it falls off for a second then takes back off.
The torsion spring is new

The first thing i would do is mark the variator and recheck it.Then i would probably end up changing rollers.Possibly changing to a different tension torque spring.

[qcitytile]

rollers are to heavy

[Hetrick Racing]

That is what I was looking for
Sometimes though the new spring is not quite the same as the original,but "A typical" would be roller weight.

Your turn you ask one

[nastynotchback1]

Got a bike that takes off hard and then continues to rev but feels like the brakes are on.

[jake55]

After servicing the CVT, if you do not replace the belt, does the old belt need to be reinstalled in the same direction? if so, why?

[nastynotchback1]

Originally posted by jake55
After servicing the CVT, if you do not replace the belt, does the old belt need to be reinstalled in the same direction? if so, why?

i would say yes because of the wear pattern but i have never had any ill affects from not replacing it the same way.

[Hetrick Racing]

Originally posted by jake55 After servicing the CVT, if you do not replace the belt, does the old belt need to be reinstalled in the same direction? if so, why?



i would say yes because of the wear pattern but i have never had any ill affects from not replacing it the same way.

I agree
Just like a drive belt on a car you should probably install it the same way just for longevity.But I dont see a performance issue.

[mcwilly]

I've always put my belts on so that the words/numbers are facing me where I can read them.....I never even thought about different belt wear.....I'm just OCD :D

[Hetrick Racing]

C-mon someone answer the question,,,lol

its eatin at me

[THARNESS]

Belt is too short or rollers too light or torsion spring too stiff

[chunky0071]

Originally posted by nastynotchback1
Got a bike that takes off hard and then continues to rev but feels like the brakes are on.


Let go of the brakes! LOL Roller Weights are to light!

[chunky0071]

Cvt gets really hot and cooks belts. every travels correctly spring is right rollers are good but still gets hot really hot?

[nastynotchback1]

Originally posted by chunky0071
Let go of the brakes! LOL Roller Weights are to light!

yeah but i have also had trans gears slipping causing this same issue.

[DAVYS DAD]

clutch engagement to high??lots of slipping makes lots of heat.

[dericsdad]

I have seen rear cvt pulleys crack and even split, but before they completely come apart they cook belts.

Otherwise, it's just the belt slipping too much. Maybe your rollers are too light, or the rider is constantly blipping the throttle...

[tyler70t]

Originally posted by Hetrick Racing
Ok as we all know some questions may have multiple answers,this is more for fun and some extra help to those that dont know or are new to the cvt world.
Also I want everyone to ask questions so I will start.

So question one

What is the common answer to this?

My quad takes off real good then about 10 foot out it falls off for a second then takes back off.
The torsion spring is new


Could be a fuel concern, not CVT.

[selbygirl]

like tylers dad sed . we had a bike do somthing similer but at around 50 feet. it seemed to be to much fuel line travel, did away with the cockpit and ran shorter fuel line . and cvts over heating and burning belts maybe the pullyes arent lined up strait

[Hetrick Racing]

Good question;where to start

In a situation like this find a starting point to eliminate questions in your mind.
1st I would check belt alignment

2nd check the engagement to ramp travel see if you are not using "1st" gear(easy way to do this put a line on clutch as you were checking travel then just bring the rpms up till the clutch hits a few times )check the height of ramp travel on engagement. like was said stall speed could be to high,if the bell is blue as well indicates worn shoe pak or to high on stall speed.
Possibly just to wide of a belt could be found with this as well.

3rd if above are good check your jetting. possibly the engine is not making enough power when the clutch applies making the clutch do all the work,this will overheat a clutch quickly.

[selbygirl]

a easy way i have found to see if belt is out of aliment , i take a dry arase marker and mark both iner sides of the variator and run the bike just for a minute or 2 ,then take the varitor apart and see what side wears the most

[EthansDad]

oh oh! I want to play! :-)

for the belt issues (breaking I think was the question?) heat is the problem. It sounds like yoda when I say this, but excessive force (like friction/overworking) leads to heat that ends in suffering! (broken stuff). "stuff" could be broke belt, melted rollers, or springs that won't hold up for 4 laps.

a couple of common CVT things that will lead you down this "dark side" of suffering (broken stuff!).

