Carb rejetting - Page 2

 



Sigwings wrote:

Exactly why would that cause problems?  

cheers

bob

 



more air may lean out the gas.

 

If the bike is backfiring, that is a sign that it is running lean and this
is very bad for your engine. It generates more heat and you could end up
cooking a piston or ???

You can try adjusting the idle mixture screw as it will help at lower rpms.
Once you have it 'just right', take it for a highway run, shut it down and
pull the spark plugs. If they are white it is still too lean and you will
need to reject.

 



It is fairly simple---if you are just opening up the exhaust the intake will
restrict the amount of air that will flow through the carb which keeps it
close to 'stock' so the carb doesn't need changing. Same thing is true if
you only change the air filter, the exhaust will restrict the maximum amount
of air that will flow. BUT if you change BOTH you will be going into a realm
that MamaYama did not allow for in the original carb/jetting setup.
Doing both will give you more available power because the engine doesn't
have to work so hard to suck in air or push it out---leaving more available
horsepower at the rear wheel BUT the increased airflow will be outside the
parameters of the way the engine was set up to begin with which will make it
run lean with all the other problems that go with THAT!
A friend ported his V-Star 1100 engine and intake, put on V&H longshots and
a hypercharger, all at the same time without re-jetting. the bike was
impossible to start, ran like crap when it did and 'blued' his pipes in less
than 300 miles. BUT when he got the jetting done it started better than it
did when new, ran like a striped ass ape AND got better fuel mileage than
stock.
I'd say it is worth the effort.
You can do it yourself, check out www.delphiforums.com there are forums for
Roadstars and V-stars with very knowledgeable people willing to teach ya
how.

 



Khutter wrote:

OK, tnx.  That was what I needed to know.  Guess I'll rejet.

cheers

bob