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Idle jets - 1990 California

Dr. Jake

Just got it firing!
Joined
Jul 18, 2018
Messages
23
Location
Copenhagen, Denmark
Hi Guys

My California is running quite well after some tweaking. It is still not as smooth as my V65, even though the carbs are synced and ignition timing spot on (electronic). My issue is that I have to turn the idle mixture screws way out to get proper idle - 3,5 and 4,5 FULL turns respectively?? :wondering:

I have 30mm PHFs. The PO said he cleaned them every year and they did look rather clean inside. I have cleaned them with no change. The jetting is standard with 50 idle jets and 125 mains. I'm not really sure whats going on: I now it used to run fine with standard settings (idle screw out 1,5 turns) but the last couple of years he couldn't get it to run properly and sold it. Now it runs quite OK, but with the extreme settings stated above??:think:
ANy input to whats going on would be appreciated..

I want to get richer jets - but where do I start?? 52? 55? 60?? I am at a loss :):)

Thank you

Jake
 
I would check the mix screw, look at the tip, is it short or long type needle? In USA here we had long type(for EPA) and I ground them down to be size of short ones. Make sure the oring is there also.
If you go w/larger jet it will need less turns out, I'd only go 5 more. If it has a 50 in it chances are you have a richer cut out on the slide like 50/3.
 
I would check the mix screw, look at the tip, is it short or long type needle? In USA here we had long type(for EPA) and I ground them down to be size of short ones. Make sure the oring is there also.
If you go w/larger jet it will need less turns out, I'd only go 5 more. If it has a 50 in it chances are you have a richer cut out on the slide like 50/3.

Hi Steve
It has a long tip - 5mm. Spring, washer and O-ring in place. The slides are 50/3

Thank you

Jake
 

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Do you have access to the short tipped ones like in a older G5? Just to get the tip the correct length. If you use a grinder the tip bends real easy so be careful. I'll go measure short tip.

OK, short tip on a VHB carb is a bit over 2mm, so that's what you want. Long tip I measured is almost at 5mm(EPA needles). When you said they were right at 4 turns I thought long tip, cause that's what it took for them.
In the Guzziology book it has the exact size of tip. I have always used a VHB screw and ground them till they fit 'tip to shoulder' facing ea other.
No one does carbs anymore, so I have lots of carb parts from the hot rod days of gutting airboxes and opening pipes.
 
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I would check the mix screw, look at the tip, is it short or long type needle? In USA here we had long type(for EPA) and I ground them down to be size of short ones. Make sure the oring is there also.
If you go w/larger jet it will need less turns out, I'd only go 5 more. If it has a 50 in it chances are you have a richer cut out on the slide like 50/3.

Hi Steve
It has a long tip - 5mm. Spring, washer and O-ring in place. The slides are 50/3


Do you have access to the short tipped ones like in a older G5? Just to get the tip the correct length. If you use a grinder the tip bends real easy so be careful. I'll go measure short tip.

Thank you!

I still wonder why it has to be turned out so far now.. the manual sats 1,5 turns - no idle possible at all before 3 full turns..
 
OK, short tip on a VHB carb is a bit over 2mm, so that's what you want. Long tip I measured is almost at 5mm(EPA needles). When you said they were right at 4 turns I thought long tip, cause that's what it took for them.
In the Guzziology book it has the exact size of tip. I have always used a VHB screw and ground them till they fit 'tip to shoulder' facing ea other.
No one does carbs anymore, so I have lots of carb parts from the hot rod days of gutting airboxes and opening pipes.
 
Book I have for carbs says 3 turns and more is out of spec for carb. The book refers to short tip screws, like they always used till the lean burn carbs came on them.

Measured short tip at 95 thousands inch or .095"
 
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OK. Maybe I just cut Them. I may even have some short tip ones from a phbh carb lying about - dont know about the lenght though
Still - if you say it may be supposed to be that way, and that 4 turns isnt excessive I could just leave it as it is..

Thanks for all your help

Jake
 
I was having a hard time with my Lemans III setting idle after a broken internal slide cable on the left PHF 36. Idle mixture, sync'd carbs nothing had changed except the internal cables (I changed both sides). Thought I'd bought the wrong length.

I checked the valve lash and found the valves adjusted way too tight, to the point I was losing compression. This affected the vacuum I guess and the carbs then adjusted correctly.
 
I was having a hard time with my Lemans III setting idle after a broken internal slide cable on the left PHF 36. Idle mixture, sync'd carbs nothing had changed except the internal cables (I changed both sides). Thought I'd bought the wrong length.

I checked the valve lash and found the valves adjusted way too tight, to the point I was losing compression. This affected the vacuum I guess and the carbs then adjusted correctly.

I have not yet checked rocker clearance - it does ticker away like I expect though

Still one of the valves could be too tight (I do completely trust the Work of the PO) - I will bump it up on my list

Thanks

Jake
 
4 turns is out of range. 3 would be max for PHF, that's why trim the tip. The ones in a VHB work. I used a magnifying glass to get the tip nice w/file.
 
Once you get the mix screw squared away and if you think it is still too far out I've had good results installing 52 pilot jets. They seem to be just about right and the settings become spot on and transition to the next circuit (atomizer/needle) seems better.
 
Once you get the mix screw squared away and if you think it is still too far out I've had good results installing 52 pilot jets. They seem to be just about right and the settings become spot on and transition to the next circuit (atomizer/needle) seems better.

I do have some intake backfire when opening the throttle part ways. The PHFs have accelerator pumps making it hard (for me ) to evaluate the transition

Jake
 
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