*belt alignment as hetrick said - big heat builder. sometimes crank is bent, or you shimmed it you wrong. either way, you have a oven ready to bake what you put in there.

*slippage - can come from a number of things, but over shimming the var half's is a big one. belt width and var shimming is a marriage. can't change one with out the other. you get it wrong, belt slips, causes heat...to thin a belt, or too long a belt can also give slippage.

*over worked clutch - I'm guilty of this - bringing the stall up higher and higher is fun. I had one of our bikes that stalled (started to take off) at over 10k! it was a beast to ride, but man, did it take off. the long play on that setup? I created an oven. the excessive force of the clutch shoes spinning up to 10k then hitting the clutch bell made wicked heat.

*over worked CVT - the not using 1st gear thing hetrick mentioned is the usual suspect there. if you "take off" in 2nd (just think I take off past the lowest possible ratio my cvt can make), then your CVT and motor have to work harder. excessive force, leads to heat...blah blah. can do the same mess up by having "over ratio". say your CVT is shifting out fine, but you get an idea to run a 26 tooth rear. well, you've made more work for your CVT, created more heat....dark side.

*wrong spring - bigger is better, right? not with springs. If I had a choice to setup a bike to use a heavy roller/stiff spring combo VS a light roller/soft spring combo I'd choice the light/soft setup. (think 5g/2k spring VS 4g/1500 spring). the stiffer the spring the more work your motor has to do to compress it (which means that HP is lost inside your CVT cover its not getting to the rear wheels and the "work" that HP does inside your CVT cover is make heat).



-EA

[nastynotchback1]

Originally posted by EthansDad
oh oh! I want to play! :-)

for the belt issues (breaking I think was the question?) heat is the problem. It sounds like yoda when I say this, but excessive force (like friction/overworking) leads to heat that ends in suffering! (broken stuff). "stuff" could be broke belt, melted rollers, or springs that won't hold up for 4 laps.

a couple of common CVT things that will lead you down this "dark side" of suffering (broken stuff!).

*belt alignment as hetrick said - big heat builder. sometimes crank is bent, or you shimmed it you wrong. either way, you have a oven ready to bake what you put in there.

*slippage - can come from a number of things, but over shimming the var half's is a big one. belt width and var shimming is a marriage. can't change one with out the other. you get it wrong, belt slips, causes heat...to thin a belt, or too long a belt can also give slippage.

*over worked clutch - I'm guilty of this - bringing the stall up higher and higher is fun. I had one of our bikes that stalled (started to take off) at over 10k! it was a beast to ride, but man, did it take off. the long play on that setup? I created an oven. the excessive force of the clutch shoes spinning up to 10k then hitting the clutch bell made wicked heat.

*over worked CVT - the not using 1st gear thing hetrick mentioned is the usual suspect there. if you "take off" in 2nd (just think I take off past the lowest possible ratio my cvt can make), then your CVT and motor have to work harder. excessive force, leads to heat...blah blah. can do the same mess up by having "over ratio". say your CVT is shifting out fine, but you get an idea to run a 26 tooth rear. well, you've made more work for your CVT, created more heat....dark side.

*wrong spring - bigger is better, right? not with springs. If I had a choice to setup a bike to use a heavy roller/stiff spring combo VS a light roller/soft spring combo I'd choice the light/soft setup. (think 5g/2k spring VS 4g/1500 spring). the stiffer the spring the more work your motor has to do to compress it (which means that HP is lost inside your CVT cover its not getting to the rear wheels and the "work" that HP does inside your CVT cover is make heat).



