Taking of my Cobras and putting on OEM exhaust this afternoon. Update- went well

[Cliff]

After work today I am going to attmept to remove the cobras from my I/S and install OEM exhaust.  That is, if all goes well...  I don't think there is anything tricky about this project, hope I'm right about that. Cobras are a bit too loud, especially on the longer rides.

[NITRO]

You should probably replace the exhaust gaskets while you're switching them. You'll get a ticking or popping sound if they aren't sealed up well.

[Cliff]

You should probably replace the exhaust gaskets while you're switching them. You'll get a ticking or popping sound if they aren't sealed up well.

Have new gaskets on hand, Just hope the nuts come off with out issues,, I did spray the nuts with wd 40 last night hope that helps.  Putting this on hold,, dealer has no studs on hand and I want to have a few on hand on the off chance that some break.

[Jay]

Were the carbs re-jetted when the Cobra's were installed?  If so, won't you have to put the stock jets back in?

[2qmedic]

Guess I need to find some way to have a link for this mod.

Ok, i have a possible solution for you.
 
I have done this on my bike. I have the Cobras 6x with baffles.
 
1-Take out the baffle.
2-Use 2 stainless steel scouring pads. (got mine from the dollar store) They are
wound up in a coil.
3-Stretch two pads over each baffle (for the Cobra baffles).
4-Use some .032 or .040 wire (or some type of wire) and wrap it around the pads.
This will help compress the pads as to not be so puffy when reinstalling back
into the pipe. (learned from school of hard knocks)
5-Reinstall baffle. (If I did again, I would use some type of oil or lube in the
pipe to help get them in again. It will burn off.)
6-Take it out for a ride.
 
If not quiet enough for ya, go another step.
 
7-Take the baffle to an automotive store and buy freeze plugs that will fit over
the end of the baffle exhaust port.
8-Drill a 3/4 hole (same size as the orignal piggy) and then attach it with a
bolt, weld it or however.
Note: With the 3/4 inch hole, I know that I have not exceeded the stock mfg back
pressure. I did try a 1/2 inch hole, loss in pwr. 5/8 may be doable, didn't
try that size.
 
The volume at 50mph is now the volume at 75ish. Needless to say that the orignal
sound level at 75 was just way too loud. If the sound at 50 mph (after you wrap the baffles) is acceptable, then I would consider this mod vs the expense of buying stock exhaust. It was
worth it for me.
 
Another thing would be to wrap the outside of the pads with some exhaust
material. It would probably knock down the bouncing sound waves around the
baffles even more. I believe the scouring pads would also help the material to
last longer. If I pull mine again, I will do this also.

Hope this helps,
Cheers 

[98valk]

Were the carbs re-jetted when the Cobra's were installed?  If so, won't you have to put the stock jets back in?

cobra's re-jet kit (and dynojet kits) only included needles and springs. no main jets. I guess for marketing it sounds better to say jet kit rather than needle kit.
 ONLY Factory-Pro.com jet kit includes main jets, plus needles and pilot jets.

[Tropic traveler]

Guess I need to find some way to have a link for this mod.

Ok, i have a possible solution for you.
 
I have done this on my bike. I have the Cobras 6x with baffles.
 
1-Take out the baffle.
2-Use 2 stainless steel scouring pads. (got mine from the dollar store) They are
wound up in a coil.
3-Stretch two pads over each baffle (for the Cobra baffles).
4-Use some .032 or .040 wire (or some type of wire) and wrap it around the pads.
This will help compress the pads as to not be so puffy when reinstalling back
into the pipe. (learned from school of hard knocks)
5-Reinstall baffle. (If I did again, I would use some type of oil or lube in the
pipe to help get them in again. It will burn off.)
6-Take it out for a ride.
 
If not quiet enough for ya, go another step.
 
7-Take the baffle to an automotive store and buy freeze plugs that will fit over
the end of the baffle exhaust port.
8-Drill a 3/4 hole (same size as the orignal piggy) and then attach it with a
bolt, weld it or however.
Note: With the 3/4 inch hole, I know that I have not exceeded the stock mfg back
pressure. I did try a 1/2 inch hole, loss in pwr. 5/8 may be doable, didn't
try that size.
 
The volume at 50mph is now the volume at 75ish. Needless to say that the orignal
sound level at 75 was just way too loud. If the sound at 50 mph (after you wrap the baffles) is acceptable, then I would consider this mod vs the expense of buying stock exhaust. It was
worth it for me.
 
Another thing would be to wrap the outside of the pads with some exhaust
material. It would probably knock down the bouncing sound waves around the
baffles even more. I believe the scouring pads would also help the material to
last longer. If I pull mine again, I will do this also.

Hope this helps,
Cheers 

Did the same steel wool wrap thing to Kim's Shadow 750 with Roadhouse 65's slip-ons. Knocked down the raspy-ness pretty good.


