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Discussion Starter #1
I just got this bike po said he changed carb I'm wondering if this carb is ok to run it idles well and had good response with no load when crusing it cuts out if you open it up. My other question is do I need the tps if so what is it doing
IMG_20200629_223452024.jpg
IMG_20200629_223837702.jpg
 

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2001 Yamaha XVS650 Dragstar Classic and 1999 Honda NT650V Deauville
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Hard to tell from the pic, but it looks to me like someone found some scrap and managed to fit the stock TPS to some kind of carb not made for the bike. Apparently through some kind of 2-1 intakes. 2-1 will only run well if both runners have the exact same length, which few tend to have. Then there is the jetting issues.

The running sympthoms suggest a lean condition. Do you use an air filter normally? If not, you can have running issues from air rushing past at 90 degrees, upsetting jetting as speed goes up.

IMO, the easiest thing to do is to revert to the stock setup. If you are adament to make this single carb work, you are most likely in for a lot of experimentation. Without a dyno and CO2-sniffer, that can be especially frustrating. At any rate, I would suggest tidying the whole thing up and make sure everything works as they should, but this solution looks more like a hack than a pro job to me.

The TPS affects timing, BTW, where the throttle position and the rate of change (snap open or open calmly) will adjust ignition timing to match. It is impossible for me to tell from the pictures whether the TPS is operational now, or just stuck on there.
 

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Discussion Starter #3
Hard to tell from the pic, but it looks to me like someone found some scrap and managed to fit the stock TPS to some kind of carb not made for the bike. Apparently through some kind of 2-1 intakes. 2-1 will only run well if both runners have the exact same length, which few tend to have. Then there is the jetting issues.

The running sympthoms suggest a lean condition. Do you use an air filter normally? If not, you can have running issues from air rushing past at 90 degrees, upsetting jetting as speed goes up.

IMO, the easiest thing to do is to revert to the stock setup. If you are adament to make this single carb work, you are most likely in for a lot of experimentation. Without a dyno and CO2-sniffer, that can be especially frustrating. At any rate, I would suggest tidying the whole thing up and make sure everything works as they should, but this solution looks more like a hack than a pro job to me.

The TPS affects timing, BTW, where the throttle position and the rate of change (snap open or open calmly) will adjust ignition timing to match. It is impossible for me to tell from the pictures whether the TPS is operational now, or just stuck on there.
Just got this bike don't know much about it and my knowledge on bikes doesn't go very far it has a kjs intake both sides looks like the runners would be the same length it has a K&N air filter on it I checked for voltage on the tps the blue wire has 4.0 volts key on engine off. that's a good idea to get an a/f ratio gauge and check it my concern is it running to lean I haven't rode a bike much at all but seems like the motor is hot and that may be normal just have to find someone with more experience than me and ask
 

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Discussion Starter #4
Just got this bike don't know much about it and my knowledge on bikes doesn't go very far it has a kjs intake both sides looks like the runners would be the same length it has a K&N air filter on it I checked for voltage on the tps the blue wire has 4.0 volts key on engine off. that's a good idea to get an a/f ratio gauge and check it my concern is it running to lean I haven't rode a bike much at all but seems like the motor is hot and that may be normal just have to find someone with more experience than me and ask
Here is a pic of the intake
IMG_20200629_223930319.jpg
 

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Discussion Starter #7
Have you checked the plugs that can tell you if you are lean. So it has a single carb? Some guys have tried them without much success. With the twin carbs the jets are different from front to back
I did check the plugs they are
Have you checked the plugs that can tell you if you are lean. So it has a single carb? Some guys have tried them without much success. With the twin carbs the jets are different from front to back
I did check the plugs I will send a pic the plug on the left is the front jug I need to verify if them are the right plugs I read in kjs website if your running straight pipes the carb has to be jetted also does the pipes need to be the same length? These pipes are definitely different lengths
 

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They look a little lean to me. The right one has a little carbon build up. As for the pipes mine arn't the same length either. But my pipes do have baffles. I am not real sure about the single carb set ups. You might try to richen and see if it helps. But if the manufacturer recommends. It makes sense with different lenght of pipes with one carb. The previous owner of mine said the jets were changed for pipes.

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They look a little lean to me. The right one has a little carbon build up. As for the pipes mine arn't the same length either. But my pipes do have baffles. I am not real sure about the single carb set ups. You might try to richen and see if it helps. But if the manufacturer recommends. It makes sense with different lenght of pipes with one carb. The previous owner of mine said the jets were changed for pipes.

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Thats a nice clean ride man. This is where im at with it now i noticed the engine light is on when running po told me it would always be on because of something to do with the fuel heaters im not really buying that. I checked codes im getting a 12 not sure what that is could never find any info on it I did check the tps im not getting no ohms reading at all on it idle or full throttle I will locate a tps and try it and see what happens
 

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Thats a nice clean ride man. This is where im at with it now i noticed the engine light is on when running po told me it would always be on because of something to do with the fuel heaters im not really buying that. I checked codes im getting a 12 not sure what that is could never find any info on it I did check the tps im not getting no ohms reading at all on it idle or full throttle I will locate a tps and try it and see what happens
i wonder if the code is for the tps?
 
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