Cvt Newb

[pacman]

Hi Guys,
We're gearing up to start racing this spring with my sons DRX90. It's basically a stock machine as it is.

I want to learn how to tune the CVT. What is a good resource to learn about these clutches? I've watched a few YouTube videos and read as much stuff as I can find on here, but I really have not been able to find a wealth of information on how to tune the DRR CVT or what kind of routine maintenance I should expect to be doing between races. CVTs are so foreign to me and I need to get a handle on them. Can anyone point me in the right direction?

Thanks

[fomospede]

well your at the best chance for great info
just ask some ?? on here and someone will get you going
1st i would call one of the sight sponsors and tell them what u have and
let them start you in the right direction after that come here and ask ?S
many here tune at a national level you will not go wrong!!

[pacman]

I get that, but I don't want to be a total pain in butt with really dumb questions...

Here are a few questions I have, off the top of my head:

-We're new to quad racing. (I've raced motocross for most of my life) My son is definitely novice. He weighs about 135lbs. Do I need to modify the stock DRX CVT for racing?

-Durability: all I keep hearing is what a pain the CVT's are to maintain. I'm fine with that, but I don't even know what I'm supposed to maintain. I had one dad at the track tell me that I'd need to take the CVT apart every race and clean it. ok... what am I cleaning specifically?

-Belt: how do I know when the belt is shot?

I mean... maybe I'm getting ahead of myself here. We are going to start racing in about 6 weeks. We got the quad(used) at the end of Fall-2012 and we only got a few rides on it. It's a very lightly used machine so I THINK that the motor/cvt is pretty fresh. There will be a lot of practice before the first race. Right now I don't have a particular NEED or COMPLAINT about the quad, but I want to be pro-active in making sure it's setup correctly for my sons weight/riding ability.

How are most guys doing it with the CVT setup? Do you just go to someone like Hetrick or Koolkidz and ask them for a CVT kit, or do you buy a bunch of rollers/weights/belts/etc and experiment?

If it isn't obvious by now.. I BE CONFUSED! haha

Thoughts?

Thanks

[nastynotchback1]

Call me an i will talk cvt with you.Too much info to post.Thanks Trai

864-993-6956

Go on g-force's web site and check out there tech page. It will help you get the basics of the cvt set up.. Once you get the basics down tunning is pretty easy...

[ontargetracing]

CVT's are not that bad and actually pretty fun after you get it figured out IMO.
There are Many schools of thought on setup and maintenance. Most "national" racers will change torque springs every moto and rollers and belts almost as frequent. If you are just running a stock/stockish bike and still learning you can get away with allot longer intervals. We are really competitive on our stock bike and I can usually do an entire race weekend on one setup, don’t even pull the cover off unless I have to. It also depends on the springs you run, I like the red malossi springs for the stock bike but they don't last long, you can see the difference by the 2nd moto. Good thing is they are usually cheap because no one likes them ;) For rollers I just clean and reuse them until you can see them start to wear/flat spot. Belts.. I have yet to change one in our stock bike. Although, after every race weekend/practice I do pull the cvt completely apart and clean and inspect everything.

Heat is the major factor that kills the rear spring (again IMO), so you want to vent the cover as much as possible (with in reason), also put a vent in the starter hole etc...

After you find a good setup for your bike and whatever track/tracks you run, it's cake from there..

Just know this, what works for one rider/bike may not work for another.. at this stage it’s all about confidence and comfort (IMO).. your new rider may not like a screaming clutch setup that hits hard at high RPM's, even if that is the idea setup for your quad (I’m not saying it is).

I have a good setup that we run in our stock apex and I have used it in a stockish DRR with good results (got it from Bryan Kirkland) although my rider is much lighter so it may not work for you. You can PM me if you want it.

I would just post the question for a good basic setup for a stock bike and see what you get.. also, I would call one of the big four and ask them also, since you will be needing a few parts. I recommend Marc at Hotquads.. you cant go wrong with Justin @ MAX RPM either.

[desratt]

Where ya racin?

[pacman]

@nastynotchback1- During the week I'm working a lot of double shifts, but I'll give you a call when I get some time. Thanks.

@fast1-forlife- I just read it. That's what I was looking for. A very good starting point explaining the basics of the various components. Really helpful.

