When I bought my bike in October(95 FXSTC) it came with SE slip on's and the paper work from the previous owner showed a reciept to supply and install a slow jet..How can I tell if it's had the full stage 1 upgrade???Do I need to do single fire ignition or would a big sucker air filter complete the job???

 

Cheers...SParra

Cheers Dave...It does pop quite a bit when you throttle off so I'll check out the jets and breathing and see how it goes...

I can only assume you have the stock CV carby
A jet change is not exactly a carby set-up, any more than an acorn nut makes a custom
If the carby is relatively untouched(not butchered), there would still be tremendous gains in power and response to be made
But you would have to know what you are looking at to ascertain the current situation
If you have the stock air cleaner, any of a range of hi flo type would be beneficial
At one time, I ran a number of the popular ones(scr eagle, kury, etc) on a flo bench, and guess what?
So long as they had a k&n style element, they all flowed pretty well the same
Of course, the bench does not allow for forward motion
The point is that the more economical scr eagle works very much just as well as the more expensive ones, so it comes down more to aesthetics
No one in their right mind would fire a spark plug when it did not need to fire, unless...... they were saving money, and it did not degrade performance overly
The issue is not whether single fire is superior, as a basic understanding of the laws of physics involved answers that question for us
The issue is whether or not you feel that the benefits are worth the money
If you just want a basic good running bike, then that can certainly be achieved with the stock ign system
There will be far more gains to be made in the carby area
I can think of numerous mods to a CV that will all help
1. Correct size pilot jet
2. Set needle to correct height(the earlier sportster needle is popular, but to my view, not absolutely necessary)
3. Modify pumper stop to allow for longer stroke
4. Modify pumper rod to eliminate unwanted pumper operation
5. Polish face of slide(that faces out)
6. Chamfer leadings edges of slide guides(and slide, but be careful, as this area is thin)
7. Correct main jet(big is the go here, as the main jet in a CV does not operate until very high rpm...... relatively speaking)
8. Correct main jet air bleed(making sure the jet entry point is suitably high)
9. Correct slide port
10. Correct slide spring tension
11. Modify emulsion ports main jet tube

I know that is a lot, and you really have to know what you are doing, or else you will almost certainly wreck it(and
there are many trashed CV's out there)

On a stock bike, you can certainly run timing a little more advanced for low end power
If you notice pinging on hitting the throttle, alter the VOES changeover setting

...Thanks Dyna for the info...Maybe in my original post I should have said I'm a plumber...

 

Cheers...Sparra

My intention is to open your eyes up to what can be done
Not to attempt to instruct you how to do it
I do not think that would be possible via this medium anyhow
But now should you choose to get some work done somewhere, and all they offer is a jet change, you can think to yourself,
"hey, theres a lot more than that to it"
Thats why there are so many aftermarket carbys sold, when the stock item is totally capable
Because few have any clue at all as to what to do

Thanks for the info fella's and I wasn't trying to be a smartass Dyna,just got a little confused....From the invoice that was given to me from the previous owner it has a 45 slow jet installed and I just took the carby off and the mixture screw has been drilled out so that has been done...I have just now ordered a S/E stage 1 air cleaner kit so when that arrives

I will see how much of an improvement there is before I order any new jets...Hopefully it won't be too hard to get the mixture sorted and all will be good...Thanks again for the info and the links...

 

Cheers...Sparra

 

the slide needs to be drilled with a number 30 drill, and it is far from pointless
it really is essential when using the standard needle
45 pilot is right on the edge of just being big enough
the idle mixture screw covers much, but the transition ports never lie
1.5 to 1.75 turns out is a rough guideline
any more than that and you are just fooling yourself that the jet is adequate
with a SE a/c, 48 is the go
you can easily go all the way up to 195 main, as the needle exerts control well into the rev range, and even more so when you reset the main air bleed(which is what you want)

and not for a minute did I think anything negative, or that you were being a "smart***"

I know all about those CV carbys, and I love them
they made me look like a real tuning hero in the nineties, when in reality it was the quality of the carby that was really impressive
hope it goes well for you
DR

OK Fella's...The S/E air filter turned up yesterday and I fitted it up...the bike starts and idols as it did before and seems to rev ok...I haven't been for a ride yet but can someone tell me how I can tell if it is running too lean and if it is will this cause a problem for the motor...As I said,everything seems and sounds the same as with the standard fitler at the moment.

 

Cheers...Sparra