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General => General Discussion => Topic started by: macocoy on March 14, 2011, 11:52:05 PM

Title: Exhaust washer restrictor
Post by: macocoy on March 14, 2011, 11:52:05 PM
Hello everyone,Can anyone tell me how to or where to find the washer restrictor in my exhaust,is it true that I also have to rejet,.Pictures would help a lot in locating the washer..Thanks much..
Title: Re: Exhaust washer restrictor
Post by: spr0k3t on March 15, 2011, 04:59:10 AM
The restrictive washer is also the header gasket.  You will need a replacement gasket without the restrictive washer attached.  To get to it, unbolt the exhaust on your scoot (knowing which scoot would also help to find pics for).
Title: Re: Exhaust washer restrictor
Post by: macocoy on March 15, 2011, 05:58:51 AM
Thanks for giving me an idea,my cdi and boss drive is derestricted exept for the exhaust since I had no clue where to find restrictor.My bike is Sting 50 known more as Yup50 2009....Aloha from Hawaii..
Title: Re: Exhaust washer restrictor
Post by: Whisper on March 15, 2011, 04:29:48 PM
Should be easy to find - the exhaust pipe is generally held on by 2 bolts.  Sometimes the washer is welded to the header, but it is easy to grind away the restricting portion.

You can reuse your exhaust gasket - Just cut away (razor knife or scissors) the unneeded part.  Heck, you could probably get away with the hi-temp make-a-gasket goop.  (I think it is sparly orange colored)
Title: Re: Exhaust washer restrictor
Post by: macocoy on March 15, 2011, 08:45:13 PM
Thanks Whisper,are u talking about the muffler(end or tail of exhaust system),pictures will help a lot,.Header means the beginning of the exhaust system,sorry English is my second language.
Title: Re: Exhaust washer restrictor
Post by: macocoy on March 15, 2011, 09:31:10 PM
And do I need to re-jet after removing restrictor in exhaust,or u can just leave the bike as it is?Thanks
Title: Re: Exhaust washer restrictor
Post by: spr0k3t on March 16, 2011, 01:56:39 AM
When derestricting the scooter, you shouldn't need to upjet.  However, any change to the intake, exhaust, or combustion of the engine, you should consider upjetting.
Title: Re: Exhaust washer restrictor
Post by: macocoy on March 16, 2011, 03:39:20 AM
Sprok3t ,thanks for that info now I can go ahead and try to remove whatever restrictor is there in exhaust ,I'm gonna try and take out the header tomorrow and look for restrictor.Does anyone have pictures of how this looks and picture of header just to make sure.Thanks.Mi bike is Sting50/yup50, it should be similar to people50.
Title: Re: Exhaust washer restrictor
Post by: Whisper on March 17, 2011, 01:49:34 PM
That should be dead simple, Mac - Just start at the muffler and follow the exhaust pipe to the engine.  The exhaust header should be held on by 2 bolts.  

The restrictor will look like a washer, but the center will not be a perfect circle.  If there is no washer, look at the exhaust itself, where it attached to the engine - It may be welded in as part of unit.

WHATEVER YOU DO - follow the torque specs for tightening the bolts on the header EXACTLY.  If you over tighten them, as the flange heats up and expands, it will easily pop the bolts/studs right off.
Title: Re: Exhaust washer restrictor
Post by: macocoy on March 18, 2011, 09:21:24 AM
Hey Whisper thanks for the warning about the torque spec,I better get me one from auto shop,and finally get the last restriction of my sting 50 eliminated.40mph is all I'm after for on level road,and will be satisfied to have a little bit more power going uphill.
Title: Re: Exhaust washer restrictor
Post by: Whisper on March 18, 2011, 12:45:39 PM
No problem - Unfortunately, I learned that tidbit through experience derestricting a Vento Phantom 150.  Luckily, it broke at the flange, leaving me enough room to remove the stud with pliers.  Easy fix, but I got lucky.  I knew when it happened too!  It was LOUD!

You can totally get 40mph out of a fiddy.  ESPECIALLY a 2 stroke.  Make sure your tires are up to the task.  Tell us how it turns out!!!
Title: Re: Exhaust washer restrictor
Post by: macocoy on March 22, 2011, 08:38:54 PM
Hey whisper ,just discovered that my exhaust may have catalytic converter,it has this 4-6 inches pipe that flattens and ends.Also has a rubber tube attached to the main exhaust.Not to sure what's best to do.Buy aftermarket exhaust?Or cut off the extra pipe?
Title: Re: Exhaust washer restrictor
Post by: Whisper on March 23, 2011, 01:23:24 PM
That is way odd.  I have no idea what either of those would do - Can you post a pic?

If they don't seem to be retricting the exhaust, I'd say leave 'em alone.  If you have a friend with a MIG or a buzzbox, you can chop and cover the hole.

If you really need the engine to breathe easily, aftermarket is the way to go - However, they tend to be LOUD.
Title: Re: Exhaust washer restrictor
Post by: macocoy on March 26, 2011, 09:01:24 AM
Hey whisper sorry been busy,I can't upload pic from my IPhone(my only Internet access)but I went to dealer to ask about the extra pipe on my exhaust and he said it's a noise dampener,not to sure he might have made mistake,but I guess I'll upgrade to aftermarket exhaust soon,I'll let you know what happens then.
Title: Re: Exhaust washer restrictor
Post by: Whisper on March 28, 2011, 04:53:59 PM
If you want to try it on the stock exhaust, you can probably get a local muffler shop to chop and weld the hole while you wait for 10-20 bones.  Or a case of beer.  ;D

I used this technique to great success before I got my MIG.
Title: Re: Exhaust washer restrictor
Post by: freemo on August 16, 2017, 07:57:43 PM
Hi Guys,

Have you got any instructions on how or what to do with the leftover air valve that connects to the stock exhaust as I am replacing with a LeoVince TT exhaust?

Cheers.