New to group, but would like to offer up my $.02 worth.
If you are getting backfire in the exhaust during Deceleration along
with a poor or rough idle it is likely to be an over rich condition.
The backfire, through the exhaust, is the unburnt gas exploding in the
hot exhaust system. If the bike sat through the winter some of the
fuel that remained in the carb may have varnished and built up on the
fuel inlet valve seat resulting in a small leak and over filling the
float bowl a bit. In another note you say it cleared up after a while.
Check the carb for dirt or other stuff. THere's a slim chance a
partially sticking "auto bystarter" could be causing a rich fuel mix.
When the backfire is through the carb a lean condition exsists. The
cylinder is running hotter than normal as there is not enough incoming
fuel/air mix to cool the intake valve down. The lean mixture ignites
prior to getting in the cylinder. Backfire through the carb is not as
loud as it is mutted by the air filter and enclosure. It could lead to
a fire though....
Prior to removing the carb, but sadly after removing a fair amount
of bodywork, have your scooter idling and squirt some WD-40 up at the
intake manifold.(Carb insulator) Once or twice at the point whre the
carb meets the manifold and again at the point where the manifold
meets the head. If the idle changes as the result of one of these
shots it will indicate an air (vacuum leak) at either of these areas
or a crack on the insulator itself.
I hope this helps you out a bit. I used to work on cars as a hobby
in my former married life and now I mainly do woodworking as my hobby.
I'm also happy to report that I got my Honda Service Manual yesterday.
But these bikes are pretty reliable so I may not get to use it.
Have a nice weekend.
--- In CH250HondaElite@yahoogroups.com, "Larry" <MoPedLar@e...> wrote:
> I took my '85 Elite 250 out for a ride today. Everytime I would slow
> down, the bike would backfire. Sometimes it would let out 2-3 small
> backfires before coming to a stop, and sometimes jus one big
> backfire. I had a similar problem last fall, but I replaced the
> packing inside the exhaust and that seemed to cure the problem. My
> idle also seems to "skip a beat" now as well.
> The bike has less than 2K miles on her. What could be the problem?
> The bike was tuned up last fall. It has a brand new spark plug and