Charles, I was thinking about doing the same steel wool wrap to the Cobras on the '99 Valk I recently bought. How tight did you pack the steel wool on the Cobras? Did it knock out the raspy racket good enough? Kim likes the Cobra noise but I'm not so keen about it. I may keep the '99 for a while so I do want to tone it down a bit.

[Cliff]

The changeover went well (although not having a garage and working in the driveway i sweated a river or two)  Right side went clean with no issues, instlaaed new crush washers AOK.  Left side one stud broke, removed with vise grips and installed new one.  Sounds much better now.  The niose on the long highway rides won't drive us crazy now.  Now I need to get the cobras listed on the classifide section....

As to the question regarding the needles.... Don't know if they were changed out when the cobras were put on or not (installed by PO) but I check the condition of the spark plugs, they looked just fine.  I  photographed them for later comparison.

[2qmedic]

Hey Mr Tropic Travler,

Long time no talk to, how are ya'll doing?

To answer your question, I used 2 scouring pads per baffle. I got them from the Dollar store and they are wound up like a donut and I just had to stretch them over the baffle. I don't know if 3 pads would make a difference in the sound level(I think it would).

The thing here is that there is only so much room between the baffle and the pipe. That is why, after using a screw driver to help it go in, I thought that by wraping wire around the outside of the pads would help to compress it and keep it even on the baffle. Otherwise,,,,, the pads will not go stay in place on the baffle properly.

Then use some lubricant to help it all slide back in the pipe easier.

Don't know how quickly you are looking to do this, but hopefully, I'll be back on the bike with in a month (OJI) and could ride down for lunch and let you hear it.

Hope this helps.

[Tropic traveler]

Sounds like a deal Charles!
It will be a while before I'm going to have time to work on the '99. Next 2 weekends are taken up & I just started at the local Ford dealer, all my time off is over. The Lincoln dealer I worked at for 17 yrs sold out but I was able to get on at the Ford dealer that bought it. Mixed emotions on that! 
Plus my '97 still looks like this. :'(

Riding the '99 with the Cobras while the '97 is down has shown me that it is too loud!

[2qmedic]

Sorry to hear about the job , but!!!, glad to hear about the other job!!!

[PhredValk]

Keep your tools and gloves handy for the first day or so. I changed back to stock and my first ride, miles from home, the hanger bolts all went loose. Had to buy a wrench at Canadian Tire to tighten them, and burned my thumb in the process...
Fred.

[Chrisj CMA]

Keep your tools and gloves handy for the first day or so. I changed back to stock and my first ride, miles from home, the hanger bolts all went loose. Had to buy a wrench at Canadian Tire to tighten them, and burned my thumb in the process...
Fred.

Ya....until the crush gasket washer things get squished all the way down, the header nuts will be loose on a daily basis.  Tighten after every ride until they quit turning up loose 

[KW]

I laughed at the steel wool suggestion. It brought back some memories! When I was a stupid teenager I got a 'repair & show' ticket for my 69 Javelin being too LOUD! (Headers to Cherry Bomps, straight pipes out the back) I pulled into a parking lot down the road from the PD and STUFFED both pipes FULL with steel wool. The desk seregant came out, I started her up and he said 'good enough' and signed off the citation. I got barely around the corner and seriously 'tapped' down on her and BLEW the steel wool out all over the street . . . then lit up the tires. Stupid teenager  

[Titan]

Hey KW!

That's hilarious! Thanks for posting and reminding me of how stupid I was as a teenager!

When I think back about a lot of stuff I did, it really amazes me that I lived through it to see adulthood!

Well,on second thought, I guess I still do some stupid stuff!

[Tropic traveler]

What I have is some 00 steel wool on a roll, & plenty of it. I wrapped the baffles on the 750 but as we all know a 2 cylinder sounds nothing like a Valk.
What I'm looking for is a sound about halfway between baffled Cobras & the whisper quiet stockers. I don't want to go all the way back to stock like Cliff did but I am getting weary of the Cobra racket.
Being basically the lazy type, I guess I'm looking for a relatively easy way out!   
We loaned Kim's 750 to her brother last year so the memory of what it sounded like has faded from my brain.

[2qmedic]

Hey Tropic Travler,

I think you will like the sound of this. It still sounds good. You can still wake up the neighbors!!! with out waking up the whole town.

I'm no exhaust expert, just though about the purpose of the baffles and how they work.
The stainless steel wool just keeps the sound waves from bouncing around in the pipe (like an empty room) and being amplified prior to going out the exhaust

There fore, in theory, a little bit equals small reduction in sound level, alot equals higher sound reduction. If you are going to do this, use stainless steel. It woun't rust out.

So far, everytime someone e-mails me about this and then does the mod, they reply back with positive comments and "owe ya dinner". Just havn't made it around the country yet! LOL