help stealth my mini!

[raptorobbie]

Hi - new to the forum and just bought a new 08' 90cc DRR. Problem is, its a bit too loud for the neighbors. I got the "quiet pipe" from DRR which helped but want to know what the difference is between the DRR and the other 90cc 2-strokes from the mainstream mfg's like Polaris etc. I believe I saw a Polaris Predator that was quiet as could be zipping around the riding park we go to the other week. These 90cc cant all be this loud right? what's the difference?

Don't get me wrong - I know they're built for performance - which I'm fine with, its just hard to let him ride at our "home track". Thanks for your help!

[JIM GRACE]

well you hit it on the head with "they are built for performance"
it sounds like you would be happier with a trail rated quad
"taller seat height, narrow wheel base-flips easy,and poor suspension"
for noise reasons but i'm sure your rider would pick the drr..
screw the neighbor's and keep the drr:D

brandon's dad #55

[brainwashed]

Stealth bikes/quads are the way to go.

You should look into FMF 'Q Series' Mufflers that offer plenty of performance and are very quiet. Contact FMF for fitment to the DRR's. They might be willing to try to figure out something that will fit easily.

Another alternative is to look into getting a stock pull off silencer from a Polaris or similar and see if you can fabricate a way for it to mount onto your DRR.

Good luck and post here if you find something that mates up easily. Loud bikes and quads will only create more people that dislike our sport. Keep them quiet if you not on the track, and as quiet as possible even when racing.

[drr5]

quiet and 2stroke performance dont seem to go hand and hand, but maybe tracking down a stock predator exhaust may take care of your sound needs but my opinion is you will spend some time getting it to run good,

[raptorobbie]

Yes, I already purchased and installed the "quiet pipe" that DRR sells for this bike which cut the noise considerably and very little noticeable performance loss. Before that, I tried to fit a Pred 90 pipe on the bike but it was not an exact fit and did little for the sound.

Again my real question is - how loud is a stock 90cc Polaris or Eton or Kasea in comparison to the stock DRR? Please keep the replys coming! Thanks!

[brainwashed]

I actually just found this device through a thread on Thumper talk.

http://www.dirtwerkz.com/Pages/products/exhaust/dB_Dawg.html?gclid=CKSbz-69g5QCFR4sagodekxCWA

If you have a Polaris can, and it didn't help the noise much you might be as quiet as you can get the bike. The expansion chamber design is louder that a straight exhaust pipe and has more of a 'ping' noise to it.

[raptorobbie]

Thats interesting that you found that! I scoured the internet looking for stuff to make the exhaust note quieter and didn't see that product.

The DRR doesnt sound too bad now with the "quiet exhaust" on it - the problem lies in the fact that you have to pin it to get it going, and our small track in the back of the house is tight w/ lots of turns - so the bike is constantly hitting the top of the powerband - I'm hoping to tune the cvt so it engages at a lower rpm. Another work in progress.....

[forgiven]

Could you post a link to the "quiet" DRR pipe please. I looked and could not find it.

[raptorobbie]

forgiven ~ i do not have a link for the "quiet pipe" that DRR sells, all i can tell you is the part # for the 90cc, if i still have it at home. I contacted DRR directly for this both by phone and email - good people to deal with - they gave me the part # to give to my dealer and he ordered it for me. DRR has them in stock - dealer charged me $125 and had it in a day.

I wish DRR had all this up on the web-site to look at (i know its a lot of work) that would be sweet.


rob

[forgiven]

That's cool. I will call them today.

Thanks

[bulldogfallon]

I have the all black pipe is one piece (including silencer)..

Never tried it, but have one just in case

[forgiven]

If you could send me a pic Gary that would be swell.

[raptorobbie]

ok - this past weekend we put the DRR and the "quiet pipe" to the test. It failed :( There was a loss in power, enough that he could not climb hills he had no problem w/ a couple weeks ago w/ the stock pipe. Also, we fouled a plug to the point that it shut the quad down - plug looked like my bbq grill after cooking a couple slabs of ribs!!! mmmm ribs! Last but not least I'm not sure what is going on - or if its a combination of things - but I've not really been impressed w/ this quads take-off ability. Right now, w/ no one on the bike, I have to hit it full throttle, wait a second or two and then it decides to move - hopefully the front wheels are straight!! I just read an old post about stock Predators lifting the front wheels off the ground on take-off. Dont get me wrong the bike is awesome - suspension - brakes - etc but there's got to be something wrong!

I'm confused about what to do - try to deal with the quiet pipe and tune the quad to it, or scrap the quiet pipe and just never let him ride near the house!! Help - where do I start!!!

Thanks!:)

[brainwashed]

It sounds like you need to lean out the jetting with the quiet pipe.

Just as with as with a free flowing (loud) exhaust where you will need to richen the jetting - going to a more corked up quieter exhaust will require that you lean it out a little. I went through this with my KTM SX that I was stealthing out for trail riding instead of the track.

[jread14]

Yeah... They typically come from the factory rich and then you put the quite pipe on it and now it is even richer. What kind of carb does it have? Mikuni 16mm should be around a 100-110 and an OKO 21mm should be around a 110 main.

[raptorobbie]

I'm almost positive its the OKO carb. If stock is 110 - what would I go down to, and who should I get jets from (are all jets the same??) would any dealer have them? Also, should I be changing the pilot jet too?

I just started looking at the cvt last night - I did the sharpie test and the belt left 1/2" of sharpie line on the front bell - is that normal?

Also, I noticed on the rear clutch drum that the shoes hit, the drum was blue (from heat) in one area - is that normal?


thanks for all the help!

[bulldogfallon]

Quiet pipe with oko 85 to 90 mj and 35 to 38 pilot

Clutching will need some tweaking too.....this pipe makes power in a much lower range than mx pipe and cylinder

[raptorobbie]

bulldog ~ i want to order all the stuff for this quad from you - but didnt know if the Mikuni jets you sell will work w/ my stock carb (oko). Also, can i put the 1000rmp torque spring in a 90cc or are they strictly for the 50-70cc machines - keep in mind i want to play around w/ the cvt a bit and see what gets me the best setup w/ this quiet pipe.

thanks!


rob

[bulldogfallon]

The torque spring ratings is really dependent on the brand...

A ZTR 1000 could work in a 90, but a Malossi 1000 may not be the best choice....

It is also directly related to the roller weight in the front as well.

The OKO carb use the Keihin style jets, so the Mikuni jets won't work for your application.

[raptorobbie]

ok Gary - I pulled the carb yesterday and its a 24mm PWK - it has a 130mj and a 40pj - should i still go down to the 85-90mj you recommended - let me know what you think.

thanks!