Re: Backfiring '94 R11RS

[Karl Johnson <karljohnson@xxxxxxxxxxxxx>]

One time, on my '94 R1100RS, a tiny pebble got wedged in the right  
hand throttle body pulley, under the cable. It caused some  
interesting symptoms.

It caused the throttle bodies to be out of sync...which I corrected a  
idle and low rpms, but it was impossible to balance them at midrange  
rpms (where the pebble interfered with the cable). The bike would  
stumble and backfire when decelerating in the midrange.

I happened to see the pebble while I was looking for an intake  
leak...thinking that was the problem.

One time the dealer only finger-tightened one of the sparkplugs after  
a tuneup. That caused some backfiring too.

The nuts bolting the exhaust pipe to the head were loose one time.  
That was long ago, but I seem to remember that caused some backfiring.

There's also the possibility the throttle body butterfly valve shafts  
are worn and you've got an intake leak there...
http://largiader.com/tech/tb/

Let us know what you find.

Karl

On Jul 14, 2006, at 8:04 PM, Sam S. wrote:

> check the following
>
> - TPS
> - the throttle stop nuts
> - throttle sync
> - exhaust leak
>
> my 99RT did that but once I corrected my TPS, the backfire stopped.
>
> Then again, you can also view the backfire as sure way to stop anyone
> tailgating you bike :)
>
>
> Wayne Woodruff wrote on 7/12/2006, 8:39 PM:
>
>> On Wed, 12 Jul 2006 11:44:21 -0600, you wrote:
>>
>>> Friends,
>>> When deccelerating in 2nd and 1st the engine will backfire or cough
>> between 3k
>>> and 2k rpm.  What is causing this?  And what's the remedy?
>>> Thanks,
>>> Murali
>>>
>>
>> 1) Did this recently start or has it always done this?
>>
>> 2) did you change anything recently?  Any maintenance, adjustments,
>> etc?
>>
>> Wayne Woodruff
>> http://www.2zars.com

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