-EA

you can't play anymore:D

[Hetrick Racing]

lol--- Eric has been jousted from trivia

Ya know what thats the kind of stuff were looking for

[nastynotchback1]

Originally posted by Hetrick Racing
lol--- Eric has been jousted from trivia

Ya know what thats the kind of stuff were looking for


The problem is i am not smart enough to read what he writes so he's got to go lol

[EthansDad]

you can't play anymore

your too funny Nasty. I get the hint. if this was "CVT Surviver", I've just been voted off the island....

I'll just be over here in the peanut gallery if anyone needs me.....carry on with your trivia....

[selbygirl]

Originally posted by nastynotchback1
The problem is i am not smart enough to read what he writes so he's got to go lol same here ethans dad with all his charts and digrams , he shiould make a book .. cvts for dummies . i shore could of used a book like that a time or two at the track

[Hetrick Racing]

Ive got a good one.

Will any spring work with my cvt system ?

[Hetrick Racing]

Anyone playin

[selbygirl]

arent some springs wider then others. plus you got the big bikes with cvt . heck my bed has over a hundred springs in it but its not a cvt

[asadad00]

I guess you mean any spring strength 1000-2000, I would think any spring would work if the rollers were suited. Maybe not work as well as some other combos but it should work.

[hanker]

Originally posted by Hetrick Racing
Ive got a good one.

Will any spring work with my cvt system ?




I would think they would.

[don bassani]

Any spring ? That's a tough one.In theory any spring should work,how ever I could never get proper belt travel with really light spring even with super light rollers.I think the whole variator/rear pulley assembly needs the proper min/max spring and roller set up to work correctly so I will say NO.

[Hetrick Racing]

Actually the yes /no is the answer to be absolute,but for the most part a larger number of springs can get you through a day at the track,than not.
Lets just say you run a 70 with a 1250 and 3.5 rollers
If you would be at the track and your spring failed and all you could get was a 1500 or a 1000 just a small roller change could get you up and running.Now if a 2000 was all that was available it still could work for a day,just going to take a big change of weight.
Of course the weight would go up with a larger number spring and down with a smaller.
Some of the springs from the scooter world are very soft,so finding the proper weight is next to impossible.That is what Don is stating I believe.

I can say I get this call 3 to 4 times a week,usually on the weekend on my cell and we get them riding with what is available.

[don bassani]

I tried some super soft scooter springs with ultra light weights in an effort to reduce belt temp.I could not get that to work but I definately could make 1000-2000 springs work.

[Hetrick Racing]

What causes the performance on a normally good performing quad, to become inconsistent ? (MULTIPLE ANSWERS)

[hanker]

A bad spring,bad gas,and a worn out variator. Plus worn roller weight's.

[selbygirl]

electrical. bad ground/ bad kill switch . weak shoe spring. air leak, water pump

[nitrofish]

Dirty CVT. Atmospheric changes.

[dadofethan47]

temp and humidity. Oh and if you act like your married to it. The quad will act up anytime it sees fit. LOL

[Hetrick Racing]

Sorry I forgot we started playing this,must be getting old.
Anyway what I was looking for you guys hit on the head.
The bushing in the variator or the ramps worn do all kinds of goofy stuff,
and Jetting or carb problems.
Last year I took 3 new carbs out of the box and they wouldn't run correctly.

But the biggest carb problem is wear on the slide will make the engine very inconsistent.
Keep a close eye on the carb slide,, the slide is the first to get hit with dirt

[Hetrick Racing]

Someone else ask one

[fish-d-fish]

Its September in the great lakes area and my quad runs great in the am and horrible in the afternoon...why?...

[dadofethan47]

Originally posted by fish-d-fish
Its September in the great lakes area and my quad runs great in the am and horrible in the afternoon...why?...

I ran into this also racing sleds at spirt mtn in Duluth. Sled would rip in the am and be a headache in afternoon. This is the only place it would do it. And countless times on 4 diff sleds. We figured out it has to do with Temp. And the Humidity rising off the lake. Evaporation or what not. We used a air density gauge. Every afternoon we would have to jet down, every am we would jet back up. Like I said this is the only place when I was racing that we would have to rejet 2 times a day.