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carlo
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Having 2 threads about the same issue doesn't help things.

I have locked this thread.

Opps. I messed up here. I have unlocked this thread, as it has the history and replies on it, and locked the one that was just started.

Carlo, got your PM and my mistake. Sorry.

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If the 250 virago is the same set up, it looks like their is a filter assmebly on the bottom of the tank, with seperate feeds for normal running and reserve, the filter screens will be inside the tank and may be gunged up. You should also be able to strip the fuel cock and check thats clean inside. Check that the tank vent is clear.

Looks like 2 pipes then connected to the pump, Im guessing one is vac to operate the pump the other feeds to the carb. Check the pipes are connected the right way round and are not pinched, also check the same with the 2 pipes from/to the fuel cock and fuel filter for right way round and cock in right position

Check the pipe connection from the pump to where its fixes on the engine unit, make sure no pinching or leaks

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If the 250 virago is the same set up, it looks like their is a filter assmebly on the bottom of the tank, with seperate feeds for normal running and reserve, the filter screens will be inside the tank and may be gunged up. You should also be able to strip the fuel cock and check thats clean inside. Check that the tank vent is clear.

Looks like 2 pipes then connected to the pump, Im guessing one is vac to operate the pump the other feeds to the carb. Check the pipes are connected the right way round and are not pinched, also check the same with the 2 pipes from/to the fuel cock and fuel filter for right way round and cock in right position

Check the pipe connection from the pump to where its fixes on the engine unit, make sure no pinching or leaks

Hi

All the hoses are ok and I cleaned the filters when i draind the tank. As I said after removing the aircleaner if you block the air cleaner intake hole with my hand whilst it is ticking over and then reving the bike as I remove my hand and it revs up to the max for 5 seconds then drops back to the normal tickover, did this about a dozen times but if I don't have my hand over it and then removing it as I rev it still reverts to not being able to rev, just cuts out when you try and rev it.

I can'think that it is anything else other than a blockage in the carb somewhere as by blocking the aircleaner it is making the mix richer and also causing the carb to poss, suck harder and forcing the mix through the parcial blockage, what do you think?

Thanks

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Can anyone help, I have a virago 125 year 2000 that hassat in a garae for 12 years with only 869 on the clock..

The owner had a prob, ith only running on 1 cylinder so took it to the garage, they changed the carb, the pump and all the hoses, but it was still the same.

It will start but only on full choke and then if you rev it it will cut out straight away, will not start with no choke.

Have replaced the petrol and battery, and there is no knocking etc, from the engine or smoke, has a good spark on both plugs and comp, is ok on both cylinders.

Any ideas anyone

Thanks

Right then, back to basics

Put it all back together, check that the choke is adjusted correctly

"IT WILL START BUT ONLY ON FULL CHOKE"

Thats ok. Start it from cold, leave it ticking over, gradually close the choke over 5 minites or so, dont rev it. Aftre 5 minutes, the choke should be closed and the bike now warmed up and ticking over on both cylinders. Tickover should be around 1000 to 1250 rpm, if it isnt then adjust it on the throttle stop screw till it is

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Right then, back to basics

Put it all back together, check that the choke is adjusted correctly

"IT WILL START BUT ONLY ON FULL CHOKE"

Thats ok. Start it from cold, leave it ticking over, gradually close the choke over 5 minites or so, dont rev it. Aftre 5 minutes, the choke should be closed and the bike now warmed up and ticking over on both cylinders. Tickover should be around 1000 to 1250 rpm, if it isnt then adjust it on the throttle stop screw till it is

Hi

Thanks for your reply.

If you read through what I have tried you will see that it is not that simple, the latest, having after done everything inc, stripping and cleaning the carb 5 times, checking filters, new fuel, is as I have said, after removing the aircleaner if I block the air cleaner intake hole with my hand whilst it is ticking over and then I rev the bike as I remove my hand it revs up to the max for 5 seconds then drops back to the normal tickover, did this about a dozen times but if I don't have my hand over it as I rev, it reverts to not being able to rev, just cuts out when you try and rev it.

I can't think that it is anything else other than a blockage in the carb somewhere as by blocking the aircleaner intake it is making the mix richer and also causing the carb to poss, suck harder and forcing the mix through the parcial blockage, what do you think?

Thanks

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Hi

Thanks for your reply.

If you read through what I have tried you will see that it is not that simple, the latest, having after done everything inc, stripping and cleaning the carb 5 times, checking filters, new fuel, is as I have said, after removing the aircleaner if I block the air cleaner intake hole with my hand whilst it is ticking over and then I rev the bike as I remove my hand it revs up to the max for 5 seconds then drops back to the normal tickover, did this about a dozen times but if I don't have my hand over it as I rev, it reverts to not being able to rev, just cuts out when you try and rev it.

I can't think that it is anything else other than a blockage in the carb somewhere as by blocking the aircleaner intake it is making the mix richer and also causing the carb to poss, suck harder and forcing the mix through the parcial blockage, what do you think?

Thanks

This sounds like a reasonable assumption, if I were you I'd be sending my carb off somewhere for ultrasonic cleaning.

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forgot to add it has a new air filter as well, also does the same thing with the air filter removed. Theres no prob, with the clutch or side stand switch either. Will engage gear when ticking over on the choke (won't start or tick over without the choke out) and will pull away when clutch let out, but without revs as it will cut out if you just twist the throttle a tiny bit.

I'm thinking this has to be carb, prob, even though they changed the carb, ay ideas anyone!

BTW did you oil the filter like you should have done?

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BTW did you oil the filter like you should have done?

if you mean the air filter it was a new one put on by the garage of the previous owner and still looks like new and it has oil on it.

I think I will go with a new carb, can get a proff, rebuilt carb for £60 so think this will be the easiest and sure way to know.

Thanks for your replies

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reading through this thread make me wonder is the slide moving up when your trying to rev it up,it's a vac carb and if the diaphram is not sealed properly then by putting your hand over the inlet your creating a bigger vac for the slide to work

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reading through this thread make me wonder is the slide moving up when your trying to rev it up,it's a vac carb and if the diaphram is not sealed properly then by putting your hand over the inlet your creating a bigger vac for the slide to work

Hi

Diaphram is new and sits fine, as is all the inside of carb, jets, slide, needle etc, the previous owner put a diff, carb, on it, as I have the old carb, in bits in a bag, but think they put a replacement carb, not new but changed the inside of it with new parts. Have ordered a new carb, and if that don't work I have no idea what it could be. My mate a mechanic had a look at it yesterday and came to the same conclusion as me, in that it can only be something to do with the carb,but thanks for your suggestion.

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Different bike, same symptom

My auld Speedtwin had that same issue. I had stripped and u/s cleaned the carb. When I started it it would tick over but cut out when attempts to rev it. When I had reassembled it, I had put the needle in the wrong setting. Reset it and problem solved.

There is an auld saying that 90% of all 'carb' faults are electrical and 90% of all 'electrical' faults are carb related so dont get fixated on the carb

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Different bike, same symptom

My auld Speedtwin had that same issue. I had stripped and u/s cleaned the carb. When I started it it would tick over but cut out when attempts to rev it. When I had reassembled it, I had put the needle in the wrong setting. Reset it and problem solved.

There is an auld saying that 90% of all 'carb' faults are electrical and 90% of all 'electrical' faults are carb related so dont get fixated on the carb

Hi

I only wish you were right, looked at that and it is correct setting, wish it wasn't LOL, have ordered a carb now, but thanks for yur suggestion

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