Author Topic: One step richer?  (Read 6865 times)

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Offline lucky

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Re: One step richer?
« Reply #50 on: September 10, 2012, 08:07:54 PM »
It gets even better, I went by today to swap out the 130's I bought after I realized 125 was too rich and he just gave me dyna jet 118's for free.  Hopefully that is the sweet spot for me.
Dynojet 118's are the same as keihin 125's.
There is a conversion chart between keihin/dynojet/ mikuni available if you google it

Great info Brewsky!!

Offline matt mattison

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Re: One step richer?
« Reply #51 on: September 11, 2012, 03:33:56 PM »
I have been fiddling with the AF screws. I have tried it at .5, 1.0, 1.5, and 2.0 turns out. The bike still had issues maintaining idle and every one (except I didn't get to check .5 cause it was popping so much on the low end I gave up). I think the bike ran best at 1.5 though.

I think what I am experiencing is this: I start out with the idle working pretty well. After I ride a while, it gets progressively worse. As I ride, the over-rich condition fouls up my plugs and makes it tough to drop back down to idle.

I think I am going to move the clip back up to the 4th position and see if that leans it out enough.

BTW, I just bought a 650 cam + tach + tach drive. That shouldn't necessitate a change in jet settings right?
1975 CB550F
2011 MV Agusta Brutale 1090RR

Offline matt mattison

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Re: One step richer?
« Reply #52 on: September 11, 2012, 03:36:40 PM »
Changing the cam will most certainly necessitate a re jet of your carbs. More lift means more air. More air needs more fuel or you will be too lean.
1975 CB550F
2011 MV Agusta Brutale 1090RR

Offline Elan

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Re: One step richer?
« Reply #53 on: September 14, 2012, 04:44:58 PM »
It gets even better, I went by today to swap out the 130's I bought after I realized 125 was too rich and he just gave me dyna jet 118's for free.  Hopefully that is the sweet spot for me.
Dynojet 118's are the same as keihin 125's.
There is a conversion chart between keihin/dynojet/ mikuni available if you google it


holy crap I didn't know they were different! Maybe thats why I'm having trouble jetting!
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Offline lucky

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Re: One step richer?
« Reply #54 on: September 14, 2012, 04:49:24 PM »
Changing the cam will most certainly necessitate a re jet of your carbs. More lift means more air. More air needs more fuel or you will be too lean.

It is not that much more air. Just a tiny bit more.

Offline lucky

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Re: One step richer?
« Reply #55 on: September 14, 2012, 04:50:46 PM »
It gets even better, I went by today to swap out the 130's I bought after I realized 125 was too rich and he just gave me dyna jet 118's for free.  Hopefully that is the sweet spot for me.
Dynojet 118's are the same as keihin 125's.
There is a conversion chart between keihin/dynojet/ mikuni available if you google it


holy crap I didn't know they were different! Maybe thats why I'm having trouble jetting!

Have you even seen Dynojets?
Before you make changes check to see what you have.

Offline Elan

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Re: One step richer?
« Reply #56 on: September 14, 2012, 05:32:21 PM »
It gets even better, I went by today to swap out the 130's I bought after I realized 125 was too rich and he just gave me dyna jet 118's for free.  Hopefully that is the sweet spot for me.
Dynojet 118's are the same as keihin 125's.
There is a conversion chart between keihin/dynojet/ mikuni available if you google it


holy crap I didn't know they were different! Maybe thats why I'm having trouble jetting!

Have you even seen Dynojets?
Before you make changes check to see what you have.

Right lucky, I started changing jets without seeing what I had ::)  WHat do you even mean by that? I have both dynojets and keihins and yes, the outer diameter size is different, but that doesn't mean anything. You can compare old keihins to new keihins and the outer diameter can be different. Its the "jet #size" I am talking about

basically, the jet # signifies the inside diameter of the jet, but I understood it to be a unit of measurement. if the same hole size is a different reference number across brands, then the jet # is just a number, with no relation to measurement- and that is just stupid. Why not just have the same numbering system if they are manufacturing for the same carburetor?

Oil Pump Kits are Available on eBay!See my eBay store!
http://stores.ebay.com/Vital-Motor-Parts?_trksid=p2047675.l2563

k6 build   http://forums.sohc4.net/index.php?topic=79833.0

76 750k