Author Topic: Main Jet Recommendation for CB550 with Mods  (Read 1451 times)

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Offline Cut

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Main Jet Recommendation for CB550 with Mods
« on: March 26, 2013, 07:29:43 PM »
Just finished rebuilding the top end on my 75 CB550K1 and am looking for anyone who is running a similar setup to mine to chime in and let me know what jetting is performing well so that I can save time/money dialing her in with the modifications that I have made since the rebuild.  My configuration is as follows:

650 Cam
Steel Dragon Velocity Stacks
4 into 2 Exhaust (Jardine)

Everything else is stock.  Thanks in advance!
1975 CB550k1 (Hot Wifes Ride)
2012 BMW F800GS
1968 CB450 Bomber (Restoration Project)

Offline dave500

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Re: Main Jet Recommendation for CB550 with Mods
« Reply #1 on: March 27, 2013, 12:31:04 AM »
run the stock jets first and go from there,the stacks might cause some sorting by themselves.

Offline Cut

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Re: Main Jet Recommendation for CB550 with Mods
« Reply #2 on: March 27, 2013, 12:25:31 PM »
Mike from Steel Dragon Performance stated that his clients are reporting that 115 mains are working well for them on the CB550. 
1975 CB550k1 (Hot Wifes Ride)
2012 BMW F800GS
1968 CB450 Bomber (Restoration Project)

Offline dave500

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Re: Main Jet Recommendation for CB550 with Mods
« Reply #3 on: March 27, 2013, 12:35:41 PM »
your results may vary,start with the stock jets and go from there,yours might only need a more subtle increase in jet size,some people think their bikes run great but theyve missed the mark and they run #$%*.
« Last Edit: March 27, 2013, 12:38:34 PM by dave500 »

Offline lucky

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Re: Main Jet Recommendation for CB550 with Mods
« Reply #4 on: March 27, 2013, 01:22:30 PM »
With velocity stacks I would go up on the main, and lower the clip on the slide needle one notch.

Offline Cut

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Re: Main Jet Recommendation for CB550 with Mods
« Reply #5 on: March 27, 2013, 04:43:54 PM »
Copy all and will have 100s/105s/110s and 115s at the ready.  Will drop the needle jet a notch if I get a drop in performance in the mid-range.  I think dropping the needle a notch is recommended anyhow.  Will post back in a day or two.  Kudo's!
1975 CB550k1 (Hot Wifes Ride)
2012 BMW F800GS
1968 CB450 Bomber (Restoration Project)

Offline dave500

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Re: Main Jet Recommendation for CB550 with Mods
« Reply #6 on: March 27, 2013, 10:42:30 PM »
do one change at a time!!say swap the main jet but dont touch the needle yet,,this is where people get it so wrong!they start twidling everything at once.