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Tony G View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Tony G Quote  Post ReplyReply Direct Link To This Post Posted: 26 Jan 2021 at 20:00
Well the throttle cable too the right hand carb, goes over the the frame. I'd prefer under. I'm getting sidetracked. The cables have a bit af slack, It'll be me not turn out enough. theyer turned out 3 and a 1/2 turns to get too 2000 reves so I'll take it theres plenty to go.
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Richard Hyatt View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Richard Hyatt Quote  Post ReplyReply Direct Link To This Post Posted: 26 Jan 2021 at 20:21
OK,
If, whenever you are able, can you establish if the slides go right down and close off the venturi?
Mirror and torch job or remove carb again.
If you start with the venturi closed right down then slowly turn the tickover screws to see when the upward movement starts.
At least you can see how many threads you have left.

I assume you have no air leak holding the tickover up?
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Tony G View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Tony G Quote  Post ReplyReply Direct Link To This Post Posted: 26 Jan 2021 at 20:39
None I'm aware of. I'll take the other one off tomorrow, and get back to you.
     thanks
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Tony G View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Tony G Quote  Post ReplyReply Direct Link To This Post Posted: 26 Jan 2021 at 20:42
Good advice Richard thank you
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Ken-Guzzibear View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Ken-Guzzibear Quote  Post ReplyReply Direct Link To This Post Posted: 26 Jan 2021 at 20:53
when i had vhb carbs lifting the throttle then dropping it i could hear the slides click you will hear a click click if they are not in sync, old trick was to remove the air intake use strip of paper to see when the slides open .... but you can actually hear the slides clik ..... at least you can get them the same before you start it and then play with stop screws 

It can take an awful lot of patience to get carbs set up but very satisfying when it all works well
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 26 Jan 2021 at 21:49

This might be of some help when setting up the carbs.

Brian.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote iansoady Quote  Post ReplyReply Direct Link To This Post Posted: 27 Jan 2021 at 11:35
They are all different. My V50 needed choke starting from cold even in warm weather but would start 8 stroking after about 10 seconds when I could turn the choke off completely.

I fouind carbtune was the best way of synchronising.
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Tony G View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Tony G Quote  Post ReplyReply Direct Link To This Post Posted: 27 Jan 2021 at 20:16
Thanks Everyone. Took the carbs off today. All jets ok. float height ok. looked at carb piston masif difference. So wound tick over screws in all the way. eaven by eye, the left hand carb piston gap was twice as wide as the right. wound both tick over screws out 1 1/2 turns. Right carb 1mm left 2mm. ended up turning left another 1 1/2 turns to match them up. Plenty of slack in cables I'll fit them tomorrow if I get a minuet. Grandad duties.
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Tony G View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Tony G Quote  Post ReplyReply Direct Link To This Post Posted: 27 Jan 2021 at 20:24
That's the next thing to buy Ian a carbtune. Ive got a vaccume style one with the needles. But the holes are to big for it Cry
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 27 Jan 2021 at 20:44
A simple oil or water manometer is the simplest, most reliable method of synchronising two carbs. Probably the most accurate too.
Brian.

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Tony G View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Tony G Quote  Post ReplyReply Direct Link To This Post Posted: 27 Jan 2021 at 21:08
Gr8. thanks Brian.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Richard Hyatt Quote  Post ReplyReply Direct Link To This Post Posted: 27 Jan 2021 at 21:14
As someone said earlier, when you get the carbs  back together and with both throttle cables fitted - I suppose you don't even need them fitted to the engine to enable you to see the slides going up and down.
You can then look into the inlets of the carb and see what daylight you have by screwing the screws.
You could even adjust the cable adjuster to get a uniform CLUNK  together from both carbs.

Then carb tops off and refit everything to the bike , reconfirming the CLUNKS.

Just a thought, is it possible to replace the slides into the carb but the wrong way round if you know what I mean?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Tony G Quote  Post ReplyReply Direct Link To This Post Posted: 28 Jan 2021 at 08:23
checked that one Richard no, they'll only go one way.
  
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dave P. Quote  Post ReplyReply Direct Link To This Post Posted: 28 Jan 2021 at 10:07
Have you checked to see if the slides are very worn where the throttle stop screws contact them. You can swap the slides over, carb to carb which unless it has been done before gives a new unworn contact for the throttle stop screw to touch. And are both throttle stop screws the same length? Do the throttle slides both have the same cutaway?

Edited by Dave P. - 28 Jan 2021 at 10:20
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Ken-Guzzibear Quote  Post ReplyReply Direct Link To This Post Posted: 28 Jan 2021 at 11:58
I find the carbs need a steady hand and patience to set them up . Setting them for tick over with cool engine will often cause much higher revs at tick over when hot. I found that once hot a tiny turn on the throttle screw is all that is needed. The first time i did this I got SO frustrated , had a sense of humour failure there was much shouting and cussing .... took me till next day to go back to it ...You are not alone ... Once sorted the deep joy is well felt ....
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