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xvs running problems


dan28
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i ve bought a 51 plate xvs dragstar as an unfinished project it starts up first time an when not in gear it revs really well when twist the throttle

however once it in gear as soon as you twist the throttle its as though there is no power there it hardly moves the only way it will ride is if you ride the clutch

i ve stripped an cleaned the carb ,the carb is made by mikuni is this the standard carb or has someone fitted a different carb

when out of gear it crackles an pops a little through the exhaust(baffles are removed) so i guess its running rich ? an the carb is putting too much fuel in thats why it wont ride ?

however there is no mixture adjustment screw on the carb tried turning the idle up an down but its still the same

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i ve bought a 51 plate xvs dragstar as an unfinished project it starts up first time an when not in gear it revs really well when twist the throttle

however once it in gear as soon as you twist the throttle its as though there is no power there it hardly moves the only way it will ride is if you ride the clutch

i ve stripped an cleaned the carb ,the carb is made by mikuni is this the standard carb or has someone fitted a different carb

when out of gear it crackles an pops a little through the exhaust(baffles are removed) so i guess its running rich ? an the carb is putting too much fuel in thats why it wont ride ?

however there is no mixture adjustment screw on the carb tried turning the idle up an down but its still the same

get your baffles back in first before making any carb adjustmnts, with the baffles out the engine will breath differently (running rich) which is making the crackles and bangs

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"Failte" dan28, to the YOC club. rolleyes.gif

Im not really familar with your Drag but !

It could be many small things !

It probably is runing a bit ritch but it should at least take off spluttering down the street.

I wonder is it pulling enough air through the filter.

Then I would start at the tank and work my way to the carb again. If all was ok and the carb was working properly then I think you will have to

mess-about with the jets to recorrect the over-ritchness But sit tight till some of the other lads come on that know your bike !

Now that Ive re-read this--- im not much help atall to night

Good luck mate !

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get your baffles back in first before making any carb adjustmnts, with the baffles out the engine will breath differently (running rich) which is making the crackles and bangs

thanks for the replys

fzr al

i m from near leeds too :D

i dont have the baffles it came to me with them removed

it cracles when revved in neutral but once in gear it will hardly go at all it loses power from some where

i ve turn the idle speed up an down but it doesnt help

would you say its fuel related

or something else like maybe a sensor or coil ?

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thanks for the replys

fzr al

i m from near leeds too :D

i dont have the baffles it came to me with them removed

it cracles when revved in neutral but once in gear it will hardly go at all it loses power from some where

i ve turn the idle speed up an down but it doesnt help

would you say its fuel related

or something else like maybe a sensor or coil ?

sound like carb related problems maybe worth getting a carb repair kit I think they are round about £12.00 /£15.00 on evil bay or a second hand carb to try first before looking at coil etc , is it ticking over ok when started, not familar with your bike but is your battery fully charged my KH400 runs crap if the battery is not fully charged it will cough and splutter and drop down on to 2 cylinders then back on to 3

it obviously been rejetted if the baffles have been taken out , but the coil could be breaking down under load have you any spares you can chop and change

Ps i dont think you have mentioned what CC this is

where about in leeds are you i may be able to pop over

cheers Al

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I doubt its electrical. If it starts and tries to rev the pick up coils are doing their bit. You can do resistance checks on them, or if they are Hall effect there's a test box you'll need to see if they are working.

A rich mixture will stop the engine reving - dead. Like hitting the kill switch, if the mixture is that far out.

You will need to change jets in he carb, the adjustments on the carb, needle height and idle mixture- only trim and don't have enough scope of adjustmnet for seriously out of spec mixtures.

Get the exhaust sorted first and find soemone who is experienced setting up carbs

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I doubt its electrical. If it starts and tries to rev the pick up coils are doing their bit. You can do resistance checks on them, or if they are Hall effect there's a test box you'll need to see if they are working.

A rich mixture will stop the engine reving - dead. Like hitting the kill switch, if the mixture is that far out.

You will need to change jets in he carb, the adjustments on the carb, needle height and idle mixture- only trim and don't have enough scope of adjustmnet for seriously out of spec mixtures.