@ontargetracing- great info. How do you vent the cover? Drill holes? I'm in the north east and spring races are usually very muddy. How do you deal with that? Thanks.

@desrat- district 34 NY, NJ. Dist6 PA. We're going to start with motocross and I'm hoping to get him to race some of the hare scramble series with me too.

[jerkyboy]

How old is he? At 135lbs I would be a look to get him shifting and away from a cvt. Just a thought.

[pacman]

He's 10. He's big for his age. Very tall and overweight to boot. Getting his weight down is my #1 concern. My wife and I have been doing a much better job at this lately. For the last 2 inches that he's grown, he hasn't gained a pound.

He has had a TRX90 for years and he is capable of shifting(well... automatic clutch shifting). I just didn't want to spend thousands in upgrades to make the TRX competitive... It seemed to me like the CVT's were the only production machines that would be competitive in his age/skill level/class.

[ontargetracing]

pacman,

yes, you can drill some holes.

also...

1. Make sure you have a vented cover.

2. I take out that stupid foam filter thing.

3. I also don't use a cover for the hole in the back by the clutch.

4. I put an outerwears cover (www.outerwearsracing.com) on it to keep rocks, mud and dust out.

5. I also put an airbox vent in the starter hole

6. you can always tape up holes or put a plastic cover over them if the rain/mud is too bad.

I only use the outerwears cover and have never had an issue.

[pacman]

Having a real hard time finding that outerwear cover. The only place I can find it is on EBAY and there is only one available for $50. I've searched DRR dealer websites. Even the Outerwears website doesn't list anything for DRR's.. or at least i could not find anything.

Also, not sure what you mean by "Airbox vent in the starter hole"

I'd love to see a picture of what others have done to the cover for ventilation. How big are the holes you guys are drilling and what is the placement of these holes. I don't want to ruin the part. I'm on a tight budget.

[fomospede]

gforce has the outerwears
we run xc and use a polaris cover
we dont add holes and the openings are covered with outerwear material ,you can buy just the material. and the single outerwear cover over that
weve had no issues with heat build up

reducing heat in the cvt will lengthen intervals of maintenance needed to springs

also buy your springs in bulk as they change a little lot to lot ,this will keep you from possible retuning of cvt

[ontargetracing]

Air box vents - (http://www.rockymountainatvmc.com/p/43/53/174/1429/-/6786/Uni-Filter-Air-Box-Vents) just pop one in the starter hole.. keeps the crap out and lets some fresh air in.

Most vent holes are about 1/4" around the outside of the rear where the clutch is.

For the outerwears cover you can get them from hotquads, max rpm, g force and others.. and I think retail is around $50.

[pacman]

You guys are awesome. Seriously... thanks so much. I'll dig into all of this tomorrow night when I'm home. It's been 4 double shifts in a row. I need a night off to get this all going.

[pacman]

Do you guys use a tachometer to assist with tuning your CVT? If so, what kind?

[fomospede]

they are good reference for spring wear
but i do not tune with one

[ontargetracing]

A tach is good for seeing when the clutch engages but we don’t use one... just SOTP (Seat of the Pants) dyno here. A stop watch also comes in handy for checking acceleration.

[nastynotchback1]

DTI-20K is a great tach to put in your tool box and can be bought at most mini quad part suppliers.I would not try to tune a clutch with out it.I also have a stage 6 tach with recall that i have not installed yet.It will stay on the bike and let me see if we are over revving the motor.

[edwardsp&b]

Yes, you only need a tach once you get to fine tuning your CVT. I wouldnt run out and buy the most expensive tach out there, but when you get into setting the stall on your adjustable clutch, you need a tach. There is no other way to correctly set your stall. (when clutch engages) to where you want it. By adjusting our stall on our race bikes, we could make them launch better. After a million test runs, we figured out at what rpm our bike launched the best. This and getting your jetting spot on is what seperates the weekend/local racing dad, to a top National riders dad. Every kid that won a championship on CVT's had Dad's that knew how to fine tune and get every little bit out of there bike.

Unless these other guys have a magic ear, or can grab the coil wire and spit out rpm numbers, you have to have a tach to adjust stall. I imagine you could ride it and guess at where your stall is, but when Im spending alot of money to go race, I dont want to be doing any guessing.

