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Stell
Best to open up the carbs. You could have wrong slow and mains jets but the only way to know is to open it up. If it has sat for any length of time they may be clogged up some. So open it up and clear everything out note the sizes and go from there. Also check the needles and make sure they haven't been changed as well.
 

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Stell
2 and 3 are fat (Rich) what mains and pilots do you have in there?
I have checked spare parts for my bike at cmsnl.com and according to their list I should have #145 on all four and pilot #42 and the same needle as all other except California. I wonder why my bike have larger and equally sized main jets? Is our petrol that different? It would be interesting to know more about this.
I have changed the oil and filter now. The old oil is really smelling of petrol! I will not drive until I checked both compression of all cylinders and cleaned the carbs.
 

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US jetting has inner cylinders larger than outer. I don't have access to my FSM. I will check it tonight when I get home.
 

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Honda Factory Service manual I have states 1 and 4 are 140 and 2 and 3 are 142 with a 42 slow jet. needles should be J5FZ's. Judging by the color of those plugs i'd switch them the these numbers.I think you'll find it will help out.
The rest of the info states
2 3/4 turns out initial on the idle screws.
Float level 13.7mm (0.54 in)
 

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I've ordered repair kit for carbs and petcock, I'll check which jets I have present in my carbs. Then I'll decide what to do when I have more facts. The repair kit will for sure have a different set of jets compared with my carbs! :)
I will report back here when I know more.
 

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Hi
Here's an update of my troubles.
I have replaced all four floater needles and the floater gasket. The needles where not very noticable worn out, just barely showed a thin line around them. But I think it needed to be done.

As I suspected there where #145 jets on all four carbs. They are still there, I have not replaced them, but I am thinking about it. The rebuild kit contained the US jets, 2x #140 and 2x #142.
I will first get it running on 95 octane instead of 98 that I have been using and then get the air/fuel screws adjusted. After that maybe considering changing jets.

One thing I noticed when I were going to put the carbs back, is that it is a bit hard to get a perfect fit at the intake manifold and with the airbox. It required a fair bit of wriggling back and forth before I got that tight. (This could be one of the things that made the bike stink of petrol, I may have been missing this when I open up this part the first time!)

I am still waiting on the petcock replacement parts. The first one was mislabeled on the ebaystore I bought it from, so the part I got was for an other bike which were almost working in my setting, spent two hour tying to get it to work before I realised that it was the wrong part! :-/ They where nice and gave me a refund, but it's APITA to be waiting for slow deliveries, again.

So at the moment it smells a bit of petrol, but not that much as before! But I think it's on it's way to be fixed.

I will be posting updates as soon I know more. It will be a long writeup after this is fixed... :)
 

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Hi
Here's an update of my troubles.
I have replaced all four floater needles and the floater gasket. The needles where not very noticable worn out, just barely showed a thin line around them. But I think it needed to be done.

As I suspected there where #145 jets on all four carbs. They are still there, I have not replaced them, but I am thinking about it. The rebuild kit contained the US jets, 2x #140 and 2x #142.
I will first get it running on 95 octane instead of 98 that I have been using and then get the air/fuel screws adjusted. After that maybe considering changing jets.

One thing I noticed when I were going to put the carbs back, is that it is a bit hard to get a perfect fit at the intake manifold and with the airbox. It required a fair bit of wriggling back and forth before I got that tight. (This could be one of the things that made the bike stink of petrol, I may have been missing this when I open up this part the first time!)

I am still waiting on the petcock replacement parts. The first one was mislabeled on the ebaystore I bought it from, so the part I got was for an other bike which were almost working in my setting, spent two hour tying to get it to work before I realised that it was the wrong part! :-/ They where nice and gave me a refund, but it's APITA to be waiting for slow deliveries, again.

So at the moment it smells a bit of petrol, but not that much as before! But I think it's on it's way to be fixed.

I will be posting updates as soon I know more. It will be a long writeup after this is fixed... :)
Quick suggestion to add to your good work - DON'T overtighten the carb mount rubbers - there should be about 11mm between the two faces of each clamp when tight.

Overtightening can distort the rubbers and cause more leaks.
 

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Quick suggestion to add to your good work - DON'T overtighten the carb mount rubbers - there should be about 11mm between the two faces of each clamp when tight.

Overtightening can distort the rubbers and cause more leaks.
Thanks for the heads-up, I think I'm not overtightening. I have tried to keep it as they say in the manual, 11-13 mm. Although 13 mm IS to loose on my bike, the rubbers are not sitting tight at all when 13 mm and does not stay in place. I'm really thankful for all suggsestions, because it's really easy to miss something when one is new to doing a thing like this! :think:
 

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Yesterday had a day on the open road, no city or any kind of slow traffic, touring around, sometimes lively sometimes wafting, 6.3L/100 aka 45 mpg
 
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