'12 Apex...clunk in drivetrain?

[Dootoblue]

New Apex owner (as you probably know).

When starting off, I have a clunk when plurping the throttle. I have never heard this on my Doos.

Almost seems like the chain case is slamming every time I plurp the throttle.

Normal? Do you know the noise I am trying to describe?

Thanks,

 

[erosled]

Loose drive chain? Loose track? Normal noise associated with the extro drivers initial contact with the track clips? Really hard to say for sure, mostly because I don't know what "plurping" is.

 

[Dootoblue]

Not sure this will help, but I should have typed "blurping"......quick 1/8-1/4 throttle blips.

 

[uncltomm61]

mine does this to but i think its the chain case but i dont know if you can tighten it because of the reverse gears but im going to try that first and see what happens

 

[erosled]

Ah, blipping! So you mean you are blipping the throttle enough to engage the clutch, but chopping it before the sled moves? That would create a noise, moreso if you have a loose track or drive chain. Could also be the primary clutch opening back up if you are spinning it over engagement speed, it'll clunk when it opens.

 

[Malibu]

Mine is like that to.found out its jusst normal noises.my first miles i thougt it was breaking down,but now it has gone 2200 km

 

[Dootoblue]

Yea, BLIPPING.....thats it...lol, my fault.

The sled has 30 miles on it or so, no loose track, etc.

If it goes away, I'll be very happy.

 

[TBay Sledhead]

Also known as burping the throttle.

 

[sleddog66]

dootoblue, you will soon learn that you really can not "blip" the throttle on these 4 strokes all the time, as with the engine breaking, it will make for an erratic ride. I used to "blip" my 2 smokes also, but that habbit has really disapeared now. LOL

 

[Dootoblue]

The "blipping" is when I'm getting going, not stopping. Like when I have to drive the sled in the trailer, I dont hold the throttle steady, I Blip it...lol.

 

[Ding]

Yep - roll on and roll off, no blipping - the throttle that is. The clunk could be from any one of a number of things already mentioned. It could even be from a flat spotted belt. One of the best ways to flat spot a belt on these 4-strokes is to blip the throttle incessantly. Even loading or unloading on a trailer, simply roll into the throttle and you will have much greater control.

I am convinced that blipping the throttle originally stemmed from people watching racers doing it. They are trying to get extra fuel into the engine to help cool it down when the engine is already running on the lean edge. Enough people copied this habit so now it is perceived as the way you should do it. Of course if you have a really loud pipe, blipping the throttle allows everybody else to hear it too. Personally I think it is silly to blip the throttle on a stock sled. But that is just one man's opinion.

 

[Dootoblue]

Ding,

Being my 1st 4 stroke (had a 12 Doo 1200x but rode it 3 miles, no snow last year here), I feel a "surge" that scares me when in tight spots (enclosed trailer/etc).

Just wanted to know if the loud "clunk" was normal......didnt excpect that from my 1st Yamaha.

In certain situations, I will continue to "blip".....maybe with time, my blipping will go away....like this CLUNK!

 

[thor452]

most likely from a loose chain mine was loose from new. easy to adjust

 

[Irv]

http://www.ty4stroke.com/viewtopic.php?t=115486

 

[steiner]

With Yamaha's mechanical reverse system you will always get a "clunk" from the chaincase when getting into the throttle on start off or a hard decel.