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V50 carb question

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iansoady View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote iansoady Quote  Post ReplyReply Direct Link To This Post Topic: V50 carb question
    Posted: 14 Nov 2017 at 12:38
I've just been rebuilding the carbs on my V50. It has 26mm VHB carbs fitted instead of the standard 24mm. All jets etc conform to the spec in the Guzzi workshop manual.

My only query is that the needles were in the bottom (of three) grooves rather than the middle as stated in the manual.

It's fitted with fake K&N air filters. When I had it on the road, it did feel to me as though it was running a little rich.

I've replaced them in the top groove as specified. Any views?
Ian
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Brian UK View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 14 Nov 2017 at 13:56
Is it a V50 II or III?
The II had 24mm carbs, the III had 26mm.
 
Running the needle in the bottom groove will make it run rich, but where have you put it now? You say middle is what is in the manual, but you have put it in the top one "as specified"??
Brian.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote iansoady Quote  Post ReplyReply Direct Link To This Post Posted: 14 Nov 2017 at 16:04
Sorry I did mean I've put it in the middle. Slight brain fade.......

It is a V50 II although something of a mongrel, starting its life as a V35.
Ian
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Mike H View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike H Quote  Post ReplyReply Direct Link To This Post Posted: 14 Nov 2017 at 17:19
if the filters are the little cone shaped type it's possible it's running rich at & near wide open throttle because the filters are actually restricting air flow.

If were me I would get all carb settings back to stock and go from there.

Usually all that's needed if indeed the filters are less restrictive than stock, is to increase main jet one size step.

HTH

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Post Options Post Options   Thanks (0) Thanks(0)   Quote c13pep Quote  Post ReplyReply Direct Link To This Post Posted: 14 Nov 2017 at 19:56
Having just got thro` my own carb difficulties with the V50/3 I found that running without filters during set up was the way to go and only refitting non restrictive ones once I was happy with performance. Renewing all the jets etc. made set up easier, in my case the main jet was increased from 118 to 130 with all the rest stock. Your oversized carbs may just require a little more patience!!
CHRIS
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 14 Nov 2017 at 20:20
As you have slightly larger choke carbs than standard, what have you done to avoid the step between them and the manifolds and then inlet ports?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote iansoady Quote  Post ReplyReply Direct Link To This Post Posted: 15 Nov 2017 at 10:59
There doesn't seem to be a step Brian, I assume the rubber connectors came with the carbs.
Ian
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 15 Nov 2017 at 17:47
On mine the manifold was certainly 24mm, and it actually tapered towards the inlet port, giving a step there. So you will have a reduction from the carb to the port.
I opened up the manifolds on mine to make them parallel though doubt it actually made much difference. Though when you have 26mm carbs it might help a bit if everything is smooth  and flows inside.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote iansoady Quote  Post ReplyReply Direct Link To This Post Posted: 16 Nov 2017 at 11:07
I'll check it out thoroughly before final fitting.
Ian
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