After marble mod

[dober]

Over the winter I put on a set of bolt ons and did the marble mod.Starts fine when cold with the fast idle on,but when the
bike is warm I have to give her a little throttle to start, or she
will stall on start up.Do you have to turn up your idle speed
after doing these mods?My idle is about 1100 to 1200 rpm.Most check tomorrow.


thanks Dober

 

[Scooter]

Try removing the marble. You don't need it with bolt-ons.

 

[HillsRider]

I have the marble mod & don't have a problem starting. Just make sure the idle is set correctly.

<!--EDIT|BusainSD
Reason for Edit: None given...|1144357032 -->

 

[05bulldog]

mine does the same thing...but if we do not need to do the marble thing why does it back fire when coming down from high RPMs when slowing down?? I had been told flames even shoot out from a fellow rider. Since I put the marble in no backfiring or flames! Will setting the idle up help with the stalling?

 

[Stealth_Busa]

Keep the Marble In.

You do not want your bike to backfire, it can blow the head gasket.

Bump up the Idle, if it not at 1100 already, maybe 1200.

Or, you can remove the Pair Valve, put on block off plates, seal off number 4 and be done with it.

Stealth

 

[BusaWhipped]

Your Busa backfires decelerating from high RPM even with the stock exhaust. The stock exhast just muffles it to the point it is not noticable, it doesn't prevent it.

 

[Busa_05]

Some say the perfect jetting, or map for fuel injection, is when you get a bit of backfire on decleration. Not too rich, not too lean. You will lean out in very cold weather though. For instance, I was riding at the end of winter in teens and 20's, and my bike ran...so, so. Backfired a bit, even when at idle, had a few flat spots. But as the season wore on and the temps were consistently in the high 30's and 40's she ran fine. I don't know a whole lot about fuel injection, that is really one of my weaknesses, but I still correlate fuel mixture to my carb'd bikes. I read about these marbles all the time, and every once in awhile some poor sap gets the marble sucked right into his engine. You can buy a stopper made for a purpose just such as this from your local hardware store for .57 cents. It's tapered, so it goes from small end to large end in diameter. I don't know...lots of gusy use the marble, but it just makes me nervous. Anyway, any fuel/air mixture change will change the jetting of your bike. So, you might want to consider that. Setting up your idle won't necessarily "fix" the problem if you've changed the fuel air mixture by putting on slip ons, adding the K&N or BMC air filter, and then blocking off your air box.

Just my .02 cents.

 

[omslaw]

Keep the Marble In.

You do not want your bike to backfire, it can blow the head gasket.

Bump up the Idle, if it not at 1100 already, maybe 1200.

Or, you can remove the Pair Valve, put on block off plates, seal off number 4 and be done with it.

Stealth

Yeah, I wonder if that's what happened to mine! I just got done replacing the head gasket...blown for an unknown reason; 2 tblsp of coolant in #2 cylinder. (hope to have her running this weekend)

Bike backfired like a mofo after putting on my bolt-ons. Removed the PAIR valve and backfire went away.

 

[cosmo]

every once in awhile some poor sap gets the marble sucked right into his engine[/QUOTE]
Strap a small zip-tie just below the marble...done.

 

[Busa_05]

every once in awhile some poor sap gets the marble sucked right into his engine

Strap a small zip-tie just below the marble...done.[/QUOTE]
Get a .57 cent rubber plug made for that purpose. Done.

I'm just batting it back at you in good humor. Lots of fellas do the marble mod and never have a problem, I just choose to do it differently. Obviously the folks that used a marble and ruined their engines didn't do it correctly.

 

[rybraun]

Get the plates.