If I were you, I would start buying from a reputable dealer, and speak to their tech guys on most of your questions. I had the same questions (where you feel like a dummy asking everything) when we first started racing. Thankfully Marc @Hotquads was there for every late night phonecall. Mike Deal with Gforce is really good too! Every question you could possibly have, they have ran into it or know the answer.
Bryan
Bryan

[fomospede]

no matter how you go about tuning do what works for you!
we tune ares to run a hour race not a 3 lap 5 minute race
i think the seat of the pants method for me!

[brian250racer]

Originally posted by edwardsp&b
..or can grab the coil wire and spit out rpm numbers
That's funny right there(and painful). Seriously, this thread is really helping me out as well. After 14 years of racing myself, I am finally letting my boy start this year, and I am trying to set his CVT up before his first race...

[ontargetracing]

pacman, this vid will help you with the basics of CVT service.

http://www.youtube.com/watch?v=eUkyyIonfIM

here is another page with some good info.

http://www.atvyoungguns.com/0-12-Hot-Quads-Race-Tech-tips.html

[pacman]

OK. So I think a tach will be in next months budget. Seat of the pants will be the method for now. I have to buy a trailer this month and it's cleaned out my funny-money fund. A drunk driver totaled my F250 at the end of last race season so I need new moto-transportation.

That youtube video is perfect for me. Going to dig in tonight.

Does anyone know the torque settings for the nut on the bell and the variator?

[pacman]

oh yeah, two more questions:

1. Did you guys leave the electric start on your quad?

2. I bought my son a set of Cycra roost guards for Christmas. I was looking at the handlebars last night when I got home and I can't see where I'm going to mount them... There is no space on the stock bars. This lead me into trying to see what others have done by looking at pics on the internet today. I couldn't find any really good pictures, but It looks to me like a lot of guys have removed the starter-switch/headlight switch/stock-kill-switch from the left side of the bars. The right side had me scratching my head a little too. It was 11:30 at night and I had just waorked another 13 hour shift so... maybe I missed the obvious. Any advice?

[fomospede]

We use powermadds has slim mounting perch

Racer is starter deleted

Practice is starter intact ,easier and just funner when play time

If you remove it
A freeze plug makes a great plug if not venting there

Also you will need to place a shim the thickness of starter clutch ,hardened steel nothing soft

[tyler70t]

I see you are from NJ, if you want that CVT tuned take it to Steve Wotring, Steven623 on the forum. He will definitely make the motor/clutch perform @ it's peak!!!! Are you going to race the MDRA series?

[ontargetracing]

yes take all that crap off... everything thats not necessary.. for torque settings just drive them on with an impact, don’t really need to worry about it unless you have a super powerful gun (I have stripped a nut with an air gun). I use my electric impact even at home that way I know I can still get them off at the track with the same gun.

handguards all depend.. on how they mount and the bars you run and if you cut them down at all etc..

[quadrider79]

U could also get ahold of Don Bassani. He is in northern New Jersey. I think around Sussex. He too is an awesome CVT tuner. Wotring is good too.

[pacman]

thanks again guys. Really useful stuff and much appreciated.

@tyler70t - Yeah we're from Northern NJ so a lot of the MDRA tracks are a little far for us. I think we'll be doing a mix of dist34 and NEATV races. Who knows though, we're not looking to run the entire series in any of the different clubs. We'll probably bounce around and do whatever race fits our schedule best each weekend.

ALSO, Another easy question... On the parts diagram it shows a spacer/washer between the head and the pipe. I assume that is some kind of restrictor and that is why I don't have it? Is there supposed to be any kind of gasket between the pipe and head?

[ontargetracing]

Yes there is a gasket between the pipe and he head

[asadad00]

Originally posted by ontargetracing
pacman, this vid will help you with the basics of CVT service.

http://www.youtube.com/watch?v=eUkyyIonfIM

here is another page with some good info.

http://www.atvyoungguns.com/0-12-Hot-Quads-Race-Tech-tips.html

That younguns site is great , thanks for posting that link, I never saw that before. That is the kind of detail I need, I may start building my engines.

[pacman]

so I've been playing around a bit with settings. I setup a starting area on my long driveway to test/time starts. We shaved 2.5 seconds off his starts just by changing the rollers from 4.8g rollers to 4.5g rollers. What a difference. It's pretty awesome seeing immediate results like that...