Get the exhaust sorted first and find soemone who is experienced setting up carbs

the bike is at my mates in allerton bywater just ouside castleford its about 10 mile from leeds centre

its a 125

when i bought it the guy said he had been building for 4 years it has sachs forks an back end converted to single seat it looks like something of american chopper lol

he also told me it had a new carb fitted so i reckon either he knew about the problem an fitted a new carb to cure it or he has fitted a different carb an that is causing it

when i bought it was raining but it kept cutting out as it v twin it took ages to warm up (there was no choke cable fitted at the time but there is now )

he said he had rode it to work an it showed on the odemeter it had done 8 mile so at some point it did work

i d rather leave the exhaust to be honest the baffles have ben removed an its been welded up

it doesnt sound that bad to be honest i probably made it sound worse than it does it only crackles when it idling an you give it full revs on tick over it doesnt crackle at all

as i said out of gear you can rev it all day once in gear an you try to ride it just kinda bogs down an there is no power there but its fine when reved on idle

is there a way to check the coil if i put multimeter on battery when its idleing an then again while in gear if the reding is a lot lower will that mean the coil is breaking down underload?

its not the battery

even tried it without the battery fitted

actually thinking about it you can bump it off with out battery an the light work is the normal or the previous owner modifided the wiring if thats the cause maybe the lights are taking the power away from the coil

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A then, I dont think this is as bad as I first thaught.

So its an air cooled 125.

The bike would start and the light would work without the battery.

I also dont think it is a electrical problem. It starts, it idles and revs good (just not in gear)

Maby the guy cut out the baffles and then never rode it since and hence he might not of set up the carb to allow for the changes.

In any case, I think the prob is with the carb. I think the main jet needs to be sorted, this is where the power comes from when you open the throtle,

it will rev up ok in neutral probably because it is short blasts of throtle and is not having to use the main jet (still on pilot jet)

I dont think its a big job to do but If your not comfortable working on the carb (little to be gained by messing with it) take it to your local bike shop and tell

them to reset it and tell them the baffles are outa your pipe so they can allow for this. They will get it sorted almost spot-on and then you can make the final little changes.

Crackles and pops outa the pipe are ok if you can put-up with them but 2 b honest it would better for the engine if the baffles were in there.

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Just had a thought you say the guy you bought it off put on a different carb (new) Im not up on these bikes but is there not some kind of restrictor is it in the carb ????

if so you might have a restricted carb ??? that why its is not pulling properly , think it definatley carb now after you have given us more info

tell me to shut up if i am wrong , but here is another carb on evil bay if you fancy it

My link

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Just had a thought you say the guy you bought it off put on a different carb (new) Im not up on these bikes but is there not some kind of restrictor is it in the carb ????

if so you might have a restricted carb ??? that why its is not pulling properly , think it definatley carb now after you have given us more info

tell me to shut up if i am wrong , but here is another carb on evil bay if you fancy it

My link

i dont know if the carb was new or not but the previous owner has even goneto the stage of fitting a sucide shifter it wouldnt suprise me if he fitted a non standard carb

the carb on the bike is mikuni it loks the same as e bay one

were do i look on the carb to find the restricter

when i got it the gear nob of the sucide shifter was missing the guy said it vibrated off so guess he was riding it

he also said that having no baffles reduced back pressure a little so i guess it was working

could it be something simple like the clutch plates sticking remember its been stood for a while

when we put the carb back on after cleaning it it seemed ok for about 30 seconds but then started doing it again thats what my mate told today anyway

how much would it cost roughly to take it somewere an get them to rejet the carb i guess it needs to be done on rolling road same as cars?

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If the clutch plates are stuck the bike will lurch and stall...not 'Bog Down' as you described.It could be water in the fuel though!

water is heavier than petrol so sinks to the bottom of the tank and into the carb, it sits in the bottom of the carb and blocks the main jet but leaves the pilot jet clear, thus idle is ok but the bike wont rev

Remove the fuel pipe from carb and run some off using the 'Prime' position, then drain the float bowl and try again

...Paul

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"Failte" dan28, to the YOC club. rolleyes.gif

Im not really familar with your Drag but !

It could be many small things !

It probably is runing a bit ritch but it should at least take off spluttering down the street.

Then I would start at the tank and work my way to the carb again. If all was ok and the carb was working properly

Good luck mate !

New petrol

Check all pipes

Get fuel running to carb

Empty float bowl

Make sure choke is not sticking

Try again

But I think you might need carb re-jetted, the other guy (god knows what he did before he gave it to you--- he might of swapped carbs again) Sorry dont know how much it costs to get re-jetted, shouldnt b that deer!

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New petrol

Check all pipes

Get fuel running to carb

Empty float bowl

Make sure choke is not sticking

Try again

But I think you might need carb re-jetted, the other guy (god knows what he did before he gave it to you--- he might of swapped carbs again) Sorry dont know how much it costs to get re-jetted, shouldnt b that deer!

thanks for all the replys will have a go this weekend an let you know how it goes

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