I have a lot of pops, poofs and farts on decell and between gear changes. Nothing real loud but aggravating.

I am running a 52.5 pilot, a 150 main and the needle is raised .030. The fuel screw is turned out 2-3/4 turns from closed.

I have a Harley dyna muffler and thats when it got bad. There are no leaks. I had none of this with the stock muffler. Well none that I could hear.

I can get it to stop by using a 55 pilot with the fuel screw turned out 3 turns. Not good as that makes the idle circuit too rich all the time but the pops are all but gone. It runs good with the 52.5 or the 55. Both have good performance. I had rather stay with the 52.5.

I read about cutting the spring on the TEV but don't see this as a solution. There only needs to be extra fuel on decell at high engine vacuum. With a weak spring fuel will come in sooner and be too rich when you don't need it.

There needs to be a way to slightly increase the fuel flow through the TEV only during decel at high engine vacuum . Thats when the idle circuit goes really lean and needs a shot of fuel.

What say you learned people as well as shade trees. Is there a way to increase the fuel delivered through the TEV and keep the stock spring so you only get it on decell at the highest engine vacuum.

Or do you have other solutions I havn't heard about.

you can eliminate the shift change noise by throttle & foot control, dont slap it shut & get on with swappin cogs,, piddle fart around & its liable to growl some.

on decel, if mine didnt rumble & growl, id rejet till it did..runnin down thru th gears, lissnin to it rumble? dude!

oldNslow wrote on 07/10/13 at 17:59:19:



7 answering annoying questions

I guess what I was looking for was how the TEV works, how it supplies the extra fuel on decel and how to modify it.

I know how to ride to keep the pops to a minimum. But even doing that there are still too many.

apache snow-FSO wrote on 07/10/13 at 18:51:03:


My experience with the O2 sensor and stock carb shows that the TEV is not effective in reducing the lean condition that results when the throttle is closed while the engine rpm's are above idle.....as occurs when shifting gears or coasting/decelerating.

I don't know if the TEV is overly restricted in an effort to reduce emmissions, and if allowing it to work sooner will be beneficial.  To date a few have tried modifying the spings......but I am not aware of anyone trying to change the jetting of the TEV to allow more fuel flow.

One fellow claimed to have success by using a spring from an automotive carb accelerator pump to replace the stock TEV spring.

You might be blazing a new trail if you want to explore fuel flow rather than how soon the TEV kicks in.  I don't know if the problem is the TEV not coming on soon enough.....or not providing enough fuel.  

Here are links to what has been done so far:

http://suzukisavage.com/cgi-bin/YaBB.pl?num=1342323516

http://suzukisavage.com/cgi-bin/YaBB.pl?num=1268545171

http://suzukisavage.com/cgi-bin/YaBB.pl?num=1318209614/0#0

What If the Hokey Pokey Really Is What It's All About?


ive wondered that very thing for years

When the bike goes lean you get imcomplete combustion so some of the fuel gets in the exhaust. If the mixture was richer you would get a more complete burn and less fuel in the exhaust. Thats my understanding anyway.

I know you said there were no exhaust leaks but have you checked the exhaust header bolts? They have a tendency to loosen over time. Did you loosen or remove them when you installed the Dyna? Replace the header gasket?


Just a thought