cafed650 time to jet spot on!

Here ya go!

wiredgeorge wrote:

The barrel jet with the #50 is OVER the pilot jet. It doesn't really have a whole lot of effect on the operation of the pilot jet which has a MUCh smaller hole and is really what controls fuel to the pilot circuit. With your set up, I would use #102.5 main jets and a #15 pilot jet (which is under the #50 jet). The #15 pilot jets are the stock size. I am not sure which jet needle you are using but it likely wouldn't hurt to clip to the 4th slot. The K&N drop in filter and 4 into 1 likely don't flow much more air than a stock filter and pipes. MOST 4 into 1 pipes actually don't flow much better, if at all, than the stock system.

will give that a shot and post back up...thanks WG

so where is the best source for jets?

z1 enterprises

Have bought from Jeff many a time but didnt see em online...will email him

The jets aren't listed if you search by bike model at z1enterprises, I just type "jet" or "pilot" or "main" into the search box on top and it usually gets you to the jets you will need.

I just got in larger pilots from z1 for my 650 (4-1, pods) and I think once I get these in everything should be perfect so I will let you know my setup. I did take the #50's off.

wiredgeorge wrote:

The barrel jet with the #50 is OVER the pilot jet. It doesn't really have a whole lot of effect on the operation of the pilot jet which has a MUCh smaller hole and is really what controls fuel to the pilot circuit. With your set up, I would use #102.5 main jets and a #15 pilot jet (which is under the #50 jet). The #15 pilot jets are the stock size. I am not sure which jet needle you are using but it likely wouldn't hurt to clip to the 4th slot. The K&N drop in filter and 4 into 1 likely don't flow much more air than a stock filter and pipes. MOST 4 into 1 pipes actually don't flow much better, if at all, than the stock system.

So I have yet to investigate what clip position the needle has but the jetting info you gave is exactly what I am running right now.

Some more info that I have on how the bike was running before I pulled the carbs. When ever a lot of throttle was given the bike would bog or if the throttle was bliped the bike would bog down if not die. the bike would run great from about half throttle onward but the bottom end was lacking.

I will find where the clip is on the needle and get back.

Thanks WG

Are you sure of your timing? I was having the exact issue you're describing on my 77 and it was mostly caused by the timing being off. After I got the timing set it was a matter of dinking just a bit with the airscrews to get it dialed in, no jetting change needed. Just throwing that out there...

anarki650 wrote:

Are you sure of your timing? I was having the exact issue you're describing on my 77 and it was mostly caused by the timing being off. After I got the timing set it was a matter of dinking just a bit with the airscrews to get it dialed in, no jetting change needed. Just throwing that out there...

Pretty sure my timing is spot on...new points and condensers timed with a craftsman timing light.

but you never know human error is rampant.

This is a great thread and has got me thinking....

Is it normal to have strong differences in performance that require carb tweaking over the span of a few hours.

Sometimes, after a great ride in before work, after work I can only get my bike to run smoothly by adding choke. :huh: Normal???

I believe that I need to delve in to my carbs as well is all.

Any more thoughts?

scumbag wrote:

So I have yet to investigate what clip position the needle has but the jetting info you gave is exactly what I am running right now.

Some more info that I have on how the bike was running before I pulled the carbs. When ever a lot of throttle was given the bike would bog or if the throttle was bliped the bike would bog down if not die. the bike would run great from about half throttle onward but the bottom end was lacking.

That EXACTLY describes how mine ran after adding new headers. The fix: lower the clip on the jet needle to give maximum richness.

Understand why: from about "1/2 throttle up" the piston raises fully and the needle is all the way up and not restricting or metering flow. The amount of fuel is determined mainly by the size of the main jet.

But, at lighter throttle openings where the piston is only partly raised, the position of the needle with respect to the piston has a HUGE effect on fuel flow.