[trotmaster]

Having just bought a '97 vn800 classic, I decided to take off the custom pipes that were on there and replace them with the old stock ones that were thrown in with the bike.

I'm now getting popping and backfiring everytime the revs drop. I understand from the previous owners that they never changed the bike's set up for the custom pipes, so the bike should be as it was originally.

Can anyone help as to what's causing this?

 

[cruznut6]

Replace the crush gaskets. If you re-used the old ones, it's allowing air to mix with the excess fuel that didn't burn in the engine, causing the "popping". Changing them is a cheap, easy fix! :wink:

 

[Classic]

I'd also recommend doing a search and getting familiar with Russian Wolf's web site which will answer all your questions as well as some you don't yet have.

 

[uechi kid]

Yep. Gaskets first. They are cheap and easy to do.

 

[okiecop]

If it has reed valves, plug the hose with a marble. My mean streak has the reed valves and it popped on deceleration after I added pipes. I did the marble trick and it stopped. Might check with other owners to see if you need to do this to yours.

 

[800red]

Having just bought a '97 vn800 classic, I decided to take off the custom pipes that were on there and replace them with the old stock ones that were thrown in with the bike.

I'm now getting popping and backfiring everytime the revs drop. I understand from the previous owners that they never changed the bike's set up for the custom pipes, so the bike should be as it was originally.

Can anyone help as to what's causing this?

If we can ever help.. let us now..

The “800 Club” Home Page
the "800 Club"

The "800 Club" e-mail
[email protected]

 

[RichLockyer]

+1 gaskets. They can't be reused.

 

[Rockett]

Do you know when the last time the valves were check to also, it may have been re-jetted for the other exhaust.

 

[trotmaster]

Conclusion

Thanks to everyone who helped.

It turns out that the gaskets just needed replacing. All sounds sweet now.

 

[Lee_2061]

Lucky you caught it before the De-Gas tablet jokes started.

 

[darkwalker]

Having just bought a '97 vn800 classic, I decided to take off the custom pipes that were on there and replace them with the old stock ones that were thrown in with the bike.

I'm now getting popping and backfiring everytime the revs drop. I understand from the previous owners that they never changed the bike's set up for the custom pipes, so the bike should be as it was originally.

Can anyone help as to what's causing this?

What kind of custom pipes were on there? I put some on my bike that are just too loud for my taste.

 

[trotmaster]

Vance and Hines StraightShots. A nice big booming noise, but not what I want for commuting through the suburbs at 7 in the morning. I just don't hate society enough!

 

[ZeroPunch]

Vance and Hines StraightShots. A nice big booming noise, but not what I want for commuting through the suburbs at 7 in the morning. I just don't hate society enough!

They should all be up by 7:00. I am. :wink:

 

[Deeppurple52]

Exhaust gaskets should do the trick. Also make very sure that you have not dislodged any vacuum lines. Your bike will run incredibly awful if you did.