[rainking1978]

I remember reading something on ex500riders.com how to fix this so that you don’t get that popping/backfire noises when you close the throttle/decelerate after Sarachu install. Will rejetting solve the problem? Thanks.

 

[knightslugger]

no, it wont. What's happening is unburned fuel is exploding in the exhaust system. there's only one way to fix that. Fog can explain i'm sure.

and no removing the SMOG system does not help.

 

[fog]

First of all it's not a "Problem" but perfectlly normal. You just didn't hear it with the stock pipes.
The cause it fresh air being emitted into the exhaust by the emision control devices. just remove all that stuff and connect one of the hoses to the other nipple on top of the head and plug the airbox hole and the vacuum tap in the right carb and tha noise will go away. Do not re- jet open and adjust your pilot screws.

FOG

 

[knightslugger]

First of all it's not a "Problem" but perfectlly normal. You just didn't hear it with the stock pipes.
The cause it fresh air being emitted into the exhaust by the emision control devices. just remove all that stuff and connect one of the hoses to the other nipple on top of the head and plug the airbox hole and the vacuum tap in the right carb and tha noise will go away. Do not re- jet open and adjust your pilot screws.

FOG

When i did it, it didn't help at all.

 

[Guest]

ive seen the smog caps they sell and people have one-offed. are these necessary to remove the smog stuff?

 

[knightslugger]

kinda. you could fabricate your own if you've got the metal, a pencil, and a dremel...

 

[fog]

ive seen the smog caps they sell and people have one-offed. are these necessary to remove the smog stuff?


I told you what to do
. No
they are not necessary. just another decroative thing sombody figured out to sell. Connect the two air inletes to each other. All they are is a hole down through the head into the exhaust ports with spring one way valves to prevent most of the exhaust from blowing back into the fresh air valve.

On all the race engines I built I would tap and plug the holes in the head.

To Knight slugger you must have done somthing wrong or you have a false air leak in your intake system. Perhaps you left a vacum tap open.

FOG

 

[knightslugger]

ive seen the smog caps they sell and people have one-offed. are these necessary to remove the smog stuff?

I told you what to do.
No they are not necessary. just another decroative thing sombody figured out to sell. Connect the two air inletes to each other. All they are is a hole down through the head into the exhaust ports with spring one way valves to prevent most of the exhaust from blowing back into the fresh air valve.

On all the race engines I built I would tap and plug the holes in the head.

To Knight slugger you must have done somthing wrong or you have a false air leak in your intake system. Perhaps you left a vacum tap open.

FOG

No, everything was buttoned/pluged up nice and tight. I put Hi-Temp RTV sealant on the BRG Racing Caps to make sure they were sealed up. I did take the rubber (or whatever) wrapped reed valve out as i figured it was totally unnecessary (if not detrimental) if i had the RTV there.

 

[fog]

Well the popping is caused by fresh air getting into the exhaust pipe and re burning the residual gasses there. You have a LEAK somewhere, maybe it's your exhaust pipes them selves.

FOG

 

[knightslugger]

Well the popping is caused by fresh air getting into the exhaust pipe and re burning the residual gasses there. You have a   LEAK   somewhere,   maybe it's your exhaust pipes them selves.

FOG

That's possible i suppose.  I did have to get the right side pipe patched before the switch requiring me to remove the whole right side... but i was convinced that they were on there good and tight though.  However i don't recall installing the copper crush gasket, or that there was exhaust gases coming out of the headers.  Maybe it was the connection to the equalizer that did it...  Who knows?  I wish i still had the damn thing...

 

[Administrator]

I remember reading something on ex500riders.com how to fix this so that you don’t get that popping/backfire noises when you close the throttle/decelerate after Sarachu install. Will rejetting solve the problem? Thanks.

Edgar from Sarachu was invited last week... said he might join up, not sure if he did. I'm sure his busy, you know, making Sarachu's.

Maybe somebody can email him and remind him to join up if he hasn't already?

 

[rainking1978]

I really want to do this mod but not sure how. Is there a picture of what needs to be plug?

Thanks.

 

[maverick9611]

FOG:is not more efficient to allow the air in to burn the unburned fuel?

 

[fog]

FOG:is not more efficient to allow the air in to burn the unburned fuel?

Nah, unless you can measure the small additional amount of Jet thrust. Kinda like an afterburner. WOuldn't blow out a candle though.

FOG

 

[knightslugger]

I'd think that it would make it pass emmisions though...

 

[pikapp33]

another very easy method is cutting a small piece of sheetmetal for each cap (that the hoses connect to), to fit between it and the head (or in actuality the valve cover).

Remove the cap, set it on the sheetmetal.
Mark the bolt holes and around of cap.
Drill the bolt holes in the sheetmetal, and trim to match the cap base.
Rtv both sides of the metal and put the caps back on.

Same effect as FOG's method, just more work

 

[fog]

Actually there's nothing detrimental about the fresh air stuff at all. Removing it or leaving it on allie sama tinga.
As a racer I just removed it as just a thing that was in the way when doing the constant service work on the bike, and whatever it weighed. Same as all the light and inner panels. Heck I never even bothered with a gage cluster after I broke a couple of them.

FOG

 

[OreoGaborio]

Heck I never even bothered with a gage cluster after I broke a couple of them

HA!

One of my crashes this year sent me into the tire wall coming outta turn 10 and my gauge cluster ended up out in the middle of the track between 10 and 11 with bikes cruisin past on either side of it... cornerworker went out, picked it up, gave it back to me, i plugged it back in & it was good to go, tach & temp still worked Only broke the mounting tabs and the clear plastic cover. ;D

 

[heffay]

I remember reading something on ex500riders.com how to fix this so that you don’t get that popping/backfire noises when you close the throttle/decelerate after Sarachu install. Will rejetting solve the problem? Thanks.

Edgar from Sarachu was invited last week... said he might join up, not sure if he did. I'm sure his busy, you know, making Sarachu's.

Maybe somebody can email him and remind him to join up if he hasn't already?

I was lead to believe (by edgar) that he only imports surachus... he doesn't actually make them.

 

[fog]

Heck I never even bothered with a gage cluster after I broke a couple of them

HA!

One of my crashes this year sent me into the tire wall coming outta turn 10 and my gauge cluster ended up out in the middle of the track between 10 and 11 with bikes cruisin past on either side of it... cornerworker went out, picked it up, gave it back to me, i plugged it back in & it was good to go, tach & temp still worked Only broke the mounting tabs and the clear plastic cover. ;D

Ya should of left it there It's just a pound of useless weight.

FOG