Loud knocking noise HELP!

[yfz27]

Son was riding today as soon as he landed a jump there was a loud knocking noise coming from down under. The quad will start up and idle fine but as soon as you try to go it makes the very loud and unpleasant noise. Where do I start looking? I'm still new to these quads and need a crash course in CVT mechanics. Thanks

It maybe your tranny gears

[Nichols Atvs]

Lift the back tires off the ground and spin the tires i think youll find the gears will hitch and that is a sign of broke gears Then pull off the cvt cover and check out the cluches take off the back clutch . drain the tranny fluid and remove the six allen wrench bolts to reveal the gears and take a peek. Replace if needed .Then start to teach the rider to let off the throttle in the air if that cant happen youll need a slipper clutch. good luck

[yfz27]

OK thanks there was a definate hitch with the rear wheels off the ground. I will tear into it tonight and see whats up. I was having him try to land with the throttle on so it was a smoother landing. My fault I guess.

[Rcarroll]

Welcome to the wonderful world of cvt's. Sounds like the tranny. Nichols Atvs has given you some good advice. Also check the case to make sure it did not crack.

[raidernut]

Without a slipper clutch, odds are this will continue to happen. Teaching them to let off the gas when jumping will help, but this is not the proper way to jump, so get the slipper.

[yfz27]

So I got it apart and yes there is metal everywhere. I pulled the cover to access the gears and then pulled out the first gear. How do I get out the second gear? Do I need to pull the front sprocket? Can't seem to get the nut off it even with an impact wrench. Any ideas. Thanks

[raidernut]

yes remove nut and sprocket

[yfz27]

I want to thank everyone for their quick responses. Saved me alot of time. Got everything apart and will order new tranny gears from Les tomarrow and check into the slipper.

You Are Very Welcome, Toby

[dirttrack86]

Whenever that happens to me, Marc and Gary always tell me to put in a good pair of earplugs. It seems to help, the Knocking really quiets down when I do it. LOL:p Just Kidding!

[Rcarroll]

Ask him about a case saver it goes on the outside of the tranny on the sprocket side. The only thing is you may need to turn the front sprokets shaft down but he may have one that has already been done. I'm sure he will do a good job telling you what you need he is a good guy.

[Nichols Atvs]

Been our pleasure to help. Les should be able to get you the slipper clutch Daves clutch is fantastic .

[yfz27]

It already had a tranny saver installed. So is it a slipper clutch or a slipper sprocket that helps with breaking tranny gears and what is the difference? Seems people interchange the two term alot.

[Rcarroll]

They make both. The slipper sprokets help on breaking but you have to tighten the nut on the sproket after every race or practice. The slipper clutch seems to help alot more. Just depends on how much money you want to spend.

[JIM GRACE]

Make sure you check under the trans case for crack's!!
first time brandon broke his gears it put to hairline cracks
under the case which i repaired with jb weld. second time it
broke the case.

brandons dad #55

[Nichols Atvs]

Spend the extra money and buy the CLUTCH. Dont nickel and dime your self until you say I should have bought the Better the first time. Maintance is one thing but unwanted maintance sucks !Just my opinon.


Jim Grace
Dont you just love J B weld I hope the person that invented it is sitting on a tropical island somewhere saying .How the H*ll did i come up with this formula. (OH WELL BARTENDER CAN I HAVE ANOTHER DRINK !!HONEY WHERE DO YOU WANT TO GO NEXT )

AH -----THE LIFE!!

[bulldogfallon]

Our team has the DC bearing mod installed and we use the DRR hardened std ratio gears along with the DRR slipper sprocket and have no issues at all.

We spin higher RPMs with MK scooter cylinders (more than the quad cylinders) and no more breakages to speak of.

I am sure the clutch mod is a good idea, but it is quite expensive and we aren't able to use the hit clutch with the mod.

Marc from Hot Quads runs the same set up and no issues to speak of.

[JIM GRACE]

jb weld is awesome, it is also currently holding an important
bolt in place, that otherwise would have sidelined us for the weekend:cool:

brandons dad #55