How to know if bike has been rejeted?

[dcoffey48]

I bought my 1990 GS500e this summer.  I'm thinking about installing a Jardine exhaust this winter and would need to rejet as well.  What got me wondering if it had already been done by previous owners is that it is running great and the temperature lately has been about 35-40 degrees.  I just twist the choke on to start, let her idle for about a minute, then ride off.  I ride for about another minute then twist the choke off.  I don't seem to have any "cold natured" problems.

Is there an easy way to tell if it has been rejeted already?  Otherwise I will just have to assume that it has not been and rejet anyway.



Thanks,
Dave.

[reminor]

AFAIK, the only sure way is by opening up the carbs, unscrewing jets and looking at the numbers. Judging by what your described I would guess it was jetted. The problem is there are many ways (and jet sizes/washers/etc) the "jetting" can be done.

You can also put it on the dyno and taking measurements. Jetted bikes put out more HPs. Though I cannot personally attest for dyno as I never did it so let other members correct me on that.

If you like the way it rides, let it live. You may open a can of worms trying to fix something which ain't broken...

[The Buddha]

Look for air screw plug caps being removed, then see if the float bowl screws have been replaced by allen or other type heads.
If those are both affirmative, then more than likely its been rejetted. BTW with allen head float bowl screws you can take off float bowls wihtout taking off the carbs off the bike. That means you can look at jets without taking off the carbs.
Cool.
Srinath.

[Kasumi]

Sounds like it will have been rejetted - seems to have removed warm up probs.

But anywhos if your going to install a jardine you will probably need to rejet anyway as adding anything will usually affect the way it runs and require more adjustment. So to recap, it sounds like it runs great now so don't touch it, when you add the exhaust you will probably find you will need to rejet.